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  • Fadaka Adewale, Oluwaseun added an answer in Acetylcholinesterase:
    Can anyone help with the sequence of acetylcholinesterase gene in mice, maize & cowpea and primers used in acetylcholinesterase gene expression study?

    Can anyone help with the sequence of acetylcholinesterase gene in mice, maize and cowpea and the possible primers to be used for acetylcholinesterase gene expression study?

    Fadaka Adewale, Oluwaseun · Afe Babalola University

    Get to know the gene that encodes for the protein or better still go to NCBI and search for cholinesterase in mice, cowpea and maize genomes and copy the sequence is fasta file format then primers can be designed from there. Or from NCBI go to IDT DNA.com, click on primer design tools....and so on. 

  • Michal J Radziwon added an answer in Operative Dentistry:
    Can anybody suggest a method to segment the pulp area from the tooth radiographs?

    I am a masters student, and in order to work on my project (coding in matlab)  i need to get segment the pulp area of tooth from the dental radio graphs.Would anybody suggest some apt methods to do the same! 


    Michal J Radziwon · PurpRavn

    MESR is nice, when you have several perspectives on the same scene. It's not optimal for single image segmentation.

    it may sound naive - but it works extremely well - have you tried a magic wand in photoshop?

    if you want more scientific approach and know exactly what you do try to search on image segmentation. Good start point here:


    My rough guess would be that edge detection/follow methods can give here good results. Here is a small review:

  • Robert Schnittker added an answer in Fluorescence In Situ Hybridization:
    How critical is aminoallyl-dUTP when performing DNA FISH?

    Hello, I'm currently working on DNA FISH (Fluorescence in situ hybridization).

    So, I've been doing nick translation following the invitrogen protocol (https://tools.thermofisher.com/content/sfs/manuals/mp32951.pdf).

    However, I've notice that this protocol doesn't use aminoallyl-dUTP while other protocols do.

    When I proceeded with this protocol, I didn't get the expected result.

    To my knowledge, aminoallyl-dUTP is a critical material when performing DNA FISH, but if I'm wrong, please correct me.

    Is there a mistake in this protocol, or am I doing something wrong?

    Thank you for your time and consideration.

    Best regards,


    Robert Schnittker · Stowers Institute for Medical Research

    I too am using this kit, have you had success with it?


  • Antoine Campagne added an answer in Adherent Cells:
    Does cell debris & remaining trypsin effect cell healthy in cell culture?

    Hello All,

    Is it true that floating cell debris & remaining trypsin in culture media can effect healthy of monolayer adherant cell in cell culture? If yes, how? releasing cytokine.

    I learned that someone always centrifuge & discard media after inactivating trypsin or change the media on next day after sub-culturing cells to remove trypsin and cell debris. Does this step really matter?

    I usually culture neuroblastoma which is tough, and never have any problem with with leaving trypsin or cell debris in media. If I remove trypsin and cell debris, Could it make cell become healthier?


    Antoine Campagne · Institut Curie

    Unless you cultivate your cells in serum-free media (which could be the case for neurons actually), I don't think that the remaining trypsin can affect the cells. It is not the media but the serum present in the media that inactivates the trypsin. Indeed, FBS contains protease inhibitors, such as α1-antitrypsin and α2-macroglobulin that stop the trypsinization process. That is actually the reason why you wash your cells with PBS before the trypsinization step.

  • Kenneth M Towe added an answer in Global Warming:
    [Global Warming] Mitigation and Adaptation: which is more important ?

    Most climate issues' stakeholders do not deny that, we need to develop a "integrated series" of mixed policy, both to reduce greenhouse gas emissions (mitigation strategy), but also to deal with the consequences of global warming (adaptation strategy). The biggest divide is over which strategy should be paid more attention to.

    My dear peers, what do you think about it ? Any contribution is greatly appreciated.

  • Marcoen J.T.F. Cabbolet added an answer in Research Ethics:
    Is this example of research considered misconduct according to US Government?

