CXCL10 May Be Responsible for Susceptibility to Pulmonary Embolism in COVID-19 Patients.

Background: Although the potential of coronavirus disease 2019 (COVID-19) patients to develop pulmonary embolism (PE) is widely recognized, the underlying mechanism has not been completely elucidated. This study aimed to identify genes common to COVID-19 and PE to reveal the underlying pathogenesis of susceptibility to PE in COVID-19 patients. Methods: COVID-19 genes were obtained from the GEO database and the OMIM, CTD, GeneCards, and DisGeNET databases; PE genes were obtained from the OMIM, CTD, GeneCards, and DisGeNET databases. We overlapped the genes of COVID-19 and PE to obtain common genes for additional analysis, including functional enrichment, protein-protein interaction, and immune infiltration analysis. Hub genes were identified using cytoHubba, a plugin of Cytoscape, and validated using the independent datasets GSE167000 and GSE13535. The genes validated by the above datasets were further validated in clinical samples. Results: We obtained 36 genes shared by PE and COVID-19. Functional enrichment and immune infiltration analyses revealed the involvement of cytokines and immune activation. Five genes (CCL2, CXCL10, ALB, EGF, and MKI67) were identified as hub genes common to COVID-19 and PE. CXCL10 was validated in both independent datasets (GSE167000 and GSE13535). Serum levels of CXCL10 in the COVID-19 group and the COVID-19 combined with PE group were significantly higher than those in the healthy control group (P<0.001). In addition, there were significant differences between the COVID-19 group and the COVID-19 combined with PE group (P<0.01). Conclusion: Our study reveals common genes shared by PE and COVID-19 and identifies CXCL10 as a possible cause of susceptibility to PE in COVID-19 patients.

Decreased mitochondrial D-loop region methylation mediates an increase in mitochondrial DNA copy number in CADASIL.

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a typical neurodegenerative disease associated with mitochondrial dysfunction. Methylation of the D-loop region and mitochondrial DNA copy number (mtDNAcn) play a critical role in the maintenance of mitochondrial function. However, the association between D-loop region methylation, mtDNAcn and CADASIL remains unclear. METHODS: Overall, 162 individuals were recruited, including 66 CADASIL patients and 96 age- and sex-matched controls. After extracting genomic DNA from the peripheral white blood cells, levels of D-loop methylation and mtDNAcn were assessed using MethylTarget sequencing and real-time PCR, respectively. RESULTS: We observed increased mtDNAcn and decreased D-loop methylation levels in CADASIL patients compared to the control group, regardless of gender stratification. Besides, we found a negative correlation between D-loop methylation levels and mtDNAcn. Mediation effect analysis shows that the proportion of the association between mtDNAcn and CADASIL that is mediated by D-loop methylation is 11.6% (95% CI 5.6, 22.6). After gender stratification, the proportions of such associations that are mediated by D-loop methylation in males and females were 7.2% (95% CI 2.4, 19.8) and 22.0% (95% CI 7.4, 50.1), respectively. CONCLUSION: Decreased methylation of the D-loop region mediates increased mtDNAcn in CADASIL, which may be caused by a compensatory mechanism of mitochondrial dysfunction in patients with CADASIL.

LDHB may be a significant predictor of poor prognosis in osteosarcoma.

Osteosarcoma is the most common primary malignant bone tumor in children and young adults. Lactate dehydrogenase (LDH) is considered as the key glycolytic enzyme and involved in tumor initiation and metabolism. Here, we firstly found that LDHB was highly expressed in osteosarcoma cell lines. Expression profiling indicated that LDHB mRNA was elevated in osteosarcoma tissues with metastasis versus without metastasis, and LDHB high expression predicted a poor prognosis in patients. After LDHB knockdown by siRNA transfection, cell growth and proliferation were inhibited and presented a dose-dependent cell death via MTT assay. Meanwhile, wound healing and matrigel invasion assay revealed that LDHB knockdown inhibited migration and invasion activities in osteosarcoma cells. We further constructed tissue microarray in 40 osteosarcoma tissues. Correlation between LDHB and clinicopathological features indicated that LDHB expressions were associated with tumor TNM stage, recurrence and survival. Kaplan-Meier survival curve revealed that overall survival was significantly decreased in patients with high expression of LDHB. Patients with recurrence or advanced stage showed an increased LDHB, suggesting that increased LDHB was closely associated with a poor prognosis in osteosarcoma patients. Thus, LDHB can be considered as a prognostic marker for tumor recurrence and poor overall survival in osteosarcoma.

Phenoloxidase and its zymogen are required for the larval-pupal transition in Bactrocera dorsalis (Diptera: Tephritidae).

Phenoloxidases (POs) play a key role in melanin production, are involved in invertebrate immune mechanisms, and are considered important enzymes in the insect development process. In the present study, we report the developmental stage and tissue-specific expression patterns of BdPPO1 and PO activity from Bactrocera dorsalis. The results showed that the activity of PO and its zymogen expression were closely related to the development of B. dorsalis during the larval-pupal transition, particularly in the integument. Additionally, biochemical characterization showed that PO from different developmental stages and tissues all had maximum activity at pH 7.5 and 37°C. After feeding a metal ion-containing artificial diet, the activity of PO and expression of BdPPO1 were significantly increased, indicating that PO was a metalloprotein and it could be activated by Zn2+, Mg2+, Ca2+, and Cu2+. The functional analysis showed that the expression of BdPPO1 could be regulated by 20-hydroxyecdysone (20E) after injection. Furthermore, injection of the double-stranded RNA of BdPPO1 into the 3rd instar larvae significantly reduced mRNA levels after 24 h and 48 h, and resulted in a lower pupation rate and abnormal phenotype. These results expand the understanding of the important role of PO and its zymogen in the growth of B. dorsalis.