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Microbiota - Science topic

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Is it a positive way to adopt sustainable agricultural practices as a way of protecting microbiota or to follow intensive agriculture in order to meet impending food crisis?
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Yes it is. Keep plant cover on the soil, reduce tillage, and add carbon from crop residues or manure wherever possible. It sounds simple because the soil biodiversity takes care of the complexity. Most intensive practices simplify and rely on inputs that are ultimately not sustainable—but we cannot trash them because they feed the 4 billion+ urban dwellers.
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Hello,
Do you know if is that possible to identify bacterial enzymes (from microbiota) by analyzing transcriptomics data from a human tissue (i.e. TCGA samples)?
Thanks for you response!
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Oh, I see.
Thank you anyway!
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The research topic is for final year graduation from bachelor's degree. I had a topic in mind such as Leaky gut syndrome: The imbalance between microbiota and
harmful bacteria, but due to unavailable equipment in our labs, I need other topics. Your help is appreciated.
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What are the available resources and facilities in your lab?
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Dear researchers
In my subject, I work on the characterization of the Moroccan marine microbiota by metagenomics under the discipline of microbial ecology.
During the sampling, we could not have all the in situ measurements of the Physico-chemical parameters of the studied microbiome. That's why we had recourse to the extraction of spatial data from the NASA website to complete.
my question is: do we have the right to combine our own data with those of a database to analyze them? ethical and copyright aspects. since these data are submitted to the public with open access.
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If it is open access I see no reason not to use it. It is however essential that you should properly cite them.
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Dear researchers
In my subject, I work on the characterization of the Moroccan marine microbiota by metagenomics under the discipline of microbial ecology.
During the sampling, we could not have all the in situ measurements of the Physico-chemical parameters of the studied microbiome. That's why we had recourse to the extraction of spatial data from the NASA website to complete.
my question is: do we have the right to combine our own data with those of a database to analyze them? ethical and copyright aspects. since these data are submitted to the public with open access.
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Samir Ranjan Panda , Man Kit Cheung , Phil Geis thank you very muche for your answers :)
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The diet we take has a role in microbiota which further influences the metabolic as well as mental health. Any evidence related to that?
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Visit kindly the following useful RG link:
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I am writing an essay on probiotics and faecal microbiota transplants etc. I am proposing a new treatment for generalised anxiety disorder exploiting the gut microbiome. I have to answer a question saying what is the biggest challenge for this.
I believe the answer is something like that all species are not currently culturable and that we don't even know all the species in the gut microbiome. Any further ideas?
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The current treatments that we have are mainly focusing on altering/causing a shift in the microbiome by the supplementation of probiotics, prebiotics, and postbiotics. Despite being popular, these treatments are not always useful and their beneficial effects are hard to detect.
Furthermore, we still don't understand fully the relationships between different bacteria and the way they interact in a complex matrix such as the gut.
Furthermore, pathogenic species of bacteria express their genes differently based on the environment they are found in. So understanding how they interact with other bacteria is key here to form a microbiome-based treatment.
Therefore, until we have a complete picture of the microbiome on a strain level and how these bacteria interact together or with their host, we won't be able to form novel microbiome-based treatments
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I found several databases but none of them matched the search I want to perform. I have a couple of metabolites which I would like to look up and see if they are associated with certain bacteria that may be part of the microbiota.
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Dr. David Wishart presented MiMeDB - Microbiome Metabolome Database (at November 2021 Nature Conference "Reshaping Microbiome through Nutrition). The release of the database was planned for January 2022: if you'll stay tuned with the Metabolomics Innovation Centre (LinkedIn), you'll know when it is launched. It is anticipated to have an integrated microbiome, metabolome and diet data.
In the meantime, HMDB database includes many subdatabases of metabolites (including microbial in origin). ECMDB, PAMDB, YMDB and FooDB may be helpful. Check https://www.metabolomicscentre.ca/software for all databases.
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We have done next generation sequencing for 16S rRNA for gut microbiota for cases (n=20) vs. controls (n=20). I would like to know how can we calculate relative abundance manually for cases vs. controls. I have read counts and OTUs for both the groups. Kindly suggest me.
Thank you.
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After the construction of OTU, I believe the QIIME2 might help you. You can find out more information at https://www.nature.com/articles/s41587-019-0209-9
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What is the minimum number of replications needed to do an experiment on rumen microbiota in calves? Do we need to do a power test? If yes, please suggest me a method? How about for in-vitro experiment? Thanks!
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at least six samples
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Hi all,
My experiment is to find the differences of micro bacteria in gut of marron Cherax caini. there were 2 groups of marron , one fed every day, and one fasted for 4 weeks. At the end of trial, marron gut were applied RNA gene sequences.
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What do you want to ask?
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I am attempting a scoping review on the amount of horizontal gene transfer among bacteria under antibiotic pressure (details are still a work in progress). I actually want to find out if different doses of the same antibiotic would effect the genome differently, would a bigger dose increase the spread of resistant genes via HGT in the colon, or would is the dose itself not play any role? But I cannot seem to find literature on how different doses of the same antibiotic affect the spread of plasmids via horizontal gene transfer in vivo. Am I missing something or is this simply unexplored?
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I'm sure dosage will have some effect but probably over a narrow range. Length of time of exposure is likely to be equally important. Remember that the antibiotic is not itself affecting or causing the spread, but rather imposing a selection on the population and letting rare events get amplified (by rare event here I mean some sort of transfer event).
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Hello,
in the literature, the studies based on the next-generation sequencing analysis of microbes are called "microbiome studies". On Wikipedia, the microbiome is defined as: "the microorganisms found in a specific environment". Microbiota is instead: "ecological communities of commensal, symbiotic and pathogenic microorganisms found in and on all multicellular organisms".
If I study the species richness of microbes in the gut, for instance, what should be the correct title of the work? "Microbiome analysis of the gut" or "microbiota characterization of the gut"? Or are the two terms simply synonyms?
Since I am not studying the interactions between microbes but only their presence, I think "microbiome" is the correct term. Am I right?
Thank you
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Dear Luigi Marongiu Please, take a look at this paper:
Microbiome definition re-visited: old concepts and new challenges (Berg et al. 2020).
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Is using fluticasone spray for allergic rhinitis ( or sinusitis) in the fourth month of pregnancy can alter the nasal microbiota ? What alternative can be used?
