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Both herbivory and jasmonic acid (JA) activate the biosynthesis of defensive metabolites in maize, but the mechanism underlying this remains unclear. We generated maize mutants in which ZmMYC2a and ZmMYC2b, two transcription factor genes important in JA signaling, were individually or both knocked out. Genetic and biochemical analyses were used to elucidate the functions of ZmMYC2 proteins in the maize response to simulated herbivory and JA. Compared with the wild-type (WT) maize, the double mutant myc2ab was highly susceptible to insects, and the levels of benzoxazinoids and volatile terpenes, and the levels of their biosynthesis gene transcripts, were much lower in the mutants than in the WT maize after simulated insect feeding or JA treatment. Moreover, ZmMYC2a and ZmMYC2b played a redundant role in maize resistance to insects and JA signaling. Transcriptome and Cleavage Under Targets and Tagmentation-Sequencing (CUTTag-Seq) analysis indicated that ZmMYC2s physically targeted 60% of the JA-responsive genes, even though only 33% of these genes were transcriptionally ZmMYC2-dependent. Importantly, CUTTag-Seq and dual luciferase assays revealed that ZmMYC2s transactivate the benzoxazinoid and volatile terpene biosynthesis genes IGPS1/3, BX10/11/12/14, and TPS10/2/3/4/5/8 by directly binding to their promoters. Furthermore, several transcription factors physically targeted by ZmMYC2s were identified, and these are likely to function in the regulation of benzoxazinoid biosynthesis. This work reveals the transcriptional regulatory landscapes of both JA signaling and ZmMYC2s in maize and provides comprehensive mechanistic insight into how JA signaling modulates defenses in maize responses to herbivory through ZmMYC2s. This article is protected by copyright. All rights reserved.

As an alternative mechanism for cap-dependent (m7GpppN) translation, internal ribosome entry site (IRES)-dependent translation has been observed in the 5' untranslated regions (5' UTR) and coding regions of a number of viral and eukaryotic mRNAs. In this study, a series of 5' terminal truncated structural protein genes that were fused with GFP was used to screen for potential IRESs, and IRESs were identified using a bicistronic luciferase vector or GFP expression vector possessing a hairpin structure. Our results revealed that a putative IRES was located between nt 1982 and 2281 in the VP3 coding region of the human rhinovirus 16 (HRV16) genomes. We also demonstrated that effective IRES-initiated protein expression in vitro did not occur through splicing sites or cryptic promoters. We confirmed that thapsigargin (TG), an inducer of endoplasmic reticulum stress (ERS), facilitated increased IRES activity in a dose-dependent manner. Additionally, the secondary structure of the IRES was predicted online using the RNAfold web server.

Identification of different mitochondrial reactive oxygen species (ROS) simultaneously in living cells is vital for understanding the critical roles of different ROS in biological processes. To date, it remains a great challenge to develop ROS probes for direct and simultaneous identification of multiple ROS with high specificity. Herein, we report a SERS-borrowing-strategy-based nanoprobe (Au@Pt core-shell nanoparticles) for simultaneous and direct identification of different ROS by their distinct Raman fingerprints. Isotope substitution experiments and DFT calculations confirmed the ability of Au@Pt nanoprobe to capture and identify different mitochondrial ROS (i.e. ⋅OOH, H

Introduction COVID-19 has spread rapidly worldwide and has been declared a pandemic. Objectives To delineate clinical features of COVID-19 patients with different severities and prognoses and clarify the risk factors for disease progression and death at an early stage. Methods Medical history, laboratory findings, treatment and outcome data from 214 hospitalised patients with COVID-19 pneumonia admitted to Eastern Campus of Renmin Hospital, Wuhan University in China were collected from 30 January 2020 to 20 February 2020, and risk factors associated with clinical deterioration and death were analysed. The final date of follow-up was 21 March 2020. Results Age, comorbidities, higher neutrophil cell counts, lower lymphocyte counts and subsets, impairment of liver, renal, heart, coagulation systems, systematic inflammation and clinical scores at admission were significantly associated with disease severity. Ten (16.1%) moderate and 45 (47.9%) severe patients experienced deterioration after admission, and median time from illness onset to clinical deterioration was 14.7 (IQR 11.3-18.5) and 14.5 days (IQR 11.8-20.0), respectively. Multivariate analysis showed increased Hazards Ratio of disease progression associated with older age, lymphocyte count 9.5 mmol/L, lactate dehydrogenase >250 U/L and procalcitonin >0.1 ng/mL at admission. These factors were also associated with the risk of death except for BUN. Prediction models in terms of nomogram for clinical deterioration and death were established to illustrate the probability. Conclusions These findings provide insights for early detection and management of patients at risk of disease progression or even death, especially older patients and those with comorbidities.

