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  • Emmanuel Planel added an answer in Alzheimer's Disease:
    Question about role of GSK-3 in AD?
    Which form of GSK-3 is having much role in AD pathology? as both(alpha n beta) are widely expressed in brain and having vital function. and why?
    With GSK-3 exploration in AD which pathway is predominant? Wnt signaling which is wingless intigration that can stabilise beta-catanin or any other ralevant pathway responsible for tau hyperphosphorylation?
    whether beta-catanin stabilisation will have significant role in AD patho... as it is mainly concern with oncogenic pathway?
    For screening of AD with GSK-3 target which standard GSK-3 inhibitor is worthfull? as til now no such drug is approved for AD n so many molecules are in phase trials.

    any one can explore this questions.......

    thank you....
    Emmanuel Planel

    There is no direct proof that either GSK3beta or alpha are implicated in AD. In fact, nobody has proven beyond doubt that GSK3 is overactivated in AD brains (see this excellent review; http://www.ncbi.nlm.nih.gov/pubmed/18088381). The problem stems from the fact that the phosphorylation of Ser9 residue, which is the best indicator of GSK3 activity, is extremely labile and will disappear within minutes after death. So it's impossible to have an idea of GSK3 activity in post-mortem human brains. Another problem is the large number of substrates of GSK3, both in the brain and the periphery, increasing the possibility of serious side effects with drug targeting it. That's why no inhibitor of GSK3 is approved in AD, and why most pharmas have abandoned their efforts to develop one.

  • Yohannes Mehari added an answer in Hela Cells:
    HeLa cells are not sticking to coverslip?

    Hello guys

    Well I am having problem with my HeLa S3 cells. I do not know why they are not sticking to the coverslip when I seed them in a 6 well plate. I am seeding 5 x 10*5 to 10*6 cells in a 2 ml RPMI supplemented with 10% FBS. After few days of incubation, I can see some cells attached on the coverslip but they do not look happy and stretched as they usually do.

    I can also see cells sticking happily to the well surface but not to the coverslip. 

    Anyone had this problem before.

    Thanks in advance for your support. 

    Yohannes Mehari


    Thanks for your prompt response. So far I have been using regular CS sterilized and cleaned with alcohol and yet again sterilized with UV and then rinsed with culture media to remove and alcohol residues. I guess I will have to clean them further with detergent and acid. It worked fine with my U937 monocytes like cell lines. 

    Keep you posted with the results.



  • Narges Mavedat asked a question in Fourier Series:
    What is gibbs phenomenon?

    In mathematics, the Gibbs phenomenon, discovered by Henry Wilbraham (1848) and rediscovered by J. Willard Gibbs (1899),[2] is the peculiar manner in which the Fourier series of a piecewise continuously differentiable periodic function behaves at a jump discontinuity

  • Becky Ingham-Broomfield added an answer in Nurses:
    As part of the assessment of a deteriorating patient, how long should it take for a qualified nurse to read the results of an ECG?

    I intend to measure nurses' competence in interpreting an ECG and their ability to quickly recognise a potentially life-threatening arrhythmia. In order to accurately do so, I am going to set up a series of scenarios with an associated ECG that the candidates will have to interpret.

    As these scenarios will be focused on the assessment of an acutely-ill patient, I was wondering if anybody knew whether there is a consensus on the amount of time nurses should take to determine the existence of a life-threatening arrhythmia.

    How long do you think it should take a qualified nurse to interpret an ECG? (not taking into consideration the amount of time needed for the recording process)

    Thanks in advance.

    Becky Ingham-Broomfield

    Life threatening arrythmias should be quickly interpreted - VT, asystole and VF should be apparent in seconds. The scenarios would potentially have nurses pre-determining that you were going to show them something life threatening so they are already pre warned. In a real situation it may take a few seconds to realise something isn't right then a few more to actually decode then respond. A rhythm strip is different to an ECG ie 12 lead, so the terms need to be clarified. Best wishes for your research.

  • Bradford D Martin added an answer in Ornamental Plants:
    Can anyone help me identify this ornamental plant?

    This plant is successfully cultivated in Jordan as ornamental plant, but I am unable to find it as a species in the local or neighboring floras.

    + 2 more attachments

    Bradford D Martin

    Brachychiton populneus (Australian bottle tree) of the Malvaceae or Sterculiaceae, depending on a more inclusive or exclusive classification.

  • Abbas Rahdar asked a question in Microemulsions:
    What is effect of oil (continuous phase ) on the flouresence intensity in water-in-oil microemulsion?

    what is effect of oil (continuous phase ) on the flouresence intensity in water-in-oil microemulsion?

  • Paul E Zollinger added an answer in Knee Osteoarthritis:
    Is there any placebo similar to topical diclofenac gel?

