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Objective To investigate the effects of interleukin-33(IL-33)on HaCAT cells and psoriasis-like inflammation induced by imiquimod(IMQ) in mice. Methods Twenty-four hours after HaCAT cells were plated, the cell proliferation and autophagy-related protein were detect by CCK8 and Western blot. A psoriasis-like lesion model was established in mouse. Thirty female BALB/c mice of clean grade were randomly divided into three groups: control group, IMQ group, and IL-33 treatment group. After 6 days of continuous treatment, the lesions on the back of the mouse were observed. Results The treatment of IL-33 could enhance the proliferation of HaCAT cells and promote the expression of LC3, Beclin1 and p-STAT3 proteins. In the mouse psoriasis-like model, the thickened ear skin, scaly erythema and erythematous lesions on the back were seen and thickening of the epidermis, epidermal extension with parakeratosis were shown. These phenomena were more obvious in IL-33 treatment group(P＜0.05). The expression of autophagy-related proteins in the skin lesions of the IL-33 treatment group was significantly decreased compared with the control group and IMQ group(P＜0.05). Conclusions IL-33 promotes the proliferation of HaCAT cells, induces autophagy, and aggravates the occurrence and development of psoriatic lesions induced by imiquimod in mice, which may be involved in the activation of the STAT3 signaling pathway.

Influenza A virus (IAV) hijacks the endocytosis of host cells in the early stages of infection. It is known that microfilaments and microtubules play a vital role in viral infections. However, the potential involvement of intermediate filaments (IFs) and their mechanism in IAV infection are unclear. In this study, we combined quantum dot-based single-virus tracking (QSVT) with conventional biological methods to quantitatively analyze the effects of vimentin IFs on the early stages of IAV infection. The results showed that the knockdown of vimentin did not affect the internalization and motion dynamics of IAV but impacted the transport of IAV to late endosomes. Statistical analysis revealed that the knockdown of vimentin caused more than 20% IAV to remain in the early endosomes after rapid movement than in normal cells and reduced the efficiency of subsequent membrane fusion and genome release. These results suggested that vimentin facilitates IAV infection by participating in the maturation of endosomes. Our study expands the understanding of the mechanism of endocytosis of IAV and fills the gap in the knowledge on vimentin IFs. [ABSTRACT FROM AUTHOR]

ABSTRACT Composites of Poly(2,3-dimethylaniline) and inorganic Na+-montmorillonite clay were synthesized by emulsion polymerization. The as-synthesized composites (PDMA) were characterized by Fourier Transform Infrared Spectroscopy, X-ray diffraction, and scanning electron microscopy. The protective performance against corrosion of the samples was evaluated by Tafel and electrochemical impedance spectroscopy measurements. The results showed that the composite containing 5 wt. % of clay loading (PDMA-5%) displayed a better anticorrosive performance than other samples. The Epoxy(E) blend with PDMA-5% (EPM5) coating was founded to have a higher corrosion potential and a lower current density than that of Epoxy blend P(2,3-DMA) (EP) coating. The impedance value of EPM5 coating was about 6.68×106Ω·cm2 in 5 wt. % NaCl solution even after 288 h, compared to EP (4.26×105Ω·cm2) coating, which went to show that the corrosion inhibition of P(2,3-DMA) could be effectively enhanced by incorporating MMT into the P(2,3-DMA) matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4528-4533, 2013 [ABSTRACT FROM AUTHOR]

Viral diseases are among the main threats to public health. Understanding the factors affecting viral invasion is important for antiviral research. Until now, it was known that most viruses have very low plaque-forming unit (PFU)-to-particle ratios. However, further investigation is required to determine the underlying factors. Here, using quantitative single-particle analysis methods, the invasion of Semliki Forest virus (SFV), Japanese encephalitis virus (JEV), and influenza A virus (IAV) containing attachment to the cell surface, entry into the cell, transport towards the cell interior, and fusion with endosomes to release nucleocapsids were quantitatively analysed in parallel. It was found that for SFV with an PFU-to-particle ratio of approximately 1:2, an entry efficiency of approximately 31% limited infection. For JEV, whose PFU-to-particle ratio was approximately 1:310, an attachment efficiency of approximately 27% and an entry efficiency of 10% were the main factors limiting its infection. Meanwhile, for IAV with PFU-to-particle ratios of 1:8100, 5% attachment efficiency, 9% entry efficiency, and 53% fusion efficiency significantly limited its infection. These results suggest that viruses with different infectivities have different limited steps in the invasion process. Moreover, there are significant differences in attachment efficiencies among viruses, emphasizing the pivotal role of attachment in viral invasion. The influence of the virus purification method on virus invasion was also investigated. This study, for the first time, reports the efficiencies of different stages of virus invasion, leading to a better understanding of virus invasion and providing a protocol to quantitatively analyse the virus invasion efficiency.