    You are doing an experiment sponsored by the National Institutes of Health, a U. S. federal agency. In your experiment, you are testing the impact of a new method of exposure to chlorofluorocarbons to lung tissue using low-dose spiral computerized tomography. The protocol you are using was already approved and requires you to screen 200 subjects. You have completed 190 subjects and need to do just ten more. However, it is time for spring break and you really want to go with your friends. You decide to use the date for the 195 subjects and extrapolate the results for the remaining 10.

    Look up what "research misconduct" is according to the US government. Is this research misconduct? Why or why not? Would it be misconduct if, because of sloppy records keeping, you actually thought you had completed 200 subjects only later realized your error of having completed just 190?

    Marcoen J.T.F. Cabbolet · Vrije Universiteit Brussel

    As said above: you have to be honest. But still your findings can be publishable as the preliminary results of an incomplete study, in particular if you have very interesting data (e.g. nearly all positive or nearly all negative). You will have to emphasize that the size of the test group doesn't satisfy the minimum requirements, but still the publication can be interesting if you have observed a significant effect or a null result. In the results section you simply give the results of the 190 tests and you explicitly state that this is not enough to meet formal requirements, but in the discussion section you could for example argue (using statistical analysis) that even if you would have done 10 additional tests with a negative result, then still the conclusion would have been that a significant effect has been observed (e.g. because you have already 180 positives out of 190 tests). Although minimum standards are not met, such a paper might yield a motivation to repeat the test at a larger scale.

  • Raid Amin added an answer in Basic Statistical Analysis:
    How do I confirm whether my data fit the quadratic model if my R2 is 0.84 but lack of fit is significant?

    Model is significant with p value of 0.001.

    Lack of fit is significant too.

    Raid Amin · University of West Florida

    A link on a pdf on Tukey's Ladder for Re-expression:


    A link on Box-Cox Transofrmations:


  • Pavel Trávník added an answer in Organic Dyes:
    Does anyone have information about organic dye?
    1. I have a project for staining rodent chromosomes and cytoplasm  of rodent  oocyte with organic or plant dyes I need procedure for this purpose and I need more information about these dyes 
    Pavel Trávník · Sanatorium REPROMEDA

    Dear Zainab,

    Prof. Slaninova from Masaryk University is an expert in this area. 

    Ask on the ipokorna@med.muni.cz.

    Best regards.

    Pavel Travnik

  • Yambem Tenjing asked a question in Species:
    Does anybody know this species?

    Please mention which species it will be.

  • Giovanni Giulio Valtolina added an answer in Cultural Research:
    How to use schwartz framework for study culture of a country which is not in his study?

    Hello everyone

    I am going to use Schwartz framework for a cross cultural research but one of the countries in my research (Iran) was not mentioned in his research. Do you think can I use his framework or not?

    Thank you for your time

    Giovanni Giulio Valtolina · Catholic University of the Sacred Heart

    I agree with colleagues. I also used a framework, applying it to other culture.

  • Serge V. Shil’ko added an answer in Polymer Composites:
    Which natural fiber behavior is well suitable for Polymer composite applications?

    Plant with its botanical name you can suggest and why this is well suitable NF?

    Serge V. Shil’ko · National Academy of Sciences of Belarus

    The review attached and concerning application of natural fibers in polymer composites may be helpful for you. For the elaboration your question and fruitful discussion comment, please, what do you mean when saying "fiber behavior'. Best regards  

  • Maryam Golshani added an answer in Recombinant Protein Expression:
    Why can't I express my recombinant protein?

    We are having trouble with several systems of recombinant proteins expression. Different plasmids (pET, pGEX, pRSET), in different cells (BL21 (DE3), HMS, bl21 STAR). All systems were functional before, but now none of them are producing.

    We have assayed various IPTG source, water quality source, but have had no success. we have also verified the presence of plasmids.

    Have anyone had any similar experience?

