LDLR dysfunction induces LDL accumulation and promotes pulmonary fibrosis

Treatments for pulmonary fibrosis (PF) are ineffective because its molecular pathogenesis and therapeutic targets are unclear. Here, we show that the expression of low-density lipoprotein receptor (LDLR) was significantly decreased in alveolar type II (ATII) and fibroblast cells, whereas it was increased in endothelial cells from systemic sclerosis-related PF (SSc-PF) patients and idiopathic PF (IPF) patients compared with healthy controls. However, the plasma levels of low-density lipoprotein (LDL) increased in SSc-PF and IPF patients. The disrupted LDL-LDLR metabolism was also observed in four mouse PF models. Upon bleomycin (BLM) treatment, Ldlr-deficient (Ldlr-/-) mice exhibited remarkably higher LDL levels, abundant apoptosis, increased fibroblast-like endothelial and ATII cells and significantly earlier and more severe fibrotic response compared to wild-type mice. In vitro experiments revealed that apoptosis and TGF-β1 production were induced by LDL, while fibroblast-like cell accumulation and ET-1 expression were induced by LDLR knockdown. Treatment of fibroblasts with LDL or culture medium derived from LDL-pretreated endothelial or epithelial cells led to obvious fibrotic responses in vitro. Similar results were observed after LDLR knockdown operation. These results suggest that disturbed LDL-LDLR metabolism contributes in various ways to the malfunction of endothelial and epithelial cells, and fibroblasts during pulmonary fibrogenesis. In addition, pharmacological restoration of LDLR levels by using a combination of atorvastatin and alirocumab inhibited BLM-induced LDL elevation, apoptosis, fibroblast-like cell accumulation and mitigated PF in mice. Therefore, LDL-LDLR may serve as an important mediator in PF, and LDLR enhancing strategies may have beneficial effects on PF.

Criticality analysis for safety-critical software in nuclear power plant distributed control system

Software criticality analysis examines the degree of contribution that each individual failure mode of a software component has on the reliability of software. Higher safety integrity levels are assigned to software modules whose failures cause an unacceptable impact on the operation of the system, and these levels require the implementation of more rigorous software quality assurance measures as defined in IEEE Std 1012 and in the customer’s system requirements specification. In this paper, a novel software criticality analysis method is proposed, the results of which can be used to guide the development of newly developed software and the procurement of Commercial-Off-The-Shelf (COTS) software. The software structure is first analyzed and the software is divided into modules according to their functions. Then the criticality levels of software components are preliminarily classified by means of a safety criticality preliminary analysis tree, followed by their verification through the software hazard and operability analysis (HAZOP). Finally, the target Safety Integrity Level (SIL) of each software module is determined based on its criticality level and the overall safety objective (i. e., SIL) of the system it resides in. As an example, this proposed method is applied to a nuclear power plant safety-critical system to demonstrate the detail application process and to verify the feasibility of the method. Compared with the existing software criticality analysis methods, this method has better operability and verifiability, and can be utilized as a technical guidance for the software criticality analysis of nuclear power plant digital control systems.

Relationship between onset of eclampsia and AGTR1 gene polymorphisms

OBJECTIVE

We aimed to study the correlations of angiotensin II receptor type 1 (AGTR1) gene polymorphisms with the occurrence and development of eclampsia.

PATIENTS AND METHODS

A total of 200 pregnant women with eclampsia admitted to our hospital from January 1, 2017 to September 30, 2019 were collected as observation group and 200 normal pregnant women during the same period were recruited in the control group. Genome sequencing was performed to detect the AGTR1 gene polymorphisms in the two groups. Expression level of AGTR1 in both groups was detected. The influences of AGTR1 on clinical data of pregnant women with eclampsia were analyzed.

