BACKGROUND Identifying the influence formalin fixation has on RNA integrity and recovery from clinical tissue specimens is integral to determining the utility of using archival tissue blocks in future molecular studies. For clinical material, the current gold standard is unfixed tissue that has been snap frozen. Fixed and frozen tissue however, both require laser capture microdissection to sele...

The effect of fixation technique and post mortem-to-fixation interval in immersion-fixed tissue from the central nervous system on immunocytochemical staining for the presence of an immunoglobulin was determined in mice. Immersion-fixed tissue was found to be inferior to perfusion-fixed tissue for immunocytochemical staining of this serum protein. Unlike what has been observed for other antigen...

Formaldehyde fixation and paraffin-embedding remains the most widely used technique for processing cancer tissue specimens for pathologic examination, the study of tissue morphology, and archival preservation. However, formaldehyde penetration and fixation is a slow process, requiring a minimum of 15 hr for routine processing of pathology samples. Routinely fixed samples often have a well-fixed...

Comparative studies of the structural organization of the brain are fundamental to our understanding of human brain function. However, whereas brains of experimental animals are fixed by perfusion of a fixative through the vasculature, human or ape brains are fixed by immersion after varying postmortem intervals. Although differential treatments might affect the fundamental characteristics of t...

introduction: the effects of different doses of oestrogen on the endometrium of women with premature ovarian failure have been examined in this study. materials and methods: four groups of women of reproductive age were studied; 1 normal fertile controls 2. patients given a standard, variable hormone replacement therapy (hrt) 3. a group given a fixed daily dose of 1 mg of oestrogen and 4. a gro...

PURPOSE A quantitative study was performed to compare the effect of two commonly used fixation pressures, 0 mm Hg (immersion) and 10 mm Hg (perfusion), on the porosity of the juxtacanalicular tissue and the size of Schlemm's canal. METHODS Twelve pairs of human eyes were studied by fixing one eye with perfusion fixation and the fellow eye with immersion fixation. Morphometric analysis of the ...

A new autometallographic (AMG) technique for staining myelin in formaldehyde- or paraformaldehyde- (PFA) fixed tissue is presented. The tissue sections were exposed to AMG development without prior treatment with silver salts. The method was examined on PFA-fixed tissue from mouse, rat, pig, and formaldehyde-fixed human autopsy material. Samples from brain, spinal cord, cranial, and spinal nerv...

Diffusion tensor microimaging at 16.4 T with 40 μm isotropic voxels was used to investigate anisotropic water diffusion in prostate tissue at spatial resolution approaching the cellular scale. Nine normal glandular tissue samples were collected from the peripheral zone of six formalin fixed radical prostatectomy specimens. Fibromuscular stromal tissue exhibited microscopic diffusion anisotropy ...

PURPOSE To investigate the microscopic diffusion properties of formalin-fixed breast tissue. METHODS Diffusion microimaging was performed at 16.4T with 40-μm isotropic voxels on two normal and two cancer tissue samples from four patients. Results were correlated with histology of the samples. RESULTS Diffusion-weighted images and mean diffusivity maps demonstrated distinct diffusivity diffe...