Unusual intraosseous fossilized soft tissues from the Middle Triassic Nothosaurus bone.

Fossilized soft tissues, occasionally found together with skeletal remains, provide insights to the physiology and functional morphology of extinct organisms. Herein, we present unusual fossilized structures from the cortical region of bone identified in isolated skeletal remains of Middle Triassic nothosaurs from Upper Silesia, Poland. The ribbed or annuli-shaped structures have been found in a sample of partially demineralized coracoid and are interpreted as either giant red blood cells or as blood vessel walls. The most probable function is reinforcing the blood vessels from changes of nitrogen pressure in air-breathing diving reptiles. These structures seem to have been built of extensible muscle layers which prevent the vessel damage during rapid ascent. Such suspected function presented here is parsimonious with results of previous studies, which indicate rarity of the pathological modification of bones associated with decompression syndrome in Middle Triassic nothosaurs.

Spectroscopic Studies on Organic Matter from Triassic Reptile Bones, Upper Silesia, Poland.

Fossil biomolecules from an endogenous source were previously identified in Cretaceous to Pleistocene fossilized bones, the evidence coming from molecular analyses. These findings, however, were called into question and an alternative hypothesis of the invasion of the bone by bacterial biofilm was proposed. Herewith we report a new finding of morphologically preserved blood-vessel-like structures enclosing organic molecules preserved in iron-oxide-mineralized vessel walls from the cortical region of nothosaurid and tanystropheid (aquatic and terrestrial diapsid reptiles) bones. These findings are from the Early/Middle Triassic boundary (Upper Roetian/Lowermost Muschelkalk) strata of Upper Silesia, Poland. Multiple spectroscopic analyses (FTIR, ToF-SIMS, and XPS) of the extracted "blood vessels" showed the presence of organic compounds, including fragments of various amino acids such as hydroxyproline and hydroxylysine as well as amides, that may suggest the presence of collagen protein residues. Because these amino acids are absent from most proteins other than collagen, we infer that the proteinaceous molecules may originate from endogenous collagen. The preservation of molecular signals of proteins within the "blood vessels" was most likely made possible through the process of early diagenetic iron oxide mineralization. This discovery provides the oldest evidence of in situ preservation of complex organic molecules in vertebrate remains in a marine environment.

Pathomorphological pattern of paravertebral muscles of rabbits after long-term experimental electrostimulation.

The objective of this study was to identify the histopathological features of paravertebral muscles after long-term Lateral Electrical Surface Stimulation (LESS). LESS has been applied for the treatment of idiopathic scoliosis in children and adolescents. Former studies reported the negative effect on the mental state of treated patients, as well as functional disturbances of organs, endocrine glands, and muscle metabolism. The experiment was performed on rabbits (aged 3.5 months), (n = 5 in treated, n = 5 in non-treated group). Stimulation was performed using electrical stimulator SCOL-2. The rabbits were stimulated with the traditional long-term lateral electrical surface stimulation (LESS) method as in clinical applications for children and adolescents. After microscopic examination, atrophy of fibers and cross striation of paravertebral muscles were seen, as well as degenerative lesions, necrosis, and hyperemia. Furthermore, proliferation of nuclei and infiltration of monocytogenic phagocytes mononuclear cells were observed, as well as a wide differentiation of glycosoaminoglycanes in muscle fibers on the stimulated side. However, within the tissue undergoing regression, this resulted in a clear decrease in glycosoaminoglycane levels. The observed lesions may indicate that the damage to the neuromuscular system is an effect of long-term LESS application. Thus, standard LESS therapy may deepen idiopathic scoliosis.