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Li Song

Publications and source records attributed to Li Song.

At least 19 recordsLinked to original sources
PubMed2026

Chronic heart failure and GPX3 promoter methylation: A clinical-epigenetic analysis.

BACKGROUND: Selenoprotein GPX3 is linked to Chronic Heart Failure (CHF), but its promoter methylation patterns in CHF remain unclear. OBJECTIVE: To explore CpG methylation in the GPX3 promoter region and its association with clinical parameters in CHF. METHODS: Twenty CHF patients and twenty healthy controls were included. Methylation levels of CpG sites within the GPX3_FA28 promoter region were quantified. Group differences were assessed using appropriate statistical tests. Restricted cubic spline (RCS) models were applied to explore dose-response associations between differentially methylated CpG sites and clinical indicators across multiple physiological systems. RESULTS: Significant locus-specific methylation alterations were identified in CHF patients. CpG_5 showed hypermethylation (P = 0.017), while CpG_9 (P = 0.045) and CpG_19 (P = 0.008) were hypomethylated compared with controls. Patients with NYHA class I/II exhibited higher methylation at CpG_1 (P = 0.028) and CpG_2 (P = 0.040). CpG_5 methylation displayed nonlinear associations (P < 0.05) with total bilirubin (inverted U-shape), carbon dioxide (triphasic), total cholesterol (U-shape), and plateletcrit (wave-like). CpG_9 correlated with activated partial thromboplastin time and hematopoietic markers, while CpG_19 was linked to eosinophil percentage and erythrocyte parameters. CONCLUSIONS: GPX3 promoter methylation displays apparent locus specificity in CHF. Different CpG sites may contribute to CHF pathophysiology through distinct epigenetic mechanisms. These findings highlight the potential of GPX3 methylation as a stratified biomarker in CHF.

Humans↗
PubMed2025

Rice transcription factor bHLH25 confers resistance to multiple diseases by sensing H2O2.

Hydrogen peroxide (H2O2) is a ubiquitous signal regulating many biological processes, including innate immunity, in all eukaryotes. However, it remains largely unknown that how transcription factors directly sense H2O2 in eukaryotes. Here, we report that rice basic/helix-loop-helix transcription factor bHLH25 directly senses H2O2 to confer resistance to multiple diseases caused by fungi or bacteria. Upon pathogen attack, rice plants increase the production of H2O2, which directly oxidizes bHLH25 at methionine 256 in the nucleus. Oxidized bHLH25 represses miR397b expression to activate lignin biosynthesis for plant cell wall reinforcement, preventing pathogens from penetrating plant cells. Lignin biosynthesis consumes H2O2 causing accumulation of non-oxidized bHLH25. Non-oxidized bHLH25 switches to promote the expression of Copalyl Diphosphate Synthase 2 (CPS2), which increases phytoalexin biosynthesis to inhibit expansion of pathogens that escape into plants. This oxidization/non-oxidation status change of bHLH25 allows plants to maintain H2O2, lignin and phytoalexin at optimized levels to effectively fight against pathogens and prevents these three molecules from over-accumulation that harms plants. Thus, our discovery reveals a novel mechanism by which a single protein promotes two independent defense pathways against pathogens. Importantly, the bHLH25 orthologues from available plant genomes all contain a conserved M256-like methionine suggesting the broad existence of this mechanism in the plant kingdom. Moreover, this Met-oxidation mechanism may also be employed by other eukaryotic transcription factors to sense H2O2 to change functions.

