The complementary contribution of each order topology into the synchronization of multi-order networks.

Higher-order interactions improve our capability to model real-world complex systems ranging from physics and neuroscience to economics and social sciences. There is great interest nowadays in understanding the contribution of higher-order terms to the collective behavior of the network. In this work, we investigate the stability of complete synchronization of complex networks with higher-order structures. We demonstrate that the synchronization level of a network composed of nodes interacting simultaneously via multiple orders is maintained regardless of the intensity of coupling strength across different orders. We articulate that lower-order and higher-order topologies work together complementarily to provide the optimal stable configuration, challenging previous conclusions that higher-order interactions promote the stability of synchronization. Furthermore, we find that simply adding higher-order interactions based on existing connections, as in simple complexes, does not have a significant impact on synchronization. The universal applicability of our work lies in the comprehensive analysis of different network topologies, including hypergraphs and simplicial complexes, and the utilization of appropriate rescaling to assess the impact of higher-order interactions on synchronization stability.

Mutational and Transcriptional Characterization Establishes Prognostic Models for Resectable Lung Squamous Cell Carcinoma.

Background: The prognosis of non-small cell lung cancer (NSCLC) patients has been comprehensively studied. However, the prognosis of resectable (stage I-IIIA) lung squamous cell carcinoma (LUSC) has not been thoroughly investigated at genomic and transcriptional levels. Methods: Data of genomic alterations and transcriptional-level changes of 355 stage I-IIIA LUSC patients were downloaded from The Cancer Genome Atlas (TCGA) database, together with the clinicopathological information (training cohort). A validation cohort of 91 patients was retrospectively recruited. Data were analyzed and figures were plotted using the R software. Results: Training cohort was established with 355 patients. TP53 (78%), TTN (68%), CSMD3 (39%), MUT16 (36%) and RYR2 (36%) were genes with the highest mutational frequency. BRINP3, COL11A1, GRIN2B, MUC5B, NLRP3 and TENM3 exhibited significant higher mutational frequency in stage III (P < 0.05). Patients with stage III also exhibited significantly higher tumor mutational burden (TMB) than those with stage I (P < 0.01). The mutational status of 10 genes were found to have significant stratification on patient prognosis. TMB at threshold of 25 percentile (TMB = 2.39 muts/Mb) also significantly stratified the patient prognosis (P = 0.0003). Univariate and multivariate analyses revealed TTN, ADGRB3, MYH7 and MYH15 mutational status and TMB as independent risk factors. Further analysis of transcriptional profile revealed many significantly up- and down-regulated genes, and multivariate analysis found the transcriptional levels of seven genes as independent risk factors. Significant factors from the multivariate analyses were used to establish a Nomogram model to quantify the risk in prognosis of individual LUSC patients. The model was validated with a cohort containing 91 patients, which showed good predicting efficacy and consistency. Conclusion: The influencing factors of prognosis of stage I-III LUSC patients have been revealed. Risk factors including gender, T stage, cancer location, and the mutational and transcriptional status of several genes were used to establish a Nomogram model to assess the patient prognosis. Subsequent validation proved its effectiveness.

First-line crizotinib therapy is effective for a novel SEC31A-anaplastic lymphoma kinase fusion in a patient with stage IV lung adenocarcinoma: a case report and literature reviews.