    Maryam Golshani · Pasteur Institute of Iran (IPI)

    Hi Carmen,

    1- Did you check all factors, rather than IPTG concentration, that influencing protein expression? Protein expression depends on various factors like: Temperature, Time of incubation after induction, OD of the culture at 600nm, culture media formulation, rpm of the incubator and inducer concentration.  Some proteins could be expressed in tempratures other than 37*C. Although the best time for adding inducer is when the medium reaches the proper OD600 (~0.4-0.6), we had a protein that expressed uppon induction in OD600 = 0.7. Additionally, sometimes your protein needs over night incubation to be expressed.

    2- Did you do Western blotting to check the induced bacterial lysate? Maybe, the protein has basal expression that could not be verified by SDS-PAGE.

    3- Please check the hydrophobicity of the protein sequence by bioinformatics tools. our experience shows sometimes proteins with hydrophobic N-terminal could not be expressed in vitro.

    4- If the protein is prokaryotic, try to use another source of gene for protein expression. We had the same problem with a bacterial protein. Since the protein was 100% conserved among the species, we tried to amplify the gene of interest from another species of the same genus. 

    Good luck!

  • Oliver Opatz added an answer in Extreme Environments:
    Does anyone have experience with an animal model in hypothermia?

    We would like to exchange experiences and maybe get some informations about your work. We ourselves only work with humans in extreme environments. But as the animal model extends your possibilities it would be interesting what kind of knowledge is transferable.

    Oliver Opatz · Charité Universitätsmedizin Berlin

    Thanks a lot!

  • Jaykov Foukzon added an answer in History of Mathematics:
    What is the origin and how do we explain the growth of mathematical concepts?

    A.N. Whitehead contended that the science of pure mathematics is the most original creation of the human spirit (Science and the modern world. 1948).

    Number and Geometry appear to be earliest mathematical concepts (see the attached diagram, where N = number, G = geometry). The concept of number has had a huge influence in astronomy, commerce and religion as well as other disciplines.   Geometry has had an enormous influence on agriculture (layout of fields, design of buildings, land surveys, measure, metrics) and philosophy (view of space, dimensionality, permanence vs. impermanence of form, continuity, betweeness, boundedness). Such concepts gradually emerged from a number of cultures in the Middle East, Greece, and in Asia (especially, India and China).  In his history of geometrical methods, J.L. Coolidge, 1940, observed that many mathematicians believed that analytic geometry sprang from the head of Descartes as did Athene from that of Zeus (p. 5).   The attached chart showing the influence of number and geometry on other subjects is incomplete (e.g., physics, chemistry, genetics, engineering, architecture are missing from the chart).


    The concept of a curve has its origin in antiquity and continues to contribute to growth of mathematics.  The attached chart traces the history of the concept of a curve (from R.L. Wilder, AMS talk, 1953).   The story of curvature can be traced back written records in Greece (geometry, Archimedes and others) and in Persia (algebra—Al-Jabr—from treatise by Muhammed ibn Musa al-Khwarizmi, 820 A.D., which originally meant restoration and completion).   See, e.g.:


     http://en.wikipedia.org/wiki/History_of_algebra and https://www.khanacademy.org/math/algebra/introduction-to- algebra/overview_hist_alg/v/origins-of-algebra



    Geog Cantor is credited with introducing the continuous curve concept.  The attached chart is incomplete and needs many more notes to make it more representative of what has happened since the introduction of geometry and algebra more than 20 centuries ago.   See, e.g.:


    http://www3.villanova.edu/maple/misc/history_of_curvature/k.htm and



    Jaykov Foukzon · Technion - Israel Institute of Technology

    >but this has a price : the objects are abstract, without any reference to the real world,

    By Gödel's completeness theorem  Con(PA) <-----> PA has an model MPA. But if this  model are abstract object, I. e. mathematical fantom  only, then  PA obviously must be inconsistent.

  • Oliver Opatz added an answer in Cooling:
    What kind of cooling devices do you use to cool patients after resuscitation? How about your experiences?

    If possible provide some critics like a pro and contra list!


