you want to carry a bottle of toxic liquid on your car? or you will take a box of powder that can dissolve into useful solution easily?
You have to add methanol in 10% formalin & 4% formaldehyde, rather 4% paraformaldhyde....PFA is methanol free..it's very important. 2008-12-06 tf 发件人： Reuel Cornelia 发送时间： 2008-12-06 00:09:36 收件人： Tony Henwood; [EMAIL PROTECTED]; histonet; [EMAIL PROTECTED]; Jan Shivers 抄送： 主题： RE: RE: [Histonet] IHC on paraformaldehyde-fixed I have been curious about this discussion. we used 4% paraformaldehyde for smaller biopsies only because it has a faster penetration to tissue than 10% formalin. In all my IHC that I have done. I observe that doing an IHC with 4% paraformaldehyde does not necessarily need antigen retrieval in comparison to 10% formalin either it will be human or animal tissue but this depends on how long was it fix, our 4% paraformaldehyde we fix smaller biopsies like nerve,muscle, skin for 6 to 12 hrs. and for formalin it is 12 to 48 hours or more. Maybe you can comment on the effect on this to tissue if you say you will use 4% paraformaldehyde for storage and transportation. Reuel Cornelia, BS MT, AMT Cellular Pathology Texas Scottish Rite Hospital for Children 2222 Welborn Street Dallas, TX 75219 Tel: 214-559-7766 fax: 214-559-7768 >>> "Tony Henwood" <[EMAIL PROTECTED]> 12/04/08 9:29 PM >>> tf wrote: "I DO believe that one reason some people use 4% PFA rather 10% formalin is that PFA is a bit more stable, both for storage and transportation~~~." I have not heard this before. Do you have a reference for this? Regards Tony Henwood JP, MSc, BAppSc, GradDipSysAnalys, CT(ASC) Laboratory Manager & Senior Scientist Tel: 612 9845 3306 Fax: 612 9845 3318 the children's hospital at westmead Cnr Hawkesbury Road and Hainsworth Street, Westmead Locked Bag 4001, Westmead NSW 2145, AUSTRALIA -----Original Message----- From: tf [mailto:[EMAIL PROTECTED] Sent: Friday, 5 December 2008 2:11 PM To: Tony Henwood; [EMAIL PROTECTED]; Jan Shivers; histonet Subject: Re: RE: [Histonet] IHC on paraformaldehyde-fixed the basic principles are the same for most cross-linking fixatives and induce similar bonds the difference you observed between may due to any other variability, or the co-fixative you used. I DO believe that one reason some people use 4% PFA rather 10% formalin is that PFA is a bit more stable, both for storage and transportation~~~. 2008-12-05 ________________________________ tf ________________________________ 发件人： Tony Henwood 发送间： 2008-12-05 06:00:03 收件人： [EMAIL PROTECTED]; Jan Shivers; histonet 抄送： 主： RE: [Histonet] IHC on paraformaldehyde-fixed Interesting point. Since 10% buffered formalin (made from the concentrated 38% formaldehyde) contain about 1% methanol, has it been shown that this has a deleterious effect on ANY antigens or are we expecting this worse case senario as being the norm? I am not aware of any antigens (or antigen-antibody combination) that has been badly effected by 10% formalin that is NOT effected by 10% formaldehyde. Are you aware of any?? Regards Tony Henwood JP, MSc, BAppSc, GradDipSysAnalys, CT(ASC) Laboratory Manager & Senior Scientist Tel: 612 9845 3306 Fax: 612 9845 3318 the children's hospital at westmead Cnr Hawkesbury Road and Hainsworth Street, Westmead Locked Bag 4001, Westmead NSW 2145, AUSTRALIA -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Friday, 5 December 2008 1:31 AM To: Tony Henwood; Jan Shivers; histonet Subject: Re: [Histonet] IHC on paraformaldehyde-fixed So true. However, be aware that 10% neutral buffered formalin we use has methanol in it which may affect certain antigens so there may be some difference in staining (hence why for mouse work we now only use 4% PFA in pure PBS). It is good to be aware of the other ingredients in your fixative solutions, whether commercially prepared or a homemaede recipe, as it isn't only the formaldehyde fixative which can make a difference. -----Original Message----- From: Tony Henwood <[EMAIL PROTECTED]> Date: Thu, 04 Dec 2008 09:35:09 To: Jan Shivers<[EMAIL PROTECTED]>; histonet<histonet@lists.utsouthwestern.edu> Subject: RE: [Histonet] IHC on paraformaldehyde-fixed Gee I hate the term paraformaldehyde (as many of you probably know) This is an example of how confusion of terms can cause unnecessary work. Is "4% paraformaldehyde" different from 4 % formaldehyde? No Should any procedure done to tissues fixed in "4% paraformaldehyde" give results different to those fixed in 4% formaldehyde or 10% formalin? No since they are the same thing. As Manoonkitiwongsa and Schultz (Histochem J 34: 365-367, 2002) state when paraformaldehyde actually becomes a fixative, it is no longer paraformaldehyde by chemistry or fixation capacity. Rather, it