Hydrogen Peroxide↗
PubMed2025

Phylogenetic and Genetic Evolution Analysis of Complete SFTSV Genome Sequences in Shandong Province, China.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by SFTS virus (SFTSV). Shandong province is one of the epidemic regions with high incidence rate of SFTS. To investigate phylogenetical and genetic evolution characteristics of SFTSV in Shandong province, we isolated SFTSV from suspected patients between April 2023 and October 2024, and then whole SFTSV genomes were amplified and sequenced in this study. A total of 25 new strains were analyzed together 56 strains submitted in Genbank from Shandong province. Phylogenetical and genetic analyses of the data set revealed that four genotypes were co-circulating in Shandong province. C3 genotype was the most common genotype in each year with lower genetic divergence. 298 amino acid substitutions were detected in the four proteins of SFTSV, but only two substitutions (Arg624Lys and Arg962Ser) had been proven to have potential impacts on biological functions. In addition, one reassortment strain (C3/C4/C4 for L, M and S segments) and three recombinant strains were identified. Analysis of selection pressure at the level of amino acid substitutions indicated genes within the four ORFs of SFTSV were all subjected to negative selection. In conclusion, the genetic characteristics and evolutionary mechanism of SFTSV was complex in Shandong province. It is necessary to conduct continuous surveillance to grasp the genetic evolution patterns, and to discover novel prevalent variants in a timely manner.

China↗
PubMed2006

Synthesis and crystal structures of multidimensional coordination polymers based on W/Cu/S clusters with flexible imidazole ligands.

Reactions of [WES3]2- (E = S, O) with CuX (X = NCS, CN, I) in the presence of bix (bix = 1,4-bis(imidazole-1-ylmethyl)benzene) in DMF or CH3CN resulted in the formation of two novel 2D --> 3D interpenetrating coordination polymers [S2W2S6Cu4(bix)2]n (1) and {[WS4Cu4(NCS)2(bix)3].CH3CN}n (2), a noninterpenetrating 3D polymer {[WS4Cu2(bix)].DMF}n (3), and two 2D sheet polymers [WS4Cu3(CN)(bix)]n (4) and {[OWS3Cu3(bix)2][I].DMF.2H2O}n (5), depending on the reaction temperature and the reagents used. Compound 1 contains a hexagonal prism of W2Cu4S6 cluster core, which serves as a 4-connecting node to link equivalent nodes via bix ligands, forming a 2D (4,4) net. In 2, a WCu4S4 core, which also acts as a 4-connecting node, connects the neighboring nodes either through single or double bix bridges, affording a different 2D (4,4) sheet. Inclined interpenetration occurs between two stacks of 2D sheets in the total structure of 1, while 2 involves a parallel interpenetration between the adjacent layers, both creating a 3D network. Compounds 1 and 2 represent the first examples of interpenetrating (4,4) frameworks with clusters as nodes and bidentate pyridyl-based ligands as linkers. Unlike 1 and 2, compound 3 has a noninterpenetrating 3D network, which is composed of the inorganic 1D (WS4Cu2)n chains linked by cis and trans bix ligands. Compound 4 features an inorganic 1D (WS4Cu3)n chain structure, which is linked by CN groups and bix ligands to form an infinite 2D network. Compound 5 is a 2D layer polymer with large inner cavities.

Journal Article↗
PubMed2006

Structural, magnetic, and magnetoresistive properties of electrodeposited Ni5Zn21 alloy nanowires.

Ni5Zn21 alloy nanowires were fabricated through template-assisted electrochemical deposition method. The morphology and microstructures of as-deposited nanowires were determined by field-emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), electron diffraction (ED), and electron probe microanalysis (EPMA). The accurate composition was measured via induced coupling plasma atomic emission spectroscopy. SEM results show that Ni5Zn21 nanowires are deposited in most of the nanopores of the template, and they are continuous and dense throughout the whole length. The XRD result demonstrates that the nanowires are mainly composed of a cubic gamma phase Ni5Zn21 alloy, but there also exists a trace of Zn-rich eta phase. HRTEM and ED reveal that the alloy nanowires are polycrystalline with the crystallite size of several tens of nanometers. EPMA of a single nanowire illustrates that there exist Ni-rich microzones in as-deposited nanowires. Subsequent magnetic measurements of the array also confirmed the existence of them. In addition, it can be further inferred that the shape of Ni-rich microzones is probably barlike or disklike, from the anisotropy of zero field cooling/field cooling (ZFC/FC) curves as well as the vortex magnetization behavior of the Ni5Zn21 nanowire array. The low-temperature magnetoresistance of the Ni5Zn21 nanowire array was also measured. Giant magnetoresistance instead of anisotropic magnetoresistance is suggested to be responsible for contributing to the magnetoresistance.