    Oliver Opatz · Charité Universitätsmedizin Berlin

    thanks, what brand are the blankets. Is it possible to set a temperature or os it just on/off?

  • Adel Spotin added an answer in Toxocara:
    How can I make Toxocara larva from embryonated eggs of adult worm?

    How make Toxocara larava from embryonated eggs of adult worm?

    Adel Spotin · Tabriz University of Medical Sciences

    Thanks all

  • jean claude Dutailly added an answer in Theoretical Physics:
    Can Quantum 'Mechanical' Description of Physical Reality be considered Completed?

    Simplicity is the key to the interpretation of physics. Nothing more simple in the analysis than supposing the existence of some parameter "hidden," invisible and not measurable which is an integral part of a pair of photons and that tells at the time of their creation: "you are oriented east" or "you are oriented to the west. "This analysis requires us to introduce "hidden variables", a process which in physics is debatable, but allows in a very elegant way to explain everything in realistic terms. The pair of photons has its own objective reality that can describe them completely. Part of this reality is unknowable but never mind, the problem is only human, nature is safe.

    We have two options: 1) quantum mechanics is inherently probabilistic; 2) quantum mechanics is not inherently probabilistic, but deterministic. The first position is that of the so-called "Copenhagen interpretation", still very accredited by physicists, while the second was that of Einstein-Podolsky-Rosen (EPR) and of the "hidden variables". Subsequently, Bell showed that the hidden variables can not be there. John Bell in 1964 pointed the way for an experimental verification of the existence of hidden variables, but subsequent experiments, especially the French group of Alain Aspect, have shown the full validity of quantum mechanics.

    Then, the second theoretical position is no longer sustainable. Instead it is if we consider the fact that the "ontological materiality" turns out to be greater than the "physical". There are no additional variables that may enter into the physic calculation, but there are physical materials that physics fails to consider which have an impact on theorizing. These factors determine the overall behavior of matter which, therefore, appears inherently probabilistic. It can be said that Einstein was right: the hidden variables exist, only that they lurk outside of physics, in ontology.

    Many physicists (Einstein leading) have always refused that indetermination be an inherent feature of physical reality. Consequently, they preferred to assume that the description provided by quantum mechanics was simply incomplete. Their reasoning, in practice, consists in saying: even at the microscopic level physical reality continues to be deterministic, only that we can not know the exact values of the state variables and so we are forced to an indeterministic description. To explain this failure many proponents of determinism (starting from Einstein himself) introduced the so-called "hidden variables". At the microscopic level, there would be some factor that is not yet known which would prevent us from a deterministic description. The moment we knew, we could provide a description of these factors completely deterministic

    For many years the debate between the advocates of the hidden variables and the promoters of intrinsic indeterminism remained on a purely metaphysical level. In 1964, however, the physicist J.S. Bell derived a famous inequality (Bell's theorem) that allowed to transfer experimentally what until then had been a metaphysical discussion. Such inequality, in practice, led us to expect different experimental results depending on whether had been true the hypothesis of hidden variables (at least limited to the so-called "local theories") or not.

    Now, the Heisenberg principle would not only establish our inability to learn at the same time the values ​​of the position and momentum of a particle. These values are established, before a measurement be made, they are absolutely and inherently indeterminate.

    Einstein's objections to quantum mechanics made sense because he was perfectly aware that quantum mechanics is incompatible with determinism. However, his views obstinately deterministic and his attempts to defend them (hidden variables) have not stood the test of facts.

    The microscopic reality is inherently indeterminate. However, what is surprising is that the macroscopic reality is instead largely deterministic. To explain this apparent contradiction is a fascinating challenge in theoretical physics. An interesting attempt at a solution appears that provided by three Italian physicists G. Ghirardi, A. Rimini and. T. Weber (in Physical Review D 34, 470, 1986).