Objective Acute bilirubin encephalopathy (ABE) remains one of the important causes of neonatal mortality and child disability, early identification, and intervention which could improve outcomes. The purpose of this study was to evaluate early predictors of adverse outcomes in infants with ABE. Methods Newborns of gestational age ≥ 35 weeks and diagnosed with ABE were included in the study. Bilirubin‐induced neurological dysfunction (BIND) score, total serum bilirubin (TSB) peak value, and serum albumin levels were determined. Adverse outcomes were defined as death or survival with auditory dysfunction and/or cerebral palsy. Results Eighty‐two infants were eligible for recruitment in the study. The outcome data from 76 ABE infants (92%) were used for analysis, of which 25 infants got adverse outcomes and 51 live a normal life. Univariate analysis for BIND score, TSB peak value, bilirubin–albumin ratio (B/A), albumin level, abnormal AABR, and neonatal sepsis was performed to elucidate the association with adverse outcomes. Bivariate logistic regression analysis showed B/A (OR 10.48, 95%CI: 1.55–70.81, P = 0.02) and BIND score (OR 3.68, 95%CI: 1.39–9.72, P = 0.01) were correlated with adverse outcomes. ROC curve analysis showed that B/A (≥8.9 mg/g), BIND score (≥6) could predict adverse outcomes of ABE separately; B/A in conjunction with BIND score could increase prediction sensitivity to 100%. Interpretation Both B/A and BIND score can be used to predict adverse outcomes of ABE, and the combination of the two parameters can increase prediction sensitivity significantly.

Preterm birth and associated brain injury are the primary cause of cerebral palsy and developmental disabilities and are among the most serious global health issues that modern society faces. Current therapy for infants suffering from premature brain injury is still mainly supportive, and there are no effective treatments. Thus there is a pressing need for comparative and translational studies on how to reduce brain injury and to increase regeneration and brain repair in preterm infants. There is strong supporting evidence for the use of umbilical cord blood (UCB)-derived stem cell therapy for treating preterm brain injury and neurological sequelae. UCB-derived stem cell therapy is effective in many animal models and has been shown to be feasible in clinical trials. Most of these therapies are still experimental, however. In this review, we focus on recent advances on the efficacy of UCB-derived stem cell therapy in preterm infants with brain injury, and discuss the potential mechanisms behind their therapeutic effects as well as application strategies for future preclinical and clinical trials.

Background Multiple sclerosis is characterized by demyelination/remyelination, neuroinflammation, and neurodegeneration. Cuprizone (CPZ)-induced toxic demyelination is an experimental animal model commonly used to study demyelination and remyelination in the central nervous system. Fasudil is one of the most thoroughly studied Rho kinase inhibitors. Methods Following CPZ exposure, the degree of demyelination in the brain of male C57BL/6 mice was assessed by Luxol fast blue, Black Gold II, myelin basic protein immunofluorescent staining, and Western blot. The effect of Fasudil on behavioral change was determined using elevated plus maze test and pole test. The possible mechanisms of Fasudil action were examined by immunohistochemistry, flow cytometry, ELISA, and dot blot. Results Fasudil improved behavioral abnormalities, inhibited microglia-mediated neuroinflammation, and promoted astrocyte-derived nerve growth factor and ciliary neurotrophic factor, which should contribute to protection and regeneration of oligodendrocytes. In addition, Fasudil inhibited the production of myelin oligodendrocyte glycoprotein antibody and the infiltration of peripheral CD4+ T cells and CD68+ macrophages, which appears to be related to the integrity of the blood-brain barrier. Conclusion These results provide evidence for the therapeutic potential of Fasudil in CPZ-induced demyelination. However, how Fasudil acts on microglia, astrocytes, and immune cells remains to be further explored.

