Preparation of Polyoxymethylene/Exfoliated Molybdenum Disulfide Nanocomposite through Solid-State Shear Milling.

In this paper, the solid-state shear milling (S3M) strategy featuring a very strong three-dimensional shear stress field was adopted to prepare the high-performance polyoxymethylene (POM)/molybdenum disulfide (MoS2) functional nanocomposite. The transmission electron microscope and Raman measurement results confirmed that the bulk MoS2 particle was successfully exfoliated into few-layer MoS2 nanoplatelets by the above simple S3M physical method. The polarized optical microscope (PLM) observation indicated the pan-milled nanoscale MoS2 particles presented a better dispersion performance in the POM matrix. The results of the tribological test indicated that the incorporation of MoS2 could substantially improve the wear resistance performance of POM. Moreover, the pan-milled exfoliated MoS2 nanosheets could further substantially decrease the friction coefficient of POM. Scanning electron microscope observations on the worn scar revealed the tribological mechanism of the POM/MoS2 nanocomposite prepared by solid-state shear milling. The tensile test results showed that the pan-milled POM/MoS2 nanocomposite has much higher elongation at break than the conventionally melt-compounded material. The solid-state shear milling strategy shows a promising prospect in the preparation of functional nanocomposite with excellent comprehensive performance at a large scale.

Aggrephagy-related gene signature correlates with survival and tumor-associated macrophages in glioma: Insights from single-cell and bulk RNA sequencing.

BACKGROUND: Aggrephagy is a lysosome-dependent process that degrades misfolded protein condensates to maintain cancer cell homeostasis. Despite its importance in cellular protein quality control, the role of aggrephagy in glioma remains poorly understood. OBJECTIVE: To investigate the expression of aggrephagy-related genes (ARGs) in glioma and in different cell types of gliomas and to develop an ARGs-based prognostic signature to predict the prognosis, tumor microenvironment, and immunotherapy response of gliomas. METHODS: ARGs were identified by searching the Reactome database. We developed the ARGs-based prognostic signature (ARPS) using data from the Cancer Genome Atlas (TCGA, n = 669) by Lasso-Cox regression. We validated the robustness of the signature in clinical subgroups and CGGA cohorts (n = 970). Gene set enrichment analysis (GSEA) was used to identify the pathways enriched in ARPS subgroups. The correlations between ARGs and macrophages were also investigated at single cell level. RESULTS: A total of 44 ARGs showed heterogeneous expression among different cell types of gliomas. Five ARGs (HSF1, DYNC1H1, DYNLL2, TUBB6, TUBA1C) were identified to develop ARPS, an independent prognostic factor. GSEA showed gene sets of patients with high-ARPS were mostly enriched in cell cycle, DNA replication, and immune-related pathways. High-ARPS subgroup had higher immune cell infiltration states, particularly macrophages, Treg cells, and neutrophils. APRS had positive association with tumor mutation burden (TMB) and immunotherapy response predictors. At the single cell level, we found ARGs correlated with macrophage development and identified ARGs-mediated macrophage subtypes with distinct communication characteristics with tumor cells. VIM+ macrophages were identified as pro-inflammatory and had higher interactions with malignant cells. CONCLUSION: We identified a novel signature based on ARGs for predicting glioma prognosis, tumor microenvironment, and immunotherapy response. We highlight the ARGs-mediated macrophages in glioma exhibit classical features.

A study of DNA transfers onto plastic packets placed in personal bags.

The ability to detect low level DNA brings with it the uncertainty of whether the detected DNA is a result of transfer. To address this uncertainty, a simulation study was conducted in which a mock illicit drug packet was placed into the personal bags of individuals. When the average transit time of the packets was increased from around 2 h to more than 14 h, the percentage of the DNA profiles recovered from the packets which could be attributed to the individuals increased greatly from 5.3% to 48.6%. We found that drug packers who were poor shedders could not be included as contributors to the DNA profiles from the drug packets at all and there was a higher chance that individuals other than themselves could be included as contributors to the DNA profile recovered from drug packets. We also found that it was equally likely that the drug packers who had direct contact with the drug packets and bag owners who did not, could be included as contributors to the DNA profiles recovered from the packets. The results in this study highlight the importance of taking into consideration the transit time of drug packet, the shedder status of the alleged packer and the history of an item, when evaluating DNA evidence in the context of illicit drug activities.

