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Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (34S) than in the light one (32S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes. Provided with the same octatomic ring structure, the cyclo-34S8 molecules form stronger S-S bonds than cyclo-32S8 and are more prone to react with Li. The soluble Li polysulfides generated by the Li-34S conversion reaction show a stronger cation-solvent interaction yet a weaker cation-anion interaction than the 32S-based counterparts, which facilitates quick solvation of polysulfides yet hinders their migration from the cathode to the anode. Consequently, the Li-34S cell shows improved cathode reaction kinetics at the solid-liquid interface and inhibited shuttle of polysulfides through the electrolyte so that it demonstrates better cycling performance than the Li-32S cell. Based on the varied shuttle kinetics of the isotopic-S-based polysulfides, an electrochemical separation method for 34S/32S isotope is proposed, which enables a notably higher separation factor than the conventional separation methods via chemical exchange or distillation and brings opportunities to low-cost manufacture, utilization, and research of heavy chalcogen isotopes.
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Graphite has been serving as the key anode material of rechargeable Li-ion batteries, yet is difficultly charged within a quarter hour while maintaining stable electrochemistry. In addition to a defective edge structure that prevents fast Li-ion entry, the high-rate performance of graphite could be hampered by co-intercalation and parasitic reduction of solvent molecules at anode/electrolyte interface. Conventional surface modification by pitch-derived carbon barely isolates the solvent and electrons, and usually lead to inadequate rate capability to meet practical fast-charge requirements. Here we show that, by applying a MoOx-MoNx layer onto graphite surface, the interface allows fast Li-ion diffusion yet blocks solvent access and electron leakage. By regulating interfacial mass and charge transfer, the modified graphite anode delivers a reversible capacity of 340.3â mAh g-1 after 4000â cycles at 6â C, showing promises in building 10-min-rechargeable batteries with a long operation life.
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The widespread use of surfactants raise challenges to biological wastewater treatment. Anaerobic ammonium oxidation (anammox) process has the potential to treat wastewater containing anionic surfactants, but the response of anammox consortia at the molecular level under long-term exposure is unclear. Using high-throughput sequencing and gene quantification, combined with molecular docking, the effect of sodium dodecyl sulfonate (SDS) on anammox consortia were investigated. Levels of reactive oxygen species (ROS) might be lower than the threshold of oxidative damage, while the increase of lactate dehydrogenase (LDH) represented the cell membrane damage. Decreased abundance of functional genes (hdh, hzsA and nirS) indicated the decrease of the anammox bacterial abundance. Trace amounts of N-acyl homoserine lactone (AHL, C6-HSL, C8-HSL and C12-HSL) contained in influent could induce endogenous quorum sensing (QS), which could regulate the correlation between functional bacteria to optimize the microbial community and strengthen the resistance of anammox consortia to SDS. In addition, the proliferation of disinfectant resistance genes might increase the environmental pathogenicity of sewage discharge. This work highlights the potential response mechanism of anammox consortium to surfactants and provides a universal microbial-friendly bioenhancement strategy based on QS.
Assuntos
Percepção de Quorum , Tensoativos , Eliminação de Resíduos Líquidos , Tensoativos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Oxirredução , Anaerobiose , Compostos de Amônio/metabolismo , Simulação de Acoplamento Molecular , Consórcios Microbianos/fisiologiaRESUMO
Single-crystalline nickel-rich layered oxides are promising cathode materials for building high-energy lithium-ion batteries because of alleviated particle cracking and irreversible phase transitions upon cycling, compared with their polycrystalline counterparts. Under a high state of charge, parasitic reactions tend to occur at the cathode-electrolyte interface, which could result in sluggish Li-ion diffusion kinetics and quickly faded electrochemical performance of cathodes. In this work, a concentration-gradient niobium-doping strategy was applied to modify the single-crystal LiNi0.83Co0.12Mn0.05O2 cathode, with Nb concentration decreasing linearly from the surface to the core of the particle. As a result, the Nb-rich surface functions as an electrochemically active protective layer against electrolyte corrosion and transition metal dissolution, while the Nb-deficient core contributes to a higher capacity. The linear concentration gradient also minimizes structural transition from the surface to the core and helps to maintain structural integrity during repeated Li (de)intercalation. In addition, Nb-doping also assists to alleviate Li+/Ni2+ mixing and increases the interlayer distance to enable faster Li-ion diffusion kinetics. By taking these advantages, the Nb-doped cathode materials (containing 1.0 atom% Nb) demonstrate a high reversible capacity, a high capacity retention, and improved rate capabilities. This work provides a general and facile approach to improve the storage performance of layered-oxide cathode materials by rationally tuning the bulk structure and interface with the electrolyte.