Anaplastic lymphoma kinase (ALK) fusion was found in 3-7% of all patients with nonsmall cell lung cancer. The efficacy of ALK-tyrosine kinase inhibitor (ALK-TKI) in EML4-ALK has been extensively studied, whereas little evidence is available on its efficacy in rare ALK fusions. Here, we report the performance of crizotinib in a 50-year-old male lung adenocarcinoma patient with a novel rare SEC31A-ALK fusion. Computed tomography (CT) scan revealed multiple patchy high-density shadows in both lungs. The larger ones are located near the spine in the right lung lower lobe (55 × 34 mm) and the left hilar region (45 × 26 mm), with multiple enlarged mediastinal and axillary lymph nodes. Biopsy by bronchoscopy revealed invasive adenocarcinoma. The pathological stage of T4N3M1b (clinical stage: IVA) was confirmed. Next-generation sequencing revealed SEC31A: exon20~ALK: exon20 fusion, ABCB1 amplification, FGF19 amplification, DAXX p.S213L, MUTYH p.R19*(germline mutation and pathogenic) with tumor mutational burden at 3.2 mutations/Mb, microsatellite stable, proficient mismatch repair and PD-L1 positive [immunohistochemistry, tumor proportion score(TPS) 1-49% (TPS = 25%)]. Based on these findings, crizotinib was recommended for the first-line treatment at 250 mg twice daily. The first CT assessment after 2-month therapy showed partial response (PR) for the two larger lesions, multiple shadows and nodules in both lungs and the mediastinal and axillary lymph nodes. Crizotinib at 250 mg twice a day was applied in the following 9 months. Assessment at every 3 months (up to 1-year after diagnosis) showed further absorption for all lesions (continuous PR). We reported a novel rare ALK fusion SEC31A: EXON20~ALK: exon20 and showed the effectiveness of crizotinib against the fusion. This study provided strong evidence for the efficacy of ALK-TKI for rare ALK fusion.

Reservoir computing with higher-order interactive coupled pendulums.

The reservoir computing approach utilizes a time series of measurements as input to a high-dimensional dynamical system known as a reservoir. However, the approach relies on sampling a random matrix to define its underlying reservoir layer, which leads to numerous hyperparameters that need to be optimized. Here, we propose a nonlocally coupled pendulum model with higher-order interactions as a novel reservoir, which requires no random underlying matrices and fewer hyperparameters. We use Bayesian optimization to explore the hyperparameter space within a minimal number of iterations and train the coupled pendulums model to reproduce the chaotic attractors, which simplifies complicated hyperparameter optimization. We illustrate the effectiveness of our technique with the Lorenz system and the Hindmarsh-Rose neuronal model, and we calculate the Pearson correlation coefficients between time series and the Hausdorff metrics in the phase space. We demonstrate the contribution of higher-order interactions by analyzing the interaction between different reservoir configurations and prediction performance, as well as computations of the largest Lyapunov exponents. The chimera state is found as the most effective dynamical regime for prediction. The findings, where we present a new reservoir structure, offer potential applications in the design of high-performance modeling of dynamics in physical systems.

Identification of tumor-suppressor genes in lung squamous cell carcinoma through integrated bioinformatics analyses.

Lung cancer is a prevalent malignancy, and fatalities of the disease exceed 400,000 cases worldwide. Lung squamous cell carcinoma (LUSC) has been recognized as the most common pathological form of lung cancer. The comprehensive understanding of molecular features related to LUSC progression has great significance in LUSC prognosis assessment and clinical management. In this study, we aim to identify a panel of signature genes closely associated with LUSC, which can provide novel insights into the progression of LUSC. Gene expression profiles were retrieved from public resources including gene expression omnibus (GEO) and the cancer genome atlas (TCGA) database. Differentially expressed genes (DEGs) between LUSC specimens and normal lung tissues were identified by bioinformatics analyses. A total of 66 DEGs were identified based on two cohorts of data. CytoHubba plugin of Cytoscape software was utilized for the further analyses of the top 10 candidate hub genes including OGN, ABI3BP, MAMDC2, FGF7, FAM107A, SPARCL1, DCN, COL14A1, and MFAP4 and CHRDL1, which showed significant downregulation in LUSC. Two LUSC cell lines were used to validate the functions of CHRDL1 and FAM107A through overexpression experiment. Together, our data revealed novel candidate tumor-suppressor genes in LUSC, suggesting previously unappreciated mechanisms in the progression of LUSC.

Shapiro steps and chaos in the Frenkel-Kontorova model with substrate lateral vibration.

