Genetic variants in Chinese patients with sporadic Stanford type A aortic dissection.

BACKGROUND: Genetic disorders are strongly associated with aortic disease. However, the identities of genetic mutations in sporadic Stanford type A aortic dissection (STAAD) are not clear. The present study analysed the possible genetic mutations of the known pathogenic genes of aortic disease and the clinical characteristics in patients with sporadic STAAD. METHODS: We analysed genetic mutations in 26 genes that underlie aortic aneurysms and dissections in 100 sporadic STAAD patients and 568 healthy controls after whole-genome sequencing (WGS). Clinical features and in-hospital death were determined in all STAAD patients. RESULTS: In total, 60 suspicious pathogenic mutations (56 novel and 4 previously reported) in 19 genes were identified in 50% (50/100) of patients, and 14 patients had more than 1 mutation. The ascending aortic diameter was extended in patients with mutations (49.1±12.3 vs. 43.7±11.2 mm, P=0.023), and the DeBakey type I phenotype was more common in patients with mutations in genes that coded extracellular matrix (ECM) components than in patients with mutations in other genes (96.6% vs. 66.7%, P=0.007). Patients with fibrillin-1 (FBN1) mutations were younger than patients without FBN1 mutations (44.7±11.0 vs. 53.5±12.1, P=0.030). Subgroup analyses revealed an increased risk of in-hospital mortality in mutation carriers (44.4% vs. 10.5%, P=0.029) but only in patients who received conservative treatment. CONCLUSIONS: Half of Chinese patients with a sporadic form of STAAD may carry mutations in known pathogenic genes of aortic disease, and these patients may exhibit distinct clinical features and poor clinical outcomes with the use of conservative treatment.

Photocontrol of a microbubble in a fiber-based hollow microstructure.

We experimentally demonstrated a novel photocontrol scheme of a microbubble. The microbubble was confined in a fiber-based hollow microstructure and its movement was driven by the laser-induced photothermal Marangoni force. The position of the microbubble was controlled at a micrometer scale by simply adjusting the drive laser power. This scheme permitted the firsthand control of a microbubble with a divergent single laser beam. As a practical demonstration, we proposed a variable fiber all-optical attenuator by exploiting the total internal reflection on the surface of the photo-controlled microbubble to modulate the target light beam. The experimental results showed that such a compact fiber attenuator possessed a low insertion loss of 0.83 dB, a maximum extinction ratio of 28.7 dB, and had potential to be integrated into the lab-on-a-chip for the modulation of the light beam power.