    So, in this context it became obvious that the description of the states of a physical system offered by quantum mechanics was incomplete and that such an incompleteness was responsible for the indeterministic character of the theory. In other words, it has been assumed that quantum mechanics is indeterministic only because our level of knowledge does not put us in a position to "see" some additional variable, able to "complete" the description of the physical system provided by quantum mechanics. According to this conjecture, if we were able to identify these new variables, currently "hidden", we would recuperate a level of description deeper than the quantum level and at that level determinism could be recovered. "

    In fact, the enigma of the "hidden variables" was not solved by a logical-deductive approach, as Popper might have wished, or was it only partially.

    As already said, “in 1964 the issue was a crucial turning point: J. Bell showed that for a large family of theories and hidden variables, the so-called local theories, it is impossible to reproduce with media operations on hidden variables all the predictions of quantum mechanics. "" the result of Bell had the great merit of showing on the experimental ground the theme of possible deterministic completions of quantum mechanics, and a great interest aroused for the realization of experiments sensitive to discrepancies between the predictions of quantum mechanics and that of the local theories of hidden variables . "(Enrico Beltrametti)

    In 1981, Alain Aspect was able to realize the first of a series of experiments of high quality. In practice, the experiment showed that Einstein had been wrong in suggesting the idea of hidden variables.

    As for Popper, we could say that he lost a game: the one with LQ,

    Criticism of Popper was wrong from a logical point of view, but in many ways it had some basis. Popper did not want to admit a weakness of logic explicit in theory LQ. For Popper's logic was to remain an ‘a priori’ science, having as main feature the absolute independence from any content. Therefore, he refused to consider the possibility of choosing logics different from the logic, most suitable than this to the empirical character of particular situations.

    Already in the Logic of Scientific Discovery, which was finished in 1934, then prior to the writing of Birkhoff and von Neumann, Popper anticipated: "... replacing the word" true with "the word" likely "and the word" false  with "the word" unlikely ", nothing is gained.

    However Popper earned another no less important point. The revolutionary discovery of Bell and Aspect was not from a pure inductivism, but from experiments carried out in the light of a theory already formulated ‘a priori’, then from a hypothesis to be subjected to strict scrutiny, identifying the elements and data that could refute it. At least on this ground, Popper took an important rematch.

    At the time of the article in Einstein's death, the controversy was still strong and "philosophical" issues had a great weight, so much so that an American physicist was the victim of McCarthyism and lost his job for supporting a deterministic model with hidden variables. Today we tend to minimize the importance of our imperfect knowledge on the subject; theories are used as they are reaping the fruits without worrying about a coherent understanding of the underlying laws. Most physicists do not interpret more the principle of indeterminism  in a metaphysical way. It is considered as a simple impossibility of knowing at the same time position and momentum of the particles in a system still felt completely deterministic. After all, beyond the supposed wave-particle duality, also in the macroscopic world there is a kind of uncertainty: for example, I can not measure my speed with accuracy higher than my reaction time to press the button on the timer.

    jean claude Dutailly

    Dear Sofia,

    Actually I have a comprehensive, consistent interpretation of QM, that you can find in my book Mathematics in Physics on this site, and there is an explanation of the entanglement... But all the narratives about Bell's theorem, hidden variables are usually so much embedded in the concepts of quantum physics that, from my point of view, there is little to add, and I believe that experts such as Charles Francis have given what has to be said on this topic. There has been hundreds of thousands of academics who have worked on these issues, they are paid for that, not me. I bring my contribution, if the people like it, the better, if not, so bad for them.

    The explanation of entanglement is actually very simple, it does not need any special particle, dimension, physical phenomena, ... Have a look, this part is short.


  • Valter Ström added an answer in Magnetostriction:
    Can I use a normal laboratory solenoid to investigate magnetostriction in mild steel using a strain gauge by measuring change in length?

    I am currently in my final year of bachelors and my research involves investigating the effect of an externally applied magnetic field on the young's modulus of a bar of mild steel. The problem is, I have not been able to get a solenoid to produce the magnetic field to investigate this phenomenon. My question is:

    1) will a normal laboratory solenoid allow magnetostriction in mild steel that can be measured using a strain gauge in terms of change in length of the specimen

    2) if not, what instrument can I use in order to produce the necessary magnetic field for this experiment. Where can I buy it.