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OBJECTIVE: To explore the spatial and temporal characteristics of measles patients younger than 1 year old in Shandong province. METHODS: A total of 5309 cases of measles, whose patients were younger than 1 year old in Shandong province between year 1999 and 2008 were collected. The epidemic features of measles were described, and the annual infant incidence was calculated. Software ArcGIS9.3 was applied to draw the spatial map of the disease, and the software GeoDa0.95i-beta was adopted to analyze the spatial autocorrelation. RESULTS: The incidence among infants younger than 1 year old reported in Shandong province rose from 23.45/100 000 (206 cases) in 1999 to 269.60/100 000 (2791 cases) in 2008.5309 cases covered all month-aged infants under 1 year old, except 12 months old. Most patients (3494 cases) aged between 6 - 9 months old; especially the infants around 8 months old, accounting for 20.7% (1100/5309). The epidemic peak was between March and May, accounting for 45.5% (2414/5309). The spatial and temporal distribution features showed an up and down temporal trend and an increase from east to west in spatial trend. The global Moran's I values of measles incidence among infants in Shandong province were 0.346, 0.150, 0.396, 0.213, 0.477, 0.354 and 0.331 in year 1999, 2001 - 2002, 2005 - 2008 (P < 0.01) and 0.076 in year 2004 (P < 0.05). The local spatial autocorrelation analysis showed that southwest and northwest districts of Shandong were highly clustered districts of measles. CONCLUSION: In Shandong, the measles incidence among infants younger than 1 year old rose obviously; especially the infants aged between 6-9 months age. The epidemic peak was between March and May. A positive spatial correlation was found, the disease showed a distinct regional distribution feature, and a cluster district was found.
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Geografia , Sarampo/epidemiologia , China/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Conglomerados Espaço-TemporaisRESUMO
Icaritin has potential anticancer effects on various cancers, including multiple myeloma (MM). Recent studies claim that Icaritin can regulate the expression of noncoding RNAs (ncRNAs) in cancer development. This study aimed to investigate the role of circular RNA_0000190 (circ_0000190) and functional mechanism in Icaritin-treated MM. The expression of circ_0000190 and miR-301a was detected by quantitative real-time polymerase chain reaction. Cell cycle, apoptosis, migration, and invasion were investigated using flow cytometry assay, and transwell assay, respectively. The expression of BAX, BCL2, MMP2, and CCND1 was detected by western blot. The predicted target relationship between circ_0000190 and miR-301a was validated by dual-luciferase reporter assay and RNA immunoprecipitation assay. The activation of JAK1/STAT3 pathway was examined using western blot. Circ_0000190 was strikingly downregulated in MM specimens and cell lines, and Icaritin promoted the expression of circ_0000190. In function, circ_0000190 overexpression promoted MM cell cycle arrest and apoptosis but restrained the ability of migration and invasion. Icaritin blocked the development of MM by increasing circ_0000190 expression. MiR-301a was identified as a target of circ_0000190, and miR-301a reintroduction largely abolished the effects of circ_0000190 overexpression. The activation of JAK1/STAT3 pathway was promoted by miR-301a restoration. Icaritin played anticancer effects in MM partly by enhancing the expression of circ_0000190 and regulating the circ_0000190/miR-301a pathway. This study enhanced the understanding of the mechanism of Icaritin associated with circRNAs in MM.
