Histopathology is the most useful tool for diagnosis of a number of diseases, especially cancer. To be effective, histopathology requires that tissues be fixed prior to processing. Formalin is currently the most common histologic fixative, offering many advantages: it is cheap, readily available, and pathologists are routinely trained to examine tissues fixed in formalin. However, formalin fixa...

Animals communicating via scent often deposit composite signals that incorporate odorants from multiple sources; however, the function of mixing chemical signals remains understudied. We tested both a 'multiple-messages' and a 'fixative' hypothesis of composite olfactory signalling, which, respectively, posit that mixing scents functions to increase information content or prolong signal longevi...

The value of osmium tetroxide (OsO4) as a superior fixative for the structure of cells and tissues has been recognized for some time (1). However, staining of OsO4-fixed tissues with the usual histological stains such as hematoxylin and eosin (H and E) or with the Feulgen reaction has met with great difficulty in the past. Baker (2), who discusses OsO4 fixation in great detail, states tha t the...

Aldehyde fixation continues to be useful to prepare synapses for freeze-fracture, but it may increase the rate of transmitter release. The effects of different aldehyde fixatives on spontaneous quantal release (m.e.p.p.s), and on the corresponding synaptic vesicle exocytosis at frog nerve-muscle synapses were investigated with the hope of finding a way to minimize side effects of fixation. Incr...

Fixation was initiated by adding an equal volume of fixative solution, previously warmed to 37°C, to the cells after treatment with zinc oxide nanoparticles for 24 hours. The fixative solution contained 5% glutaraldehyde (Electron Microscopy Sciences. Euromedex, Strasbourg, France) in a 0.1 M sodium cacodylate buffer (both Merck, Darmstadt, Germany) (305 mOsm. pH 7.3). After 10 min the mixture ...

The binding of labeled free amino acids to liver and to purified protein by commonly used fixatives was investigated. Glutaraldehyde caused 25% of free leucine to be bound to serum albumin in solution, whereas formaldehyde bound only 0.5%. Liver slices were incubated for 2 min in the presence of labeled leucine and of puromycin, which permits absorption of leucine into the cell but inhibits inc...

Periodate-lysine-paraformaldehyde (PLP) has been proposed as a fixative for glycoprotein antigens which should stabilize periodate oxidized polysaccharide chains through lysine mediated crosslinks, either directly or by the intermediation of formaldehyde. In spite of premises and attempts reported in the literature, this fixative has never become popular for the study of membrane antigens of im...

Many marine biology studies depend on field work on ships or remote sampling locations where sophisticated sample preservation techniques (e.g., high-pressure freezing) are often limited or unavailable. Our aim was to optimize the ultrastructural preservation of marine invertebrates, especially when working in the field. To achieve chemically-fixed material of the highest quality, we compared t...