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Thanks Sir Khaled Elsayed
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Hello
We performed a study on the intestinal microbiota of rats in six intervention groups (8 rats in each group).
It is suggested that since the rats in each group were the same in terms of type of intervention and storage conditions and had the same genetics, the fecal samples of the rats in each group be pool together (ie we have a total of 6 pooled samples for the 6 intervention groups) and Then perform microbiota tests. (Investigation of microbiota composition and diversity by 16s rRNA method).
I want to use STAMP software for statistical analysis
Given the above description, what is the best statistical method for statistical analysis?
should I use from Whithe's non-parametric t-test (two groups) or chi-square test (two samples) or Another method in STAMP?
What is your suggestions? Thank you in advance for your help
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McMaster technique
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Anyone who has a protocol to study microbiota? How to maintain the guts, etc?
I want to begin studying microbiota from aged rats and I really know nothing about how to do that.
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Maria Jose Bellini .-. To begin with find some of the great reviews (I will try to find some to post later), but you can even begin with the basic information at https://en.wikipedia.org/wiki/Gut_flora . If you intend on culture methods, you need to find a good microbiological laboratory in your institution or a university that can process the samples. From the way you wrote the question I am assuming you might be more interested in a genomics approach (or metabolomics). For this you will need to find a lab that can process your samples (this would be too hard to set up for your own lab), and there are even commercial companies which can process your samples. I have used https://www.mrdnalab.com/ and there website will give you insight into a variety of methods.
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Dear colleagues!
I am trying to figure out how to do an extraction for soil microorganisms for further metabolomic analyses. I am only interested in the microbiota part, so I would like to discard any organic matter present in the samples.
Do you know any useful method for that? Any suggestions that could help me?
Thanks for your help!
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Hello
We performed a study on the intestinal microbiota of rats in six intervention groups (8 rats in each group).
It is suggested that since the rats in each group were the same in terms of type of intervention and storage conditions and had the same genetics, the fecal samples of the rats in each group be pool together (ie we have a total of 6 pooled samples for the 6 intervention groups) and Then perform microbiota tests. (Investigation of microbiota composition and diversity by 16s rRNA method).
The question is whether the results obtained from the pooled samples are different from the results obtained from the individual samples in terms of scientific validity?
What is your suggestions?
Thank you in advance for your help
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Hello Mohsen,
In agreement with previous answer, analysis of pooled sample will provide you nice information on the response of faecal microflora to your treatment. You will only miss individual variability within a pen compared to a trial with individual faeces collection. If the microbiota determination is the main objective of your study I'll suggest individual sampling, if not, pool is clearly sufficient.
Kind regards,
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I have seen in papers that many papers remove singletons from their microbiota data. I am not sure what is actually singletons and why the authors remove the singletons sequences. I would be happy if you share your thoughts and experiences about this matter. Thank you in advance for helping me.
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following
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Animals were fed DSS via drinking water and fecal samples were collected and DNA was isoklated using Qiagen stool DNA isolation kit. The extracted DNA was sent to a sequencing lab to be analysed for microbiota using diversity profiling/sequencing. The DNA sample however failed the QC. Next, I realized that DSS is a PCR inhibitor and hence interferes with the process. Did anyone face similar issue and how did you resolve this. Any advise will be much appreciated.
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Problem solved on using Zymo Quick DNA fecal/ soil micro kit. DNA extracted using the Zymo kit from DSS treated samples resulted in good number of reads in 16S sequencing.
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FMT is showing promising results in terms of treatment of recurrent gut infections. Could be used this approach (microbiota transplantation) for the management of chronic respiratory diseases with microbiological component such as COPD or CF?
Is there any research group that has tried to perform this procedure on the respiratory tree?
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It might not be a good idea to introduce more microbiota into the lung, as they are one cause for inflammation. How about using the cellular homeostasis maintenance function of autophagy/xenophagy to control the microbiota population in lungs, repair the dysfunctional epithelial cells, and decrease the overall inflammation level in the lungs:
Autophagy can e triggered by nutritional deficient stress like starvation.
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I'm looking for publication about the Isoptera and blatodea microbiota, so if any one can help about that, is there any study presents the microbiota of blatodea , crockoqch, Termite, I ll be so grateful.
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Thank's a lot for sharing
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I'm looking for research done especially the microbiota of Termite and crokoache thank's ( cafard, termite)
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What role do the body microbiota play in augmenting/neutralizing infection intensity in patients suffering from COVID-19? Do SARS-CoV-2 negate the competition from other viral and bacterial strains already present in the patient's body and vice versa? Is there a link between mild to moderate versus severe symptom development among people who have contracted the virus and the presence of specific microbial load in them, apart from their own physiology and genetics? Has there been any research on the possible effect of other influenza virus sub types (mostly B) on SARS-CoV-2? How much does the presence of a diverse microflora influence the onset of cytokine storm in case of infection by a foreign pathogen?
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Hi Sandra! I'm studying microbiota and their applications to the field of landscape architecture and came across your research. This is such an exciting project and I'm glad to see it moving to the prototyping phase. I'm wondering about the status of your research and whether you see this product moving forward and how/if you see it being applied in urban design and landscape. Looking forward to hearing back from you! Thank you so much, Lydia.
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The landscape design incorporates four major elements: defining a continuous pedestrian connection the length of the corridor, developing clear and safe crossings of the roadway, creatively resolving the need for pedestrian connections in an environmentally sensitive area. In some cases, you can add your own touch in the design models that are above or based on the regular standard.
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I already tested three different sequences and had problems with dimers and melt curve (low specificity). Any reliable primers? I'm studying rat microbiota with qPCR.
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Marilia Cavalcanti Some short 16S-homologs sequences are present in bacterial genomes, and you can get non-target amplification for microbiota samples. Try to use several group-specific primers and analyse group-specific dynamics
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Since ancient times over thousands of years until modern technological era human diet and drinks were simple devoid of chemical food additives.. With the advent of Modern technological era human drinks and diet are supplemented with various substances. Over 3000 chemicals or others are added as food supplements to prevent decay and please the eye. Food preservatives and other substances have tremendous influence on the microbiome of human intestine. Endotoxins produced by the microbial flora may result in endotoximia. This may be responsible for many diseases and maladies in man.
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Please also go through the following RG link.
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In general, plants host endophytes (bacteria and fungi) depending on phenological conditions.