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MicroRNAs , Mieloma Múltiplo , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Flavonoides , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , RNA Circular/genéticaRESUMO
To investigate the associations between dietary fatty acids and cholesterol consumption and stomach cancer (SC), we analyzed data from a population-based case-control study with a total of 1900 SC cases and 6532 controls. Dietary data and other risk or protective factors were collected by face-to-face interviews in Jiangsu Province, China, from 2003 to 2010. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multiple unconditional logistic regression models and an energy-adjusted method. The joint associations between dietary factors and known risk factors on SC were examined. We observed positive associations between dietary saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and total cholesterol and the development of SC, comparing the highest versus lowest quarters. Increased intakes of dietary SFAs (p-trend = 0.005; aOR, 1.11; 95% CI, 1.01-1.22 with a 7 g/day increase as a continuous variable) and total cholesterol (p-trend < 0.001; aOR, 1.13; 95% CI, 1.06-1.22 with a 250 mg/day increase as a continuous variable) were monotonically associated with elevated odds of developing SC. Our results indicate that dietary SFAs, MUFAs, and total cholesterol are associated with stomach cancer, which might provide a potential dietary intervention for stomach cancer prevention.
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Colesterol na Dieta/efeitos adversos , Dieta/efeitos adversos , Ácidos Graxos/efeitos adversos , Neoplasias Gástricas/epidemiologia , Idoso , Estudos de Casos e Controles , China/epidemiologia , Colesterol na Dieta/administração & dosagem , Ácidos Graxos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Recomendações Nutricionais , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/prevenção & controleAssuntos
Discotomia Percutânea , Deslocamento do Disco Intervertebral , Estenose Espinal , Idoso , Endoscopia , Humanos , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Estenose Espinal/complicações , Estenose Espinal/cirurgia , Resultado do TratamentoRESUMO
Multigene-armed oncolytic adenoviruses are capable of efficiently generating a productive antitumor immune response. The chemokine (C-C motif) ligand 21 (CCL21) binds to CCR7 on naïve T cells and dendritic cells (DCs) to promote their chemoattraction to the tumor and resultant antitumor activity. Interleukin 21 (IL21) promotes survival of naïve T cells while maintaining their CCR7 surface expression, which increases their capacity to transmigrate in response to CCL21 chemoattraction. IL21 is also involved in NK cell differentiation and B cell activation and proliferation. The generation of effective antitumor immune responses is a complex process dependent upon coordinated interactions of various subsets of effector cells. Using the AdEasy system, we aimed to construct an oncolytic adenovirus co-expressing CCL21 and IL21 that could selectively replicate in TERTp-positive tumor cells (Ad-CCL21-IL21 virus). The E1A promoter of these oncolytic adenoviruses was replaced by telomerase reverse transcriptase promoter (TERTp). Ad-CCL21-IL21 was constructed from three plasmids, pGTE-IL21, pShuttle-CMV-CCL21 and AdEasy-1 and was homologously recombined and propagated in the Escherichia coli strain BJ5183 and the packaging cell line HEK-293, respectively. Our results showed that our targeted and armed oncolytic adenoviruses Ad-CCL21-IL21 can induce apoptosis in TERTp-positive tumor cells to give rise to viral propagation, in a dose-dependent manner. Importantly, we confirm that these modified oncolytic adenoviruses do not replicate efficiently in normal cells even under high viral loads. Additionally, we investigate the role of Ad-CCL21-IL21 in inducing antitumor activity and tumor specific cytotoxicity of CTLs in vitro. This study suggests that Ad-CCL21-IL21 is a promising targeted tumor-specific oncolytic adenovirus.