Numerical simulations are used to examine the dynamics of the dc-driven Frenkel-Kontorova model with an oscillation substrate subjected to lateral periodic excitations in overdamped and underdamped cases, respectively. The results reveal that the system exhibits frequency locking and chaotic behaviors due to the fact that the lateral vibration of the substrate potential introduces an additional frequency and degree of freedom into the system. In the overdamped case, we show that the appearance of subharmonic Shapiro steps can be attributed to the deformation of the substrate potential or inertia. The characteristics of the steps are significantly affected by the amplitude and frequency of the lateral vibration. When the vibration frequency is relatively high, the change of the width of the first harmonic Shapiro step with increasing amplitude exhibits a Bessel-type oscillation, but the oscillation deviates from the Bessel curve at lower frequencies. In the amplitude dependence, although the oscillatory behavior of the critical depinning force at the high frequency is anomalous, local maxima (minima) of the first step width correspond to local minima (maxima) of the critical depinning force, and the largest Lyapunov exponent obtained in the pinned state represents a mirror relationship of the critical depinning force. In contrast to the overdamped system, the underdamped one exhibits both subharmonic Shapiro steps and chaotic behaviors. We show the increased inertia of the latter system plays an important role in suppressing the emergence of subharmonic steps, which is opposite to the result of the former. When the dc force changes, chaos appears not only between adjacent subharmonic Shapiro steps but also on some specific steps where chaos should be avoided. The variation regularity of the first step width and the critical depinning force is thus annihilated in vibration amplitude and frequency dependence. However, superlubricity can be achieved by careful adjustment of vibration amplitude and frequency. The findings can serve as a theoretical guideline for technological applications such as device building and voltage standards.

Taming non-stationary chimera states in locally coupled oscillators.

The imperfect traveling chimera (ITC) state is a novel non-stationary chimera pattern in which the incoherent domain of oscillators spreads into the coherent domain. We investigate the ITC state in locally coupled pendulum oscillators with heterogeneous driving forces. We introduce the heterogeneous phase value in the driving forces by two different ways, namely, the random phase from uniform distribution and random phase directions with identical amplitude. We discover two transition mechanisms from ITC to coherent state through traveling chimera-like state by taking the two different phase heterogeneity. The transition phenomena are investigated using cylindrical and polar coordinate phase spaces. In the numerical study, we propose a quantitative measurement named "spatiotemporal consistency" strength for distinguishing the ITC from the traveling one. Our research facilitates the exploration of potential applications of heterogeneous interactions in neuroscience.

Identification of Novel Characteristics in TP53-Mutant Hepatocellular Carcinoma Using Bioinformatics.

Background: TP53 mutations are the most frequent mutations in hepatocellular carcinoma (HCC) and affect the occurrence and development of this cancer type. Therefore, it is essential to clarify the function and mechanism of TP53 mutations in HCC. Methods: We performed a sequence of bioinformatic analyses to elucidate the characteristics of TP53 mutations in HCC. We downloaded the data of hepatocellular carcinoma from The Cancer Genome Atlas database and used different R packages for serial analyses, including gene mutation analysis, copy number variation analysis, analysis of the tumor mutational burden and microsatellite instability, differential gene expression analysis, and functional enrichment analysis of TP53 mutations, and performed gene set enrichment analysis. We established a protein-protein interaction network using the STRING online database and used the Cytoscape software for network visualization, and hub gene screening. In addition, we performed anticancer drug sensitivity analysis using data from the Genomics of Drug Sensitivity in Cancer. Immune infiltration and prognosis analyses were also performed. Results: Missense mutations accounted for a great proportion of HCC mutations, the frequency of single nucleotide polymorphisms was high, and C > T was the most common form of single nucleotide variations. TP53 had a mutation rate of 30% and was the most commonly mutated gene in HCC. In the TP53 mutant group, the tumor mutational burden (p < 0.001), drug sensitivity (p < 0.05), ESTIMATE score (p = 0.038), and stromal score (p < 0.001) dramatically decreased. The Cytoscape software screened ten hub genes, including CT45A1, XAGE1B, CT55, GAGE2A, PASD1, MAGEA4, CTAG2, MAGEA10, MAGEC1, and SAGE1. The prognostic model showed a poor prognosis in the TP53 mutation group compared with that in the wild-type group (overall survival, p = 0.023). Univariate and multivariate cox regression analyses revealed that TP53 mutation was an independent risk factor for the prognosis of HCC patients (p <0.05). The constructed prognostic model had a favorable forecast value for the prognosis of HCC patients at 1 and 3 years (1-year AUC = 0.752, 3-years AUC = 0.702). Conclusion: This study further deepened our understanding of TP53-mutated HCC, provided new insights into a precise individualized therapy for HCC, and has particular significance for prognosis prediction.

