Coating processes – Medical or dental purpose product; parts; subcombinations;... – Analysis – diagnosis – measuring – or testing product
Patent
1998-11-23
2000-03-28
Dudash, Diana
Coating processes
Medical or dental purpose product; parts; subcombinations;...
Analysis, diagnosis, measuring, or testing product
427 4, 427296, A01N 100, B05D 134
Patent
active
060428740
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to the processing of organic tissues to prepare them for further investigation. More specifically the present invention relates to a process for processing organic tissue via a combination of microwave, vacuum and pressure treatment comprising the steps of fixing an organic sample, dehydrating and clearing the sample, and subsequently infiltrating and embedding the sample in a supporting medium to prepare it for basic Haematoxylin and Eosinstans and further techniques such as microwave staining, immunostaining, decalcification, hybridisation etc., for subsequent examination by light and electron microscopy.
Biopsies for diagnostic pathology and for anatomy pathology are presently prepared according to a conventional method, which is based on the following essential steps: to stop the --process of decay and to stabilise the tissue so as to protect it against physical and chemical rigours of the processing. free water contained in the specimen ist removed therefrom. During this procedure various cellular components are dissolved by the dehydrating fluids, such as lipids, which are extracted, and water soluble proteins, which are dissolved in aqueous alcohols. solvent, the so-called clearing agent. Clearing is the transition step between dehydration and infiltration with the supporting medium. Since many dehydrants are immiscible with said subsequently applied supporting medium, a solvent is used which is miscible both with the dehydrant and the embedding medium to facilitate the transition between dehydration and infiltration steps. infiltrating the tissue cavities and cells by the supporting substance and finally embedding the tissue in the medium which will provide sufficient external support during the ensuing processing.
These procedures show, however, a variety of disadvantages, such as a long processing time of the specimens which may amount up to 50 hours per sample. Furthermore, a huge amount of the dehydrating agent and the clearing agent has to be employed. In a normal procedure the specimens are treated several times with the dehydrating agent, e.g. ethanol in rising concentrations (up to 100% ethanol), and subsequently several times with the clearing agent in order to get rid of the dehydrating agent. Since large amounts of solvents have to be used, said solvents even being of high purity, the costs of such procedures are rather high.
A histoprocessing procedure with a shortened processing time is for example known, from the article "The Two-Step Vacuum-Microwave Method for Histoprocessing" by M. E. Boon et al., European Journal of Morphology, Vol. 33, No. 4, 1995, pages 349-358. The histoprocessing method of organic tissues disclosed therein includes the steps of fixing the tissue, dehydrating the sample, clearing the sample and embededing the sample in paraffin, whereby the dehydrating and the clearing of the sample are carried out simultaneously in 100%--isopropanol in a vacuum chamber and heated by microwaves. Isopropanol is used in this step because it is both a weak dehydrator and a claring agent. In this step the temperature is controlled at 55.degree. C. and the pressure at 0,04 MPa (400 mbar) so that the tissue can withstand the hazards of the treatment without adverse affects.
On the other hand it proved to be difficult in practice to properly process organic tissue samples having a substantial amount of lipids contained therein (fatty tissue). In this case, the free water to be removed is retained in the tissue to a large extent making the use of excessive amounts of dehydrating agent necessary, which eventually results in an inferior quality of the specimens. This fact was considered to be due to fat cells embodied in the respective specimens preventing a free migration of water out of the tissue.
An alternative technique has been developed to reduce the time delay between receipt of the biopsy material in the laboratory and the availability of the tissue for further examination, and to rapidly obtain thin slides of the respective material. The biopsies a
REFERENCES:
patent: 3889014 (1975-06-01), Kinney et al.
patent: 4839194 (1989-06-01), Malluche et al.
patent: 4891239 (1990-01-01), Dudley
patent: 4911915 (1990-03-01), Fredenburgh
patent: 5089288 (1992-02-01), Berger
patent: 5318795 (1994-06-01), Stokes et al.
patent: 5431952 (1995-07-01), Ocello
The Two-Step Vacuum-Microwave Method for Histoprocessing Mathilde E. Boon; C.H. Wals-Paap; F.A. Visinoni; L.P. Kok European Journal of Morphology, vol. 33, No. 4, 1995 Microwave Newsletter p. 349-358 XP 000614291 (no month).
Lautenschlager Werner
Visinoni Francesco
Dudash Diana
Lacasse Randy W.
Milestone S.r.l.
Strickland Wesley L.
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