Endostatin (ES, ENDO) has been reported to suppress the growth of tumors while inducing the proliferation of lung cancer stem cells (LCSCs), causing a poor prognosis for lung cancer. In this study, we aimed to clarify whether BRM270 can inhibit the proliferation of cancer stem cells (CSCs). Endostatin + BRM270 showed anti-tumor effects by reducing tumor volume and increasing survival. Administration of BRM270 reduced the number of aldehyde dehydrogenase-positive (ALDH+) cells and the level of ALDH1A1 expression in tumors by increasing the level of miR-128 while decreasing the levels of BMI-1, ABCC-5, E2F3, and c-MET. The luciferase activity of miR-128 promoter was increased by an increasing concentration of BRM270. In addition, BMI-1, ABCC-5, E2F3, and c-MET were identified as candidate targets of miR-128, and the overexpression of miR-128 significantly reduced mRNA/protein levels of BMI-1, ABCC-5, E2F3, and c-MET in A549 and H460 cells. Administration of BRM270 inhibited the expression of BMI-1, ABCC-5, E2F3, and c-MET in a dose-dependent manner. In this study, we showed for the first time that the combined administration of endostatin and BRM270 achieved anti-tumor effects while suppressing the proliferation of stem cells., Competing Interests: The authors declare no competing interests., (© 2021 The Authors.)

Influenza A virus (IAV) is internalized into its host cells by endocytosis, which involves many cellular proteins and molecules. In this study, we focus on the function of calcium ion (Ca 2+ ) in IAV endocytosis. We have found that IAV infection is accompanied by the increase in concentration of cytosolic Ca 2+ , which is mainly attributed to the influx of extracellular Ca 2+ . When Ca 2+ influx is abolished, IAV internalization will be markedly suppressed, but the virus attachment to its host cells will be unaffected. Extracellular Ca 2+ influx is essential to the clathrin-mediated endocytosis (CME) of IAVs but dispensable to the clathrin-independent endocytosis of the virus and is dispensable to the CME of transferrin or low-density lipoprotein as a control. Ca 2+ influx might participate in the dynamin-promoted membrane fission in the CME of IAVs. Our study highlights that IAVs enter host cells via extracellular Ca 2+ influx-involved clathrin- and dynamin-dependent endocytosis, which will facilitate better understanding of IAV infection and development of anti-influenza drugs.

Objective To observe the effects of Hedyotis diffusa extract (HDE) on the prolifera- tion, apoptosis, and inflammatory factors of HaCaT cells, and to explore its possible molecular mecha- nisms. Methods HaCaT cells were divided into 3 groups, the vehicle group, the control group, and 3 dose HDE groups. No epidermal growth factor (EGF) or HDE was added in the vehicle group. EGF was added with no HDE treatment in the control group. HDE (25, 50, 100 mg/mL) and EGF were added in the 3 HDE groups to co-culture HaCaT cells. The effects of HDE on EGF-induced proliferation of HaCaT cells were de- tected using CCK-8 assay. The effects of HDE on the growth cycle and apoptosis rate of HaCaT cells were measured using flow cytometry. Moreover, protein expression levels of Ki67, Bcl-xL, clAP1 , procaspase- 3, and cleaved caspase-3 were determined using Western blot. In addition, levels of IL-6, IL-8, and IL-10 in the supernatant were detected using ELISA. The level of phosphoration of NF-κB p65 (p-p65) was meas- ured using Western blot. Results Compared with the vehicle group, the absorbance of HaCaT cells and the expression level of Ki67 increased (P <0. 05, P <0. 01) ; levels of p-p65, IL-6, and IL-8 were elevated (P <0. 05, P <0. 01); IL-10 level was lowered (P <0.01) in the control group. Compared with the control group, the absorbance of HaCaT cells and the expression level of Ki67 decreased (P <0.05, P <0.01) ; levels of p-p65, IL-6, and IL-8 were reduced (P <0. 05, P <0. 01); IL-10 level was elevated (P <0. 05, P < 0.01) in the 3 dose HDE groups. Meanwhile, the apoptosis rate of HaCaT cells increased more in the 3 dose HDE groups than in the control group (P <0. 05, P <0. 01). The percentage of HaCaT cells at G1 phase was 58. 51 %, 73.12%, and 79. 95% in 25, 50, and 100 mg/mL HDE groups, respectively, showing statisti- cal difference when compared with that in the control group (52. 85%; P <0. 05, P <0. 01). The percentage and apoptosis rate of HaCaT cells at G1 phase were elevated more in 50 and 100 mg/mL HDE groups than in 25 mg/mL HDE group (P <0. 01). Besides, the percentage and apoptosis rate of HaCaT cells at G1 phase were elevated more in 100 mg/mL HDE group than in 50 mg/mL HDE group (P <0. 05). Compared with the control group, protein expression levels of Bcl-xL and cIAP1 were reduced in 100 mg/mL HDE group (P < 0. 01). There was no statistical difference in caspase-3 total amount (P >0. 05), but cleaved caspase-3 ex- pression increased with statistical difference (P <0. 01). Conclusion HDE inhibited the proliferation of HaCaT cells possibly by arresting HaCaT cell growth at G1 phase, promoted the apoptosis of HaCaT cells by stressing protein expressions of Bcl-xL and cIAPI , and elevating protein expressions of cleaved caspase-3, and suppressed inflammatory response of HaCaT cells via regulating NF-κB expression.