Protective effect of human epicardial adipose-derived stem cells on myocardial injury driven by poly-lactic acid nanopillar array.

We investigated if poly-lactic acid (PLA) nanopillar array can trigger the differentiation of human epicardial (ADSCs) (heADSCs) into cardiomyocyte-like cells and explored the effects of these cardiomyocyte-like cells on myocardial infarction (MI) in vivo. PLA nanopillar array (200 nm diameter) and plain PLA film (PLA planar) induced heADSCs were marked with carboxyfluorescein. After 7 days, the expressions of myocardiocyte-specific genes were significantly enhanced in cells seeded on PLA nanopillar array compared with that on PLA planar, especially CACNA1C, KCNH2, and MYL2 genes (p < 0.05). However, the expressions of cardiac troponin T (cTNT), KCNQ1, and KCNA5 were lower than those in PLA planar-induced heADSCs (p < 0.05), whereas GATA4 tended to increase with time. The cells with positively stained α-actinin and cTNT were elevated in heADSCs induced by PLA nanopillar array compared with those induced by PLA planar only (p < 0.05). In vivo experiments showed that cardiac function was improved after injecting PLA-nanopillar array-induced heADSCs into the ischemic heart (p < 0.05, compared with PLA planar + MI group). Furthermore, tyrosine hydroxylase density was significantly lower (p < 0.05). PLA nanopillar array directly drives the differentiation of heADSCs into cardiomyocyte-like cells, and the induced heADSCs exhibit a protective effect on ischemic myocardium by improving cardiac function in MI rats.

m6A methyltransferase METTL3 contributes to sympathetic hyperactivity post-MI via promoting TRAF6-dependent mitochondrial ROS production.

OBJECTIVES: N6-methyladenosine (m6A) is the most prevalent post-translational modification in eukaryotic mRNA. Recently, m6A editing modified by methyltransferase-like enzyme 3 (METTL3), the core m6A methyltransferase, has been demonstrated to be involved in cardiac sympathetic hyperactivity. This study aimed to clarify the effects and underlying mechanisms of METTL3 in the paraventricular nucleus (PVN) in mediating sympathetic activity following myocardial infarction (MI). METHODS: We established rat MI models by left anterior descending coronary artery ligation. m6A quantification was performed.The expression of METTL3 and its downstream gene, tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6), were determined. The functional role of METTL3 in sympathetic hyperactivity and electrical conduction stability were verified by assessing renal sympathetic nerve activity (RSNA), norepinephrine (NE) levels, and programmed electrical stimulation. Rescue experiments were also conducted. The mechanism by which m6A is involved in mitochondrial reactive oxygen species (mROS) production, mediated by TRAF6/ECSIT pathway, was explored in lipopolysaccharide (LPS) treated primary microglial cells. RESULTS: METTL3 was predominantly localized in the microglia and significantly increased within the PVN at 3 days post-MI. Inhibition of METTL3 decreased m6A levels, TRAF6 expression, and mROS production; downregulated sympathoexcitation, indicated by attenuated NE concentration and RSNA; decreased the incidence of ventricular tachycardia or fibrillation; and improved cardiac function. Mechanistically, downregulation of METTL3 prevented TRAF6 translocation to the mitochondria in the microglia and subsequent TRAF6/ECSIT pathway activation, resulting in decreased mROS production. CONCLUSIONS: This study demonstrates that METTL3-mediated m6A modification promotes sympathetic hyperactivity through TRAF6/ECSIT pathway and mitochondrial oxidative stress in the PVN, thereby leading to ventricular arrhythmias post-MI.