Journal Article↗
PubMed2006

NF-kappaB regulation of endothelial cell function during LPS-induced toxemia and cancer.

The transcription factor NF-kappaB is an important regulator of homeostatic growth and inflammation. Although gene-targeting studies have revealed important roles for NF-kappaB, they have been complicated by component redundancy and lethal phenotypes. To examine the role of NF-kappaB in endothelial tissues, Tie2 promoter/enhancer-IkappaBalpha(S32A/S36A) transgenic mice were generated. These mice grew normally but exhibited enhanced sensitivity to LPS-induced toxemia, notable for an increase in vascular permeability and apoptosis. Moreover, B16-BL6 tumors grew significantly more aggressively in transgenic mice, underscoring a new role for NF-kappaB in the homeostatic response to cancer. Tumor vasculature in transgenic mice was extensive and disorganized. This correlated with a marked loss in tight junction formation and suggests that NF-kappaB plays an important role in the maintenance of vascular integrity and response to stress.

Animals↗
PubMed2006

Caveolin-1 regulates expression of junction-associated proteins in brain microvascular endothelial cells.

Recent evidence from this laboratory indicated that reduced expression of caveolin-1 accompanied the diminished expression of tight junction (TJ)-associated proteins occludin and zonula occludens-1 (ZO-1) following stimulation of brain microvascular endothelial cells (BMECs) with the chemokine CCL2 (formerly called MCP-1). Because attenuated caveolin-1 levels have also been correlated with heightened permeability of other endothelia, the objective of this study was to test the hypothesis that reduced caveolin-1 expression is causally linked to the action of CCL2 on BMEC junctional protein expression and barrier integrity. This was achieved using adenovirus to nondestructively deliver caveolin-1 siRNA (Ad-siCav-1) to BMEC monolayers, which model the blood-brain barrier (BBB). Treatment with siRNA reduced the caveolin-1 protein level as well as occludin and ZO-1. Additionally, occludin exhibited dissociation from the cytoskeletal framework. These changes were attended by comparable alterations in adherens junction (AJ)-associated proteins, VE-cadherin and beta-catenin, increased BMEC paracellular permeability, and facilitated the ability of CCL2 to stimulate monocytic transendothelial migration. Furthermore, treating BMECs with cavtratin, a synthetic cell-permeable peptide encoding the caveolin-1 scaffolding domain, antagonized effects of both Ad-siCav-1 and CCL2. These results collectively highlight caveolin-1 loss as a critical step in CCL2-induced modulation of BMEC junctional protein expression and integrity, and possibly serve a crucial role in regulating inflammation at the BBB.

Animals↗
PubMed2006

Identification of translational release factor eRF1a binding sites on eRF3 in Euplotes octocarinatus.

Translation termination in eukaryotes is mediated by two polypeptide chain-release factors, eRF1 and eRF3. eRF1 recognizes stop signals, while eRF3 is a ribosome-dependent and eRF1-dependent GTPase. eRF1 forms a stable complex with eRF3 in vivo and in vitro. In the present study, a variety of truncated forms of Euplotes octocarinatus eRF3 were created, and systematic analysis of the interaction between E. octocarinatus eRF1a and these eRF3 mutants was performed by employing both in vivo a yeast two-hybrid assay and in vitro a pull-down assay. The results demonstrated that a short portion of the C-terminal domain of eRF3 is sufficient for eRF1a binding in E. octocarinatus. Specifically, the eRF1a-binding sites on eRF3 are located at a region containing amino acid residues 640-723 in E. octocarinatus eRF3. Amino acid sequence analysis of eRF3 from E. octocarinatus, humans and yeast showed that the eRF1a binding domain on E. octocarinatus eRF3 was similar to that of yeast eRF3 but different from that of human eRF3.