    In studies evaluating efficacy of topical diclofenac gel for different joint pains (such as knee osteoarthritis) we need a placebo similar to diclofenac gel (its viscosity and odor).

    Paul E Zollinger

    You could use cetomacrogol-gel as a placebo gel, but it's not wise to expose the patients to both at the same time.

  • Agnieszka Barbara Najda added an answer in Chemicals:
    I need Nagila savita (kalwaji) chemical sturctre?

    i need nagila savita excat strcutre. i will try many time but not fine the excat strucutre. If someone have plz send me.

    Agnieszka Barbara Najda

    What kind of extract it?
    Is that supposed to be dry extract of nasin or extract liquid, in which solvent?

  • Jose Duguet asked a question in Antibiotic Resistance:
    Does anyone worked with Sure Vector Core kit for yeast expression with other selection, no LEU?

    My quiestion is the following, if I do not want to work with an auxotrophic strain, how can I design and/or get a XP2 expansion module for antibiotic resistance marker, like NeoR with a yeast promoter?

    Hope someone could help me. 

    Kind regards

  • J. W. Zartha asked a question in Innovation:
    Can anyone recommend studies about innovation strategies in companies?

    The emphasis of the question is about formulation and implementation of  innovation strategies

  • Ezequiel Marron Fernandez de Velasco added an answer in Cloning Vector:
    Anyone has the pcDNA3.1.N-HA (empty) vector?

    Dear all,

    does anyone (in Germany) has the pcDNA3.1 N-HA vector (empty) and could provide me a drop? Thank you!


    Ezequiel Marron Fernandez de Velasco

    Hi Laura,

    I wont be able to provide you the plasmid however it would be very easy, if you can not find it, to introduce the HA tag in your protein by a simple PCR amplification of your gene of interest or if you already have it in a pcDNA3 type vector (but without HA) by direct mutagenesis.


  • Kazeem Adepoju added an answer in Analytical Modeling:
    Experimental vs analytical: how do I approach statistics?

    I have a set of experimental data (EXP) which I have fitted with two analytical models (AN1 & AN2).

    In order to estimate the precision and accuracy of both analytical models I can study statistics of the ratios EXP/AN1 and EXP/AN2 or AN1/EXP and AN2/EXP.

    Well, the point is that statistics of such ratios are not coincident.

    I see that many researchers adopt the first approach when I istinctively would go for the second because I can compare two different analytical models by normalizing them with respect to the same experimental variable.

    Is there anybody who can help me out with this?


    Kazeem Adepoju

    Please ensure that well known model selection criteria are used in comparing your models.Also note that there is a difference between precision and accuracy.

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub

    I don't think we experience time. I think we experience progression and succession and change and call it the passage of time.

  • Daniel Alejandro Perez added an answer in Taqman:
    Any suggestions about a late amplification at ~35 cycles, with RT PCR?


    I am seeing late amplification at about 35 cycles. Also, I believe that the difference in expression curves is due to not having normalized my templates (not certain, could be completely wrong).. I did not have a Qubit to measure some of the cDNA controls that were made before my time in the lab. I was able to normalize the other cDNA samples at the RNA level before reverse transcriptase.. 

    Ct values range from 26-35 (not sure if this helps for this question) 

    Image attached. Please help :) thank you! 

    P.S. -- using SensiFast, Hi-Rox Probe kit from Bioline with TaqMan gene expression pre-designed probes and beta-actin endogenous controls. 

    Cycling conditions: 1X at 95C for 2 minutes, (95C for 10s, 65C for 30s)X40 

    Daniel Alejandro Perez

    Thank you everyone for your very helpful insight.. 

    Alfonso, muchismas gracias. Voy a revisar cada paso del proceso y compartir tus sugerencias con mi colega y aplicarlas con mi proxima qPCR. Espanol es mi primer lenguaje pero no lo aplico seguido con las ciencias moleculares, mi colega es de Mexico y vamos a estudiar tu respuesta en mas detalle :) 

    Augusta -- Many thanks for your insight, I did have negative controls and the output I got was "undetermined" Ct values which I take as no expression and therefore no contaminants. What do you think? The issue with the template is two-fold, although I can solve one. The first and most important factor is the source of my RNA -- it is post-mortem myocardium. Already I expect a very low yield of RNA. The second is that the control cDNA that I am using was created before I joined this lab -- I have no record of how much RNA was used to create the cDNA and the lab is only equipped with a nanoquant, for which I don't have a valid blank for specking the cDNA. I am fairly confident with the cDNA that I made because I normalized at the RNA level.. 

