- Denise Priolli added an answer:10Does anybody has any experience with 786-O(RCC) induced xenograft nude mice models?Any suggestions about the optimum cell no. for inoculation as I had inoculated 786-O (5 *10 ^ 6 cells/animal, Subcutaneously in flank region) in CD1 nude mice. After one week I observed tumorous swellings up to 100 mm3 at the site of inoculation and then it disappeared after the 2nd week. What could be the reason?
The routine for renal adenocarcinoma/786 is the fast growth followed by disappearance of tumor due to NK response in nude mice. In a pilot that I conducted with three animals I had successonly in one animal, but after re-inoculation of 4X10E6 cells. The literature reports that the xenograft works in BALB/c nu beige or SCID but I have no experience with these strains.Following
- Sujit Kashyap added an answer:6Can or should, a monoclonal antibody for western blot, IHC etc application be used for an animal study?
I wish to study the effect of the monoclonal antibody against a certain protein. Can i purchase this monoclonal antibody for animal study from the widely known companies that are generally used for western blot, IHC etc? If not then why?
Dear Bret Lum, i was talking about the use of rat monoclonal antibody in the rat model of disease. I guess this will not develop antidrug antibody if so then please explain how.Following
- Mohammad Sadegh Amiri added an answer:19Can a plant with antioxidant effect also increase lipid peroxidation?
I am investigating the hepatoprotective effect of some medicinal plant on chronic carbon tetrachloride induced liver injury. I observed that although some of the medicinal plants increased the antioxidant enzyme (SOD, CAT and GSH) level in rats co-exposed to CCl4 and the extracts while they also increased lipid peroxidation and markers of hepatic injury such as ALT and AST.Has anyone experienced something similar? If yes, what are the likely reasons why this happened?
Dear Ifeoluwa T Oyeyemi
I am attaching literature on the anticancer properties. I hope they will be useful to you.
I recommend the fruit of Rhus coriaria L. (Anacardiaceae) for your research.
- Alessandra Tiziana Peana added an answer:6Do you know how to administer bromocriptine s.c. or i.p. without using alcohol?
I have to administer bromocriptine (BC) to mice to inhibit prolactin release to analyse the role of this hormone in behaviour. BC has a very low solubility in water. People usually do a stock (saturated) solution of BC in pure ethanol and then disolve it in PBS or water and inject it s.c. Since the final concentration of alcohol might be nearly 10%, BC injections are probably very painful, and this may invalidate the results of the ensuing behavioural analysis.
I've thought of using DMSO, in which it is much more soluble. Has anybody experience of drug administration in solutions containing relatively high concentrations of DMSO (about 1%)? Could I use i.p. injections, in that case?
- Hafiz Iftikhar Hussain asked a question:OpenWhich breed of cat is mostly used for Pharmaco-kinetic studies?
if more than one breeds used please inform.
- Marcus Vinicius P.S. Nascimento added an answer:7Can I use the OECD guideline #423 to test toxicity of a synthetic compound via intraperitoneal route in mice?
I know this is a guideline for acute oral toxicity, but I can't find any current guideline to test synthetic compounds via the intraperitoneal route in vivo (mice). OECD 423 seems to be the protocol that uses less animals. Does anyone know if I can use it as described in the protocol changing only the administration route (Oral to Intraperitoneal)?
guideline 423: http://ntp.niehs.nih.gov/iccvam/suppdocs/feddocs/oecd/oecd_gl423.pdf
So OECD 401 can be used with intraperitoneal route but 423 can't? I thought OECD 423 would be better accepted because it uses less animals than 401. Don't you think that this might influence later publications (the use of a unnecessary number of animals)?Following
- Christopher Jobdevairakkam added an answer:3Do you think that infusion pumps in preclinical studies can add variability to your results?
There is a recent study by John Osborn that demonstrate that if you use an alzet pump for delivering angiotensin you get a lot variability in your blood pressure readouts as compared to new technology pump such I-precio or tethered.
What is your opinion on that?
Usually all the infusion pumps are periodically calibrated and the variation can be less than 2%. Having said that, for a given application if the infusion time is less than, say 3 hrs, the variation can be +/- 3.6 min. that is not a significant variation. However if the infusion time is more than 12 hrs, hope you can imagine the large variation that could lead a significant difference in dosage administration.Following
- Stephen Haber added an answer:2Is NMS-P626 the same as RXDX-101 and NMS-e628?
The drug name is entrectinib. I am looking for pre-clinical studies and I can not figure out if they are the same drug.
They are the same.
- Bharath Srinivasan added an answer:9Which terminology is suitable for this situation below?- 'drug target' is suitable?
We have found a gene of which expression are known to play a crucial role in human disease. in our experiments, the levels of mRNA and proteins of the gene are reduced in a drug treatment. However, we did not have know whether the drug interact with the protein directly. Seemingly, the drug might be involved only in the gene expressional regulation with no direct interaction with the protein product.
In this case, can we term the gene as the drug target? or etc..?
(ex. identification of 'gene name' as a drug target of 'drug name')
What is the most suitable term for the description in this situation?
Reference information is also very appreciated.
Dear Dong-Myung Kim,
Your question is interesting. However, caution may need to be exercised in calling the gene a "drug target" of the small molecule. It is mandatory to demonstrate that other genes do not show any effect vis-a-vis their expression and protein levels for you to specifically claim that the small-molecule targets the gene of interest. Lot of small molecules have been shown to have a global effect on the downregulation or upregulation of several different genes by targeting RNA polymereases, repressors and activators and transcription factors. I hope the answer helps.Following
- Sandeep Rajput added an answer:1What are the protocols needed to manufacture injectable VEGF-C without a hydrogel delivery vehicle?
I'm looking at injecting VEGF-C into a rat model, specifically into the medial right thigh tissue. I'm going to do this after removing a lymph node.
From the literature i have seen so far, most researcher's have combined VEGF-C with a hydrogel (HAMC [Baker et al., 2010] or Gelatin [Hwang et al., 2011]) before injecting into the lymph node region.
Can VEGF-C brought stragiht from a manufacture (eg R &D - Recombinant Human VEGF‑C) be injetcted into rat tissue without further modification? if modification is needed, can VEGF-C be dissolved in PBS prior to injection?
NB: Dont wont want to use Adenovirus VEGF-C.
I'm asking this question because time is short to prepeare a injectable delivery vehicle for VEGF-C. However i'am open to suggestions which are simple and can be manufactured in a hour.
The volume of VEGF-C i want to deliver are similar to the values mentioned by [Baker et al., 2010] and [Hwang et al., 2011
The only reason they used Hydrogel is to increase the solubility or to localized the VEGFC into tissue only. If VEGFC is soluble in PBS , u can inject it directly.Following
- Muzammil Najmi added an answer:3How can I make a good use of leftover human specimens?
Recently, I may have a chance to receive a large batch of leftover specimens. Besides using these leftover specimens for research, I am also thinking about the possibility of turning these specimens into some products which can generate funding for future academic research development of my lab. Did anyone have experience in similar scenario or know any institute which is doing something similar? Thank you.
The human specimens should not be used for purposes other than the ones for which permission/consent was obtained from the subjects at the time of collection. Particularly, use for commercial purposes (raising funds, as it has been mentioned) will be attended with huge ethical concerns. These may however, be used to further extend the research for betterment of humanity.Following
- Adelaeda Barrera added an answer:7Has 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:15How 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:2How 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:3Is 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:3Is 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:11Any 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:2How 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:2Does 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:4Do 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:8Who 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:5Any 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:3Does 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:4Does 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:1Is 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:5How 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:2Can 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:8Is 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:2Who 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:34What 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