Cholesterol crystals activate NLRP3 inflammasomes and promote gallstone formation by increasing mucin secretion.

Cholesterol crystals participate in cholesterol nucleation; however, the role of cholesterol crystals in gallstone development is unknown. Mucin secretion contributes to increased size of gallstones. Cholesterol crystals activate inflammasomes and participate in many sterile inflammation related human diseases. We investigated the role of cholesterol crystals and mucins in sterile inflammation and gallstone enlargement. We found that expression of mucin 5AC (MUC5AC), NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) and interleukin-1b (IL-1b) was increased significantly in tissues adjacent to gallstones. Experiments in vitro showed that cholesterol crystals promote MUC5AC secretion; they also increase expression of NLRP3, NLR family CARD domain-containing 4 (NLRC4), apoptosis-associated speck-like protein containing caspase recruitment domain (ASC), and cleaved caspase-1 in biliary epithelial cells. Inhibition of Inflammasomes by NLRP3, ASC or caspase-1 small interfering RNAs reduced MUC5AC secretion. Also, the IL-1 receptor antagonist, IL1RA, and caspase-1 inhibitor, Ac-YVAD, both inhibited MUC5AC secretion induced by cholesterol crystals. We found that inflammasome activation participates in cholesterol crystal induced mucin secretion and gallstone development.

Various Subtypes of EGFR Mutations in Patients With NSCLC Define Genetic, Immunologic Diversity and Possess Different Prognostic Biomarkers.

Based on data analysis of 9649 Chinese primary NSCLC patients, we calculated the exact proportion of EGFR subtypes in NSCLC and evaluated the TMB level, PD-L1 expression level and tumor immune microenvironment among different EGFR mutation subtypes. Postoperative follow-up data for 98 patients were collected and analyzed. The results showed that several uncommon EGFR mutation subtypes have a higher proportion of TMB-high or strong positive PD-L1 expression than the total EGFR mutation group. In addition, different subtypes have different characteristics related to the immune microenvironment, such as G719 mutations being associated with more CD8+ T cell infiltration into tumors; except for EGFR 19del, CD8+ T cell infiltration into tumors of other EGFR mutation subtypes were similar to that of wildtype EGFR. Moreover, follow-up results revealed that components of the immune microenvironment have prognostic value for NSCLC patients, with different prognostic biomarkers for NSCLC patients with and without EGFR mutations. These results suggest that patients with different EGFR mutations need to be treated differently. The prognosis of NSCLC patients may be assessed through components of tumor immune microenvironment, and ICIs treatment may be considered for those with some uncommon EGFR mutation subtypes.

Effects of Vessel Interruption Sequence During Lobectomy for Non-small Cell Lung Cancer: A Systematic Review and Meta-Analysis.

Background: For lobectomy in non-small cell lung cancer (NSCLC), whether interrupting the pulmonary vein first (Vein-first) achieves better perioperative and survival outcomes than interrupting the pulmonary artery first (Artery-first) remains controversial. We conducted this meta-analysis to compare outcomes between the two groups to facilitate better surgical decision-making. Methods: Web of Science, EMBASE, Cochrane Library, Ovid MEDLINE, PubMed, ScienceDirect, and Scopus were searched for eligible studies comparing Vein-first and Artery-first procedures. The primary endpoints were survival indicators [overall survival (OS), disease-free survival (DFS), and lung cancer-specific survival (LCSS)]. Secondary endpoints included intraoperative indicators, hospitalization, and follow-up indicators. Results: After screening 2,505 studies, 8 studies involving 1,714 patients (Vein-First group: 881 patients; Artery-first group: 833 patients) were included. The vein-first group achieved better OS [HR (hazard ratio): 1.46, 95% confidence interval (CI): 1.12-1.91, p = 0.005], DFS (HR: 1.60, 95% CI: 1.23-2.08, p < 0.001), and LCSS (HR: 1.64, 95% CI: 1.16-2.31, p = 0.005). The survival rates of OS at 2-5 years, DFS at 1-5 years, and LCSS at 3-5 years were also higher in the Vein-First group. Subgroup analyses suggested that the advantages of survival in the Vein-First group were primarily embodied in the subgroups of squamous cell carcinoma (SCC) and earlier pathological TNM stage (I-II). Operative time, intraoperative blood loss, total complications, and total recurrences were comparable between the two groups. Conclusions: The Vein-first sequence is the suitable choice of vessel interruption sequence during lobectomy for NSCLC with better survival and similar perioperative outcomes, especially for stage I-II SCC.