    Pietro -- thank you for your thorough walk through.. I expect low mRNA because I am purifying from post-mortem myocardium, do you think I'd still see amplification of actin a lot sooner with low yield due to the fact that the tissues were not flash frozen immediately? What are your thoughts?..  Also, I went with Bio Line because I had used them before for conventional PCR, thought they'd be great for RT PCR as well. I'd like to hope I didn't waste funds on their stuff so I will try trouble shooting as much as I can before I order new stuff from LifeTech. 

    Thank you all so much! 

  • Kamesh Regmi added an answer in Molecular Biological Techniques:
    Where can I order aminomethylenediphosphonate (AMDP)?

    AMDP is a specific inhibitor of proton pyrophosphatase. No vendor seems to be selling this chemical. Any help will be highly appreciated.

    Kamesh Regmi

    Unfortunately, Sigma doesn't have it.

  • Seda Tht added an answer in Triacetin:
    Convert to Units in Lipolytic activity assay?

    I have assayed the lipolytic activity of lactic acid bacteria isolated from olives by spectrophotometric method. I used lipase from porcine (Sigma) to generate a standard curve.  I tested bacteria but I can't convert the results from microgram to Units.

    The lipase box says following:

    Lipase from porcine pancreas
    Type II, 100-500 units/mg protein (using olive oil (30 min incubation)), 30-90 units/mg protein (using triacetin)

    So, 1 microgram/miligram = How many Units? I couldn't calculate this. Please help.

    Seda Tht

    thank you so much, I guess I can not express. I will continue to research. Thank you for help.

    Best regards...

  • Ezequiel Marron Fernandez de Velasco added an answer in Patch Clamp:
    What is the reason that cultured cells die during gigaseal formation?

    We want to patch clamp primary cardiomyocytes from zebrafish according to the protocol described by Brette et al. 2008. 

    The isolated cells look fine but during gigaseal formation the cells immediately shrink and die.

    Does anyone have an idea why this problem occurs?

    Ezequiel Marron Fernandez de Velasco

    Hi Georg,

    the most likely explanation is that during the seal formation you actually "break in", that is you go to whole cell configuration. Since the seal is not totally formed yet you can not really clamp the cell membrane voltage and the influx of calcium from the bath solution immediately produces the collapse of the cell due to contraction.

    I would recommend playing with the amount of pressure, both positive, while approaching the cell, and negative, once you are trying to form a seal. I would also try different pipette sizes until you find the one that allows you to form a stable gigaseal that afterwards you can use to go whole cell while keeping the cell clamped.

    Of course your bath and pipette solutions will play an important role in establishing a good gigaseal and there are many papers around that you can use to compare compositions.

    Hope this helps,


  • J. W. Zartha asked a question in Innovation:
    What are the stages of the formulation of an innovation strategy?
    • This question is related to "Innovation Strategies" in companies
  • Suliman . added an answer in Butanols:
    Which one is the best solvent to extraction bioavailable fractions of pesticides from soils, butanol or methanol or hot water?

    please help me out? which one is the best solvent to extraction bioavailable fractions of pesticides from soils, butanol or methanol or hot water?

    and why?

    Suliman .

    thank you

  • Gustavo Plotnikow added an answer in Pulmonology:
    How frequently do you change the breathing circle ( unless there is an infected patient)

    There is little literature on this issue and practiced differ tremendously from one hospital to another. Some hospitals change the circuits Shen they are broken (.yes, some people are poor), most on a weekly basis, and some even after each patient. It is a very grey zone. and a permanent source of useless waste.

    Gustavo Plotnikow

    Dear Paul, we don't change the breathing circuits routinely. In fact, the standard is not changed or at least do that the least possible, and the guidelines (attached files) recommend this. I don't see the need to do this routinely.

    Kind regards

    Gustavo (Buenos Aires, Argentina)

  • Thomas Trezza added an answer in Heat Capacity:
    Heat capacity values from graph?

    How to calculate the heat capacity value from DSC graph (i.e. J/kG- K versus temperature (K)?

    Thomas Trezza

    Mathematically it is the heat flow divided by the heating rate. Here are links to two papers that explaina procedure:



  • J. W. Zartha asked a question in Delphi Method:
    ¿What are the main problems of the Delphi method?

    Problems related to the application of the method

  • Romil Aggarwal asked a question in Flash:
    Which techniques/papers should I follow to implement an anti-glare(flash removal) filter for images?

    I want to implement a system(a filter) that would be able to remove flash from an image. So basically an anti-glare system. Which techniques should I use or which paper should I follow so as to accomplish this task.

  • Kashif Nawaz added an answer in Nucleotides:
    What is the best computer program for finding sequence motifs in an RNA sequence?


    I'm looking to perform a search of a specific RNA sequence for a two-part motif, composed of a hairpin followed by a U-tract. So, I'm trying to find a program that can scan the RNA sequence, identify regions of >80% enrichment of U's between 7-10 nucleotides in length, and then search upstream from those elements for sequences likely to form stem loops of a certain length or longer. Can anybody suggest such a program?

