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Dengue virus (DENV) is a mosquito-borne pathogen that causes a spectrum of diseases including life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Vascular leakage is a common clinical crisis in DHF/DSS patients and highly associated with increased endothelial permeability. The presence of vascular leakage causes hypotension, circulatory failure, and disseminated intravascular coagulation as the disease progresses of DHF/DSS patients, which can lead to the death of patients. However, the mechanisms by which DENV infection caused the vascular leakage are not fully understood. This study reveals a distinct mechanism by which DENV induces endothelial permeability and vascular leakage in human endothelial cells and mice tissues. We initially show that DENV2 promotes the matrix metalloproteinase-9 (MMP-9) expression and secretion in DHF patients’ sera, peripheral blood mononuclear cells (PBMCs), and macrophages. This study further reveals that DENV non-structural protein 1 (NS1) induces MMP-9 expression through activating the nuclear factor κB (NF-κB) signaling pathway. Additionally, NS1 facilitates the MMP-9 enzymatic activity, which alters the adhesion and tight junction and vascular leakage in human endothelial cells and mouse tissues. Moreover, NS1 recruits MMP-9 to interact with β-catenin and Zona occludens protein-1/2 (ZO-1 and ZO-2) and to degrade the important adhesion and tight junction proteins, thereby inducing endothelial hyperpermeability and vascular leakage in human endothelial cells and mouse tissues. Thus, we reveal that DENV NS1 and MMP-9 cooperatively induce vascular leakage by impairing endothelial cell adhesion and tight junction, and suggest that MMP-9 may serve as a potential target for the treatment of hypovolemia in DSS/DHF patients., Author summary DENV is the most common mosquito-transmitted viral pathogen in humans. In general, DENV-infected patients are asymptomatic or have flu-like symptoms with fever and rash. However, in severe cases of DENV infection, the diseases may progress to dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), the leading causes of morbidity and mortality in school-age children in tropical and subtropical regions. DENV-induced vascular leakage is characterized by enhanced vascular permeability without morphological damage to the capillary endothelium. This study reveals a possible mechanism by which DENV NS1 and MMP-9 cooperatively induce vascular leakage. NS1 also recruits MMP-9 to degrade β-catenin, ZO-1, and ZO-2 that leads to intervene endothelial hyperpermeability in human endothelial cells and mouse vascular. Moreover, the authors further reveal that DENV activates NF-κB signaling pathway to induce MMP-9 expression in patients, mice, PBMC, and macrophages though NS1 protein. This study would provide new in signs into the pathogenesis of DENV infection, and suggest that MMP-9 may act as a drug target for the prevention and treatment of DENV-associated diseases.

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) with a complex aetiology that commonly recurs. Most drugs for UC treatment interfere with metabolism and immune responses, often causing some serious adverse reactions. Therefore, the development of alternative treatments, including nutritional supplements and probiotics, have been one of the main areas of current research due to fewer side effect. As both a Chinese medicine and a food, edible bird’s nest (EBN) has high nutritional value. Modern pharmacological studies have shown that it has anti-inflammatory, immunoregulatory, antiviral and neuroprotective effects. In this study, UC was induced with dextran sulfate sodium (DSS) to investigate the protective effect of EBN on colitis mice and the related mechanism. The body weight, faecal morphology and faecal occult blood results of mice were recorded every day from the beginning of the modelling period. After the end of the experiment, the length of the colon was measured, and the colon was collected for histopathological detection, inflammatory factor detection and immunohistochemical detection. Mouse spleens were dissected for flow cytometry. The results showed that in mice with colitis, EBN improved symptoms of colitis, reduced colonic injury, and inhibited the increases in the levels of the pro-inflammatory cytokines IL-1β and TNF-α. The T helper 17 (Th17)/regulatory T (Treg) cell balance was restored by decreasing the expression of IL-17A and IL-6 in intestinal tissues, increasing the expression of TGF-β, and decreasing the number of Th17 cells in each EBN dose group. These findings suggest that EBN has a protective effect on DSS-mediated colitis in mice, mainly by restoring the Th17/Treg cell balance.