Neuromorphic computing using spike‐based learning has broad prospects in reducing computing power. Memristive neurons composed with two locally active memristors have been used to mimic the dynamical behaviors of biological neurons. Herein, the dynamic operating conditions of NbO2‐based memristive neurons and their transformation boundaries between the spiking and the bursting are comprehensively investigated. Furthermore, the underlying mechanism of bursting is analyzed, and the controllability of the number of spikes during each burst period is demonstrated. Finally, pattern classification and information transmitting in a perceptron neural network by using the number of spikes per bursting period to encode information is proposed. The results show a promising approach for the practical implementation of neuristor in spiking neural networks.

Background Glucocorticoid (GC) insensitivity is an important feature of severe and fatal asthma. Oxidative stress can induce phosphoinositide-3-kinase (PI3K) activation, contributing to the development of GC insensitivity in chronic airway diseases. However, the underlying molecular mechanism of PI3K in the pathogenesis of severe asthma remains unknown. Methods We isolated peripheral blood mononuclear cells (PBMCs) from 34 participants (12 patients with mild/moderate asthma, 10 patients with severe asthma, and 12 control subjects). H2O2 was used to stimulate the human macrophage line U937 to mimic the oxidative stress status in severe asthma. The ability of candidate compounds, namely, azithromycin, PI3K inhibitors (BEZ235 and LY294002) and a p38 MAPK inhibitor (BIRB796), to ameliorate GC insensitivity in severe asthma was evaluated. Results PBMCs from patients with severe asthma exhibited dose-dependent and time-dependent GC insensitivity, which correlated with reduced activity of histone deacetylase 2 (HDAC2) (p

Ionic current rectification (ICR) based nanopipettes allow accurate monitoring of cellular behavior in single living cells. Herein, we proposed a 30 nm nanopipette functionalized with G-quadruplex DNAzyme as an efficient biomimetic recognizer for ROS generation at subcellular level via the changes of current-voltage relationship. Taking advantages of the ultra-small tip, the nanopipette could penetrate into a single living cell repeatedly or keep measuring for a long time without compromising the cellular functions. Coupled with precision nanopositioning system, generation of ROS in mitochondria in response to cell inflammation was determined with high spatial resolution. Meanwhile, the changes of aerobic metabolism in different cell lines under drug-induced oxidative stress were monitored continuously. We believe that the ICR-nanopipette could be developed as a powerful approach for the study of cellular activities via electrochemical imaging in living cells.

Atmospheric CO2 levels are rapidly increasing due to human activities. However, the effects of elevated CO2 (ECO2) on plant defense against insects and the underlying mechanisms remain poorly understood. Here we show that ECO2 increased the photosynthetic rates and the biomass of tobacco and rice plants, and the chewing lepidopteran insects Spodoptera litura and Mythimna separata gained less and more mass on tobacco and rice plants, respectively. Consistently, under ECO2, the levels of jasmonic acid (JA), the main phytohormone controlling plant defense against these lepidopteran insects, as well as the main defense-related metabolites, were increased and decreased in insect-damaged tobacco and rice plants. Importantly, bioassays and quantification of defense-related metabolites in tobacco and rice silenced in JA biosynthesis and perception indicate that ECO2 changes plant resistance mainly by affecting the JA pathway. We further demonstrate that the defensive metabolites, but not total N or protein, are the main factors contributing to the altered defense levels under ECO2. This study illustrates that ECO2 changes the interplay between plants and insects, and we propose that crops should be studied for their resistance to the major pests under ECO2 to predict the impact of ECO2 on future agroecosystems.