Identification of a novel autophagy signature for predicting survival in patients with lung adenocarcinoma.

BACKGROUND: Lung adenocarcinoma (LUAD) is the most commonhistological lung cancer subtype, with an overall five-year survivalrate of only 17%. In this study, we aimed to identify autophagy-related genes (ARGs) and develop an LUAD prognostic signature. METHODS: In this study, we obtained ARGs from three databases and downloaded gene expression profiles from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. We used TCGA-LUAD (n = 490) for a training and testing dataset, and GSE50081 (n = 127) as the external validation dataset.The least absolute shrinkage and selection operator (LASSO) Cox and multivariate Cox regression models were used to generate an autophagy-related signature. We performed gene set enrichment analysis (GSEA) and immune cell analysis between the high- and low-risk groups. A nomogram was built to guide the individual treatment for LUAD patients. RESULTS: We identified a total of 83 differentially expressed ARGs (DEARGs) from the TCGA-LUAD dataset, including 33 upregulated DEARGs and 50 downregulated DEARGs, both with thresholds of adjusted P < 0.05 and |Fold change| > 1.5. Using LASSO and multivariate Cox regression analyses, we identified 10 ARGs that we used to build a prognostic signature with areas under the curve (AUCs) of 0.705, 0.715, and 0.778 at 1, 3, and 5 years, respectively. Using the risk score formula, the LUAD patients were divided into low- or high-risk groups. Our GSEA results suggested that the low-risk group were enriched in metabolism and immune-related pathways, while the high-risk group was involved in tumorigenesis and tumor progression pathways. Immune cell analysis revealed that, when compared to the high-risk group, the low-risk group had a lower cell fraction of M0- and M1- macrophages, and higher CD4 and PD-L1 expression levels. CONCLUSION: Our identified robust signature may provide novel insight into underlying autophagy mechanisms as well as therapeutic strategies for LUAD treatment.

Integration of comprehensive genomic profiling, tumor mutational burden, and PD-L1 expression to identify novel biomarkers of immunotherapy in non-small cell lung cancer.