Thyroid cancer (TC) is the most common endocrine malignant disease with a rising morbidity year by year. Accumulating studies have shown that microRNAs (miRNAs) play a regulatory role in the progression of various tumors, but the molecular regulatory mechanism of miR-196a-2 in TC is still unknown. qRT-PCR was employed to measure the expression of miR-196a-2 and NRXN1 mRNA in TC cells, while western blot was used to detect the protein expression of NRXN1. CCK-8, colony formation and flow cytometry assays were used to measure cell proliferation and apoptosis of TC cells. Dual-luciferase reporter gene assay was used to predict and verify the targeted binding relationship between miR-196a-2 and NRXN1. Our study results manifested that miR-196a-2 was dramatically overexpressed in cells of TC, while NRXN1 was lowly expressed. miR-196a-2 could promote cell proliferation and inhibit cell apoptosis of TC. Additionally, miR-196a-2 could also target and inhibit the expression of NRXN1. Silencing NRXN1 could reverse the inhibitory effect of miR-196a-2 downregulation on cell proliferation of TC, as well as the promoting effect on cell apoptosis. In a conclusion, we found that miR-196a-2 could promote cell proliferation and inhibit cell apoptosis of TC by targeting NRXN1. Therefore, miR-196a-2/NRXN1 is potential to be a molecular therapeutic target for TC.

Background: Osteosarcoma is a rare type of bone tumor, and this study aimed to assess the clinicopathologic features and prognoses of osteosarcoma patients. Methods: Clinicopathologic and survival data of 1025 patients between 2010 and 2016, 230 between 2008 and 2009 were downloaded and analyzed from the SEER database. Patients’ survival was analyzed using the Kaplan-Meier analysis; prognostic factors were assessed using the Cox regression hazards model. The 1-, 3-, and 5-year survival rates were estimated with nomogram. Competitive risk models were used to identify prognostic risk factors related to endpoint events of osteosarcoma patients. Results: Overall, 722 samples were obtained from the extremities, 134 from the axial bones, and 119 from the cranial and mandible in SEER (2010-2016 cohort). After the preliminary diagnosis, the median survival time of patients with osteosarcoma was 39 months, and the 1-, 3-, and 5-year survival rates were 87.3%, 67.2%, and 58.0%, respectively (P < 0.001). The competitive risk model revealed no competitive risks of the endpoint event. Conclusion: Our study found out the prognostic factors in patients with Osteosarcoma by Cox regression hazards model, after that, nomogram was established to predict the 1-, 3-, and 5-year survival rates, which may help oncologists to understand the highly malignant tumor.

Androgenic alopecia (AGA) has a high incidence. Excess dihydrotestosterone in blood capillaries, which is converted from testosterone by 5α-reductase, is an AGA causative factor. We identified the inhibitory activity of four Polygonum multiflorum compounds against 5α-reductase via high-performance liquid chromatography, and the results showed that Physcion was a potent 5α-reductase inhibitor. Additionally, we found that through inhibiting 5α-reductase expression, Physcion could shorten the time of dorsal skin darkening and hair growth, improve hair follicle morphology, and significantly increase hair follicle count. Eventually, through molecular docking study, we found the binding energy and molecular interactions between Physcion and 5α-reductase type II. These results suggested that Physcion is a potent 5α-reductase inhibitor, as well as a new natural medicine for treating AGA.

Coronaviruses (CoVs) are nonsegmented, single-stranded, positive-sense RNA viruses highly pathogenic to humans. Some CoVs are known to cause respiratory and intestinal diseases, posing a threat to the global public health. Against this backdrop, it is of critical importance to develop safe and effective vaccines against these CoVs. This review discusses human vaccine candidates in any stage of development and explores the viral characteristics, molecular epidemiology, and immunology associated with CoV vaccine development. At present, there are many obstacles and challenges to vaccine research and development, including the lack of knowledge about virus transmission, pathogenesis, and immune response, absence of the most appropriate animal models.