Background and Purpose Non-alcoholic steatohepatitis (NASH) is characterized by excessive intracellular lipid accumulation, inflammation and hepatic insulin resistance. As the incidence of NASH is increasing worldwide, there is an urgent need to find novel interventional approaches. The pro-inflammatory cytokine IL-1β, generated and released from Kupffer cells, is considered to initiate the development of NASH. AS-1, a synthetic low-molecule mimetic of myeloid differentiation primary response gene 88 (MyD88), disrupts the interaction between the IL-1 receptor and MyD88. Here, we investigated whether AS-1 could attenuate the pathogenesis of NASH with an emphasis on hepatic insulin resistance. Experimental Approach Eight-week-old db/db mice were fed a control diet or a methionine- and choline-deficient (MCD) diet. AS-1 (50 mg·kg−1) or vehicle was administered i.p. Key Results AS-1 administration significantly ameliorated NASH as evidenced by alanine aminotransferase levels and CD68 levels in livers of MCD-fed mice. AS-1 inhibited the MCD diet-induced activation of caspase 1 and the NLRP3-ASC inflammasome, and also reduced the enhanced levels of ROS, malondialdehyde, 3-nitrotyrosine, NADPH oxidase complex and CYP reductase-associated cytochrome p450 2E1 (CYP2E1) expression in the liver. In addition, AS-1 decreased ROS, inflammasome activation and IL-1β production in free fatty acid-LPS-treated Kupffer cells. Finally, pretreatment with AS-1 significantly ameliorated gluconeogenesis and insulin desensitization induced by IL-1β, probably by blocking the interaction between MyD88 and the IL-1 receptor. Conclusions and Implications Our results indicate that AS-1 can ameliorate NASH and hepatic insulin resistance and could be considered as a potential strategy for the prevention and treatment of NASH.

Objectives To assess the prevalence and potential risk factors of latent tuberculosis infection (LTBI) in Chinese patients with inflammatory bowel disease (IBD) and to evaluate the role of chest computed tomography (CT) in the screening of LTBI. Methods A single-center retrospective study was conducted and all IBD patients who had been screened for LTBI by T-SPOT.TB between December 2011 and January 2016 were enrolled in the study. Both inpatient and outpatient records were collected and comprehensively reviewed. Results Altogether 534 IBD patients were included. The positivity rate of T-SPOT.TB was 18.0% overall, 31.9% in IBD unclassified, 22.5% in ulcerative colitis and 13.0% in Crohn's disease patients, respectively. Age, history of TB and the administration of immunosuppressants were significantly associated with T-SPOT.TB positivity. Among 123 patients who underwent serial testing, the conversion and reversion rate of T-SPOT.TB was 10.2% and 42.9%, respectively. Furthermore, 102 of 447 (22.8%) patients who underwent chest computed tomography (CT) were found with abnormal CT findings suggestive of LTBI. The concordance rate was 75% between the T-SPOT.TB and chest CT with a kappa value of 0.25 (95% CI 0.15–0.35). Conclusions The prevalence of LTBI in IBD patients is high in China. Chest CT is recommended as an alternative to IGRA for screening LTBI of IBD patients before commencing immunosuppressive therapy in high-prevalence regions.

A bipolar host material, 2,4,6-tris(3-(carbazol-9-yl)phenyl)-triazine (TCPZ), was synthesized according to reported method. Due to the higher triplet energy compared to green and red phosphors, TCPZ is suitable to host them in phosphorescent organic light-emitting diodes (PhOLEDs). Although the triplet of TCPZ is slightly lower than a common blue phosphor, good blue PhOLEDs using TCPZ as the host were successfully demonstrated in this work. By low temperature emission measurement, it was found that the energy splitting between the singlet and triplet of TCPZ is as small as 0.24 eV. Therefore, thermal activated energy transfer from triplet to singlet in the host TCPZ is expected to occur, which can be afterwards efficiently transferred to the blue phosphor, hence enabling it to host blue phosphor. As a result, TCPZ can be used as host for phosphors in panchromatic range. Additionally, single-carrier devices clearly prove its good bipolar transport feature, beneficial to device performance. By using TCPZ as a host, high performance deep-red, green and blue PhOLEDs have been achieved, with maximum efficiencies of 9.3 cd·A−1 (13.2%), 81.3 cd·A−1 (23.1%) and 17.03 cd·A−1 (10.4%), respectively.

