Background: We retrospectively analyzed 26 persistently asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carriers. Methods: Epidemiological and clinical characteristics from the 26 asymptomatic patients with positive results for SARS-CoV-2 ribonucleic acid testing were obtained. Results: Twenty-two patients (84.6%) correlated with clustering occurrence. The median period from contact to diagnosis and the last positive nucleic acid test was 19 (8–24 days) and 21.5 days (10–36 days), respectively. The median period from diagnosis to negative nucleic acid test was significantly different between patients with normal or atypical chest computed tomography (CT) findings (n = 16, 61.5%; 7.5 days [2–20 days]) and patients with typical ground-glass or patchy opacities on CT (n = 10, 38.5%; 12.5 days [8–22 days]; P < .01). Seven patients (70.0%) with initial positive nucleic acid test results had a negative result simultaneously with improved CT findings. Obvious improvement in CT findings was observed in 3 patients (30.0%) despite positive nucleic acid test results. Conclusions: In asymptomatic patients, changes in biochemical and inflammatory variables are small and changes on chest CT can occur. It is worth noting that the long existence of SARS-CoV-2 in some asymptomatic patients and false-negative results need to be considered in SARS-CoV-2 nucleic acid test.

Immortalization-upregulated protein (IMUP) plays a vital role in cell proliferation and tumor progression. However, its role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. Here, we select IMUP as an alternative gene based on GeneChip analysis of clinical PDAC tissues and transcriptome data from The Cancer Genome Atlas. IMUP expression is upregulated in PDAC tumor tissues. Moreover, high IMUP expression correlates with poor prognosis, while IMUP depletion inhibits PDAC cell proliferation and colony formation capacity in vitro, and decreases xenograft tumor growth in vivo. IMUP downregulation leads to cell-cycle arrest in the S phase. IMUP knockdown increases the expression of four-and-a-half LIM domain protein 1 (FHL1), which regulates the phosphorylation of cell division cycle 25A (CDC25A) by cycle checkpoint kinase 1 (CHK1) and promotes cytoplasmic distribution of CDC25A by interaction with 14–3-3ξ. Furthermore, FHL1 knockdown restores the effects induced by IMUP depletion. Liquid chromatography tandem mass spectrometry and immunoprecipitation analysis further show that IMUP interacts directly with nucleophosmin (NPM1) and enhances its stability. DNA methylation sequencing shows that FHL1 promoter methylation decreases when IMUP is downregulated. Overexpression of NPM1 can increase the methylation level of FHL1, thereby decreasing its expression. Our study provides a novel perspective on IMUP/NPM1/FHL1-mediated cell-cycle arrest by regulating CDC25A phosphorylation in PDAC. These findings may provide a new therapeutic target for PDAC. Graphical abstract

Various surgical methods impact the prognosis of patients with hepatocellular carcinoma (HCC) differently. However, clinical guidelines remain inconsistent and the relative importance of predictors of survival outcomes requires further evaluation. The present study aimed to rank the importance of predictive factors that impact the survival outcomes of patients with HCC and to compare the prognosis associated with different surgical methods based on data obtained from the Surveillance, Epidemiology and End Results database. To achieve these aims, the present study used a random forest (RF) model to detect important predictive factors associated with survival outcomes in patients with HCC. Cox regression analysis was used to compare different surgery methods. The variables included in the Cox regression model were selected based on the Gini index calculated by the RF model. Using the RF model, the present study demonstrated that surgery method, tumor size and age were the first, second and third most important factors associated with HCC prognosis, respectively. Overall, patients who underwent local tumor destruction [(hazard ratio (HR)=0.48; 95% confidence interval (CI), 0.45‑0.51; P<0.001)], wedge or segmental resection (HR, 0.31; 95% CI, 0.29‑0.33; P<0.001), lobectomy (HR, 0.29, 95% CI, 0.27‑0.31; P<0.001) or liver transplantation (HR, 0.16; 95% CI, 0.14‑0.17; P<0.001) demonstrated improved overall survival time compared with those treated with surgery, with a gradual decreasing trend observed in HRs. The present study demonstrated that the surgical method used is the most important predictor of the survival outcomes of patients with HCC. Liver transplantation resulted in the best prognosis for patients with HCC, except for those with undifferentiated tumors or distant metastasis.