Amino Acid Sequence↗
PubMed2006

Effect of shenfu injection on gastrointestinal microcirculation in rabbits after myocardial ischemia-reperfusion injury.

AIM: To investigate the effect of shenfu injection on gastrointestinal microcirculation after myocardial ischemic-reperfusion (IR) injury in rabbits and probe into the mechanism. METHODS: Forty healthy flap-eared white rabbits were randomly divided into 4 groups: IR injury control group (group I), shenfu injection 5 mL/kg per h group (group II), shenfu injection 10 mL/kg per h group (group III) and shenfu injection 20 mL/kg per h group (group IV). The four groups were treated with Lactated Ringer's solution, shenfu injection 5, 10, and 20 mL/ kg per h were infused intravenously 30 min before experiment respectively. The values of hemodynamics [mean arterial pressure (MAP), heart rate (HR), gastric intramucosal partial pressure of carbon dioxide (PCO2), blood gas analysis and pH] were measured and compared with those before myocardial ischemia, 60 min after myocardial ischemia and 60, 90, and 180 min after reperfusion. RESULTS: The MAP, HR and gastric intramucosal pH were (70.50 +/- 4.50) kPa, (165 +/- 14) beats per min, 7.032 +/- 0.024 in group I 60 min after myocardial ischemia, which were significantly decreased compared with those before myocardial ischemia (88.50 +/- 9.75 kPa, 217 +/- 18 beats per min, 7.112 +/- 0.035, P < 0.05). The MAP, HR and gastric intramucosal pH were significantly decreased in group I 60, 90, and 180 min after reperfusion (61.50 +/- 5.25 kPa, 133 +/- 31 beats per min, 6.997 +/- 0.025) compared with those before reperfusion respectively (P < 0.05), whereas the values were insignificantly different in groups II, III or IV after reperfusion, compared with those before reperfusion, and there were no significant differences between groups II, III, and IV after reperfusion. CONCLUSION: Pre-infusion of shenfu injection has a protective effect on gastrointestinal microcirculation after myocardial IR injury in rabbits, in a dose independent manner.

Animals↗
PubMed2006

Stat1 and SUMO modification.

Many proteins are known to undergo small ubiquitin-related modifier (SUMO) modification by an E1-, E2-, and E3-dependent ligation process. Recognition that protein inhibitor of activated signal transducers and activators of transcription (STATs) (PIAS) proteins are SUMO E3 ligases raised the possibility that STATs may also be regulated by SUMO modification. Consistent with this possibility, a SUMO-ylation consensus site (PsiKxE; Psi indicates hydrophobic residue, and x indicates any residue) was identified in Stat1 (ie, (702)IKTE(705)), but not in other STATs. Biochemical analysis confirmed that Stat1 K(703) could be SUMO modified in vitro. Mutation of this critical lysine (ie, Stat1(K703R)) yielded a protein that, when expressed in Stat1(-/-) mouse embryonic fibroblasts (MEFs), exhibited enhanced DNA binding and nuclear retention. This was associated with modest changes in transcriptional and antiviral activity. However, mutation of the second critical residue in the SUMO consensus site, E(705) (ie, Stat1(E705A)), yielded a protein with wild-type DNA binding, nuclear retention, and transcriptional and antiviral activity. Similar observations were made when these mutants were expressed in primary Stat1(-/-) macrophages. These observations suggest that although Stat1 can uniquely be SUMO-ylated in vitro, this modification is unlikely to play an important role in regulating Stat1 activity in vivo.

Animals↗
PubMed2006

Growth mechanism, photoluminescence, and field-emission properties of ZnO nanoneedle arrays.