OBJECTIVES: This study aimed to explore the novel biomarkers for immune checkpoint inhibitor (ICI) responses in non-small cell lung cancer (NSCLC) by integrating genomic profiling, tumor mutational burden (TMB), and expression of programmed death receptor 1 ligand (PD-L1). MATERIALS AND METHODS: Tumor and blood samples from 637 Chinese patients with NSCLC were collected for targeted panel sequencing. Genomic alterations, including single nucleotide variations, insertions/deletions, copy number variations, and gene rearrangements, were assessed and TMB was computed. TMB-high (TMB-H) was defined as ≥10 mutations/Mb. PD-L1 positivity was defined as ≥1% tumor cells with membranous staining. Genomic data and ICI outcomes of 240 patients with NSCLC were derived from cBioPortal. RESULTS: EGFR-sensitizing mutations, ALK, RET, and ROS1 rearrangements were associated with lower TMB and PD-L1+/TMB-H proportions, whereas KRAS, ALK, RET, and ROS1 substitutions/indels correlated with higher TMB and PD-L1+/TMB-H proportions than wild-type genotypes. Histone-lysine N-methyltransferase 2 (KMT2) family members (KMT2A, KMT2C, and KMT2D) were frequently mutated in NSCLC tumors, and these mutations were associated with higher TMB and PD-L1 expression, as well as higher PD-L1+/TMB-H proportions. Specifically, patients with KMT2C mutations had higher TMB and PD-L1+/TMB-H proportions than wild-type patients. The median progression-free survival (PFS) was 5.47 months (95% CI 2.5-NA) in patients with KMT2C mutations versus 3.17 months (95% CI 2.6-4.27) in wild-type patients (p = 0.058). Furthermore, in patients with NSCLC who underwent ICI treatment, patients with TP53/KMT2C co-mutations had significantly longer PFS and greater durable clinical benefit (HR: 0.48, 95% CI: 0.24-0.94, p = 0.033). TP53 mutation combined with KMT2C or KRAS mutation was a better biomarker with expanded population benefit from ICIs therapy and increased the predictive power (HR: 0.46, 95% CI: 0.26-0.81, p = 0.007). CONCLUSION: We found that tumors with different alterations in actionable target genes had variable expression of PD-L1 and TMB in NSCLC. TP53/KMT2C co-mutation might serve as a predictive biomarker for ICI responses in NSCLC. IMPLICATIONS FOR PRACTICE: Cancer immunotherapies, especially immune checkpoint inhibitors (ICIs), have revolutionized the treatment of non-small cell lung cancer (NSCLC); however, only a proportion of patients derive durable responses to this treatment. Biomarkers with greater accuracy are highly needed. In total, 637 Chinese patients with NSCLC were analyzed using next-generation sequencing and IHC to characterize the unique features of genomic alterations and TMB and PD-L1 expression. Our study demonstrated that KMT2C/TP53 co-mutation might be an accurate, cost-effective, and reliable biomarker to predict responses to PD-1 blockade therapy in NSCLC patients and that adding KRAS to the biomarker combination creates a more robust parameter to identify the best responders to ICI therapy.

Identification of alternative splicing and lncRNA genes in pathogenesis of small cell lung cancer based on their RNA sequencing.

BACKGROUND: The molecular mechanisms involved in small-cell lung cancer (SCLC) are largely unknown. Recent studies have suggested that long non-coding RNAs (lncRNAs) are likely to play a critical role. OBJECTIVES: There is an urgent need for suitable molecular biomarkers for SCLC diagnosis and for assessing patient prognosis. MATERIAL AND METHODS: In this study, we used public databases to identify mRNA-like candidate lncRNAs. A multi-step computational approach was used to construct a functional SCLC lncRNAs-mediated competing with endogenous RNA (ceRNA) network (LMCN) by integrating genome-wide lncRNAs and mRNA expression profiles, miRNA-target interactions, functional analyses, and clinical survival analyses. RESULTS: The results revealed the significance of lncRNAs interactions with ceRNAs in SCLC, indicating that integration of expression profiles and alternative splicing could be used to identify biomarkers and the underlying pathological changes. The following genes: EPB41L4A-AS1, HOXA-AS2, XIST, DLEU2, FGD5-AS1, ALMS1-IT1, SNHG12, MIR17HG, MIR4720, and SCARNA10 in cluster, as well as shared alternative splicing events, were considered to be critical genes. CONCLUSIONS: Olfactory transduction and endocytosis were the top-enriched pathways in SCLC. The selected cluster, including critical genes, might also be a potential pathway of SCLC pathogenesis. As a result, this research provides the perspective information to explore the potential critical genes and its pathways in SCLC therapy.

Primary hepatoid adenocarcinoma of the lung in Yungui Plateau, China: A case report.

