Adelaeda Barrera added an answer:Has anybody worked on SKOV-3 cell lines induced xenograft mouse model using CD1 NUDE mice?Can anybody suggest about cell number/animal as well as time consumption to grow tumors up to palpable limit?
Hello, by any chance does anyone know if SKOV-3 cell lines can produce ascites when injected to nu/nu mice?Following
Ifeoma Obidike Ezenyi added an answer:How can I reduce mortality in STZ induced type II diabetes in wistar rats?
Dose injected - STZ 60mg/kg I.P
Strain: wistar albino female rats
Bwt-120 to 150g
have given 5%glucose 2hr after STZ induction for 24hours
after 3 days- diabetic rats - 19 out of 30
after 7 days-
mortality observed -12 out of 19 ie. 7 rats alive
Also increase sucrose concentration to 10%w/vFollowing
Stanton de Riel added an answer:How to lower the pH of a furosemide buffer?
I just prepare 50 mg/ml furosemide in NaOH, then try to adjust pH with HCL. We hope the pH for this buffer is around 7, well we also accept 8 or 9. however, when pH drop a little bit lower than 10, many white furosemide was coming out and didn't dissove any more. and pH 10 is too high for our animal study. Is there any buffer I can try for prepare furosemide and let it pH become lower?
Looks like the furosemide molecule has several sites that can protonate/deprotonate -- your problem is likely to be that at pH 7 it's (functionally) neutral, hence not very soluble (the carboxylate will be deprotonated, but the secondary amine will be protonated, hence net neutral). You might try chelating it with a cyclodextrin. You can't cheat nature on pH issues, really. Depending on the administration route, could you use a co-solvent to increase solubility, perhaps, or if slower release is acceptable, load it as a suspension (by gavage, or subcutaneous depot injection)?Following
Lana Krestetska added an answer:Is there any knowledge in the litterature that Salmonella Typhimurium might be responsible for dizziness?
I'm working with Salmonella enterice serovar Typhimurium and when I orally infect mice, I observe 10% of mice having strong dizziness. This bacteria is known to infect systemic tissues such as mesenteric lymph nodes, peyer's patches, spleen and liver but what about the dizziness phenotype? Is Salmonella able to infect the internal ear? Or is there any other explanation for this?
Many thanks in advance for your help!
exaggerated lean to one side of the body and longitudinal spinning and rotary motion? http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1925087/Following
Imtiyaz Rather added an answer:Is anyone doing research on coumarin, or 7-hydroxycoumarin in the management of lymphedema?
Earlier research on coumarin showed very promising results, but some of the in vivo studies using rodents showed toxicity, which was discovered to be a metabolic pathway that is not usual in humans. But the compound was taken off the market in a number of countries, which is a real shame since it is one of the few and only pharmacological approaches that has shown success in reducing protein accumulation. If you are doing research in this area, please contact me.
Elaine Weil, NP
Coumarin and 7-hydroxycoumarin acts as anti coagulant and can definitely be a choice in treating lymphedema.Following
Adam L Vanwert added an answer:Any tips/alternatives for mouse tail vein AAV injections?
I've been attempting some mouse tail vein injections and seem to have trouble with consistency. Ultimately I would like to deliver viral vectors systemically.
Any tips for mouse restraint? (They of course jump from the stick and I lose my vessel.)
Are there simpler alternative sites for IV injection or other modes of systemic delivery that might serve my purpose?
Are there any syringe/needle sizes that seem to work better?
Please keep in mind that intraperitoneally injected substances will go to the liver via the portal vein prior to the systemic circulation. This may significantly reduce the systemic availability. I would continue trying the tail vein. It's just a matter of practice until you get good or at least good enough.
Ryan, I think IP injection for infecting enteric nerves makes some sense. Remember, the enteric nervous system is covered by cell layers. The myenteric plexus is covered by the longitudinal muscle, and the submucosal plexus is covered by the longitudinal and circular muscle.
