Maria del Carmen Revelo-Cueva, Jorge Luis López, Nicolas Ernesto Ottone, Ana Belén Toaquiza Salazar,

Teaching morpho-functional sciences requires anatomical specimens, yet traditional preservation with formaldehyde poses health risks. Plastination provides safe, durable samples but faces limitations due to cost and regulatory restrictions on solvents and polymers. This pilot study evaluated ethanol, thinner, and platinum silicone as alternatives for producing plastinated specimens in Ecuador. Von Hagens’ plastination protocol was applied to chicken organs (heart, gizzard, and proventriculus), adapting dehydration–degreasing and forced impregnation phases. Organs were fixed in 10% formaldehyde for 15 days. Alternative solvents (ethanol, acetone, thinner) were tested at -20 °C; ethanol and acetone were selected for minimal volumetric shrinkage. Impregnation compared Biodur® (S10:S3) with platinum silicone, followed by curing with S6 Biodur® or manual catalyst application. Volumetric changes were recorded after dehydration and at process completion. Ethanol and acetone yielded lower shrinkage in hearts (12%) and gizzards (1–3%) versus thinner (43%). From a qualitative macroscopic standpoint, both the organs processed with Biodur® silicones (BS) and those treated with platinum silicone (PS) were dry, odorless, retained their overall anatomical shape, and could be handled without structural damage. However, the present study did not include a standardized scoring system for specimen quality assessment, which represents a limitation and should be addressed in future studies. Besides, the Bayesian statistical analyses performed on volumetric shrinkage did not provide sufficient evidence to indicate differences between the two polymers. Consequently, while these results may suggest possible trend toward the technically feasible of platinum silicone as an alternative, further in-depth studies with larger samples sizes are required. Nevertheless, the findings of this pilot study support the potential feasibility of an alternative dehydration protocol using ethanol.

Rafiqul Islam, Akash Saha John, Nasrin Sultana,

Cryodehydration is an efficient and cost-effective method for preserving the gross morphology of anatomical specimens. However, repeated freezing and thawing causes substantial cellular damage due to microruptures of the cell membrane. Objectives: Therefore, the present study was designed to investigate the role of cryoprotectant and controlled thawing protocols in optimizing cryodehydration technique for preparing cryodehydrated specimens, with particular focus on the preservation of histoarchitectural integrity. Method: To conduct this study, four healthy goats were used, labelled as G1-control, G2-formalin preserved, G3-cryodehydrated using routine protocol, and G4-cryodehydrated using glycerol as cryoprotectant and controlled thawing (4 °C). Results: Although the G4 specimens required more freeze-thaw cycle, both protocols (G3 and G4) resulted in excellent preservation of color, texture, and morphology. The specimens were soft, dry, odorless, lightweight, and durable. In the histological study, G2 yielded better histoarchitectural preservation resembling to the control while massive histoarchitectural alterations were observed in G3. These included noticeable thinning of the heart wall, increased spaces between cardiac myofibers, decreased bronchial and bronchiolar circumference and reduced alveolar surface area in the lungs, loss of hepatocytes and widened sinusoidal spaces in the liver, damage to both renal tubules and glomeruli, loss of lymphoid tissue in the spleen, and shrinkage of skeletal myofibers. In contrast, G4 demonstrated better preservation of histoarchitecture, maintaining cellular integrity along with distinct cytoplasmic and nuclear clarity. Conclusion: Based on these findings, it can be concluded that the use of glycerol as a cryoprotectant, in combination with controlled thawing at 4 °C, enhances the efficacy of the cryodehydration technique in preserving tissue histoarchitecture.