Performance Enhancement of PLA-Based Blend Microneedle Arrays through Shish-Kebab Structuring Strategy in Microinjection Molding.

Poly(lactic acid) (PLA) microneedles have been explored extensively, but the current regular fabrication strategy, such as thermoforming, is inefficient and poorly conformable. In addition, PLA needs to be modified as the application of microneedle arrays made of pure PLA is limited because of their easy tip fracture and poor skin adhesion. For this purpose, in this article, we reported a facile and scalable strategy to fabricate the microneedle arrays of the blend of PLA matrix and poly(p-dioxanone) (PPDO) dispersed phase with complementary mechanical properties through microinjection molding technology. The results showed that the PPDO dispersed phase could be in situ fibrillated under the effect of the strong shear stress field generated in micro-injection molding. These in situ fibrillated PPDO dispersed phases could hence induce the formation of the shish-kebab structures in the PLA matrix. Particularly for PLA/PPDO (90/10) blend, there are the densest and most perfect shish-kebab structures formed. The above microscopic structure evolution could be also advantageous to the enhancement in the mechanical properties of microparts of PLA/PPDO blend (tensile microparts and microneedle arrays), e.g., the elongation at break of the blend is almost double that of pure PLA while still maintaining the high stiffness (Young's modulus of 2.7 GPa) and the high strength (tensile strength of 68.3 MPa) in the tensile test, and relative to pure PLA, there is 100% or more increase in the load and displacement of microneedle in the compression test. This could open up new spaces for expanding the industrial application of the fabricated microneedle arrays.

Shedder status-An analysis over time and assessment of various contributing factors.

The shedder status of a person is an important consideration when evaluating probabilities of DNA transfer during activity-level assessments. As an extension of our previously published study, the shedder statuses of 38 individuals were reassessed 1 year later. The study found that shedder status may change over time for some individuals and was associated with one's gender, number of items touched, and mobile phone usage. In 29% of touch events, no DNA allele was detected and in 99% of touch events, the amount of DNA deposited was <2 ng. The study also found that in 0.6% of touch events, the participant could be excluded as a contributor of the observed DNA profile, with another person being included. Additionally, our investigations suggest that the current three-category system for shedder status classification may require further refinement to better represent the individuals' shedder status in a population.

Clinical Validation of Tagmentation-Based Genome Sequencing for Germline Disorders.

Genome sequencing (GS) is a powerful clinical tool used for the comprehensive diagnosis of germline disorders. GS library preparation typically involves mechanical DNA fragmentation, end repair, and bead-based library size selection followed by adapter ligation, which can require a large amount of input genomic DNA. Tagmentation using bead-linked transposomes can simplify the library preparation process and reduce the DNA input requirement. Here we describe the clinical validation of tagmentation-based PCR-free GS as a clinical test for rare germline disorders. Compared with the Genome-in-a-Bottle Consortium benchmark variant sets, GS had a recall >99.7% and a precision of 99.8% for single nucleotide variants and small insertion-deletions. GS also exhibited 100% sensitivity for clinically reported sequence variants and the copy number variants examined. Furthermore, GS detected mitochondrial sequence variants above 5% heteroplasmy and showed reliable detection of disease-relevant repeat expansions and SMN1 homozygous loss. Our results indicate that while lowering DNA input requirements and reducing library preparation time, GS enables uniform coverage across the genome as well as robust detection of various types of genetic alterations. With the advantage of comprehensive profiling of multiple types of genetic alterations, GS is positioned as an ideal first-tier diagnostic test for germline disorders.

The protective effect of gamma aminobutyric acid B receptor activation on sympathetic nerve remodeling via the regulation of M2 macrophage polarization after myocardial infarction.