Ryan, you might want to consider that the capillaries in the enteric wall are buried under the muscle layers. Therefore, it might be more efffective to get the virus in a proximal artery (right before the mesenteric vessels) so it goes into the intestinal wall in a high concentration. It may then diffuse out of the capillaries. I actually have no idea how large the virus particles are. Perhaps they don't cross capillary pores at all.Following
Lasse Giil added an answer:How can I get functional analyses of antibodies to GPCR for a good price?
We are studying the pathophysiology og autoantibodies to GPCR that we induce in animal models. In addition to looking at the histological endpoints, we would like to purify the IgG from the animals and get dose-response curves for individual animals and compare, and if possible by price, charcterize their functionality (and not just titers we get) further. I have contacted several drug-development companies. They will do it, but at a steep price. Are there any academic GPCR service lab. that have analytical services? I have not been able to find one. We got nothing in-house and the time and sallary spendt developing will be much more then the drug-developing companies charge. Thanks for potential response.
Thank you Markus!
I would like to look at activation of the second messenger, or any other version of confirmation of GPCR activation and ability to create a dose-response curve (some use arrestin, some use IC Calcium, (euroscreen/discoverX/eurofits). We want to look at anti-AT1R and anti-beta1.
Would love to use the human version, but we only have biobank material (With longitudinal data), so we dont want to spend alot of the serum, as its used by many other researchers.
We were going to use polyclonal antibodies, because we are looking at their ability to cause pathology and polyclonals more "Natural", even though raising them in Rabbits is far from ideal. The peptide immunization protocol is well known and has been used in several other studies. We want to get "dose-response" curves, as part of mapping their pathophysiological pontential.
Purification of the human forms will be a next step, but because of time/funding, we cannot do that now.Following
Geert C. Mudde added an answer:Does anybody have experience with the use of gemcitabine (Gemzar or a generic product) in non human primates? What would be the correct dose?
We are planning a chemo+vaccination combination study in NHP to mimic potential use in pancreatic cancer patients. The human clinical dose of gemcitabin is 1000mg/m2.
Txs a lot!Following
Alan H Fairlamb added an answer:Do you foresee that human-induced-pluripotent-stem-cells generated human tissue will be able to replace animal models in new drug discovery R&D?
Number of reports recently, where hiPSCs were used for generating various human tissues, have received a lot of media publicity. Of course, the scientific merit and the potential implications are enormous.. One report in Cell-October, 2014 on the Generation of Functional Human Pancreatic β Cells In Vitro (www.cell.com/abstract/S0092-8674(14)01228-8) from Prof. Melton lab at Harvard Stem Cell Institute is a game changer not just for drug discovery, but also in "hopefully curing" diabetes? Another in March 2015, from Prof. Healy lab, UC-Berkeley, on Human iPSC-based Cardiac Microphysiological System For Drug Screening Applications in Nature Press journal-Scientific Reports (www.ncbi.nlm.nih.gov/pubmed/25748532) for bio-engineering of 3D heart....
Can hiPSCs-generated human tissues and system biology software programs replace animal studies, mimic drug metabolism and articulate disease profiling? Can we decipher Toxicogenomics and Pharmacogenomics using these tissues, and extrapolate these data sets to predict at least the SAFETY of a new drug molecule in human, thereby bye-passing phase-1 clinical trial?
Many drugs fail in Phase II clinical trials due to flaws in the original scientific hypothesis. Amgen Pharmaceuticals were only able to reproduce the findings in 6/53 landmark papers and Bayer Healthcare found inconsistencies between published findings and the company's own results in about two thirds of projects. The use of hiPSCs should help to reduce this failure rate, reduce the number of animals used in pre-clinical studies and reduce development costs. Ultimately, it may also reduce animal use in safety testing. But these new methods need to be rigorously tested and validated to ensure that they are robust and fit-for-purpose before abandoning all animal experimental studies.Following
Joe Graymer added an answer:Who is carrying out preclinical research with Doxorubicin derivatives?
In our research, we synthesized in a straightforward way a very potent fluorine derivative of Doxorubicin exhibiting nM IC50s in the two cell lines that we preliminarily tested. It could be especially interesting as a second-line treatment option (active in Dox-resistant strains) with possibly reduced cardiotoxicity.