Stinging nettle (Urtica dioica) has been widely recognized to be associated with endophytes and especially fungal species.
I am wondering if there are nettle leaves without any endophytic colonization?
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we've alreday isolated endophytes from diverse spontaneaous plant species, we found very interesting bacterial endophytes from Urtica urens. See (Krimi et al., 2016). Good luck!
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Hi all, somebody has a good protocol on how to perform NMR from human feces to track microbiota metabolites? I have zero experience with this technique and I found different protocols online but I don't know what's the best choice. Thanks!
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The Gratton paper also has important information on relative stability and heterogeneity of fecal samples - which is very high indeed -and is highly relevant to understanding the micro-ecological structure of the fecal samples. It also casts doubt on the ecological understanding of many microbiome/metagenomic studies which have to use quite large homogenised samples that give an averaged ecology- At some level it is always necessary to compromise in this way to get any sort of answer but it is fairly meaningless to cross correlate, for instance, metabolic data with microbiome data when the sampling heterogeneity and sample volumes are very different. If you use a large volume for metabolites then micro ecological heterogeneity information is lost. To illustrate- If we refer to the standard method of terrestrial ecological sampling using say 1 meter Square quadrats to sample species abundance (or by analogy metabolites in small samples) and throwing a series of these quadrats to statistically analyse the species composition and distribution in a field say- but if we throw a 200 m Square quadrat we could cover a much wider set of ecologies which could include a bit of oak woodland, some grassy pasture a corn field and a house with a wishing well... the average of this would mean exactly nothing! But the 200 m Square analogy is closer to what is often done in metagenomics!! This might be sidestepping the question a bit, but as one of the main aims of fecal metabolic analysis these days is to shed light on functional metagenomics the problem is worth considering. There are other big problems of course like the fact that collected fecal samples contain microbes that were functionally interacting with the host hours before and meters away (in intestinal space) under different physiological conditions= so what does that actually mean? Arguably the best place to look for microbiome related metabolites and microbe-host co-metabolites is in the urine because most absorbed compounds are made polar by host phase1 and phase 2 conjugation in the liver and then excreted by the kidneys (presence in the urine also proves they have actually been inside the body which is not true of many fecal metabolites). Hope this is of interest.
Gratton J, Phetcharaburanin J, Mullish BH, Williams HR, Thursz M, Nicholson
JK, Holmes E, Marchesi JR, Li JV. Optimized Sample Handling Strategy for
Metabolic Profiling of Human Feces. Anal Chem. 2016 May 3;88(9):4661-8. doi:
10.1021/acs.analchem.5b04159. Epub 2016 Apr 21. PubMed PMID: 27065191.
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Immune system and Inflammation impact on the Gut-Brain axis !
The Gut/Immune/Nervous (GIN) communication
New insights into how immune system and inflammation play a role in Parkinson's Disease
Nov. 2019
New research indicates that the earliest stages of Parkinson's disease (PD) may occur in the gut with a likely relation to inflammatory bowel disease (IBD).
Parkinsonism is not just a brain disorder, but a group of diseases that may have their onset in the GIT. It is strongly suggested that individuals with an increased tendency for peripheral inflammation have a higher risk to acquire PD. Given the potentially critical role of gut pathology in the pathogenesis of PD, IBD may impact PD risk.
Peripheral immune system alterations may play a role in PD, which has the potential for new therapeutic strategies. Understanding and appreciating the importance of the so-called gut-brain axis, the connection between gut and the brain in PD, has grown rapidly in recent years.
The inflammatory processes have naturally led to discussion of an association between IBD and PD since the two share some basic characteristics. IBD is currently considered an inappropriate immune response to the microbiota in the intestines, characterized by chronic pro-inflammatory immune activity, a trait now also suggested to be a fundamental element of neurodegenerative disorders.
Highlighting the relevance of the immune system, large genome-wide association studies (GWAS) and pathway analyses identified 17 shared loci between PD and seven autoimmune diseases including celiac disease, rheumatoid arthritis (RA), type 1 diabetes, multiple sclerosis, psoriasis, ulcerative colitis and Crohn's disease.
Many epidemiological and genetic studies have found that there seems to be an increased risk of developing PD among people with IBD. The association between IBD and PD may simply be that IBD is just one type of intestinal inflammation, so it is not IBD specifically that increases the PD risk but perhaps intestinal or peripheral inflammation in a broader sense.
Inflammation of the gut is only one of many symptoms on the list of changes in the gut and is associated with neural structures in PD patients. Thus, IBD might be just one of many sources of intestinal inflammation.
While IBD patients are more likely to get PD, the risk is still very small. Yet, for a given IBD patient, the probability of not getting the diagnosis is 95%-97%.
Future pharmacological therapies aiming at slowing or stopping PD progression should not only target patients well into the course of the disease, but also be administered to patients in the very early phases of the disease or at risk for developing PD.
Clinicians should be aware of early Parkinsonian symptoms in IBD patients but also in patients with chronic inflammatory disorders.
A focus on the potential role of the immune system and of systemic inflammation these neurological diseases is encouraged.
A clear knowledge of the mechanisms implicated in Gut/Immune/Nervous communication could help improve the prognostic and therapeutic tools leading to better quality of life for patients, reducing the exacerbation of PD symptoms, and delaying the progression of the disease.
Parkinson's disease is a slowly progressive disorder that affects movement, muscle control and balance. It is the second most common age-related neurodegenerative disorder affecting about 3% of the population by the age of 65 and up to 5% of individuals over 85 years of age. During the 20th century, PD was thought to be primarily a brain disorder, however, research has shown that it may actually begin in the enteric nervous system, the part of the autonomic nervous system that controls the gastrointestinal organs.
Source: Brudek, T. et al. (2019) Inflammatory Bowel Diseases and Parkinson’s Disease. Journal of Parkinson's Disease. doi.org/10.3233/JPD-191729
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.