INTRODUCTION & OBJECTIVES: Acute myocardial infarction (AMI) in coronary heart disease is a leading cause of sudden death primarily due to malignant ventricular arrhythmias (VAs). Inflammatory cell infiltration and inflammation-induced overactivation of sympathetic nerves are the major cause of VAs in AMI pathophysiological processes. Type 2 macrophages play an anti-inflammatory role in AMI. Targeting macrophages may be a therapeutic strategy to prevent VAs post AMI. We found that gamma aminobutyric acid (GABA) promotes macrophages polarized to M2 and hypothesized that GABA might exert anti-inflammatory effects by promoting type 2 macrophage polarization in AMI. We aim to characterized GABAB receptor distribution, function, and mechanisms in M2 macrophage polarization and explored the functional aspect of GABAB receptor activation in sympathetic remodeling. RESULTS: Gamma aminobutyric acid B receptors were expressed on macrophage surface both in vitro and in vivo. GABAB receptor agonist baclofen, GABA promoted macrophage switch to M2. While GABAB receptor antagonist CGP52432 blocked a baclofen induced switch to M2 polarization. GABA and baclofen increased M2 macrophage percentage and CGP52432 blocked this process in vivo. Also, IL-10 and TGF-ß1 released by M2 were increased in both AMI and baclofen/AMI group; Serum NE levels were decreased by baclofen. All the above effects were reversed by CGP52432 treatment. Baclofen decreased TH and GAP-43 staining while CGP52432 enhanced their expression post AMI indicating GABAB receptor activation inhibited sympathetic nerve sprouting and activity by reducing NE release. CONCLUSIONS: Gamma aminobutyric acid B receptor activation promoted M2 polarization and protested AMI heart by regulating sympathetic nerve remodeling.

Direct Z-Scheme SnSe2/SnSe Heterostructure Passivated by Al2O3 for Highly Stable and Sensitive Photoelectrochemical Photodetectors.

To mimic the natural photosynthesis system, a Z-scheme heterostructure is proposed as a viable and effective strategy for efficient solar energy utilization such as photocatalysis and photoelectrochemical (PEC) water splitting due to the high carrier separation efficiency, fast charge transport, strong redox, and wide light absorption. However, it remains a huge challenge to form a direct Z-scheme heterostructure due to the internal electric-field restriction and vital band-alignment at the interface. Herein, the van der Waals heterostructure based on the allotrope SnSe2 and SnSe is designed and synthesized by a two-step vapor phase deposition method to overcome the limitation in the formation of the Z-scheme heterostructure for the first time. The Z-scheme heterostructure of SnSe2/SnSe is confirmed by X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, PEC measurement, density functional theory calculations, and water splitting. Strikingly, the PEC photodetectors based on the Z-scheme heterostructure show a synergistic effect of superior stability from SnSe and fast photoresponse from SnSe2. As such, the SnSe2/SnSe Z-scheme heterostructure shows a good photodetection performance in the ultraviolet to visible wavelength range. Furthermore, the photodetector shows a faster response/recovery time of 13/14 ms, a higher photosensitivity of 529.13 µA/W, and a higher detectivity of 4.94 × 109 Jones at 475 nm compared with those of single components. Furthermore, the photodetection stability of the SnSe2/SnSe is also greatly improved by a-thin-Al2O3-layer passivation. The results imply the promising rational design of a direct Z-scheme heterostructure with efficient charge transfer for high performance of optoelectronic devices.

EphrinB2-RhoA upregulation attenuates sympathetic hyperinnervation and decreases the incidence of ventricular arrhythmia after myocardial infarction.