Unfortunately we lack the knowledge and/or research focus to carry out further studies.
Does anybody know of a research group which is carrying out preclinical research on anthracycline derivatives?
Answers are greatly appreciated
I just became aware of an article about a new Anthracycline anticancer antibiotic from an Streptomyces, by Wei Li et al, in The Journal of Antibiotics, Mar 2015, and also about PMID 25319239 by Braña et al, 2015, perhaps by looking at these papers you find names of those working in the fieldFollowing
D'Souza Joseph added an answer:Any suggestions on a doubt in small intestinal perfusion study?
Kindly some one help me to calculate the Peff value from the small intestinal perfusion study. We are collecting samples for the regular interval of time and analyzing the concentration (Cout). So we will get "n" number of values.
With the equation we can calculate the Peff value. Peff=-Q*ln(Cout/Cin)/(2*pi*rL).
Here which Cout value I should take. Is it the average or summation of all the Cout values. Please help.
Thanks in advance
Thank you so much for giving the valuable reply. Actually I'm going to find the effective permeability of a emulsion. In most of the research articles, Peff was calculated for the drug. So they perfused the drug in the intestine and checked the difference in concentration.
My query is why the researchers are not using any digestive enzyme? Why the gastriointestinal digestion was not accounted during the perfusion study? Some researchers used Pancreatin in the buffer. Is that enough for digestion. As I'm using the emulsion, with protein as a surfactant, I need to digest the material before entering the intestine. Can I follow the Pancreatin digestion..
Kindly suggest a method..Following
Bhukya Bhima added an answer:Does any one know about mice studies for Mycobacterium Tuberculosis?
We have few isolates of Mycobacterium Tuberculosis and few small molecules. Primarily we have screened small molecules on Mycobacterium isolates and now we want to see the effect of small molecules on invivo models of mice by infecting them with Mycobacterium Tuberculosis. Please suggest us by providing some references.
Thank you very much Dr. Lawrence and AmarFollowing
Mark Connor added an answer:Does the plate surface area affect the IC50 obtained for a compound?
I am currently working with a small molecule inhibitor and determined the IC50 for it in a 6-well plate format. However, I was told that the IC50 is not directly applicable if using a different plate format (i.e. 24-well plate) for subsequent experiments. Is this true? For a typical experiment using a 6-well plate, I normally seed 1.0X10^5 cells/mL and 1.0x10^4 cell/mL for a 24-well plate. Any suggestions and feedback will be greatly appreciated!
Assuming your drugs don't bind to the plates (eg cannabinoids)....Following
Vladimir A. Kulchitsky added an answer:Is mammary gland tumor induction in Sprague-dawley rats with rat mammary tumor cell line LA7 reliable for antitumor activity assessment?
Induction of a mammary gland tumor in female Sprague-dawley rats by inoculation of rat mammary gland tumor cell line, LA7. I would like to get some advice : Is this model reliable for assessment of anti-tumor action? I got some references for this model.
1. Evaluation of cytotoxic and chemotherapeutic properties of boldine in breast cancer using in vitro and in vivo models (Drug Design, Development and Therapy 2014:8 719–733)
2. Induction of mammary gland tumor in female Sprague-Dawley rats with LA7 cells (African Journal of Biotechnology Vol. 9(28), pp. 4491-4498, 12 July, 2010)
I'm looking to find a reliable tumor model with cell-line as cost and time are limiting factors. Thank you for your attention.
Currently, during preclinical testing in vitro are two critical positions. Firstly, it is desirable to use human cell line culture. And secondly, it is necessary to apply the model of 3D cell culture. It may be linear or culture cells of the primary cell culture. Both of these requests are directed to the maximum approximation test conditions to natural conditions characteristic of a person (including a three-dimensional principle of cell populations at the level of the whole organism).
Please, try to open the link below.
James Sy-Keen Woon added an answer:How can I define if one enzyme is a novel enzyme?