I suggest reading this article-
Dinan TG, Cryan JF.The Microbiome-Gut-Brain Axis in Health and Disease. Gastroenterol Clin North Am. 2017 Mar;46(1):77-89. doi: 10.1016/j.gtc.2016.09.007. Epub 2017 Jan 4
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If suppose the soil shows magnificent suppressiveness against Phytonematodes, what would be the possible and radical microbiological techniques (For biotic and abiotic) to use to ascertain the latent of the suppressive world? Soil microbial community plays a crucial role in soil and plant health is Axiomatic factor, but the mystery is How to determine the significant differences between total and active microbes dwell over there. Let me explain here. DNA as sole evidence for the existence of a microbiota and you identify all the OTUs in that particular soil sample but the identification and existence of these OTUs doesn’t mean that all these microbes are active metabolically and additionally you can also find DNA from dying cells or spores or cell-free DNA but it does not necessarily indicate microbial life and an active microbiota in the sample. Transcriptomics could potentially address this issue but there are also some redundant and some not all of them criticize the mRNA based identification technique for the activeness of microbial community.
Let’s agree for a while with Chu et al. (2017) who used Propidium monoazide (PMA) a dye which intercalates only into double-stranded DNA, preventing it from being amplified by PCR
to remove free DNA from dead microbes prior to 16S rRNA gene amplicon sequencing, but Papp K, et al 2018 suggest that that RNA-based method to measure metabolic activity does not work equally well for all microbiome types.
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Dear Abhijeet Singh ,
Bunch of thanks for your answer. I hope it would be helpful Abhijeet Singh
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Hello,
I have two populations of Spearman's rho (correlation coefficients) for the influence of multiple microbial taxa on 4 host's phenotypes on different diets.
Is there a way for me to compare them?
As far as I know I can not use ttest (or can I if they are normally distributed)
Can I use PCA to group them?
My goal is to see if two communities of microbes (as a whole) provide different effect on the host depending on the diet, therefore I cannot just calculate p values for each correlation
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Andrei Bombin I am afraid that for 2 population you get only simple similarity value for corresponding correlation coefficients.
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I am analyzing an intestinal microbiota of rats by qpcr. I had already done the efficiency of my primers and analyzed samples of DNA extracted from feces and everything went well. Good melt curve and efficiency between 95 and 110%. When using the DNA extracted from the tissue of the large intestine, I am having problems with the melt curve that are strange as in the image, having two peaks, the reaction is the same, the same primer. Do you know what may be happening? If the presence of the mouse's DNA in greater quantity for being tissue may be hindering the reaction? I've tried with 50, 75 and 100ng of final DNA and the same problem remains
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Hi,
for me it seems like you see primer dimers. Sometimes high amounts of input can affect the melting behavior and might lead to such a behavior. You could load your samples on a gel to check this. In addition you might check it this behavior remains with lowered primer amounts. Other option would be to check another mix which was developed/ tested in microbiome applications like UCP Sybr green.
Best Sven
P.S. if you like you can send me the runs by mail. Just send me your email address via message and I will reply
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Hello fellow researchers
I am doing the microbiota profiling of fish intestinal feces and mucus. The samples I have used for DNA/RNA extraction were stored in RNAlater for about a year. I found salt crystals in the samples, which I suspect is due to a longer storage time. I removed the crystals before the extraction, however, I believe they affected the concentration of the eluted nucleic acid.
The concentration of the extracted DNA was just fine, however, for RNA it was very low. Therefore, now, I can only use the DNA for 16SrRNA sequencing, and can't perform metatranscriptomics as planned.
My question is, would you prefer storing samples in DNA/RNA shield for microbiota studies instead of RNAlater?? I understand that DNA/RNA shield can lyse the samples. I would really like to know what you would prefer the most and why?
Any help will be greatly appreciated!
Thanks!
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Hello Shruti,
I do not have a direct answer to your question because I have never used DNA/RNA shield. But I faced a similar problem of having very low RNA yield from samples stored in RNAlater. My experience is that RNA later interferes with the extraction of RNA. However, I avoided this issue after I learned that the RNAlater needs to "pressed" out of the sample using Kimwipes. I am not sure whether you could try the same with fecal and mucus samples. But you could try to blot your samples and remove the RNAlater by putting them on kimwipes without pressing.
This should definitely improve RNA quality.
Best.
Adnan
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I am working with DNA extracted from feces. I made a qPCR using concentrations of 100, 75, 50 and 20ng final. The CT value was very similar between dilutions between 29 and 30. My positive control has a CT of 23. I've done the primer efficiency and it's fine. Any reason for this to occur? From 100ng to 20ng should have some change. Since these are stool samples they may have inhibitors, but I don't know if they would affect this way
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A gap of 1 CT between two samples represent a 2-fold difference in DNA concentration. Therefore, between 20ng and 100ng you shouldn't expect anything more than a difference of 2 CT. Have you made triplicates ? My guess is that such a "small" difference is often hidden within the standart deviation of qPCR replicates.
Also, did you get a CT value for your negative control(s) ?
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Studies which used 16SrRNA analyse for fecal samples often write about the representation of the gut microbiota, but is this not to general? I am aware that some bacteria are attached to the mucus and might be less likely to end up in the feces. But what about the bacteria from the small intestine? Is it plausible that fecal microbiota represents mainly the large bowel microbiome?
Thank you in advance!
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The microbiota in different regions of the large intestine will vary for manly reasons, including the quality of food resources left along pathway, structure of the LI, differences in crypts/microstructures, food source for the region being sampled..... One paper related to this and cancer is https://cancerpreventionresearch.aacrjournals.org/content/canprevres/11/7/393.full.pdf
Do a full pubmed or scholar.google search for variations in microbiota in the LI.
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With the advent of modern technology man is using tooth paste containing antimicrobials commonly phenol derivatives which are poisonous to man. Can these antimicrobials affect the microbiome of human intestines leading to manifestation of many unexplained maladies of man.
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The following study reveals that fluoride also does not affect the gut microbiome.
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Skin, gut and vaginal microbiota normally maintains a symbiotic relations with the relevant organs. In some situations this symbiotic relationship is disrupted and dysbiosis occurs. Is there any genetic factor that influence the transformations of symbiotic status to dysbiosis?
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Hello,
you can find the answer to your question in the next publication:
Emiley A. Eloe-Fadrosh1 and David A. Rasko1,2
The Human Microbiome: From Symbiosis to Pathogenesis Annu Rev Med. 2013; 64: 145–163.
doi: 10.1146/annurev-med-010312-133513. It is free
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Dear all,
I am a beginner of R Studio and Tax4Fun.