BACKGROUND: Cardiac sympathetic hyperinnervation after myocardial infarction (MI) is associated with a high incidence of lethal arrhythmia. Erythropoietin-producing hepatoma interactor B2 (EphrinB2), a diffusible axonal chemorepellent that can induce growth cone collapse and axon repulsion of several neuronal populations, is crucial in neurodevelopment during disease development and progression. However, whether EphrinB2 could inhibit cardiac sympathetic hyperinnervation after MI remains unclear. METHODS AND RESULTS: A rat model of MI was developed by left anterior descending coronary artery ligation. EphrinB2 expression was markedly increased in the infarcted border at 3 days after MI. Downregulation of EphrinB2 by intramyocardial injection of lentivirus carrying EphrinB2-shRNA significantly increased sympathetic hyperinnervation along with downregulated RhoA expression. In contrast, injection of EphrinB2-overexpressing lentivirus markedly upregulated EphrinB2, concomitant with inhibition of sympathetic sprouting and upregulated RhoA expression, accompanied by decreased incidence of ventricular arrhythmias (VAs). However, co-administering EphrinB2-overexpressing lentivirus and Fasudil (Rho kinase inhibitor) nearly abolished the inhibition of nerve sprouting effect. Additionally, EphrinB2 expression did not affect nerve growth factor level in the infarcted heart. CONCLUSIONS: Overexpression of EphrinB2 may ameliorate MI-induced sympathetic hyperinnervation and further reduce the incidence of VAs, at least in part by activating RhoA-mediated axonal retraction.

[Value of soluble triggering receptor expression on myeloid cells-1 level of alveolar fluid in early diagnosis of ventilator-associated pneumonia: a Meta-analysis].

OBJECTIVE: Serum soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) is a useful biomarker of bacterial infection. However, the diagnostic value of sTREM-1 of alveolar fluid in pulmonary infection is still unclear. This article aimed to explore the value of sTREM-1 of alveolar fluid in the early diagnosis of ventilator-associated pneumonia (VAP) by systematic review of relevant literatures. METHODS: CNKI, Wanfang, VIP, PubMed/Medline and Embase databases were retrieved. Articles on diagnosis of VAP by sTREM-1 before June 30, 2019 were collected. QUADAS-2 scale provided by Cochrane Collaboration Network was used to evaluate the quality of diagnostic experiments. RevMan 5.3 and Stata 13.0 software were used to complete Meta-analysis. The levels of sTREM-1 between VAP and non-VAP patients were analyzed by Meta-analysis, and then diagnostic test Meta-analysis was conducted. Heterogeneity, sensitivity and publication bias were analyzed. RESULTS: A total of 24 articles were enrolled. QUADAS-2 scale indicated that the selected literature had low bias and high clinical adaptability. (1) In Meta-analysis of sTREM-1 level in alveolar fluid, 20 articles were selected and found to have high heterogeneity (I2 = 94.4%, P = 0.000). The random effects models were used for Meta-analysis. It was indicated that the sTREM-1 level in alveolar fluid of VAP group was significantly higher than that of non-VAP group with significant difference [standardized mean difference (SMD) was 1.47, 95% confidence interval (95%CI) was 1.00-1.95, Z = 6.14, P = 0.000]. By subgroup analysis and Meta-regression analysis, no source of heterogeneity was found. Sensitivity analysis suggested that the results of this Meta-analysis were robust and credible, and Begg funnel plot analysis showed that there was no significant publication bias (Z = 1.46, P = 0.143). (2) A total of 18 articles were included in the Meta-analysis of diagnostic experiments. Deek funnel plot showed publication bias (P = 0.012). The combined sensitivity was 0.87 (95%CI was 0.81-0.91), specificity was 0.80 (95%CI was 0.73-0.86), and diagnostic odds ratio (DOR) was 26 (95%CI was 13-50). Subgroup analysis of three different sources of alveolar fluid (bronchoalveolar lavage fluid, endotracheal aspiration fluid and exhaled ventilator condensate) showed that STREM-1 had a certain value in early diagnosis of VAP. The I2 of combined DOR was 35.4%, and I2 of sensitivity was 79.46%, I2 of specificity was 77.61%, suggesting heterogeneity in the selected literature. Subgroup analysis found that nationality, subject design, sample source, sample size and diagnostic "gold criteria" were related to heterogeneity, but not age. The area under synthetic receiver operating characteristic (SROC) curve (AUC) was 0.90 (95%CI was 0.87-0.92). CONCLUSIONS: The detection of sTREM-1 level in alveolar fluid can be used for the early diagnosis of VAP with high sensitivity and specificity. If combined with other biomarkers, it may have more diagnostic value.