Let say if I identified a potential gene encoded for an enzyme from the genomic data, that it has never been expressed nor characterized before, does it qualify to be known as a novel enzyme if I successfully cloned and expressed it? If it is, will this status remains if this enzyme possesses other homologous sequences that encoded enzymes of similar function (and normally this would be the case as enzymes contain conserved domain).
Thank you Dr. Bharath Srinivasan, your answer has perfectly explaining my doubts!Following
Ildikó Pál added an answer:Can multidrug resistance-associated proteins cause uneven calcium dye loading in acute hippocampal slices?
I am new to the field of calcium imaging. I used OGB-1 AM dye at 2 uM concentration for 1 hour at 35 C in adult rat hippocampal slices. Only neurons in the stratum radiatum were loaded and the pyramidal cells were not. Bootman et al 2013 claim in their article that if they stain cell cultures above room temperature they inhibit the multidrug resistance-associated proteins (MRP) for better dye loading. Can MRP activity cause also uneven dye loading in the slices? I would be grateful for any suggestions.
Thank you for your answer!Following
Kaddouch Yael added an answer:Is there any mention of "Time to relapse" with in vivo preclinical experimentation?
I'm searching for informations on the "time to relapse". I found a little bit of litterature on this topic but it's always on the context of clinical trials. I would like to know if there is some papers on this applyed on the preclinical trials.
Thanks you !
No, that means I'm gonna do some research on time to relapse ALSO on clinical studies because at the begining I was interested in preclinical studies.Following
Carlo Condello added an answer:Who can name a lab or vendor which has experience with multiplexed immunofluorescence in preclinical animal models, especially with brain tissues?
GE offers their MultiOmyx methodology for multiplex IHC and imaging
Shazlan Noor Suhaimi added an answer:What is the most appropriate volume to be injected via IP in a mouse?I want to inject mice via IP route using 26-G needle for 2 weeks. Drug concentration to be used is e.g. 5mg/kg of body weight (0.025mg/1ml drug concentration). I intend to use 0.5 ml (for a mouse wieighing 25g). For example: A 24g mouse requires 0.48 ml ([24/25g] x [0.5ml]) and that IP injection requires at least 3.5 to 4 seconds. But, I'm worried the volume to be injected that is probably can cause stress or physical discomfort. Can I reduce the volume from 0.5ml to 0.4ml? Meaning (24/25g) x (0.4ml) = 0.38 ml. Is that ok?
Thanks Robert. I heard about this Alzet pumps before. Do you have experience using that for mouse study?Following
Adejuwon Adeneye added an answer:Which triton (x 100 or wr1339) might be used to induce hyperlipidemia?
In order to screen the hypolipidemic drugs, Triton induced hyperlipidemic animal model is being used. In most of the papers, Triton WR 1339 (tyloxapal) was used to induce hyperlipidemia. However, in some paper Triton X 100 was used. Which Triton is best or ideal to induce hyperlipidemia in rat model.
Thanks in advance for replies.
Triton WR-1339 reliably induces hyperlipidemia in rodents treated with it without fatalities unlike triton X-100 which kills animals as a result of its attendant hemolysis for which it is notoriously reputable.Following
Kulvinder Singh Saini added an answer:Where can we source New Chemical Entities (NCEs) against breast cancer, which failed in phase-1 or 2 clinical trials?
Does anyone know, if global pharmaceutical/biotech companies/NIH, USA/USFDA, NGOs, etc. will be willing to give/sell us small amounts (mg quantity) of their small molecule compounds (NCEs), where possible toxicity issues hampered their clinical development as cancer therapeutics? We are interested in further exploring Toxicogenomics and mechanism-of-actions of these NCEs in a mouse model of breast cancer? Even NCEs which failed in clinical development against other cancers will be of great research interest to us.
Please check this URL from AstraZenecaFollowing
R. Selvam added an answer:Does anyone know where I can obtain lyophilized herceptin for preclinical R&D?
I am looking for lyophilized herceptin. Would anyone (not affiliated with Genentech) be willing to provide this material? Or do they know of another company that will sell it (or the generic version) to me?
