The molecular fixative for optimal DNA and RNA
Hospital tested for routine H&E, IHC, HC and Molecular analysis
FineFIX has been extensively tested in a hospital laboratory environment to ensure its suitability staining for diagnostic purposes.
The morphology of FineFIX fixed tissues processed either conventionally or by microwaves is of a such high quality that it poses no difficulty for diagnosis.
Shrinkage and vacuolization are reduced to a fraction of what is experienced with traditional ethanol fixation. Pyknotic nuclei are also absent.
H&E Staining
Tissues fixed in FineFIX show improved H&E staining intensity and cytological details.
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Bone marrow FineFIX H&E x400
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Ovarian Carcinoma. FineFIX H&E x 100
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Adipous tumor. FineFIX H&E x 100
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Gastric epithelium FineFIX H&E x400
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Kidney, FineFIX H&E x400
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Prostate nodular hyperplasia FineFIX H&E x100
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Skin melanocytic nevus FineFIX H&E x100
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Liver. FineFIX H&E x 400
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Immunohistochemistry
Improved Immunohistochemical staining by reducing the need for aggressive epitope retrieval.
Meningioma staining for Vimentin x200
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Ependymoma staining for Cytokeratin CAM5.2 x200
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Breast. FineFIX ER (6F11)
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Breast carcinoma staining for Mib-1 x400
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Breast carcinoma for P-53 x200
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Breast. FineFIX Fish for Her2-neu
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Histochemistry
When using FineFIX, special stains procedures can be carried out without any change to existing protocols.
Kidney PAS stain FineFIX x100
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Bowel, Alcian Blue. FineFIXx 100
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Kidney Reticulin stain FineFIX x200
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Kidney, Jones silver stain FineFIX x400
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Cytology
FineFIX is well suited for use as a cytological fixative compared to Ethanol.
Meningioma,
FineFix x200
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Meningioma,
Ethanol x200
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Molecular Biology
 Although formalin-fixed and archived tissues are a huge source of DNA for molecular biological studies in cancer research, screening for genetically based diseases and developmental biology studies, attempts to extract DNA from formalin-fixed tissues for molecular biological studies have been variably successful . Formalin fixation at room temperature results in poor preservation of high-molecular weight DNA, the size of the extracted DNA being directly related to the fixation temperature.
Even short-term treatment of sections with formalin have been shown to significantly reduce DNA solubility , with up to 30% of nucleic acids being lost during the fixation process .
With the expansion of PCR and other techniques for nucleic acid analysis for clinical diagnosis, an understanding of the deleterious effects of formalin as the primary method of choice, followed by recovery of preserved DNA and RNA is becoming increasingly important, as the need for molecular pathology to arrive at a conclusive diagnosis will increase in the future.
Multiple studies have indicated that the use of non cross-linking alcoholic reagents yielded superior results as nucleic acid fixatives, rather than aldehydes.
A Novel Fixative Improves Opportunities of Nucleic Acids
and Proteomic Analysis in Human Archive’s Tissues
Giorgio Stanta, MD, Stefano Pozzi Mucelli, MS, Francesca Petrera, MS, Serena Bonin, PhD, and Gianni Bussolati, MD
DIAGN MOL PATHOL. 2006 june 15(2): 115-23.
| DNA amplification by PCR |
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RNA amplification by RT-PCR |
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Ten samples five from formalin-fixed and five from FineFIX-fixed tissues were subjected for DNA extraction.
250 ng of DNA of each sample has been amplified using a primer of 291 bp (data not shown), 339 bp (A), 1000 bp (B), 1939 bp (data not shown) , 2396 bp (C) region of human transthyretin gene.
Each gel (A, B and C) shows:
Lane 1, molecular size marker; Lane 2-6, DNA obtained from formalin-fixed tissues; Lane 7-11, DNA obtained from FineFIX-fixed tissues; Lane 12, negative control; Lane 13, DNA from HepG2 cells, positive control. |
Ten samples five from formalin-fixed and five from FineFIX-fixed tissues were subjected for RNA extraction.
500 ng of RNA extracted from all samples were subjected to DNase and RT-PCR amplification using a set of 170 bp (A), 200 bp (B), 600 bp (C) region of beta-actin gene.
Each gel (A, B and C) shows:
Lane 1, molecular size marker; Lane 2-6, RNA obtained from formalin-fixed tissues; Lane 7-11, RNA obtained from FineFIX-fixed tissues; Lane 12, negative control; Lane 13, mRNA from HepG2 cells, positive control. |
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DNA Amplification Comparison Between Formalin and FineFIX, Number of Positive Results After PCR Amplification
Lenght (Bases) |
Formalin Fixed |
FineFIX |
291 |
5/5 |
5/5 |
339 |
5/5 |
5/5 |
1000 |
0/5 |
5/5 |
1900 |
0/5 |
5/5 |
2400 |
0/5 |
5/5 |
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RNA Amplification Comparison Between Formalin
and FineFIX, Number of Positive Results After RT-PCR Amplification
Lenght (Bases) |
Formalin
Fixed |
FineFIX |
77 |
5/5 |
5/5 |
170 |
5/5 |
5/5 |
200 |
0/5 |
5/5 |
450 |
0/5 |
5/5 |
600 |
0/5 |
3/5 |
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Protein analysis - Western Blot
Seventy mg of whole protein extract both from formalin-fixed and from FineFIX - fixed tissues was loaded and run onto SDS - PAGE electrophoresis before blotting.
No proteins were detected from the formalin-fixed tissues either for alfa-tubulin (a-tubulin) and for tissue transglutamminase (tTG), although the extract from FineFIX-fixed tissues gave similar protein quality of those from fresh tissues.
Prefusion
Perfusion fixation in animal research laboratories has been carried out with optimum results.
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