Targeting blockade of nuclear factor-κB in the hypothalamus paraventricular nucleus to prevent cardiac sympathetic hyperinnervation post myocardial infarction.

BACKGROUND AND OBJECTIVES: Nuclear factor-κB (NF-κB) is considered to be a master inflammation regulator and involved in sympathetic neural hyperinnervation after myocardial infarction (MI). Paraventricular nucleus (PVN), acts as the sympathetic outflow tract, has been proven to play an important role during MI, but whether NF-κB pathway in the PVN participates in the pathogenesis of sympathetic sprouting and reinnervation after MI are unclear. METHODS AND RESULTS: MI was induced by coronary artery ligation, NF-κB was activated and interleukin-1ß (IL-1ß) and nerve growth factor (NGF) levels were increased in the PVN after MI. Lipopolysaccharide (LPS) stimulation also can activate NF-κB pathway, followed by increasing the expressions of IL-1ß and NGF in the PVN, once combining with gevokizumab (an IL-1ß inhibitor) significantly reduced the expressions of IL-1ß and NGF, but could not affect the NF-κB expression in the PVN. Furthermore, micro-injection of the NF-κB inhibitor pyrrolidine dithiocarbamate into PVN in MI rats, significantly inhibited the activation of NF-κB and further reduced the expression of IL-1ß and NGF in the PVN, finally blunting sympathetic hyperinnervation in the heart, moreover, the blockade of NF-κB in the PVN reduced the incidence of ventricular arrhythmias (VAs). CONCLUSIONS: Cardiac nerve sprouting after MI is associated in part with NF-κB activation in the PVN, and IL-1ß is involved in the process. Targeting blockade of NF-κB in the PVN may be a potential approach to ameliorate sympathetic hyperinnervation and reduce the incidence of VAs after MI.

A novel sympathetic neuronal GABAergic signalling system regulates NE release to prevent ventricular arrhythmias after acute myocardial infarction.

AIM: Overactivation of the sympathetic nerve may lead to severe ventricular arrhythmias (VAs) after myocardial infarction (MI). Thus, targeting sympathetic nerve activity is an effective strategy to prevent VAs clinically. The superior cervical ganglion (SCG), the extracardiac sympathetic ganglion innervating cardiac muscles, has been found to have a GABAergic signalling system, the physiological significance of which is obscure. We aimed to explore the functional significance of SCG post MI and whether the GABAergic signal system is involved in the process. METHODS: Adult male Sprague-Dawley rats were divided into seven different groups. Rats in the MI groups underwent ligation of the left anterior descending coronary artery. All animals were used for electrophysiological testing, renal sympathetic nerve activity (RSNA) testing, and ELISA. Primary SCG sympathetic neurons were used for the in vitro study. RESULTS: The GABAA receptor agonist muscimol significantly decreased the ATP-induced increase in intracellular Ca2+ (P < 0.05). GABA treatment in MI rats significantly attenuated the level of serum and cardiac norepinephrine (NE; P < 0.05). Sympathetic activity and inducible VAs were also lower in MI + GABA rats than in MI rats (P < 0.05). Knockdown of the GABAA Rs ß2 subunit (GABAA Rß2 ) in the SCG of MI rats increased the NE levels in serum and cardiac tissue, RSNA and inducible VAs compared with vehicle shRNA (P < 0.05). CONCLUSION: The GABAergic signalling system is functionally expressed in SCG sympathetic neurons, and activation of this system suppresses sympathetic activity, thereby facilitating cardiac protection and making it a potential target to alleviate VAs.

TLR4 participates in sympathetic hyperactivity Post-MI in the PVN by regulating NF-κB pathway and ROS production.