The aim of the present study was to characterize and quantify the numbers and expression levels of cells markers associated with dendritic cell (DC) maturation in small airways in current smokers and non-smokers with or without chronic obstructive pulmonary disease (COPD). Lung tissues from the following 32 patients were obtained during resection for lung cancer: Eight smokers with COPD, eight non-smokers with COPD, eight current smokers without COPD and eight non-smokers without COPD, serving as a control. The tissue sections were immunostained for cluster of differentiation (CD)83+ and CD1a+ to delineate mature and immature DCs, and chemokine receptor type 7 (CCR7+) to detect DC migratory ability. Myeloid DCs were collected from the lung tissues, and subsequently the CD83+ and CCR7+ expression levels in the lung myeloid DCs were detected using flow cytometry. The expression levels of CD83+, CD1a+ and CCR7+ mRNA in total lung RNA were evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Evident chronic bronchitis and emphysema pathological changes were observed in the lung tissues of patients with COPD. The results revealed that the numbers of CD83+ and CCR7+ DCs were reduced but the numbers of CD1a+ DCs were significantly increased in the COPD group as compared with the control group (P<0.05, respectively). Using RT-qPCR, the expression levels of CCR7+ and CD83+ mRNA were found to be reduced in the smokers with COPD as compared with the non-smokers without COPD group (P<0.05, respectively). Excessive local adaptive immune responses are key elements in the pathogenesis of COPD. Cigarette smoke may stimulate immune responses by impairing the homing of airway DCs to the lymph nodes and reduce the migratory potential of DCs. The present study revealed that COPD is associated with reduced numbers of mature CD83+ DCs and lower CCR7+ expression levels in small airways.

Objective: To evaluate the siRNA-mediated inhibitory effect of nuclear factor-kappaB (NF-kappaB) p65 on expression of p65, and explore the effect of blockade of NF-kappaB signal pathway on cell apoptosis in cutaneous squamous cell carcinoma (cutaneous SCC)., Methods: Cutaneous SCC cell line SCL-1 cells were transfected with 50 nmol/L p65 siRNA. The expression level of p65 mRNA was measured using RT-PCR method at 0, 24, 48 and 72 h . Expressions of p65, bcl-2 and bax proteins were determined using Western blotting. Activities of caspase-3/9 was detected by Caspase-Glo®-3/7, 8 and 9 kit. Finally, cell apoptosis was detected using flow cytometry., Results: The expression level of p65 mRNA in Cutaneous SCC SCL-1 cells was obviously down-regulated 48 h after transfection with p65 siRNA, and a significant difference was detected, as compared with 0 h after (0.23 ± 0.10 vs. 0.66 ± 0.05, P<0.05). The protein levels of p65 and bcl-2 decreased, and the bax protein level and activities of caspase-3/9 increased after transfection with p65 siRNA at h 48 . Further, the results of flow cytometry demonstrated that p65 siRNA could induce apoptosis of SCL-1 cells, and cell apoptosis ratio (20.28% ± 1.87%) in p65 siRNA group was significantly higher than that in the untreated group and control siRNA group (9.13% ± 1.51% and 9.37% ± 1.38%, respectively, F=47.532, P<0.01)., Conclusion: p65 siRNA can block NF-kappaB signal pathway, down-regulate expression of bcl-2, elevate the bax level and increase the activities of caspase-3/9, suggesting that NF-kappaB signal pathway may be a key molecular target for therapy of cutaneous SCC.