When I try to input file of Tax4Fun, it always shows:
> importSilvaNgsData(inputFiles="yanglyu---ssu---fingerprint----Total---sim_93---tax_silva---td_20.csv")
Error in data[[rlabp]] : subscript out of bounds
I was wondering what is the correct format of this, could anyone please show me an example (best in picture) or give me some advice?
Thank you in advance
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Dear Yang,
I agree with Dr. Gautier Richard answer for this question.
You can also see this manual specific for Tax4Fun: predicting functional profiles from metagenomic 16S rRNA data analysis.
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I am trying to extract bacterial DNA from feces and cecum from mice, to then do PCR. I initially tried with phenol-chloroform and did not succeed. I had better results with CTAB, but the DNA band on the agarose gel is still weak. Would anyone have some protocol with CTAB so I can see what adaptation I could make?
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you can try potassium acetate method of DNA extraction.
some Extraction kits are also online available eg. himedia DNA extraction kit.
best wishes.
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Which model is most suitable for working with antibiotics-induced microbiota depleted in rats wistar?
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Thank you Sriram Seshadri!
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Does all disease begin in the gut (intestines?)? The statement by Hippocrates seems to be gaining more traction as we learn more about the intestinal microbiome, but is it true? Is it mostly true? What might be the exceptions, or where is the cause from different sources but the intestinal microbiome makes it worse. What about the inflammatory effects from the microbiota or their metabolites?
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Not all diseases start in the intestines.
I heard about wisdom say "Stomach is a house of sickness and fasting is a medicine"
The makeup of bacteria within our gut determines whether we are likely to have GI conditions like colitis or irritable bowel; psychological states like depression or anxiety, skin disorders like eczema or psoriasis, neurological disorders like multiple sclerosis, Parkinson’s or Alzheimer’s Disease; inflammatory conditions like rheumatoid arthritis, systemic sclerosis and ankylosing spondylitis; even susceptibility to being overweight can be mediated by the microbiome’s impact on thyroid autoimmunity and insulin resistance.
Reference ->
Dr. Ronald Hoffman
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I have three (or possibly four) time points.  How many replicates from each time point is sufficient and how many reads should I aim for per sample?  
I am looking at sequencing the V4 region of 16S and some centers offer a reasonably priced service (around $50/sample) but only guarantee ~10,000 reads/sample.  My pilot project was sequenced on a miseq 2x150 and cost well over $1500 for 6 samples with between 0.5 - 1M reads per sample.  Can I get away with fewer reads if I can then afford more replicates?
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Hi Anna,
thank you very much for your detailed information!!!
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Hi all,
I will be trying to demonstrate enteric neuron and glia cell structural changes in cell culture and ileum/colon tissue samples for the first time but couldn't decide my antibodies yet. Anyone who has an experience on HuC/HuD, PGP 9.5 or any other possible antibodies you may have tried, please let me know.
I am planning to use s100B, GFAP, sox10 antibodies for glia cells for whom could be interested. I would be glad to hear any kind of advice.
Thanks in advance
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It also really depends on what you want to see. If you are more interested in nerve fibers and neuron processes you might want to try PGP9.5 or have a look at beta III tubulin, which is neuron specific as well. This antibody is mainly used in enteric neuroscience, as well as HuC/D. HuC/D is very useful if you want to image neuronal cell bodies. ChAT and nNOS antibodies can be used if you want to show that different neuronal subtypes are present in the ENS. Then you could also stain for calbindin, VIP, calretinin, etc. But for a general overview of neurons and glial cells I would use HuC/D or tub bIII, and S100b or GFAP (try different combinations to see what works best for you). Sox10 will show you both neuronal precursors as well as (mature) enteric glial cells. Hope this helps!
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I'm interested in do a comparative study, between the normal microbiota and the microbiota present in captive spider monkeys.
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I intend to work on the microbiota of human breastmilk comparing two different collection methods. How do i calculate the sample size?
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I agree with Dr. Busi
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I am trying to find which are the best events/meetings in Microbiota during 2017 and 2018, because of a new translational research project related to human intestinal and vaginal microbiota, and it's influence on fertility.
The events I am looking for can be world-wide.
Thanks in advance.
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Keep an eye to the International Human Microbiome Consortium.
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We are looking for person/team able to run and further analyse microbiota of few artificially selected Drosophila strains. A selection was made on high protein diet or late reproduction. Now these flies show interesting phenotypes and we analyse them as much as we can or looking for possible collaborators to extend this project. Please contact me here or by mail olushchak@yahoo.com
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You must better investigate the microbiota from the human umbilicus dermal plica, which encounters 5000 species and may be different in known 5 races or may be by every individual.
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Dear all,
We are currently working on the methodology of randomized control trials (RCTs) for fecal microbiota transplantation (FMT) treatment.
The objective of this study is to identify most relevant designs of RCTs in FMT treatment.
In order to do this, we created short-vignettes comparing different designs of trials.
If you are a specialist of FMT treatment, we would like to collect your opinion on this subject.
Please click on the following link to begin the survey: http://clinicalepidemio.fr/FMT-design/
Your participation in the survey is voluntary, anonymous and should take you about 10 minutes to complete .
Thank you for your time and cooperation.
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Fecal microbiota transplantation (FMT) has gained mainstream attention with its remarkable efficacy in treating recurrent Clostridium difficile infection (RCDI) when there are no other effective therapies. Methods of selecting donors and routes of administration vary among studies.
I agree with yours four points, Aida.
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The human microbiota/ normal flora comprises the populations of microbial species that live on or in the human body. The biggest populations of microbe reside in the gastrointestinal tract. Evidences showed that the gut is the epicentre of antibiotic resistance. How these microbial population (that are estimated to be over 1,000 different species) contribute for antimicrobial resistance?
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Antimicrobial resistance is multi-factorial. Sub-optimal exposure to antimicrobial, gene transfer (both horizontal and vertical), spontaneous mutation are among the many. When there is frequent infection, there will be exposure to broad spectrum antimicrobials which will result in selection pressure in which resistant strains are selected. These strains will constantly evolve and result in gene transfer, both horizontal and vertical. The spontaneous mutation also contribute to the emergence of resistance.
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The gut-brain axis (GBA) connects this organs by means of neural, endocrine, immune, and humoral links. Where should we look for anatomical connection in thia axis (are there any?).
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Thank you very much for your answer. I am still looking for the connections through the connective tissue, maybe with the use of fat tissue? (the remnants of the dorsal and ventral fetal mesentery?) regards SW
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Carbohydrates, proteins or fats.