is formaldehyde in water without methanol or any other stabiliser. Without heat and an alkaline environment, paraformaldehyde in water is simply a paraformaldehyde suspension with little fixation capacity. If the fixative is prepared from paraformaldehyde then it should be termed 4% formaldehyde freshly prepared from paraformaldehyde. If a concentrated formalin solution (40% formaldehyde) is used, then it should be termed 10% formalin. If you do a search on Histonet for paraformaldehye, you will find that this topic has been extensively discussed. Regards Tony Henwood JP, MSc, BAppSc, GradDipSysAnalys, CT(ASC) Laboratory Manager & Senior Scientist Tel: 612 9845 3306 Fax: 612 9845 3318 the children's hospital at westmead Cnr Hawkesbury Road and Hainsworth Street, Westmead Locked Bag 4001, Westmead NSW 2145, AUSTRALIA -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jan Shivers Sent: Thursday, 4 December 2008 8:34 AM To: histonet Subject: [Histonet] IHC on paraformaldehyde-fixed Has anyone ever done IHC on parafomaldehyde-fixed tissues, and if so, how well did it work? Will the same antigen-retrieval methods used with formalin-fixed tissue be applicable? I'm asking for an investigator, who already has his tissues fixed in paraformaldehyde. Jan Shivers Senior Scientist Pathology Teaching Program Histology/IHC/EM Section Head University of Minnesota Veterinary Diagnostic Laboratory 1333 Gortner Ave. St. Paul, MN 55108 612-624-7297 [EMAIL PROTECTED] Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet ********************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, please delete it and notify the sender. Views expressed in this message and any attachments are those of the individual sender, and are not necessarily the views of The Children's Hospital at Westmead This note also confirms that this email message has been virus scanned and although no computer viruses were detected, The Childrens Hospital at Westmead accepts no liability for any consequential damage resulting from email containing computer viruses. ********************************************************************** _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet ********************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, please delete it and notify the sender. Views expressed in this message and any attachments are those of the individual sender, and are not necessarily the views of The Children's Hospital at Westmead This note also confirms that this email message has been virus scanned and although no computer viruses were detected, The Childrens Hospital at Westmead accepts no liability for any consequential damage resulting from email containing computer viruses. ********************************************************************** _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu ********************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, please delete it and notify the sender. Views expressed in this message and any attachments are those of the individual sender, and are not necessarily the views of The Children's Hospital at Westmead This note also confirms that this email message has been virus scanned and although no computer viruses were detected, The Childrens Hospital at Westmead accepts no liability for any consequential damage resulting from email containing computer viruses. ********************************************************************** _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet ******************************************************************************************************************* Texas Scottish Rite Hospital for Children is one of the nation's leading pediatric centers for the treatment of orthopedic conditions, certain related neurological disorders and learning disorders, such as dyslexia. This email transmission and/or its attachments may contain confidential health information, intended only for the use of the individual or entity named above. The authorized recipient of this information is prohibited from disclosing it to any other party unless required to do so by law and is required to delete/destroy the information after its stated need has been fulfilled. If you are not the intended recipient, any disclosure, copying, distribution or action taken in reliance on the contents of this email transmission is prohibited. If you have received this information in error, please notify the sender immediately and delete this information. We appreciate your efforts to protect the children's confidential information. *******************************************************************************************************************
_______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