Fluorenes have been synthesized through an efficient novel Pd-catalyzed tandem cross-coupling reaction; these substrates are fascinating building blocks found in organic photoelectric materials. The position of the substituent on fluorenes could be conveniently tuned by changing the halogen in the ortho-halobenzyl bromide substrates when coupled with various arylboronic acids. This newly developed synthetic approach could achieve the potential diversity in fluorene-based molecular architectures.

Background Eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) is an important factor regulating protein translation. It also impacts proliferation, apoptosis, invasion, and the cell cycle of cancer cells. The aim of this study was to investigate the relationship between 4E-BP1 and human immune status, recognizing immunomodulatory molecules involved in the overexpression of 4E-BP1. Methods A lentivirus expression system was used to overexpress 4E-BP1 in the H1299 cell line. Western blot was performed to investigate the expression level of 4E-BP1 and P-4E-BP1, and quantitative polymerase chain reaction was used to quantify gene expression of immunomodulatory molecules. Results The expression level of 4E-BP1 increased significantly after lentivirus infection (P < 0.05). Overexpression of 4E-BP1 upregulated the expression of interleukin (IL)-1β (P < 0.05), IL-5 (P < 0.001), IL-23 (P < 0.001), macrophage inflammatory protein-1β (P < 0.001), Eota-3 (P < 0.05), and MCP-4 (P < 0.05). Most of the increases were observed at the seventh day. The variation trend of IL-10, cell division cycle protein 2, proliferating cell nuclear antigen, and phosphatase and tensin homolog was not clear. Conclusion Overexpression of 4E-BP1 altered immune status by upregulating the expression of a series of immunomodulatory molecules, indicating that 4E-BP1 could serve as a potential therapeutic target against cancer.

Four new polyhydroxylated steroids, 1-4, and the racemic form of cyclopentenone 9, together with four known steroids, 5-8, one known cyclopentenone derivative, 10, and one known butenolide derivative, 11, were isolated from the soft coral Sinularia acuta collected from Weizhou Island of Guangxi Province, P. R. China. Their structures were elucidated on the basis of spectroscopic analyses and by comparison of the corresponding data with those previously reported. The cytotoxicities of the isolates 1-11 in vitro against the selected tumor cell lines HL-60, HeLa, and K562 were evaluated. Compounds 2 and 5 showed potent cytotoxicities against HL-60 cell lines with IC50 values of 7.3 and 9.9 μM, respectively. Compounds 5 and 6 showed moderate activities against K562 cell lines with IC50 values of 10.9 and 11.7 μM, respectively, while compounds 1, 2, and 6 showed weak activities against HeLa cell lines with respective IC50 values of 44.8, 27.1, and 18.2 μM. This is the first report on chemical and bioactivity research of S. acuta.

Stress granules (SGs) and processing bodies (PBs) comprise the main types of cytoplasmic RNA foci during stress. Our previous data indicate that knockdown of human Tudor staphylococcal nuclease (Tudor-SN) affects the aggregation of SGs. However, the precise molecular mechanism has not been determined fully. In the present study, we demonstrate that Tudor-SN binds and colocalizes with many core components of SGs, such as poly(A)(+) mRNA binding protein 1, T-cell internal antigen-1-related protein and poly(A)(+) mRNA, and SG/PB sharing proteins Argonaute 1/2, but not PB core proteins, such as decapping enzyme 1 a/b, confirming that Tudor-SN is an SG-specific protein. We also demonstrate that the Tudor-SN granule actively communicates with the nuclear and cytosolic pool under stress conditions. Tudor-SN can regulate the aggregation dynamics of poly(A)(+) mRNA-containing SGs and selectively stabilize the SG-associated mRNA during cellular stress.

A palladium-catalyzed desulfitative arylation reaction of 5-alkoxy-3,4-dibromo-2(5H)-furanones to provide 5-alkoxy-4-aryl-3-bromo-2(5H)-furanones is reported. This reaction has a high reaction site selectivity, which can realize arylation at the C4-position. Various sodium arylsulfinates are well tolerated under the mild reaction conditions. The current study makes the arylation of general alkenyl halides possible by the use of cheap and easily available sodium arylsulfinates as aryl sources.