ZnO nanoneedle arrays have been grown on a large scale with a chemical vapor deposition method at 680 degrees C. Zn powder and O(2) gas are employed as source materials, and catalyst-free Si plates are used as substrates. Energy-dispersive X-ray and X-ray diffraction analyses show that the nanoneedles are almost pure ZnO and preferentially aligned in the c-axis direction of the wurtzite structure. The growth mechanism of ZnO nanoneedle arrays is discussed with the thermodynamic theory and concluded to be the result of the co-effect of the surface tension and diffusion. Photoluminescence spectrum of the as-grown products shows a strong emission band centering at about 484 nm, which originates from oxygen vacancies. Field-emission examination exhibits that the ZnO nanoneedle arrays have a turn-on voltage at about 5.3 V/microm.

Journal Article↗
PubMed2006

Impairment of the spatial learning and memory induced by learned helplessness and chronic mild stress.

Increasing evidences indicate the concurrence and interrelationship of depression and cognitive impairments. The present study was undertaken to investigate the effects of two depressive animal models, learned helplessness (LH) and chronic mild stress (CMS), on the cognitive functions of mice in the Morris water maze task. Our results demonstrated that both LH and CMS significantly decreased the cognitive performance of stressed mice in the water maze task. The escaping latency to the platform was prolonged and the probe test percentage in the platform quadrant was reduced. These two models also increased the plasma corticosterone concentration and decreased the brain derived neurotrophic factor (BDNF) and cAMP-response element-biding protein (CREB) messenger ribonucleic acid (mRNA) levels in hippocampus, which might cause the spatial cognition deficits. Repeated treatment with antidepressant drugs, imipramine (Imi) and fluoxetine (Flu), significantly reduced the plasma corticosterone concentration and enhanced the BDNF and CREB levels. Furthermore, antidepressant treated animals showed an ameliorated cognitive performance compared with the vehicle treated stressed animals. These data suggest that both LH and CMS impair the spatial cognitive function and repeated treatment with antidepressant drugs decreases the prevalence of cognitive impairments induced by these two animal models. Those might in part be attributed to the reduced plasma corticosterone and enhanced hippocampal BDNF and CREB expressions. This study provided a better understanding of molecular mechanisms underlying interactions of depression and cognitive impairments, although animal models used in this study can mimic only some aspects of depression or cognition of human.

Animals↗
PubMed2006

Temperature dependence of the Raman spectra of individual carbon nanotubes.

Resonant Raman scattering (RRS) spectra of individual carbon nanotubes on a SiO2 substrate have been investigated first in the temperature range of 100-600 K (Phys. Rev. B 2002, 66, 115411). It was revealed by the intensity abnormality of the radial breathing mode (RBM) that the carbon nanotubes have a temperature-dependent density of electronic states. This means that the previously reported temperature coefficients of RBM of carbon nanotubes are smaller than their "real" ones for the bulk samples of single- or double-walled carbon nanotubes. Comparatively, the G line of individual nanotubes shows no observable difference relative to the bulk samples.

Journal Article↗
PubMed2006

Human fibrinogen adsorption onto single-walled carbon nanotube films.

The adsorption behavior of human fibrinogen (Hfg) on single-walled carbon nanotube (SWNT) films was investigated using scanning electron microscopy (SEM) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. It was shown in the SEM images that fibrinogen was adsorbed strongly on the surface of SWNT when the samples were incubated in the Hfg solutions for 10 min. The dependence of adsorption on the concentration of fibrinogen was also investigated and it was found that adsorption increased with increasing concentration. In order to further explore the adsorption of fibrinogen on SWNT surface, NEXAFS spectra were obtained at the N K-edge and the C K-edge. The results confirmed the conclusion regarding the dependence of adsorption on fibrinogen concentration. It is demonstrated that, due to its high sensitivity to the surface elements, NEXAFS spectroscopy is a powerful tool to investigate the adsorption of fibrinogen on SWNT films.

Adsorption↗
PubMed2006

Using single-walled carbon nanotubes nonwoven films as scaffolds to enhance long-term cell proliferation in vitro.