    Thank you.

    Valter Ström · KTH Royal Institute of Technology

    Dear Huzaifa,

    usually magnetostriction is a pretty tiny effect, (it was a big hype when the Terfenol came 20 ys ago with so called giant magnetostriction) and I believe mild steel is in this category. Moreover, mild steel is certainly a soft magnetic material, and so would require only a modest field to reach saturation. Can you control the geometry of the sample? If so, a slender piece with a lengh/width (or whatever) ratio >10 would not need more than say of the order 10kA/m.... Possible with a solenoid even without an iron core.

    The tricky part is probably to quantify the elongation. One suggestion might be to use an AC field and detect the oscillating length at twice the driving frequency. This is due to the fact that magnetostriction does not sense in which direction the magnetization goes, right?

    How to detect this movement? I would refrain from a strain-gauge. Rather an optical method. Maybe an off the shelf little electronic LED-phototransistor device used in reading the presence of cards etc.

    This was just a few thoughts about your project!


  • Cristina Buga asked a question in Public Procurement:
    Does anyone know how to find statistics on public procurement? Which portion of total public procurement is allocated to imports?


    Could anyone help me to find data on international public procurement (on a global scale). I want to estimate what part of public procurement is dedicated to imports.

    thanck you very much,

  • Kenneth M Towe added an answer in Food Biochemistry:
    Is there a correlation between antioxidant activity and mineral content?

    Is there any correlation between antioxidant activity and Mineral content in food material?

  • Robert Anthony Watson added an answer in Sun:
    What amount of energy is required, in the form of graviton release by the Sun, to keep Jupiter in its orbit around the Sun?

    What is the amount of energy released by the Sun per second, in the form of the energy of the gravitons (in Watts), required to keep Juipter in orbit.

    Anwers not required are the potential energy or forces acting on Jupiter. 

    Robert Anthony Watson · The University of Manchester

    A quantised version of gravity proposes a exchange of virtual gravitons underlies the gravitational force, so there's no net energy radiated.

  • AHMED ALBARRAM added an answer in Displacement:
    How can I deal with the velocity option in boundary condition ?

    I am modeling a push-up sample regarding the composite beam. I need to apply a magnitude of load without inserting a specific amount of load or even displacement, and eventually come up with the reaction force and displacement.

    I think the way to deal with this is using the Velocity/Angular velocity option in the boundary condition. How can I deal with this option.

    Note: the sample I am dealing with is attached with this message

    AHMED ALBARRAM · University of East London

    Dear Sina

    Riks method does not help that much to achieve an accurate results due to dealing with very complicated non-linear materials, besides I have read some papers related to my work that do not recommend to use Riks method. So the best way is employing the dynamic analysis.


  • Sascha Rohn added an answer in Plant Extracts:
    Is there a method for tannin removal?

    Is it possible that tannin might get extracted during an alkali extraction of a plant material? What is the best method of removal of tannin from an alkali plant extract?

    Sascha Rohn · University of Hamburg

    With regard to Md Kahlid suggestion: This works quite well. However, there are some countries where the use of lead acetate is absolutely forbidden, because of its cytotoxicty....you have to think over if you want to be a nobel laureate or being healthy reseracher throughout your whole life...

  • Philip Barlow added an answer in Grassland:
    Can someone recommend proven deep rooted perennial grasses that are drought tolerant and suitable for the rehabilitation of Mediterranean grasslands?

    Species can be native or introduced

    Philip Barlow · Bio Soil & Crop Ltd New Zealand

    I do not have the exact answer to your question, but I know where to look: The New Zealand Grasslands Association  has a wealth of research information and much of it relating to the summer dry East Coast region.  For example there is the 200 page proceedings of the Symposium "Legumes for Dryland Pasture" Lincoln University 2003 [ISSN 01108581 ISBN 0-864761570] A second example Proceedings of the NZGA 1999 The effect of pasture species on Lamb performance in Dryland systems. page 23-29 http://www.grassland.org.nz

  • Rashko Georgiev added an answer in Materials Science and Engineering:
    Why does heat transfer coefficient increase with velocity?