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Our microbiome's health is a function of a balanced mixture of carbohydrates, protein, inorganic nutrients, and cellulose. Optimal balance would be a function of the needs of an individual.
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We need to preserve the total DNA and RNA from host fishes and their microbiota on the field. The samples collected will be used for metagenomic and metatranscriptomic analyses. On the field, the samples can't be kept frozen (very remote location), but at best, they can be kept at 4 degrees Celsius for a few weeks before DNA and RNA extraction.
What is the best method to preserve and optimize the yield of host and microbiota DNA and RNA collected from our samples?
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Dear microbiota specialists,
I have to analyse variations of gut microbiota phyla and genus in a clinical study. I have 3 groups of treatment, a first stool sample collected at the beginning and another at the end of the protocol for each individual.
I would like to express differential values for Lactobacillus group for example, from data in log10 (ex : t1=8,3 and t2=8,6, but differences could also be negative), I traduced all my data in "real number" (10^8,6) and calculated the differences, but on graphes I have almost half of my values with hight positive scientific number and also negative => big error bars, even if I convert the differential value in log10.
And I know that it is not correct to simply do 8,6-8,3=0,3 because it does not reflect the reality...
So is it better to come back to OTU values ? Is there another way to correctly express differential values and to do multivariate statistical analysis at the end ?
In addition, do you normalize your data on total extracted 16S RNA ? per g of faeces ? or on total bacteria ?
Thank you for your help !
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Thank you all for your great answers !
I will take into account all of your comments, certainly for the next study, because for this one, a misunderstanding caused me to misinterpret the delta variations I had in my hands, but going back to the source, I realized that it was qPCR data. We went back in numbers and we made fold changes to respect the established statistical plan. I hope that it's correct !
However, I have other projects with sequencing data and your comments will help me to interpret the results.
Thank you!
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  • My study will require microbiota profile. Unfortunately, we dont have facilities and skills to do that or collaborators. So im thinking of sending the samples for analysis.
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Hi Dianne,
You can send it to Macrogen co. located in South Korea. They will receive genomic DNA of your samples or just a few amount of your samples and will go ahead will Microbial profiling according to your request.
good luck
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Elaborating, can we use these indices to determine diversity/abundance of 2 microorganisms at different skin sites (e.g. stomach, neck and hand) rather than determining the complete microbial composition at the 3 skin sites and then determining the Shannon and Simpson indices for 2 selected micro organisms?
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I suggest, you observe and calculate species abundance for ith species from your data set separately. Shannon and Simpson indices represent the diversity of a community as whole.
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Is there any study out there where the genetic risk for IBD has been addressed in the context of a certain microbiota composition, say enterotype, or according to presence/absence of indicator species or metabolic pathways?
We have recently published that for colitis induced by T cells transferred into Rag-deficient recipients, the expression of T-bet by the T cells matters only in the context of a certain microbiota. In one type of recipients, T-bet was critical for disease and T-bet-deficient T cells were unable to induce inflammation whereas in another set of recipients T-bet-deficient T cells induced inflammation just as potently as WT T cells did.
Has anything comparable been shown for humans, e.g. that gene XYZ confers an increased risk for IBD only in the context of a Genus abc-dominated microbiota. Or the other way around, say some kind of dysbiosis predisposes an individual for IBD only in combination with a certain genetic risk factor?
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genetic risk for IBD and microbiota or entero*
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I'm working on a sampling protocol in order to study the total microbiota of the mammary gland tissue in other species than humans (notably in food animals). I'm interested about current methods in humans (specially sample treatment after collection) that could be applyed in other species.
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I would recommend the methodology suggested in the following article although other researchers don't use iodine but use other antiseptic washes to remove contamination from the skin which may also be very good.
The human milk microbiome changes over lactation and is shaped by maternal weight and mode of delivery1,2,3,4 Raul Cabrera-Rubio, M Carmen Collado, Kirsi Laitinen, Seppo Salminen, Erika Isolauri, and Alex MiraAm J Clin Nutr September 2012 vol. 96 no. 3 544-551
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Our research is focused on the impact of glyphosate on soil microbiota. Just now, we want to evaluate the biological inhibition of nitrification in the rhizosphere of Avena sativa (used as cover crop in Argentina) treated with glyphosate as dessicant . We would like to perform the colourimetric microplate assay developed by O' Sullivan et al (2017).
We need to test BNI against a control of Nitrosomonas europea and/or Nitrosospira multiformis, which are sold by ATCC but are quite expensive in terms of our funding resources.
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Hi Maria,
I have upload the Poster of the EGU Conference from 2015 to my profile.
Cheers,
Tina
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Fecal microbiota transplantation in as alcoholic hepatitis and non alcoholic steatohepatitis is emerging
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Affirmative.  The gut microbome - liver axis is now well accepted(Compare et al. 2012) and there is significant body of evidence supporting gut microbiota plays role in nonalcoholic fatty liver disease (NAFLD) and exacerbate this to more dangerous nonalcoholic steatohepatitis (NASH) (Abu-Shanab and Quigley 2010). The overall school of thought is that the altered flora lead to dysregulation of the liver innate immunity and excessivle TLR stimulation (Miura and Ohnishi 2014). In fact E. coli mediated Small intestinal bacterial overgrowth (SIBO) is significantly increased in pediatric nonalcoholic steatohepatitis (NASH). Very interestingly Janssen et al recently reported the link between gut microbiota and bile acids(Janssen et al. 2017). In the Asian context we have observed SIBO, specially mediated by of Gram-negative pathogens result innate immune dysregulation (Ghosh 2011), insulin resistance, choline deficiency which are all signs of NAFLD, but this has not been published yet. Together, application of strategic probiotics in mitigating liver disease in high risk cohorts is increasingly suggested (Xue et al. 2017).
Suggested References
Abu-Shanab, A. and E. M. Quigley (2010). "The role of the gut microbiota in nonalcoholic fatty liver disease." Nat Rev Gastroenterol Hepatol 7(12): 691-701.
Compare, D., et al. (2012). "Gut–liver axis: the impact of gut microbiota on non alcoholic fatty liver disease." Nutrition, Metabolism and Cardiovascular Diseases 22(6): 471-476.