MnO2/graphene nanocomposites with different morphologies were synthesized and the petal-shaped nanosheet MnO2/graphene composite was developed as an electrode material for nonenzymatic hydrogen peroxide (H2O2) sensor. The morphology, structure, composition, and hydrophilicity of the resulting products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and the contact angle tests. In addition, the fabricated MnO2/graphene composites could be used as catalysts for the electrochemical oxidation of H2O2. Cyclic voltammogram (CV) experiments indicated that MnO2/graphene-modified electrode showed good electrocatalytic activity towards both the oxidation and reduction of H2O2 in a neutral environment. Amperometric response results illustrated that this nonenzymatic sensor had excellent anti-interference ability and displayed two linear ranges from 10 to 90 µM and from 0.2 to 0.9 mM with a detection limit of 2 µM.

A new and fast sample preparation technique based on three-phase hollow fiber liquid-phase microextraction with a magnetofluid was developed and successfully used to quantify the aristolochic acid I (AA-I) and AA-II in plasma after oral administration of Caulis akebiae extract. Analysis was accomplished by reversed-phase high-performance liquid chromatography with fluorescence detection. Parameters that affect the hollow fiber liquid-phase microextraction processes, such as the solvent type, pH of donor and acceptor phases, content of magnetofluid, salt content, stirring speed, hollow fiber length, extraction temperature, and extraction time, were investigated and optimized. Under the optimized conditions, the preconcentration factors for AA-I and AA-II were >627. The calibration curve for two AAs was linear in the range of 0.1-10 ng/mL with the correlation coefficients >0.9997. The intraday and interday precision was

Cytokine profiles may impact the pathogenicity and severity of hand, foot, and mouth disease caused by human enterovirus (HEV) 71. In 91 severe or mild HEV 71-associated hand, foot, and mouth disease children, serum was collected between days 2 and 10 or day >10. Serum cytokines including Type 1 T helper (Th1) cytokines: interleukin (IL)-2, interferon-gamma (IFN-γ), IL-12, and IL-18, Type 1 T helper (Th2) cytokines: IL-4, IL-10, IL-13, proinflammatory cytokines: IL-1α, IL-1β, IL-6, IL-8, IL-17, and tumor necrosis factor alpha (TNF-α), were assessed during the early stage and recovery. In the patients with mild illness, the peaks of IL-8 and IL-10 were observed on day 6 and that of IL-18 was on day 4. In the patients with severe illness, all cytokines spiked on day 3 and peaked on day 11. All cytokines except IL-6, IL-8, IL-18, and TNF-α were significantly correlated with immunoglobulin M levels by the end of the disease course. Cytokine profile variations between the patients with mild and severe illness may indicate prognosis and strain virulence, useful in clinical treatment of patients.

Two coordination polymers, [Mn2(btc)(phen)4]n·7nH2O (1) and [Co2(btc)(phen)(H2O)2]n·nH2O (2) (H4btc = biphenyl-3, 3′,4, 4′-tetracarboxylic acid, phen = 1, 10-phenanthroline) were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Compound 1 has a 1D chain structure in which the dinuclear Mn2 units are linked through (btc)4– ligands. Magnetic measurements revealed weak antiferromagnetic and ferromagnetic exchange coupling interactions between MnII and CoII ions in 1 and 2, respectively. Moreover, both compounds have good thermal stabilities.

BACKGROUND Furaltadone (FTD) is a type of nitrofuran and has been banned in many countries as a veterinary drug in food-producing animals owing to its potential carcinogenicity and mutagenicity. FTD is unstable in vivo, rapidly metabolizing to 3-amino-5-methylmorpholino-2-oxazolidinone (AMOZ); thus AMOZ can be used as an indicator for illegal usage of FTD. Usually, for the determination of nitrofurans, the analyte is often a derivative of the metabolite rather than the metabolite itself. In this study, based on the monoclonal antibody (mAb) against AMOZ, a competitive immunochromatographic assay (ICA) using a colloidal gold–mAb probe for rapid and direct detection of AMOZ without a derivatization step in meat and feed samples was developed. RESULTS The intensity of red color in the test line is inversely related to the analyte concentration and the visual detection limit was found to be 10 ng mL−1. The performance of this assay was simple and convenient because the tedious and time-consuming derivatization step was avoided. The ICA detection was completed within 10 min. The ICA strips could be used for 7 weeks at room temperature without significant loss of activity. The AMOZ spiked samples were detected by ICA and confirmed by enzyme-linked immunosorbent assay. The results of the two methods were in good agreement. CONCLUSION The proposed ICA provides a feasible tool for simple, sensitive, rapid, convenient and semi-quantitative detection of AMOZ in meat and feed samples on site. To our knowledge, this is the first report of the ICA for direct detection of AMOZ. © 2013 Society of Chemical Industry