Sympathetic nerve hyperactivity is a primary reason for fatal ventricular arrhythmias (VAs) following myocardial infarction (MI). Pro-inflammatory cytokines produced in the paraventricular nucleus (PVN) post-MI are associated with sympathetic overexcitation; however, the precise mechanism needs further investigation. Our aim was to explore the mechanism of toll-like receptor 4 (TLR4) and its downstream molecular pathway in mediating sympathetic activity post-MI within the PVN. A rat MI model was developed via left anterior descending coronary artery ligation. TLR4 was primarily localized in microglia and increased markedly within the PVN at 3 days in MI rats. Sympathoexcitation also increased, as indicated by high levels of renal sympathetic nerve activity (RSNA) and norepinephrine (NE) concentration. TLR4 knockdown via shRNA microinjection to the PVN resulted in decreased activation of Fos protein (+) neurons in the PVN and peripheral sympathetic nerve activity. TLR4 knockdown also exhibited a lower arrhythmia score following programmed electrical stimulation than those treated with MI surgery only, indicating that the knockdown of TLR4 decreased the incidence of malignant ventricular arrhythmias following MI. LPS-induced inflammatory response was analyzed to explore the underlying mechanism of TLR4 in sympathetic hyperactivity. High levels of NF-κB protein, the pro-inflammatory cytokines IL-1ß and TNF-α, and ROS production were observed in the LPS group. PVN-targeted injection of the NF-κB inhibitor PDTC attenuated NF-κB expression and sympathetic activity. Taken together, the results suggested that knockdown of microglial TLR4 within the PVN decreased sympathetic hyperactivity and subsequent VAs post-MI. The downstream NF-κB pathway and ROS production participated in the process. Interventions targeting TLR4 signaling in the PVN may be a novel approach to ameliorate the incidence of VAs post-MI.

Targeted regulation of sympathetic activity in paraventricular nucleus reduces inducible ventricular arrhythmias in rats after myocardial infarction.

BACKGROUND: The hypothalamic paraventricular nucleus (PVN) is the center of the regulation of autonomic nervous system functions and cardiovascular activity. Phosphoinositide-3 kinase (PI3K)-AKT pathway in PVN contributes to mediate sympathetic nerve activity and is activated in spontaneously hypertensive rats. Overactivation of the sympathetic output was considered as an important mechanism of the arrhythmias. In the present study, we aimed to explore whether targeted regulation of sympathetic activity in PVN could reduce the peripheral sympathoexcitatory and attenuate the ventricular arrhythmias (VAs) in myocardial infarction (MI) rats via PI3K-AKT pathway. METHODS: A stainless steel gauge guide cannula was stereotaxically implanted into the PVN, and 7 days later, rats were randomly divided into the following 4 groups: group A, control+dimethyl sulfoxide (DMSO); group B, control+LY294002; group C, MI surgery+DMSO; and group D, MI surgery+LY294002. Studies were conducted seven days post-MI. Myocardial function, infarct size, inducible VAs by programmed electrical stimulation, renal sympathetic nerve activity (RSNA), and protein level of PI3K and AKT were measured. RESULTS: MI increased the protein ratios of p-PI3K-to-total-PI3K and p-AKT-to-total-AKT in PVN but can be reduced by LY294002 treatment. Inhibition of sympathetic nerve activity in PVN led to a reversion in plasma norepinephrine, RSNA and inducible VAs in MI rats. CONCLUSIONS: PI3K-AKT pathway in the PVN was a main mechanism in regulating sympathetic activity and arrhythmias in MI rats. Targeted inhibition of sympathetic activity in PVN may be a potential treatment for the VAs via PI3K-AKT pathway.

Microglial Mincle receptor in the PVN contributes to sympathetic hyperactivity in acute myocardial infarction rat.