Carbon nanotubes have attracted intensive interests in biomedical research in recent years. In this study, a novel type of carbon nanotubes material so called nonwoven single-walled carbon nanotubes (SWNTs) with nanotopographic structure and macroscopic volume was used as cell growing scaffold. The morphology and surface chemistry of nonwoven SWNTs were observed and characterized through scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The cells were cultivated in nonwoven SWNTs and in other types of substrate as control. The cells growth behaviors including adhesion, proliferation, and cytoskeletal development was investigated by using cell viability assay and confocal observation. The experimental results indicated that nonwoven SWNTs exhibited significant enhancement to the cells adhesion and proliferation in at least 3 weeks. Numerous and highly organized cytoskeletal structures were observed when the cells were cultured in nonwoven SWNTs. Furthermore, an obvious promotional influence of the cells cultivated in nonwoven SWNTs scaffold upon the proliferation of those growing in the other kind of substrate through cell-cell communication had been found. The results obtained in this work are of significance to in vitro cell amplification in large scale, tissue regeneration, or guided repair, as well as biomedical device application.

3T3-L1 Cells↗
PubMed2006

[Fluid management in orthotopic liver transplantation].

OBJECTIVE: To investigate the influential factors of fluid management during orthotopic liver transplantation surgery. METHODS: Ninety-six patients scheduled for orthotopic liver transplantation were divided into two groups according to the liver function: the decompensatory group (Child-Pugh score C, n=50) and the compensatory group (Child-Pugh score A or B, n=46). According to the intraoperative bleeding amount, the compensatory group was further divided into subgroup A (< 2,000 ml) and subgroup B (> or = 2,000 ml). Plasma albumin concentration and the parameters of blood coagulation were measured before and after the surgery. The intraoperative bleeding amount and the amount of the blood products infused were recorded. RESULTS: Before the surgery, prothrombin time (PT) and activated partial thromboplastin time (APTT) were significantly longer in decompensatory group than in compensatory group (both P<0.05); blood platelets (PLT) and fibrinogen were significantly lower in decompensatory group than in compensatory group (both P<0.05). After the surgery, there were no significant differences in PT, APTT, PLT, and fibrinogen between the two groups (all P>0.05). The amounts of the blood products infused intraoperatively in subgroup A were significantly lower than those in the decompensatory group (all P<0.05). There was no significant difference in the amount of the infused blood products between the subgroup B and decompensatory group (all P>0.05). CONCLUSION: During orthotopic liver transplantation surgery, patients with decompensatory liver function, or those who suffered large amounts of intraoperative bleeding, need infusion of larger amount of blood products.

Adolescent↗
PubMed2006

[Village resident nourishment of Hebei investigates with health condition].

OBJECTIVE: To study the changes of the food and nutrients intake and health trends in rural population of Hebei Province since 1992 with the society economy development rapidly. METHODS: Using the multi-stage cluster random sampling method, investigating the body high, weight, blood pressure, Haemoglobin, blood lipids, blood glucose, of 11627 population from 2700 households, and the food consumption and nutrients intakes of 1080 households, to analyses and assess the dietary pattern and mortality of chronic diseases. RESULTS: The results showed that plant food is main food consumption pattern and changed remarkably since the 1992. Although the meat, egg, milk and beat consumption was more than 1992 their intakes are insufficient. The fat food and the salt intakes increased while CA and VA intakes were very insufficient. Weighs values in the school children aged 7-17 were significantly higher than those in 1992. The prevalence of overweight, obese, high blood pressure, diabetes, abnormal blood sugar were 30.4%, 13.4%, 25.9%, 1.8%, 0.98%, respectively in adults aged over 18. The rate of abnormal blood lipid 25.0%, high TG, TC, verge TC, low HDL-C were 15.3%, 3.2%, 3.5%, 10.8%. The standardized prevalence of anemia 8.7% and 16% for preschool children and younger woman respectively. CONCLUSION: The prevalence of overweight, obese, hypertension and abnormal blood lipids in adult population of rural Hebei Province were higher than the average levels in whole country. Sufficient attention should be paid to nutrition diet, heath and some chronic diseases related to nutrition in rural residents, the dietary guidance and nutrition interference need to strengthen and ensure people health.

Adolescent↗