Preserved embalmed bodies prove that long-term embalming of a human body is possible under certain conditions. Researchers face problems, such as changes in skin color, brought about by changes in melanin due to UV radiation or formaldehyde, which reduces hemoglobin in tissues, and other factors. Changes in tissue volume, drying out, hydrolysis and oxidation of fats, decalcification of bones, or the possible presence of microorganisms in the form of molds or fungi are major problems to deal with. In the initial stages, preservation with formaldehyde, bleaching of brown skin spots with hydrogen peroxide, or treatment of parchment-like spots with water, dilute acetic acid, and hydrogen peroxide is necessary (Lopukhin, 1997). Changes in tissue volume, e.g. swelling, are treated with concentrated ethanol. Constant monitoring and automatic regulation of temperature and humidity in the sarcophagus is necessary (Kozeltsev and Romakov, 2000). Further, non-contact methods for the control of skin condition and color, as well as relief and volume of soft tissues, or the application of advanced imaging methods for monitoring internal structures, have been developed and improved. Last but not least, the continuous analysis of the embalming solution from the overalls, and the collection of tissue specimen to assess the state of cytological and histological structure are of paramount importance. For example, in a specific physiochemical analysis of the skin and epidermis, diffusion parameters of tissue impregnation were found. The histological structure of the skin had been preserved with a number of structural changes in the stratum corneum, cell layers, and dermis, such as disorders of karyolysis, decreased volume of nuclei, decreased DNA content, histones, or RNA concentration. The extent of the changes is determined by the duration of the embalming and the properties of the skin. Substances released during UV absorption, or morphological damage to cells or threshold levels of structural integration of the cell organelle system were also detected (Tomashevich, 1997). A major disadvantage of the Soviet-Russian embalming method is the enormous financial cost of the establishment and operation of the technical facilities.
Postscript
In the 1990s, the staff of the Lenin Mausoleum laboratory studied the effects of the embalming process on the state of epidermal nucleoproteins, using histochemical detection of nucleic acids and proteins in embalmed materials. They also explored the UV absorbers passing into the fluid during the embalming of skin and muscle tissues, using methods of mathematical physics in order to solve problems with the diffusion of preservative components, or using mathematical models of the process of preservative component diffusion in various tissues, and many other topics (Tomashevich and Nikitina, 1989). No other institution in the world has achieved such knowledge in the study of thanatochemical and microscopic changes in long-term embalmed tissues. Currently, the same team are working on the development of new methods for a non-destructive quantitative assessment of the main components in aqueous solutions containing potassium acetate and glycerin, with the use of Quantitative 1H-NMR spectroscopy (Proton Nuclear Magnetic Resonance) (Abramov 2018; Agrafenin, 2018) or thermogravimetry (Polakov, 2019). While there are a number of research perspectives concerning the long-term preservation of embalmed tissues, it may be assumed that no other laboratory will address these issues at such a level of excellence in the foreseeable future.
It is important to produce basic information on the anatomy of the male reproductive system, since it has considerable significance in breeding, in order to make an accurate pathological diagnosis, and to provide effective clinical treatment of diseases (AlLugami et al, 2017). The obtained urethral corrosion cast allowed visual inspection of the urethra, which led to better understanding of the anatomy needed to resolve clinical and surgical pathological conditions.
The main characteristic of the obtained three-dimensional model was maintenance of shape of the surface of all the portions of the urethra. This enabled the identification of four morphologically distinct portions of the canine male urethra, contrary to the two (Getty, 1986; Dyce et al., 2010) or three (Dellman, 1993) portions for domestic animals previously described in the scientific literature.
The total replication model obtained can also be useful to describe the total volume capability of the urethra in each portion; other studies have found a significantly variation of the urethral lumen during spontaneous urination (AlLugami et al., 2017). As mentioned previously, a dilation of the prostatic portion of the urethra was found in our study (Poogird and Wood, 1986).