Malignant ventricular arrhythmias (VAs) following myocardial infarction (MI) is a lethal complication resulting from sympathetic nerve hyperactivity. Numerous evidence have shown that inflammation within the paraventricular nucleus (PVN) participates in sympathetic hyperactivity. Our aim was to explore the role of Macrophage-inducible C-type lectin (Mincle) within the PVN in augmenting sympathetic activity following MI,and whether NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome/IL-1ß axis is involved in this activity. MI was induced by coronary artery ligation. Mincle expression localized in microglia within the PVN was markedly increased at 24 hours post-MI together with sympathetic hyperactivity, as indicated by measurement of the renal sympathetic nerve activity (RSNA) and norepinephrine (NE) concentration. Mincle-specific siRNA was administrated locally to the PVN, which consequently decreased microglial activation and sympathetic nerve activity. The MI rats exhibited a higher arrhythmia score after programmed electric stimulation than that treated with Mincle siRNA, suggesting that the inhibition of Mincle attenuated foetal ventricular arrhythmias post-MI. The underlying mechanism of Mincle in sympathetic hyperactivity was investigated in lipopolysaccharide (LPS)-primed naïve rats. Recombinant Sin3A-associated protein 130kD (rSAP130), an endogenous ligand for Mincle, induced high levels of NLRP3 and mature IL-1ß protein. PVN-targeted injection of NLRP3 siRNA or IL-1ß antagonist gevokizumab attenuated sympathetic hyperactivity. Together, the data indicated that the knockdown of Mincle in microglia within the PVN prevents VAs by attenuating sympathetic hyperactivity and ventricular susceptibility, in part by inhibiting its downstream NLRP3/IL-1ß axis following MI. Therapeutic interventions targeting Mincle signalling pathway could constitute a novel approach for preventing infarction injury.

Screening and verification of proteins that interact with HSPC238.

HSPC238 is a recently identified tumor suppressor and demonstrates ubiquitin ligase E3 enzyme activity. HSPC238 was found to be significantly downregulated in human hepatocellular carcinoma (HCC) in vivo and to inhibit the proliferation and invasion of hepatoma cells in vitro; however, the underlying molecular mechanism is largely unknown. In the present study, we screened for and identified proteins that physically interact with HSPC238. A bait vector for yeast two-hybrid was constructed with human HSPC238 gene cDNA. Yeast two-hybrid screening was performed using a human fetal liver cDNA library. Multiple reporter gene assays, DNA sequencing and BLAST comparison analysis were performed on positive clones. Protein interaction of screened candidates with HSPC238 was further validated by confocal microscopy, co-immunoprecipitation and pull-down assays. Yeast two-hybrid screening demonstrated 124 positive clones. Multiple reporter gene assays with LacZ, HIS and ADE2 selective media identified 12 genes. Further co-localization, co-immunoprecipitation and pull-down assays demonstrated that HMOX1, RPS27A, ubiquitinB and MT2A interacted with HSPC238. These four proteins are involved in tumor development and progression, and are associated with the ubiquitin-proteasome pathway. Our results suggest that HSPC238 may play a tumor suppressor role and interact with these proteins via the ubiquitin-proteasome pathway. The identification and validation of proteins interacting with HSP238 may lead to the discovery of novel mechanisms through which HSPC238 suppresses tumorigenesis in human hepatocellular carcinoma.

PSMA7 inhibits the tumorigenicity of A549 human lung adenocarcinoma cells.

The gene for proteasome subunit alpha type-7 (PSMA7) is located in chromosomal 20q13.33, a region frequently amplified in tumor. In this study, we employed A549 human lung adenocarcinoma cells and showed that PSMA7 inhibits the proliferation, tumorigenicity and invasion of A549 cells in vitro. Moreover, both gain and loss of function studies demonstrated that PSMA7 modulates the tumorigenicity of A549 cells in a xenograft nude mice model. In conclusion, these results identify inhibitory effects associated with PSMA7 that affect the tumorigenicity of A549 cells, suggesting PSMA7 as a potential tumor biomarker.