scholarly journals A new Heterodontosaurus specimen elucidates the unique ventilatory macroevolution of ornithischian dinosaurs

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Viktor J Radermacher ◽  
Vincent Fernandez ◽  
Emma R Schachner ◽  
Richard J Butler ◽  
Emese M Bordy ◽  
...  

Ornithischian dinosaurs were ecologically prominent herbivores of the Mesozoic Era that achieved a global distribution by the onset of the Cretaceous. The ornithischian body plan is aberrant relative to other ornithodiran clades, and crucial details of their early evolution remain obscure. We present a new, fully articulated skeleton of the early branching ornithischian Heterodontosaurus tucki. Phase-contrast enhanced synchrotron data of this new specimen reveal a suite of novel postcranial features unknown in any other ornithischian, with implications for the early evolution of the group. These features include a large, anteriorly projecting sternum; bizarre, paddle-shaped sternal ribs; and a full gastral basket – the first recovered in Ornithischia. These unusual anatomical traits provide key information on the evolution of the ornithischian body plan and suggest functional shifts in the ventilatory apparatus occurred close to the base of the clade. We complement these anatomical data with a quantitative analysis of ornithischian pelvic architecture, which allows us to make a specific, stepwise hypothesis for their ventilatory evolution.

2021 ◽  
Vol 10 (9) ◽  
pp. 1850
Author(s):  
Seun-Ah Lee ◽  
Sang-Won Jo ◽  
Suk-Ki Chang ◽  
Ki-Han Kwon

This study aims to investigate the diagnostic ability of the contrast-enhanced 3D T1 black-blood fast spin-echo (T1 BB-FSE) sequence compared with the contrast-enhanced 3D T1-spoiled gradient-echo (CE-GRE) sequence in patients with facial neuritis. Forty-five patients with facial neuritis who underwent temporal bone MR imaging, including T1 BB-FSE and CE-GRE imaging, were examined. Two reviewers independently assessed the T1 BB-FSE and CE-GRE images in terms of diagnostic performance, and qualitative (diagnostic confidence and visual asymmetric enhancement) and quantitative analysis (contrast-enhancing lesion extent of the canalicular segment of the affected facial nerve (LEC) and the affected side-to-normal signal intensity ratio (rSI)). The AUCs of each reviewer, and the sensitivity and accuracy of T1 BB-FSE were significantly superior to those of CE-GRE (p < 0.05). Regarding diagnostic confidence and visual asymmetric enhancement, T1 BB-FSE tended to be rated greater than CE-GRE (p < 0.05). Additionally, in quantitative analysis, LEC and rSI of the canalicular segment on T1 BB-FSE were larger than those on CE-GRE (p < 0.05). The T1 BB-FSE sequence was significantly superior to the CE-GRE sequence, with more conspicuous lesion visualization in terms of both qualitative and quantitative aspects in patients with facial neuritis.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Jun Nakamura ◽  
Takamitsu Nakamura ◽  
Juntaro Deyama ◽  
Daisuke Fujioka ◽  
Ken-ichi Kawabata ◽  
...  

Introduction: Extensive neovascularization in atherosclerotic plaque has been shown to be associated with plaque progression and instability, leading to atherosclerotic cardiovascular events. Contrast-enhanced ultrasound (CEUS) of the carotid artery is a potential technique for imaging plaque neovascularization. Hypothesis: Assessment of intra-plaque neovascularization of the carotid artery using quantitative analysis of CEUS provides prognostic information in patients with coronary artery disease (CAD). Methods: This study included 206 patients with stable CAD and with carotid intima-media thickness (IMT) > 1.1 mm. They underwent a CEUS examination of the carotid artery and were followed-up prospectively for < 38 months or until a cardiac event (cardiac death, non-fatal myocardial infarction [MI], unstable angina pectoris [uAP] requiring unplanned coronary revascularization, or heart failure requiring hospitalization). The degree of contrast signals measured within the carotid plaque after the intravenous injection of contrast material was quantified by calculating the increase in mean gray scale level within the region of interest of the carotid plaque, expressed as plaque enhanced intensity. Results: During the follow-up period (3 - 38 months, mean 22.8 ± 11.8 months), 31 events occurred (2 cardiac deaths, 7 non-fatal MIs, 16 uAP, and 6 heart failure). Multivariate Cox proportional hazards analysis showed that plaque enhanced intensity was a significant predictor of cardiac events independent of traditional risk factors (HR, 1.52; 95% CI, 1.20 - 1.94; p = 0.001). The addition of plaque enhanced intensity had a significant incremental effect on the area under the ROC curve (AUC) generated using baseline model of traditional risk factors (AUC: baseline model 0.69 vs. baseline model + plaque enhanced intensity 0.78, p = 0.03). The addition of the plaque enhanced intensity to the baseline risk factors resulted in net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.58, p = 0.003; and IDI 0.078, p = 0.03). Conclusions: The assessment of carotid plaque neovascularization using quantitative analysis of CEUS may be useful for risk stratification in patients with CAD.


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