    Kashif Nawaz

    Convert your RNA to cDNA then submit NCBI Domain search.

  • S. Mosa asked a question in Geometry:
    What is the best introductory reference on Galilean geometry?

    i need to understand the definition of the Galilean space.

  • Peter C Ambe asked a question in Inflammation:
    Are you familiar with percutaneous cholecystostomy (gallbladder drainage) for the management of severe cholecystitis?

    Acute cholecystitis (AC) is frequently encountered in daily clinical practice. Since its publication in 2007 and the update in 2013, the Tokyo guidelines (TK 13) for the diagnosis and management of acute cholangitis and acute cholecystitis rapidly gained popularity. Besides defining diagnostic criteria, the TK 13 also enable a classification of acute cholecystitis in three severity grades. Grade I describes a mild form of inflammation, grade II describes a moderate gallbladder inflammation, while grade III corresponds to severe gallbladder inflammation in association with organ dysfunction. Laparoscopic cholecystectomy l (LC) is recommended for patients with grade I, a portion of patients with grade II should undergo LC in centers with expertise while all other patients (the rest of grade II and all grade III patients) should be managed via percutaneous cholecystostomy (PC).

    A major problem with AC is the heterogeneity of clinical presentation! This makes it difficult to standardize treatment options.  The treatment algorithm suggested in the TG13 cannot be universal! Besides, the benefit of PC in the management of severely ill patients with AC could not be established in a number of meta analyses. 

    The greatest weakness of the TK13 in my opinion is the failure to incorporate patient - dependent factors.  Therefore my primary question is how do you choose candidates for PC? Second, do you adhere to the TG13? Third, how do you judge the current evidence on PC. 

  • J. W. Zartha asked a question in Foresight Studies:
    ¿Where I can obtain applications of MICMAC in foresight studies?

    Especially applications in companies

  • Ihor Yaskal added an answer in International Relations:
    Hello everyone. What is the relationship between capitalism and world government theory?

    Political science, International relations

    Ihor Yaskal

    Yoshinori Shiozawa, you welcome!

  • Emmanuel Planel added an answer in Amyloid:
    Which is the most pathophysiologically accurate transgenic mouse model of Alzheimer disease?

    I would like to examine the relationship between amyloid deposition and tau hyperphosphorylation. Do any of the available transgenic mouse models of AD develop amyloid pathology and THEN tau tangles? Are there any mouse models that develop amyloid plaques primarily in limbic/striatal regions without much plaque in primary sensorimotor areas (the way it is distributed in human disease)? Are there any transgenic animals where only amyloid-related genes are manipulated but which develop tau-tangle pathology anyway? 

    Emmanuel Planel

    Hello Fred, to answer your comment, I don't object to APP mutations in mouse models of AD because some APP mutations do cause familial AD. I'm less enthusiastic about using models with tau mutations because tau mutations do not cause AD, they cause FTDP-17. When you actually compare AD brains with FTDP-17 brains, there is much less tau pathology in the latter, despite more neuronal loss (http://www.ncbi.nlm.nih.gov/pubmed/16866983). So it seems that, in humans, tau mutations cause changes in cellular function so lethal that neuronal death occurs before much tau can be detoxified as tangles like in AD (discussed here: http://www.ncbi.nlm.nih.gov/pubmed/18688094). Thus, some of the results obtained with mutated tau mouse models should be carefully considered, as they might be not relevant to AD. That said, they are still an invaluable tool to study tau pathology in preclinical studies.

    And you are right, not all Beyreuthers have the Beyreuther mutation, as not all Van Leuvens live in Leuven ;-)

  • Ahmad Abd el azeem added an answer in Stem Cell Isolation:
    Can getting stem cells from fetus harm its growth?

    we know that there are stem cells that make our body in our very first months,the stem cells can make different organs of our body and if we have these cells we can help body cure some disease.these stem cells are faster than adult stem cell.but as the fetus needs these stem cells to form the body, isn't it harmful to take these cells?

    Ahmad Abd el azeem

    Dear Zahra,

    Actually cord blood ,amniotic fluid are sources for very young adult stem cells that can be taken by the end of pregnancy ,but if you mean by your question real embryonic stem cells even early before 3 germ layers ,this can be only practiced in case of artificial fertilization like "IVF" babies and usually practiced for genetic diseases surveying before implanting the fertilized ova  ,to overcome all of this scientist have been studying what makes a stem cell a master cell, this had lead to a method to induce adult cells to de-differentiate into pluripotent stem cells the tech. now called IPS or induced pluripotent stem cells, with many methodologies and a concurrent clinical study in kobe medical center ,japan,