Self-assembly of rigid building blocks with explicit shape and symmetry is substantially influenced by the geometric factors and remains largely unexplored. We report the selective assembly behaviors of a class of precisely defined, nanosized giant tetrahedra constructed by placing different polyhedral oligomeric silsesquioxane (POSS) molecular nanoparticles at the vertices of a rigid tetrahedral framework. Designed symmetry breaking of these giant tetrahedra introduces precise positional interactions and results in diverse selectively assembled, highly ordered supramolecular lattices including a Frank-Kasper A15 phase, which resembles the essential structural features of certain metal alloys but at a larger length scale. These results demonstrate the power of persistent molecular geometry with balanced enthalpy and entropy in creating thermodynamically stable supramolecular lattices with properties distinct from those of other self-assembling soft materials.

Background The worldwide spread of SARS-CoV-2 has infected millions of people leading to over 0.3 million mortalities. The disruption of sodium homeostasis, tends to be a common occurrence in patients with COVID-19. Methods and results A total of 1,254 COVID-19 patients comprising 124 (9.9%) hyponatremic patients (under 135 mmol/L) and 30 (2.4%) hypernatremic patients (over 145 mmol/L) from three hospitals in Hubei, China, were enrolled in the study. The relationships between sodium balance disorders in COVID-19 patients, its clinical features, implications, and the underlying causes were presented. Hyponatremia patients were observed to be elderly, had more comorbidities, with severe pneumonic chest radiographic findings. They were also more likely to have a fever, nausea, higher leukocyte and neutrophils count, and a high sensitivity C-reactive protein (HS-CRP). Compared to normonatremia patients, renal insufficiency was common in both hyponatremia and hypernatremia patients. In addition, hyponatremia patients required extensive treatment with oxygen, antibiotics, and corticosteroids. The only significant differences between the hypernatremia and normonatremia patients were laboratory findings and clinical complications, and patients with hypernatremia were more likely to use traditional Chinese medicine for treatment compared to normonatremia patients. This study indicates that severity of the disease, the length of stay in the hospital of surviving patients, and mortality were higher among COVID-19 patients with sodium balance disorders. Conclusion Sodium balance disorder, particularly hyponatremia, is a common condition among hospitalized patients with COVID-19 in Hubei, China, and it is associated with a higher risk of severe illness and increased in-hospital mortality.

Long noncoding RNAs, a newly identified class of noncoding RNAs, are important regulators of gene expression in innate immunity. We report in this study that the transcription of FIRRE, a conserved long noncoding RNA between humans and mice, is controlled by NF-κB signaling in macrophages and intestinal epithelial cells. Functionally, FIRRE appears to positively regulate the expression of several inflammatory genes in macrophages or intestinal epithelial cells in response to LPS stimulation via posttranscriptional mechanisms. Specifically, FIRRE physically interacts with heterogeneous nuclear ribonucleoproteins U, regulating the stability of mRNAs of selected inflammatory genes through targeting the AU-rich elements of their mRNAs in cells following LPS stimulation. Therefore, our data indicate a new regulatory role for NF-κB–responsive FIRRE in the posttranscriptional regulation of inflammatory genes in the innate immune system.

Chordoma is a rare bone tumor with an unknown etiology and high recurrence rate. Here we conduct whole genome sequencing of 80 skull-base chordomas and identify PBRM1, a SWI/SNF (SWItch/Sucrose Non-Fermentable) complex subunit gene, as a significantly mutated driver gene. Genomic alterations in PBRM1 (12.5%) and homozygous deletions of the CDKN2A/2B locus are the most prevalent events. The combination of PBRM1 alterations and the chromosome 22q deletion, which involves another SWI/SNF gene (SMARCB1), shows strong associations with poor chordoma-specific survival (Hazard ratio [HR] = 10.55, 95% confidence interval [CI] = 2.81-39.64, p = 0.001) and recurrence-free survival (HR = 4.30, 95% CI = 2.34-7.91, p = 2.77 × 10−6). Despite the low mutation rate, extensive somatic copy number alterations frequently occur, most of which are clonal and showed highly concordant profiles between paired primary and recurrence/metastasis samples, indicating their importance in chordoma initiation. In this work, our findings provide important biological and clinical insights into skull-base chordoma.