Blood Clots in Dinosaur Bones
Figure 8a: Ground section, Triceratops vertebra (HCTV-22). Haversian canals are almost completely blocked by a dark amorphous material (arrows). Aster- isks indicate small openings within clots. Light microscopy, brightfield. Scale bar, 100 µm.
Figure 8b: Same view under UV epi-fluorescence (UVFL). Clots are marked by a brightly reflective layer (BRL) with internal opaque chunks, which completely fill the vessel canal and abut closely to vessel canal walls. Asterisks indicate small openings within the clots. Clots are characterized by sharp margins (dense line, black arrows), and do not spread into adjacent bone. Scale bar, 100 µm.
Later, workers incubated specimens of chicken bone
microvasculature in ferrous chloride (instead of hemoglobin) to initiate non-enzymatic crosslinks in vessel collagen and elastin [10]. Any potential problems associated with the pres- ence of real-world thrombin, prothrombin, fibrinogen, fibrin, cell and tissue factors, etc. were eliminated. Vessel sections were examined, post-treatment, by SR-FTIR, and signs of increased intramolecular crosslinking of structural proteins were observed. Tese were compared with similar crosslinks found in untreated, sectioned dinosaur vessels. Boatman et al. conclude, “Exposure of extant chicken type I collagen tissues to Fenton chemistry and transition metal-catalyzed glycation rapidly induces chemical modifications observed in the dino- saur tissues studied here … these molecular features confer resistance to degradation in tissues that possess them…” [10].
2020 September •
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Figure 9a, 9b: Triceratops horn (HCTH-03). Canals are completely clotted. Under UV (9b), a brightly reflective homogenous layer encases and surrounds darker crystallized shards, probably crystallized blood products. These darker shards are never found outside of the brightly reflective material and are usually characterized as highly angular particles under 20 µm in width, although many are rounded (see white arrows, Figure 11b). Scale bar, 100 µm.
As mentioned, thrombosis is oſten initiated within the vascu-
lature of animals as a response to trauma including major tissue or head (brain or cranial) injury and most particularly in drown- ing cases
[38,39]. Trauma-related disseminated intravascular
coagulation (DIC) occurs when fibrinogen is cleaved into fibrin (as above) and deposited systemically into the vasculature, form- ing microvascular clots throughout the body [40]. DIC might also be exacerbated by an underlying disorder that triggers and then maintains coagulation in the microvasculature [41]. Studies also
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