Ghosh, D. (2011). "Probiotics and intestinal defensins: augmenting the first line of defense in gastrointestinal immunity." probiotic foods in health and disease. Oxford& IBH Publishing Co, Delhi: 61-74.
Janssen, A. W. F., et al. (2017). "Modulation of the gut microbiota impacts nonalcoholic fatty liver disease: a potential role for bile acids." J Lipid Res 58(7): 1399-1416.
Miura, K. and H. Ohnishi (2014). "Role of gut microbiota and Toll-like receptors in nonalcoholic fatty liver disease." World J Gastroenterol 20(23): 7381-7391.
Xue, L., et al. (2017). "Probiotics may delay the progression of nonalcoholic fatty liver disease by restoring the gut microbiota structure and improving intestinal endotoxemia." Sci Rep 7: 45176.
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Im trying Candida selection in Sabouraud %2 Dextrose Broth. I need inhibit oral bacteria. What antibiotic concentrations should be used ?
Possibly, Vancomycin 7.5 mg/L for Gram positives , what about Gram negatives? and in which concentration is advised?
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You can use chloramphenicol to inhibit the growing of gram positive and gram negative bacteria. The usual chloramphenicol concentration is 0.05 g/L.
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How can I best collect samples from the small intestinal (ileal) microbiota of neonatal mice (e.g. postnatal day 3 or 7) for 16S amplicon sequencing? The neonatal intestine is very thin and ruptures easily, so it is almost impossible to squeeze out its contents as done for adult mice. People have published to just snap freeze the whole intestine including the host tissue and extract DNA from there but I am worried that the 16S amplicon PCR will be inhibited by the huge excess of eukaryotic DNA. Other people have published to scrape out the contents of the opened intestine but again I am a bit worried about the fragile tissue. In a third paper, the authors had to pool 6-8 mice per time point because there wasn't enough material to sequence individual contents. So, could anybody recommend a protocol for the isolation of ileal contents of neonatal mice? Thanks!
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Thank you both for your helpful answers.
I indeed separated the contents as much from the host tissue as possible and the PCR worked just fine even for day 3 using individual mice (no pooling required). I used a forceps to carefully squeeze out the colon in one piece and the ileum in 3-4 pieces of 1 cm length each. 
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I want to check microbiota in human stool. When I run PCR with DNA isolation from human stool, I compared the bands from reaction system of Phusion Master Mix with HF Buffer and DreamTaq PCR Master Mix. Each sample got a single band. But except positive control, band of the same sample from the two different reaction system didn't share the same bp. Who could tell me what is the reason? Which Master Mix should be trustworthy?
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 It would be helpful to know what your primers are, what your expected PCR product size should be, and what you are getting on the bench for your PCR product size. Knowing this may help to narrow down your possibilities; however, I think that there are a couple possibilities (besides the issues brought up by Sonam Mehrotra) with the most likely being that not all polymerases are created equal.  
Phusion Polymerase has high GC-Rich PCR Performance while DreamTaq is low. Depending on the consortia in the stool sample and what primers you are using you will have different GC content. This variation could affect the specificity of your primers and lead to the PCR bias giving you two different size products.
What are your primers?
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Does anybody know a protocol to deplete lung microbiota? If so, do you know if the protocol modifies intestinal microbiota?
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I don't have an answer, but I have the same question. Do you have any clue by now?
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Dear collegues
I am sure that the metabolites of microbiome make a special microenvironment for the division, diffenrentiation and function as well as the death of the gut endotelial cells . The machinery of the pathogene-induced inflammation and immune protection against the pathogens is rather well investigated. What can you say about the action of the "good" mictobiome and its translocation through  the healthy gut burrier for the processes mentioned above? If you have the articles aboiut it I'll be happy to get them.
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Hi
Healthy microbes can easily turn rogue. Those in our guts are undoubtedly helpful, but if they cross the lining of the intestine and enter our bloodstream, they can trigger a debilitating immune response. The same microbes can be beneficial allies or dangerous threats, all for the difference of a few millimeters.
Conversely, “unhealthy” configurations of microbes can be normal, even necessary. Ruth E. Ley at Cornell University and colleagues demonstrated this in dramatic fashion when they found that microbiomes go through a huge upheaval by the third trimester of pregnancy. They end up looking like the microbiomes of people with metabolic syndrome — a disorder that involves obesity, high blood sugar and a higher risk of diabetes and heart disease. These communities might indicate someone on the verge of chronic disease — or merely motherhood. Packing fat and building up blood sugar makes sense when you are nourishing a growing fetus.
 another example. Common medical wisdom says that healthy vaginal microbiomes are dominated by the acid-making Lactobacillus group that creates an inhospitable environment for disease-causing microbes. But Larry J. Forney at the University of Idaho and colleagues found that a quarter of women didn’t fit this pattern, despite being perfectly healthy. They also showed that their vaginal communities can change dramatically and rapidly, even over a single day, flitting in and out of states that are supposedly conducive to disease, but with neither clear causes nor ill effects.
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are there any ongoing clinical trials using fecal transplantation for children with autism?
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Please, evaluate one paper about children, and another total clinical trials.
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Things seem to be fine until line 28, when I attempt to actually call the randomForest method. I'm new to R and am still getting used to the language.
The code is listed below:
{
install.packages("randomForest")
install.packages("biom")
install.packages("rjson")
library(randomForest)
library(MASS)
library(biom)
library(rjson)
getwd()
file.exists("Subramanian_et_al_otu_table.biom")
Subramanian_et_al_otu_table <- system.file("extdata", "Subramanian_et_al_otu_table.biom", package = "biom")
Subramanian_et_al_otu_table
x=read_biom(Subramanian_et_al_otu_table)
biom_data(x)
as(biom_data(x), "matrix")
p <- as(biom_data(x), "matrix")
set.seed(131)
example.rf <- randomForest(rand ~ ., data=p, mtry=2, importance=TRUE, do.trace=10)
}
The seed value (131) here is trivial. When attempting to execute that last line of code, I get the following error:
  • Error in eval(expr, envir, enclos) : object 'rand' not found
Any help would be much appreciated. Thank you!
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Dear Joseph and Amir,
Sorry for the terribly late response.
Thank you Amir, for pointing out that rand was not defined.
I read Joseph's response and didn't understand what it meant at first because I didn't have enough experience using R and didn't have a clue on how to use the RandomForest package. This was my first project using R and furthermore, my first project using machine learning.