RESULTS

There were no significant differences in age (p=0.545), height (p=0.738), weight (p=0.695) and hypertension (p=0.372) between observation group and control group. However, significant differences were found in the distributions of alleles at AGTR1 rs1799870 (p=0.002) and AGTR1 rs52936049 (p=0.047) between groups. The frequencies of T allele at rs1799870 and rs52936044 in observation group were higher than those in the control group. In addition, the distributions of AGTR1 gene genotypes at rs1799870 (p=0.012), rs144520513 (p=0.008) and rs529360494 (p p =0.036) in observation group differed from those in control group. Observation group had higher frequencies of TT genotype at rs1799870, GG genotype at rs144520513 and TG genotype at rs529360494 than those in control group. Besides, the frequency of CGG haplotype (p=0.008) of AGTR1 gene in observation group was notably lower than that in the control group, while the frequency of TGT haplotype (p=0.012) of AGTR1 gene in the former was remarkably higher than that in the latter. Moreover, the linkage disequilibrium between rs529360494 and rs144520513 of AGTR1 gene was relatively high (D'=0.623). AGTR1 gene polymorphism rs529360494 showed an evident relationship with the expression of AGTR1 gene, and the expression of AGTR1 in pregnant women with eclampsia who carried TG genotype was markedly reduced (p<0.05). Furthermore, AGTR1 gene polymorphism rs1799870 was associated with prothrombin time (PT) in pregnant women with eclampsia (p=0.046), and PT in those carrying genotype TC was shorter. Rs144520513 was related to the levels of triglyceride (TG) (p<0.001) and low-density lipoprotein (LDL) (p<0.001) in pregnant women with eclampsia, and TG and LDL levels were significantly lower.

CONCLUSIONS

AGTR1 gene polymorphisms are closely associated with the onset and progression of eclampsia.

Thermally-assisted milling and hydrogenolysis for synthesizing ultrafine MgH2with destabilized thermodynamics

A novel process has been developed to synthesize MgH₂nanoparticles by combining ball milling and thermal hydrogenolysis of di-n-butylmagnesium (C₄H₉)₂Mg, denoted as MgBu₂. With the aid of mechanical impact, the hydrogenolysis temperature of MgBu₂in heptane and cyclohexane solution was considerably lowered down to 100 °C, and the MgH₂nanoparticles with an average particle size ofca.8.9 nm were obtained without scaffolds. The nano-size effect of the MgH₂nanoparticles causes a notable decrease in the onset dehydrogenation temperature of 225 °C and enthalpy of 69.78 kJ mol^-1 · H₂. This thermally-assisted milling and hydrogenolysis process may also be extended for synthesizing other nanomaterials.

[Chaihu Guizhi decoction produces antidepressant-like effects via sirt1-p53 signaling pathway]

OBJECTIVE

To investigate the mechanism of the antidepressant-like effects of Chaihu Guizhi decoction (CGD).

OBJECTIVE

Chaihu Guizhi decoction at the daily dose of 17 g/kg and solvent vehicle were administered by gavage in 12 and 14 male C57BL/6J mice for 7 consecutive days, respectively. Forced swimming test (FST), elevated plus maze (EPM) test, open field test (OFT) and novelty-suppressed feeding test (NSF) were performed to assess the depression- and anxiety-like behaviors and motor ability of the mice. We further used chronic social defeat stress (CSDS) and social interaction test to evaluate the antidepressant-like effects of CGD in comparison with the solvent vehicle. Western blotting and RT-qPCR were performed to detect the expressions of sirt1, p53, acetylated p53, and the neuron plasticity-related genes including synapsin I (Syn1), Rab4B, SNAP25 and tubulin beta4b in the hippocampus of the mice.

OBJECTIVE

In FST, the immobility time of CGDtreated mice was decreased significantly (P < 0.05); no significant differences were found in the performances in EPM, NSF and OFT tests between the two groups. In social interaction test, the mouse models of CSDS treated with CGD showed significantly increased time in the interaction zone (P < 0.05). Compared with those in the vehicle group, the CGD-treated mouse models exhibited significantly increased protein level of SIRT1 and decreased p53 acetylation (P < 0.05) with up-regulated synapsin I mRNA expression in the hippocampus (P < 0.05); no significant difference were found in Rab (P=0.813), SNAP (P=0.820), or Tubb mRNA expressions (P=0.864) between the two groups.

OBJECTIVE

CGD produces antidepressant-like effects in mice possibly through the sirt1-p53 signaling pathway and synaptic plasticity.