BACKGROUND: Hepatoid adenocarcinoma (HAC) occurs in extrahepatic organs such as the gastrointestinal tract, testes, ovaries, lungs, mediastinum and pancreas, and frequently produces α-fetoprotein (AFP). HAC of the lung (HAL) is rare, characterized by difficult treatment and poor prognosis. There are no reports of HAL in Yunnan-Guizhou Plateau, China. CASE SUMMARY: A 60-year-old male patient was clinically diagnosed with HAL pT3N0M0, stage IIB. Chest computed tomography revealed a 7.5 cm × 7.2 cm soft tissue mass located in the right lung upper lobe and the adjacent superior mediastinum. Right upper lobectomy was performed. The diagnosis of HAL was confirmed by pathological examination, and the patient received paclitaxel and carboplatin as adjuvant chemotherapy after surgery. CONCLUSION: Clinical manifestations, pathological features, imaging findings, auxiliary examination, and treatment planning of HAL are presented to help clinicians improve their diagnosis and treatment.

Stochastic resonance in a non-smooth system under colored noise excitations with a controllable parameter.

Stochastic resonance is studied in a class of non-smooth systems with a controllable parameter causing a change among monostability, bistability, and multistability, driven by colored noise. The system becomes smooth at a bifurcation point. Time scales in the non-smooth well are analyzed and transition rates of the non-smooth potential barriers are obtained. Analytical expressions for the response amplitude depending on the controllable parameter, frequency, noise intensity, and correlation time are derived in the bistable and multistable regions in the adiabatic limit. With the decrease of frequency, the optimal correlation time according to the maximum response is increasing; on the contrary, the optimal noise intensity is on the decline. Multistability of the system enhances the optimal transition rates and optimal response amplitude.

Stochastic chaos induced by diffusion processes with identical spectral density but different probability density functions.

Stochastic chaos induced by diffusion processes, with identical spectral density but different probability density functions (PDFs), is investigated in selected lightly damped Hamiltonian systems. The threshold amplitude of diffusion processes for the onset of chaos is derived by using the stochastic Melnikov method together with a mean-square criterion. Two quasi-Hamiltonian systems, namely, a damped single pendulum and damped Duffing oscillator perturbed by stochastic excitations, are used as illustrative examples. Four different cases of stochastic processes are taking as the driving excitations. It is shown that in such two systems the spectral density of diffusion processes completely determines the threshold amplitude for chaos, regardless of the shape of their PDFs, Gaussian or otherwise. Furthermore, the mean top Lyapunov exponent is employed to verify analytical results. The results obtained by numerical simulations are in accordance with the analytical results. This demonstrates that the stochastic Melnikov method is effective in predicting the onset of chaos in the quasi-Hamiltonian systems.

Interleukin-1ß-mediated suppression of microRNA-101 and upregulation of enhancer of zeste homolog 2 is involved in particle-induced lung cancer.

Lung cancer may be a result of complex factors. Small mineral particle is the well-known inducer of lung cancer. Previous study revealed the high morbidity of lung cancer in Xuan Wei in China, and the main cause of lung cancer is the use of smoky coal there. And it is generally accepted that chronic inflammation induced by small mineral particle may be a cause of lung cancer. But the relationship between chronic lung inflammation and lung cancer is largely unknown. In the present study, we found that silica particle was able to induce the secretion of interleukin-1ß from a Xuan Wei lung cancer cell line, XWLC-05. At the same time, microRNA-101 (mir-101) was found to be downregulated by the treatment of silica particle. Interestingly, the interleukin 1 receptor antagonist and interleukin-1ß antibody can reduce silica particle-induced downregulation of mir-101. Twenty-four Xuan Wei lung tumor tissues were collected to detect the expression level of mir-101 and enhancer of zeste homolog 2 (EZH2), which is the potential target of mir-101. The results showed that mir-101 was down-regulated and EZH2 were upregulated. Subsequently, the roles of mir-101 and EZH2 in tumor growth and progression in vitro were tested. Overexpression of mir-101 mimics was able to suppress the expression of EZH2 in XWLC-05 cells. And this resulted in the inhibited tumor cell growth and attenuated cell migration. The results in the present study showed that particle can induce the secretion of interleukin-1ß. Interleukin-1ß subsequently induces the downregulation of mir-101, which may result in the upregulated level of EZH2, and occurrence of lung cancer. We for the first time proposed the role interleukin-1ß-mir-101-EZH2 axes in the particle-induced lung cancer. Further study may be needed to decipher the detailed mechanism involved.