Dear Thad Wadas,
Send your quires to us, www.gmrfoundation.com , we can able to provide lyophilized herceptin, if you need any other specification also inform us, For only R&D use, not for any human use.,
Good Luck & Regards
Bruce Koch added an answer:What are the best kinase inhibition profiling assays and microsome stability test systems for anti-tumor property screening?
We test small molecule compounds for anti-tumor properties. We would like to test the kinase inhibition activity of our lead candidate. We don't know its biological target yet. No prior experience in these types of assays.
Which is your favorite company/screening technology (in the United States) to test the kinase inhibition activity of your compound? Is a functional assay necessary or is a binding assay sufficient in this case?
Also, which assay kit/company do you use for testing the microsome stability of your compound?
Our experience is that assaying a subset of the kinome is not very informative. Inhibitors are often selective between closely related kinases, but then hit somewhere else in the kinome. You might check out DiscoverX KinomeScan (formerly Ambit).Following
Neelima Jitendra Deuskar added an answer:Have you observed any differences in cell viability after treatment with chemotherapeutic agents with cells seeded on a flask vs. on a plate?
I observed this phenomena with different cell lines and anticancer agents. To be specific for example, when A549 cells were treated with same concentration of taxol, less cells die if the cells were seeded in a 25cm2 or 75 cm2 flask compared to the cells seeded into 96 well plates (microscopic observation). Ratio of the seeded cell number to the surface area was the same, but the result did not change. Does anyone have an idea what might cause this?
It is the quality of plasticware used that makes difference at times. Occasionally a particular lot even from a reputed brand does not give consistent results. It is necessary to rule out the margin/periphery/border effect seen in 96-well plates.Following
Shaban Ahmed Ali Abdel-Raheem added an answer:Does anyone know of a cell line that expresses R-D1 y R-D2L?Or maybe a well established protocol to induced SH-SY5Y to express them?Following
Majid Avijgan added an answer:Where can I test and confirm Anti-tuberculosis and Anti-HIV activity for Plant extract samples?
Hi friends, I wish to do Antituberculosis and Anti HIV activity for Plant samples. Do you people know about any one doing out sourcing these experiments. I am ready to pay for this work. Or I will give authorship This work is my own interest on natural drug discovery.
I have several studies on the echinophora platyloba as an anti fungal herb. I have experience of what you are looking for. It is easy and simple, just invite from one of the pharmaceutic for co-operation. I have one co-worker in my paper as Dr Mohadese Mahboubi. Her email is as firstname.lastname@example.orgFollowing
Anju Wakade added an answer:How to extrapolate result from in vitro (ug/mL) to in vivo?I have obtained result from in vitro which 10 ug/mL. How to predict what value of doses we need to use in the mouse (mg/kg). Is there any specific calculation to extrapolate the data to mg/kg? or we need to test the doses beforehand?
Your kind advice is greatly appreciated.hii
I have a similar situation wherein the effective conc in vitro was 0.04% v/v and 0.08%v/v. i want to try it in mice (weighing 30-35mg) thru oral feeding. what conc should i use. My LD50 studies using oral route is 10ml/kg ie greater than 9257.50 mg/kg.Following
Pooja Shukla added an answer:How do you induce anemia in a guinea pig?I am evaluating hematological parameters in medicinal plants including anemia kindly tell me the methodology to induce anemia in guinea pigs, the reason to choose guinea pigs is the lower number of animals used and lower death rates.Following
Lawrence Broxmeyer, MD added an answer:Can anyone suggest a drug that can possibly be effective on an Alzheimer's rat model?I am having trouble finding a drug that crosses BBB and could possibly help to cure AD induced cognitive impairment in a rat model.Run your study using standard antitubercular drugs to cure AD induced cognitive impairment in your rat model.Following
Shaban Ahmed Ali Abdel-Raheem added an answer:Can anybody help me to find an adapted center with which to perform preclinical studies of biosimilar drugs?It can be all around the world but an important matter is the cost. Please let me know about your experiences.Following