Dengue fever is a major worldwide public health problem that, as estimated by the WHO, causes epidemics in over 100 countries, resulting in hundreds of millions of dengue virus (DENV) infections every year. In China, dengue fever mainly occurs in coastal areas. Recurring dengue outbreaks were reported by Guangdong Province almost every year since the first epidemic in 1978. DENV infections persisted in Guangzhou in consecutive years since 2000, with the dengue epidemic reaching a historical peak in 2014. Because Guangzhou is one of the largest cities for opening up in China, understanding the epidemiological characteristics of dengue fever in the city can hopefully provide a significant basis for developing effective dengue prevention strategies. In this study, a total of 34 DENV strains, including 29 DENV-1 strains and 5 DENV-2 strains, were isolated from a blood samples drawn from patients who were diagnosed with dengue fever by hospitals in Guangzhou during 2018. To explore the epidemiological characteristics of dengue fever, the envelope (E) gene obtained from the isolates was amplified for phylogenetic analysis. The results from the phylogenetic analysis showed that DENV in Guangzhou was mainly imported from Southeast Asian countries. Additionally, propagation paths based on phylogeographical analysis suggested potential local dengue transmission in Guangzhou.

The search for novel anti-hepatocellular carcinoma (HCC) agents is important. Mammalian target of rapamycin (mTOR) hyper-activation plays a pivotal role in promoting HCC tumorigenesis and chemoresistance. The current preclinical study evaluated the potential anti-HCC activity by a potent mTOR kinase inhibitor, WAY-600. We showed that WAY-600 inhibited survival and proliferation of HCC cell lines (HepG2 and Huh7) and primary human HCC cells. Caspase-dependent apoptosis was activated by WAY-600 in above HCC cells. Reversely, caspase inhibitors largely attenuated WAY-600's lethality against HCC cells. At the signaling level, WAY-600 blocked mTOR complex 1/2 (mTORC1/2) assemble and activation, yet activated MEK-ERK pathway in HCC cells. MEK-ERK inhibitors, PD-98059 and MEK-162, or MEK1/2 shRNA significantly potentiated WAY-600's cytotoxicity in HCC cells. Further studies showed that WAY-600 intraperitoneal (i.p.) administration in nude mice inhibited p-AKT Ser-473 and displayed significant anti-cancer activity against HepG2 xenografts. Remarkably, co-administration of MEK-162 further potentiated WAY-600's anti-HCC activity in vivo. These preclinical results demonstrate the potent anti-HCC activity by WAY-600, either alone or with MEK-ERK inhibitors.

Background: The treatment options for intractable metastatic colorectal cancer include regorafenib, trifluridine/tipiracil, and fruquintinib. In this study, we aimed to conduct a network meta-analysis for comparing the efficacy of these agents. Methods: We searched the PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrials databases for relevant literature, up to February 2020. The data were collected from randomized controlled trials on regorafenib, trifluridine/tipiracil, or fruquintinib, administered to patients with metastatic colorectal cancer who failed on treatment with oxaliplatin, irinotecan, or fluoropyrimidine. The primary end points, namely, the overall survival and progression-free survival, were analyzed for subsequent network analysis using the Review Manager and Aggregate Data Drug Information System software for performing direct and indirect comparisons. Results: A total of 7 trials were analyzed in this study. Trifluridine/tipiracil and regorafenib proved to be superior to the placebo, with respect to the overall survival (odds ratio: 0.38, 95% confidence interval: 0.27-0.52 for trifluridine/tipiracil; odds ratio: 0.47, 95% confidence interval: 0.26-0.84 for regorafenib) and progression-free survival (odds ratio: 0.18, 95% confidence interval: 0.05-0.67 for trifluridine/tipiracil; odds ratio: 0.06, 95% confidence interval: 0.04-0.09 for regorafenib). Regorafenib (80 mg) was superior to the placebo in terms of the overall survival and progression-free survival and inferior to trifluridine/tipiracil and fruquintinib. Network analysis revealed that the efficacy of trifluridine/tipiracil and fruquintinib was fundamentally similar, and both the agents were superior to regorafenib. Conclusion: Regorafenib (80 mg) was superior to the placebo, but inferior to 160 mg regorafenib, trifluridine/tipiracil, and fruquintinib. This study further revealed that the efficiency of trifluridine/tipiracil and fruquintinib is identical, but their toxicity profiles are different.

Radiofrequency ablation (RFA) is a minimally invasive technology for the treatment of liver malignancies and is used as an adjuvant therapy in patients with colorectal liver metastasis (CLM). This study enrolled a total of 49 CLM patients who underwent RFA treatment. Univariate and multivariate analyses were performed using the log-rank test and Cox proportional hazard model, respectively. Univariate analysis showed that OS was closely correlated with tumor size, frequency of RFA treatment, resection of the liver lesion, and CEA levels before RFA (p p