Our team eventually found out how to make it work and completed our project after much googling and a skype session with one of the authors of the paper.
After having solved the problem, I admit that replying to this post took a backseat on the list of priorities. It was quite rude of me to leave you hanging as I did. Although it's very late, I've come back to thank both of you for your help and apologize in hopes of setting things right. Again, many apologies.
We managed to replicate the microbiota-to-age model found in the Subramanian et al. paper to a satisfactory degree (although it wasn't precisely identical) and have moved on to work on other metagenomics projects. We did run into other problems after this one, (having to do with rarefaction and another part of modeling) but that is a story for a different time.
Thank you both for your time and your contribution.
Sincerely,
Isaac
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Microbiota, infant
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By searching NIH REPORTER (with key words: microbiota, infant, multi-center), there are three projects currently active/ongoing. You might also want to loosen/modify the keyword terms to get more exhaustive search results. 
1.  5R01DK095869-03: " THE RELATIONSHIP OF FECAL MICROBIOMES AND NUTRITIONAL STATUS IN CF", Contact PI / Project Leader: HOFFMAN, LUCAS R., Awardee Organization: UNIVERSITY OF WASHINGTON
2.  1R01DK109692-01A1: " EARLY CHILDHOOD DIET, GROWTH, GUT MICROBIOME AND LUNG HEALTH IN CYSTIC FIBROSIS",  Contact PI / Project Leader: LAI, HUICHUAN J, Awardee Organization: UNIVERSITY OF WISCONSIN-MADISON
3. 1R21HD088005-01A1: "ANTIBIOTIC EFFECTS ON THE DEVELOPING MICROBIOME METABOLOME AND MORBIDITES IN PRETERM NEONATES.", Contact PI / Project Leader: NEU, JOSEF, Awardee Organization: UNIVERSITY OF FLORIDA
Hope the information would be somewhat helpful. 
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Hello,
I'm interested in quantifying the number of bacterias in various samples (from fly microbiota), in order to compare the effects of 2 treatments. One treatment may diminish the abundance of bacterias compared to the other.
I generated OTU tables from the results of a MiSeq analysis, and I was wondering if I can use the number of reads as a way to compare the abundance of the OTU between my treatments.
I know that I can easily perform relative abundance of the OTU intra-sample, but I would like to do it inter-sample (and never saw this in the litterature).
Since I extract total DNA (fly dna + bacterial dna) should I normalize the quantity of DNA before my pcr ? Any ideas ?
Thanks
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Bonjour!
Maybe you can do the relative abundance of the OTU or OTUs comparing with the fly number of DNA sequences (if you have any of them in the Miseq reads), You can't use only the number or reads because the numbers of reads per sample have differences due to the methodology, it is impossible to obtain the same number of reads per sample. I mean, with Miseq reads you have relative abundance, you can't talk about total abundance.
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I am looking for some easy methods to identify rumen micro-organism
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Hi , Please look in attach file
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I am trying to compare different population according to energetic income and food composition.
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16S rRNA sequencing (V3-V4) will be good for this type of studies. I did similar type of studies for probiotics supplemented groups versus normal food eating groups. We find the changes in the microbiome following probiotics supplementation. Now we want to find out the mechanism, for which we are going to do the metatranscriptomis and host transcriptomics.
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I have 26 individuals from whose we extracted the microbiota over 20 times or so per individual. So, after cleaning and filtering the data, we ended up with 50 different OUTs and we conducted a LSA (Local Similarity Analysis) to see the correlation between the OTUs in each individual separately. 
We saw that the correlation matrices were more or less equal between each other, and I conducted also a pairwise Mantel test to see if there were statistical differences between the subjects. The results shown that they were the same kind of correlation matrix. 
So, my question is this: we want to join all the information into one matrix to make easier the interpretation and visualization of the data. I did the mean of the values, but I think that with this method I'm loosing valuable information. Do you know how it can be done properly?  
Regards.
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maybe its better to freshly calculate correlation based on groups instead of calculating metrics of metrics. Maybe this gives inspiration: http://stats.stackexchange.com/questions/4040/r-compute-correlation-by-group
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Trying to separate microbiota from mice feces, but I'm unable to convince myself that 400 x g will pellet all the large debris after I homogenize the fecal sample. (got the speed from a paper that completed a similar procedure)
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Using 400g, your bacteria will stay in the supernatant. You have to take care to separate the bacteria from the debris by vortexing. And then, just check your supernatant by microscopy to evaluate your samples.
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Is it possible to use common biochemical methods (chromatography, etc.) to determine the existence of metabolites naturally produced by microbiota in stools (i.e. acetate, butyrate)? We have no MS or NMR so that we're looking for unexpensive (and accessible) methods for these purposes.
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Yes, it is possible. Perhaps the MALDI-TOF method is the best option, but  the challenge is how to built the matrix
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How to differentiate mosquitoes midgut microbiota using 16S ribosomal RNA gene analysis?
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I suggest you to contact Luca Mazzon from my Dept. (lmazzon@unipd.it)
best regards
Carlo Duso
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Hello everyone,
i am conducting microbiota sequecing using MiSeq.
 i wrongly set the PCR program one cycle more as follows:
95 for 3min
-95 for 30s  <----|
-55 for 30s      8cycles
-72 for 30s-------|
72 for 5min
Hold at 4
So i was wondering will this mis do a lot harm to the result?
or should i start all over the index pcr?
Could anyone kindly tell me.
Thanks!
best regards,
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Do you mean you carried out 9 cycles? If so I'm sure it will be fine and you should be checking the insert size and DNA quantity before taking the libraries any further anyway. 
You may have a higher library concentration than expected but could dilute to the correct concentration. 
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Microbiota differs between colonic segments? Colonic segments differs in microenvirioment?, ph? micronutrients? water content?
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Some authors mention the rectal sparing or patchy rectal involvement in UC. However biopsy and resection tissue results recommend that there is no "Absolute rectal Sparing in UC". CD has rectal sparing mostly and indeterminate colitis can have all types though. Some authors blame higher H2S concentration in rectum to explain more severe rectal involvement. However, nobody knows. Likely it can be explained by genomic variant and microbiata species in vulnerable people. Sometimes even a simple antibiotic treatment kills good bacteria and triggers sleeping IBD as it does for C diff. "Way to go!"  
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mcr1 in bacteria confers resistance to colistin 
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