Staphylococcal nuclease domain containing 1 (SND1) is a ubiquitously expressed multifunctional protein involved in transcriptional regulation, RNA splicing and RNA metabolism. Ectopic expression of SND1 has been observed in various tumors including colon cancer, breast cancer, prostate cancer and hepatocellular carcinoma (HCC), indicating a positive role of SND1 in tumor initiation and progression. However, the exact role of SND1 in cancers has not been thoroughly investigated. In the present study, we investigated the role of SND1 in HCC. Immunohistochemistry analysis revealed that the expression level of SND1 was higher in HCC tissues than in adjacent nontumor tissues. Stable knock-down of SND1, performed on the HCC cell line SMMC-7721 using shRNA lentiviral expression system, led to reduced cell proliferation, clone formation and tumor formation in nude mice. The insulin-like growth factor (IGF) signaling pathway was frequently dysregulated in HCC, which could facilitate tumor progression. Screening of gene expression levels of the IGF pathway, using real-time PCR, revealed that a decrease in SND1 expression could increase the expression of IGF-binding protein 3 (IGFBP3), which can negatively regulate activation of the IGF pathway by restricting interactions between IGF and IGF receptors. Results from previous studies showed that the downregulation of IGFBP3 expression is a common feature in HCC, and the upregulation of IGFBP3 expression could suppress HCC cells proliferation. We further confirmed that stable knock-down of IGFBP3 could promote SMMC-7721 cells proliferation. Therefore, we concluded that SND1 could affect SMMC-7721 cells proliferation by regulating IGFBP3 expression and IGF signaling pathway. Anat Rec, 296:1568–1575, 2013. © 2013 Wiley Periodicals, Inc.

The β-diketonate derivative ligand [H2L = 6-(3-hydroxy-1-oxo-3-pyrryl-2-propen-1-yl)-2-pyridinecarboxylic acid] and its zinc(II) coordination complexes, [Zn(H2L)Cl2]·(EtOH)(H2O) (1) and [Zn4(L)4(H2O)2]·5H2O (2), were prepared and characterized by elemental analysis, IR and NMR spectroscopy, and single-crystal X-ray diffraction. Complex 1 is a mononuclear structure. Complex 2 is a [2 × 2] grid tetranuclear structure. The luminescent properties of the free ligand H2L and complexes 1 and 2 in methanol solution were studied.

Fluorenes have been synthesized through an efficient novel Pd-catalyzed tandem cross-coupling reaction; these substrates are fascinating building blocks found in organic photoelectric materials. The position of the substituent on fluorenes could be conveniently tuned by changing the halogen in the ortho-halobenzyl bromide substrates when coupled with various arylboronic acids. This newly developed synthetic approach could achieve the potential diversity in fluorene-based molecular architectures.

It is important to understand the ecophysiological characters of plants when exploring mechanisms underlying species substitution in the process of plant succession. In the present study, we selected 34 woody species from different stages of secondary succession in subtropical forests of southern China, and measured their hydraulic conductivity, gas exchange rates, leaf nutrients and drought-tolerance traits such as xylem resistance to cavitation, turgor loss point and carbon isotope ratio. Principal component analysis revealed that early-, mid- and late-successional species were significantly separated along axis 1, which was strongly associated with hydraulic-photosynthetic coordination. In contrast to species distributed in late-successional forest, early-successional species had the highest hydraulic conductivity, net photosynthetic rates, photosynthetic nitrogen and phosphorus use efficiencies, but had the lowest photosynthetic water-use efficiency. However, changes of the measured drought-tolerance traits of the 34 species along the succession did not demonstrate a clear trend - no significant correlations between these traits and plant successional stages were found. Moreover, the trade-off between hydraulic efficiency and safety was not identified. Taken together, our results suggested that hydraulic efficiency and photosynthetic function, rather than drought tolerance, play an important role in species distributions along plant succession in subtropical forests.

