Structural Basis for the Inhibition of SARS-CoV-2 Mpro D48N Mutant by Shikonin and PF-07321332.

Preventing the spread of SARS-CoV-2 and its variants is crucial in the fight against COVID-19. Inhibition of the main protease (Mpro) of SARS-CoV-2 is the key to disrupting viral replication, making Mpro a promising target for therapy. PF-07321332 and shikonin have been identified as effective broad-spectrum inhibitors of SARS-CoV-2 Mpro. The crystal structures of SARS-CoV-2 Mpro bound to PF-07321332 and shikonin have been resolved in previous studies. However, the exact mechanism regarding how SARS-CoV-2 Mpro mutants impact their binding modes largely remains to be investigated. In this study, we expressed a SARS-CoV-2 Mpro mutant, carrying the D48N substitution, representing a class of mutations located near the active sites of Mpro. The crystal structures of Mpro D48N in complex with PF-07321332 and shikonin were solved. A detailed analysis of the interactions between Mpro D48N and two inhibitors provides key insights into the binding pattern and its structural determinants. Further, the binding patterns of the two inhibitors to Mpro D48N mutant and wild-type Mpro were compared in detail. This study illustrates the possible conformational changes when the Mpro D48N mutant is bound to inhibitors. Structural insights derived from this study will inform the development of new drugs against novel coronaviruses.

Meta-Analyses of Association Between BRAF(V600E) Mutation and Clinicopathological Features of Papillary Thyroid Carcinoma.

BACKGROUND/AIMS: The function of BRAF V600E as a prognostic biomarker continues controversial by reason of conflicting results in the published articles. METHODS: A systematical literature search for relevant articles was performed in PubMed, Cochrane Library, Google Scholar, Medline and Embase updated to August 5, 2015. The Chi-square test and I2 were employed to examine statistical heterogeneity. Pooled ORs with their corresponding 95% confidence intervals (95%CIs) were calculated to assess the relationship between clinicopathological features and BRAF(V600E) mutation. Subgroup analyses by ethnicity were also performed to explore the potential sources of heterogeneity. Furthermore, publication bias was detected using the funnel plot and all statistical analyses were conducted by the software of R 3.12. RESULTS: Of 25,241 cases with PTC, 15,290 (60.6%) were positive for BRAF mutation and 9,951 (39.4%) were tested negative for BRAF mutation. Negative status of BRAF(V600E) mutation negative was significantly associated with gender (OR = 0.90, 95%CI = 0.83-0.97) and concomitant hashimoto thyroiditis (OR = 0.53, 95%CI = 0.43-0.64). By contrast, positive status of BRAF(V600E) mutation was a significant predictor of multifocality (OR = 1.23; 95%CI = 1.14-1.32), extrathyroidal extension (OR = 2.23; 95%CI = 1.90-2.63), TNM stage (OR = 1.67; 95%CI = 1.53-1.81), lymph node metastasis (OR = 1.67; 95%CI = 1.45-1.93), vascular invasion (OR = 1.47; 95%CI = 1.22-1.79) and recurrence/persistence (OR = 2.33; 95%CI = 1.71-3.18). However, there was no significant association between BRAF(V600E) mutation and factors including age > 45 (OR = 0.98; 95%CI = 0.89-1.07), tumor size (OR = 0.84; 95%CI = 0.64-1.09) and distant metastasis (OR = 1.23; 95%CI = 0.67-2.27). CONCLUSION: This meta-analysis confirmed significant associations between BRAF(V600E) mutation and female gender, multifocality, ETE, LNM, TNM stage, concomitant hashimoto thyroiditis, vascular invasion and recurrence/persistence, suggesting the predictive value of BRAF(V600E) mutation for PTC prognosis.

[Treatment of traumatic pseudoaneurysm of head and neck (report of 4 cases)].

OBJECTIVE: To discuss the clinical features, diagnosis and treatment of traumatic pseudoaneurysm. METHOD: We report 4 unusual cases of traumatic Pseudoaneurysms of the artery of head and neck. The data of the 4 cases was analysed retrospectively. RESULT: Four patients were with history of trauma and traumatic pseudoaneurysm were diagnosed by CT and DSA. Two of them accepted interventional vascular therapy, the others accepted surgical operation. Both methods are safe and effective. CONCLUSION: Traumatic pseudoaneurysms of the artery of head and neck are rare but potentially lethal. The diagnosis is not difficult. The interventional treatment should be the first choice if possible, while the surgical approach is another choice. Doctors should try to repair the arterial wall, to keep the artery patency and to decrease the unnecessary complications.