Pulsed Microfluid Force-Based On-Chip Modular Fabrication for Liver Lobule-Like 3D Cellular Models

In vitro three-dimensional (3D) cellular models with native tissue-like architectures and functions have potential as alternatives to human tissues in regenerative medicine and drug discovery. However, it is difficult to replicate liver constructs that mimic in vivo microenvironments using current approaches in tissue engineering because of the vessel-embedded 3D structure and complex cell distribution of the liver. This paper reports a pulsed microflow-based on-chip 3D assembly method to construct 3D liver lobule-like models that replicate the spatial structure and functions of the liver lobule. The heterogeneous cell-laden assembly units with hierarchical cell distribution are fabricated through multistep photopatterning of different cell-laden hydrogels. Through fluid force interaction by pulsed microflow, the hierarchical assembly units are driven to a stack, layer by layer, and thus spatially assemble into 3D cellular models in the closed liquid chamber of the assembly chip. The 3D models with liver lobule-like hexagonal morphology and radial cell distribution allow the dynamic perfusion culture to maintain high cell viability and functional expression during long-term culture in vitro. These results demonstrate that the fabricated 3D liver lobule-like models are promising for drug testing and the study of individual diagnoses and treatments.

High expression of LINC0163 promotes progression of papillary thyroid cancer by regulating epithelial-mesenchymal transition MITF

OBJECTIVE

The purpose of this study was to detect the expression of long non-coding ribonucleic acid 00163 (LINC00163) in human papillary thyroid cancer (PTC), and to observe the influence of downregulated LINC00163 on the proliferative and metastatic capacities of human PTC cells.

PATIENTS AND METHODS

Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) assay was applied to measure the expression level of LINC00163 in PTC tissues and para-carcinoma tissues, as well as that in normal human thyroid cells (Nthy-ori3-1) and PTC cells. After the expression of LINC00163 in PTC cells was interfered, qRT-PCR assay was performed to determine the interference efficiency, and colony formation and Cell Counting Kit-8 (CCK-8) assays were conducted to study the impacts of small interfering (si)-LINC00163 on the proliferative capacity of PTC cells. Moreover, wound healing and transwell assays were adopted to investigate the changes in the migratory and invasive abilities of PTC cells after the interference in the expression of LINC00163 in PTC cells. Finally, the changes in expressions of molecular markers in downstream signaling pathways after interference in LINC00163 expression were examined via Western blotting assay.

RESULTS

In 51 cases of PTC tissues and corresponding para-carcinoma tissues, 41 cases exhibited an up-regulated expression of LINC00163, and qRT-PCR results indicated that PTC cells also had an up-regulated expression of LINC00163 compared with normal human thyroid cells. After the expression of LINC00163 in PTC cells was interfered, the results of colony formation and CCK-8 assays manifested that the proliferative capacity of the cells declined. It was also shown in wound-healing and transwell assay results that the migratory and invasive abilities of the cells were weakened. In addition, the results of Western blotting assay revealed expression changes in the molecular markers of epithelial-mesenchymal transition (EMT).

CONCLUSIONS

The expression of LINC00163 in NSCLC tissues and cells is upregulated, and highly expressed LINC00163 can promote PTC cell proliferation and metastasis by regulating the EMT.

A triple-classification radiomics model for the differentiation of pleomorphic adenoma, Warthin tumour, and malignant salivary gland tumours on the basis of diffusion-weighted imaging

AIM

To develop and validate a triple-classification radiomics model for the preoperative differentiation of pleomorphic adenoma (PA), Warthin tumour (WT), and malignant salivary gland tumour (MSGT) based on diffusion-weighted imaging (DWI).

MATERIALS AND METHODS

Data from 217 patients with histopathologically confirmed salivary gland tumours (100 PAs, 68 WTs, and 49 MSGTs) from January 2015 to March 2019 were analysed retrospectively and divided into a training set (n=173), and a validation set (n=44). A total of 396 radiomic features were extracted from the DWI of all patients. Analysis of variance (ANOVA) and least absolute shrinkage and selection operator (LASSO) regression were used to select radiomic features, which were then constructed using three classification models, namely, logistic regression method (LR), support vector machine (SVM), and K-nearest neighbor (KNN). The diagnostic performance of the radiomics model was quantified by the receiver operating characteristic (ROC) curve and area under the ROC curve (AUC) of the training and validation data sets.