    I have seen some graphs in which heat transfer coefficient increases with the velocity, can anyone tell me that how can I mathematically relate the heat transfer coefficient with the velocity of fluid?

    Rashko Georgiev · Trakia University

    The coefficient of heat transfer depends on the speed of flow. Depending on the magnitude of speed using various kriteria equations.

  • Boellemis Boellemis asked a question in Nucleic Acids:
    Acridine orange - is RNA more acidic than DNA? And why?

    I am doing some research on acridine orange (AO).

    I've found out that the emission wavelength of AO depends on whether it binds to double-stranded or single-stranded nucleic acids (DNA/RNA), due to that AO aggregates on single-stranded nucleic acids.

    However, I've also read that AO emission wavelength (thus, aggregation) depends on pH. So how come there is a difference in emission spectra (aggregation) when binding double-stranded nucleic acids (mostly DNA but can also be rRNA, tRNA) compared to single-stranded nucleic acids (RNA, sometimes DNA)?
    Is it because the single-stranded structure is "more acidic" than the double-stranded structure? I know there is an extra hydroxyl group on ribose (RNA), but since AO binds single-stranded RNA as well as DNA I guess I can't blame an extra hydroxyl for making single-stranded nucleic acids (RNA and DNA) "more acidic" as DNA doesn't have that extra hydroxyl. So what is it that makes single-stranded nucleic acids "more acidic" than double-stranded nucleic acids?

    Looking for some serious help to make me understand..

  • Diogo Fonseca-Pereira added an answer in Flow Cytometry:
    Do I need isolate CD4 positive cells by MACS first for IL-22 intracellular staining in mouse MLN lymphocytes?

    Recently I'm working on detecting IL22-producing CD4 positive cells in mouse MLN by flow cytometry. However, after using PMA/ionomycin plus GolgiPlug neither 4 hrs or 6 hrs culture, IL-22 positive cells population were still too low to analyse (about 0.5%~3%). Should I need isolate CD4 positive cells by MACS first or are there some tricks to do this experiment?


    Diogo Fonseca-Pereira · Instituto de Medicina Molecular

    Hi, are you using naive animals or after some infection? The expression of IL-22 is normally low, the better place to take IL-22+ cells would be the intestine. Nevertheless instead of stimulating with PMA/ionomycin, you can try to use 4 to 6 h of stimulation with IL-23 plus a transport inhibitor, since IL-23 stimulates IL-22 production (some people do this in the lab). Good luck =)

  • Fausto Sánchez-Muñoz added an answer in microRNA:
    How do I normalize exosomal miRNA expression from serum/plasma samples in RT-qPCR assay?

    Hello everyone:

    I am looking forward to analyze the differential composition of exosomal miRNA for a follow-up study. I would like to know which is the best approach for the normalization of the data obtained in the RT-qPCR:

    - Should I add an spike-in control (cel-miR-39) during the extraction of the miRNA?

    - Is it better to screen for stable exosomal miRNA in all my samples?



    Fausto Sánchez-Muñoz · Instituto Nacional de Cardiología

    Add an spike-in control (cel-miR-39) during the extraction, and/or bacterial ribosomal RNAs (i use from Roche).

    We are currently using both.

  • Kenneth M Towe added an answer in Climate Modeling:
    Is there a simple way to represent future climate variability without using dynamic or statistical downscaling techniques?

    I wanted to represent future climate variability due to El-Nino Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO), without applying the dynamical or statistical down-scaling frameworks? The aim is to assess the impact of future climate variability on water balance components using watershed hydrological model. Could someone help me if there is a simple way to represent this in hydrological model?

    Thank you in advance.