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Adenoviridae/genética , Proteínas E1A de Adenovirus/genética , Quimiocina CCL21/genética , Interleucinas/genética , Vírus Oncolíticos/genética , Telomerase/genética , Adenoviridae/imunologia , Proteínas E1A de Adenovirus/imunologia , Células CACO-2 , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quimiocina CCL21/imunologia , Técnicas de Cocultura , Células Epiteliais/citologia , Células Epiteliais/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Células HEK293 , Células HT29 , Células HeLa , Recombinação Homóloga , Humanos , Interleucinas/imunologia , Masculino , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/imunologia , Plasmídeos/química , Plasmídeos/imunologia , Próstata/citologia , Próstata/imunologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Células THP-1 , Telomerase/imunologiaRESUMO
Conditionally replicating adenoviruses (CRAds) selectively replicate in cancer cells and induce cell lysis, which represents a potential platform for cancer immunotherapy. The chemokine CCL20 exerts antitumor activity via chemoattraction of immature dendritic cells (DCs) and lymphocytes. However, the activation and maturation status of DCs is a limiting factor in the DCs -based immunity response. CD40L induces the phenotypic maturation of DCs, mediates DCs cytokine secretion, and increases the expression of FasL, which mediates apoptosis. We constructed a CCL20/CD40L co-expression CRAds (Ad-CCL20-CD40L) based on the AdEasy system. Ad-CCL20-CD40L was constructed from three plasmids, pGTE-CD40L, pShuttle-CMV-CCL20 and AdEasy-1, and was homologously recombined and propagated in the Escherichia coli strain BJ5183 and the packaging cell line HEK-293, respectively. Ad-CCL20-CD40L selectively replicates in TERT-positive tumor cells because the pGTE-CD40L plasmid contains the telomerase reverse transcriptase promoter (TERTp). Our results showed that Ad-CCL20-CD40L induced oncolytic effects and tumor-specific cytotoxicity of cytotoxic T lymphocytes (CTLs) in vitro. This study suggests that Ad-CCL20-CD40L can induce the antitumor immune response and that this platform can be modified to generate novel CRAds with other transgenes.
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Adenoviridae/genética , Ligante de CD40/genética , Quimiocina CCL20/genética , Vírus Oncolíticos/genética , Telomerase/genética , Linhagem Celular Tumoral , Terapia Genética , Humanos , Neoplasias/terapia , Linfócitos T Citotóxicos/imunologiaRESUMO
OBJECTIVES: Renal transplantation is the preferred method for most patients with end-stage renal disease, however, acute renal allograft rejection is still a major risk factor for recipients leading to renal injury. To improve the early diagnosis and treatment of acute rejection, study on the molecular mechanism of it is urgent. METHODS: MicroRNA (miRNA) expression profile and mRNA expression profile of acute renal allograft rejection and well-functioning allograft downloaded from ArrayExpress database were applied to identify differentially expressed (DE) miRNAs and DE mRNAs. DE miRNAs targets were predicted by combining five algorithm. By overlapping the DE mRNAs and DE miRNAs targets, common genes were obtained. Differentially co-expressed genes (DCGs) were identified by differential co-expression profile (DCp) and differential co-expression enrichment (DCe) methods in Differentially Co-expressed Genes and Links (DCGL) package. Then, co-expression network of DCGs and the cluster analysis were performed. Functional enrichment analysis for DCGs was undergone. RESULTS: A total of 1270 miRNA targets were predicted and 698 DE mRNAs were obtained. While overlapping miRNA targets and DE mRNAs, 59 common genes were gained. We obtained 103 DCGs and 5 transcription factors (TFs) based on regulatory impact factors (RIF), then built the regulation network of miRNA targets and DE mRNAs. By clustering the co-expression network, 5 modules were obtained. Thereinto, module 1 had the highest degree and module 2 showed the most number of DCGs and common genes. TF CEBPB and several common genes, such as RXRA, BASP1 and AKAP10, were mapped on the co-expression network. C1R showed the highest degree in the network. These genes might be associated with human acute renal allograft rejection. CONCLUSIONS: We conducted biological analysis on integration of DE mRNA and DE miRNA in acute renal allograft rejection, displayed gene expression patterns and screened out genes and TFs that may be related to acute renal allograft rejection.