RESULTS

The 20 most valuable features were investigated based on the LASSO regression. LR and SVM methods exhibited better diagnostic ability than KNN for multiclass classification. LR and SVM had the best performance and yielded the AUC values of 0.857 and 0.824, respectively, in the training data set and the AUC values of 0.932 and 0.912, respectively, in the validation data set of MSGT diagnosis.

CONCLUSION

DWI-based triple-classification radiomics model has predictive value in distinguishing PA, WT, and MSGT, which can be used for preoperative auxiliary diagnosis in clinical practice.

3,5-Dimethoxy-4-hydroxy myricanol attenuated oxidative stress-induced toxicity on cardiomyoblast cells

Myocardial ischemia is the main reason for ischemic heart diseases. Antioxidant treatment is considered as a possible approach to prevent myocardial ischemia injury, because oxidative stress is a key factor triggering it. This study was to investigate the protective effects of 3,5-dimethoxy-4-hydroxy myricanol (DHM) against oxidative stress-induced cytotoxicity on H9c2 cells and further explore its mechanisms. The oxidative stress and inflammatory response markers were detected by H2DCFDA fluorescent measurement, enzyme-linked immunosorbent assay (ELISA), real-time PCR and Western blot. Results showed DHM exerted inhibitory effects against H9c2 cell damage. Furthermore, DHM decreased oxidative stress in H9c2 cells through up-regulating protein expression of heme oxygenase-1 (HO-1) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Moreover, DHM inhibited inflammatory responses through down-regulating the protein expression of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB). DHM exerted protective activities against oxidative stress-induced cell damage, at least through decreasing oxidative stress and inhibiting inflammatory responses, indicating that DHM have the potential to be developed as therapeutic agents for the treatment of myocardial ischemia.

EZH2-mediated H3K27me3 enrichment on the lncRNA MEG3 promoter regulates the growth and metastasis of glioma cells by regulating miR-21-3p

OBJECTIVE

Glioma is one of the most common and invasive brain tumors worldwide. Long non-coding RNAs (LncRNAs) play an important role in the development of glioma. However, the regulatory mechanism of LncRNAs in glioma has not been fully elucidated. This study aimed to explore the interaction of lncRNA maternally expressed gene 3 (MEG3) and aberrant histone modification in glioma.

MATERIALS AND METHODS

The expression levels of MEG3 and miR-21-3p in glioma cells were measured by quantitative polymerase chain reaction (qPCR). EZH2 (enhancer of zeste homolog 2) and H3K27me3 expression in glioma cells were detected by Western Blot (WB). The binding site of the promoter of MEG3 by H3K27me3 was confirmed by ChIP-Real-time PCR. The direct target of MEG3 and miR-21-3p in glioma cells was measured by a luciferase reporter assay. Cell proliferation was detected by Cell Counting Kit-8 (CCK8), and cell invasion and migration were measured by Transwell assays.

RESULTS

EZH2 and miR-21-3p were upregulated and MEG3 was downregulated in glioma cells. Silencing of EZH2 inhibited cell proliferation, migration, and invasion in U87 and U251 cells. Meanwhile, the expression of H3K27me3 could be significantly inhibited by EZH2 interference. H3K27me3 protein can bind to MEG3 promoter directly. EZH2 inhibition and MEG3 down-expression in U87 cells reversed the effects of silencing of EZH2 on glioma cell growth and metastasis. However, EZH2 inhibition and MEG3 overexpression in U251 cells restricted cell proliferation, migration, and invasion. Furthermore, miR-21-3p was verified to interact with MEG3 by direct binding. Inhibition of MEG3 promoted U87 cell growth and metastasis, which was further strengthened following the co-transfection of si-MEG3 and miR-21-3p. Overexpressed MEG3 inhibited U251 cell growth and metastasis and a complete reversal of the results observed in the co-transfection of LV-MEG3 and miR-21-3p.

CONCLUSIONS

EZH2 was highly expressed in glioma cells and EZH2-mediated H3K27me3 enrichment on the MEG3 promoter regulated the growth and metastasis of glioma cells by targeting miR-21-3p. It potentially provided a new therapeutic marker targeting glioma.