The adult hippocampus is one of the primary neural structures involved in memory formation. In addition to synapse-specific modifications thought to encode information at the sub-cellular level, changes in the intrahippocampal neuro-populational activity and dynamics at the circuit-level may contribute substantively to the functional capacity of this region. Within the hippocampus, the dentate gyrus has the potential to make a preferential contribution to neural circuit modification owing to the continuous addition of new granule cell population. The integration of newborn neurons into pre-existing circuitry is hypothesized to deliver a unique processing capacity, as opposed to merely replacing dying granule cells. Recent studies have begun to assess the impact of hippocampal neurogenesis by examining the extent to which adult-born neurons participate in hippocampal networks, including when newborn neurons become engaged in ongoing network activity and how they modulate circuit dynamics via their unique intrinsic physiological properties. Understanding the contributions of adult neurogenesis to hippocampal function will provide new insight into the fundamental aspects of brain plasticity, which can be used to guide therapeutic interventions to replace neural populations damaged by disease or injury.

Although heat shock protein 70 (Hsp70) has been shown to markedly inhibit H2O2-induced apoptosis in C2C12 cells, and nucleolin/C23 has also been implicated in apoptosis, the relationship of these two molecules is still largely unknown. The aim of the current study was to investigate the potential involvement of nucleolin/C23 in the antiapoptotic mechanism of Hsp70. We found that primary cultures of neonatal rat cardiomyocytes underwent apoptosis upon H2O2 treatment, and in these cells nucleolin/C23 protein was highly unstable and had a half-life of less than 4 h. However, transfection with Hsp70 greatly stabilized nucleolin/C23 and also protected the cells from H2O2-induced apoptosis. When nucleolin/C23 was knocked down with an antisense oligomer, H2O2-induced apoptosis became more severe, even in Hsp70-overexpressed cells, demonstrating an essential role of nucleolin/C23 in the antiapoptotic effects of Hsp70. Similar results were obtained by both nuclear morphology observation and caspase-3 activity assay. Therefore, these data provide evidence that nucleolin/C23 is an essential downstream effecter of Hsp70 in the protection of cardiomyocytes against oxidative stress-induced apoptosis.

A novel coordination polymer [Cd(pc)(phen)(H2O)]n (H2pc = pamoic acid, phen = 1,10-phenanthroline) has been synthesized under hydrothermal conditions. Single crystal X-ray diffraction analysis reveals that the compound crystallizes in triclinic space group P1. All the CdII atoms in the compound are hexacoordinate and are linked by pamoicate ligands to form a one-dimensional zigzag chain. Furthermore, two adjacent zigzag chains are connected by the μ2-(H2O) molecules to form a double-chain with rhombic grids. There exist intermolecular C–H···π contacts, π–π stacking and hydrogen-bonding interactions. Compound 1 displays strong fluorescent emission in the solid state at room temperature.

The hydrothermal reaction of indium chlorine, 2,2’-bipyridine, and 2,3-pyrazinedicarboxylic acid leads to the generation of a mononuclear InIII complex, [In(bpy)(Cl)2]Cl·0.5pz·H2O (1) (bpy = 2,2’-bipyridine, pz = pyrazine). X-ray diffraction analysis indicates that compound 1 crystallizes in the orthorhombic system Pbca space group with a = 12.667(3) A, b = 15.269(3) A, c = 15.859(3) A, V = 3067.4(11) A3 and Z = 8. These discrete units are linked by the hydrogen bondings and C···H–π stacking interactions to form a 3D network. It is interesting to find that the in situ decarboxylation of 2,3-pyrazinedicarboxylic acid into pz ligand was observed.