Two-Coordinate Dinuclear Donor-Gold(I)-Acceptor Complexes Exhibiting Multiple Excitation Wavelength Dependent Phosphorescence.

Two-coordinate Au(I) complexes with a donor-metal-acceptor (D-M-A) structure have shown rich luminescent properties. However, charge-neutral dinuclear donor-metal-acceptor type Au(I) complexes featuring aurophilic interactions have been seldom explored. Herein, we describe the structures and photoluminescence properties of two dinuclear Au(I) complexes, namely DiAu-Ph and DiAu-Me. Single crystal X-ray structural analysis of DiAu-Ph reveals a short intramolecular Au-Au distance of 3.224 Å. In dilute solution and doped films, excitation wavelength dependent multiple phosphorescence phenomena were observed for these dinuclear complexes. Theoretical calculations reveal that the aurophilic interaction causes increased contribution of the Au d orbital to the highest occupied molecular orbitals. Thus, the gap between singlet and triplet excited states (ΔEST) is enlarged, which disables the thermally activated delayed fluorescence (TADF). Moreover, the large energy separation (0.45-0.52 eV) and the different orbital configurations between the various excited states result in an inefficient internal conversion, accounting for their multiple phosphorescence properties.

In-situ synthesis Fe3C@C/rGO as matrix for high performance lithium-sulfur batteries at room and low temperatures.

People have been focusing on how to improve the specific capacity and cycling stability of lithium-sulfur batteries at room temperature, however, on some special occasions such as cold cities and aerospace fields, the operating temperature is low, which dramatically hinders the performance of batteries. Here, we report an iron carbide (Fe3C)/rGO composite as electrode host, the Fe3C nanoparticles in the composite have strong adsorption and high catalytic ability for polysulfide. The rGO makes the distribution of Fe3C nanoparticles more disperse, and this specific structure makes the deposition of Li2S more uniform. Therefore, it realizes the rapid transformation and high performance of lithium-sulfur batteries at both room and low temperatures. At room temperature, after 100 cycles at 1C current density, the reversible specific capacity of the battery can be stabilized at 889 ± 7.1 mAh/g. Even at -40 °C, in the first cycle battery still emits 542.9 ± 3.7 mAh/g specific capacity. This broadens the operating temperature for lithium-sulfur batteries and also provides a new idea for the selection of host materials for sulfur in low-temperature lithium-sulfur batteries.

Thermally Activated Delayed Fluorescent Binuclear Copper(I) Alkynyl Complexes with Cuprophilic Interactions.

Copper(I)-based thermally activated delayed fluorescence (TADF) emitters have been conceived to be promising candidates for display and lighting applications because of their multifarious structures and strong photoluminescence. Herein a string of binuclear Cu(I) complexes bearing pronounced cuprophilic interactions have been designed and synthesized. [Cu2(dppb)2(µ2-η1-C≡C-Ph)2] (1 a) and [Cu2(dppb)2(µ2-η1-C≡C-PPXZ)2] (1 b) display photoluminescence quantum yields of up to 67 % in doped films and solid states via TADF and exhibit reversible bicolor luminescence switching upon mechanical stimuli. Computational studies manifest that the metal-to-ligand charge transfer predominant transitions ensure a small energy splitting (ΔEST) between the lowest singlet (S1) and triplet (T1) excited states and cuprophilic interactions promote the spin-orbit coupling (SOC), favoring the reverse intersystem crossing (RISC) process. This study provides a new strategy for the construction of stimuli-responsive metal-based TADF materials.

Synthesis of Low-Cost and High-Performance Dual-Atom Doped Carbon-Based Materials with a Simple Green Route as Anodes for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs) are promising alternatives to replace lithium-ion batteries as future energy storage batteries because of their abundant sodium resources, low cost, and high charging efficiency. In order to match the high energy capacity and density, designing an atomically doped carbonous material as the anode is presently one of the important strategies to commercialize SIBs. In this work, we report the preparation of high-performance dual-atom-doped carbon (C) materials using low-cost corn starch and thiourea (CH4N2S) as the precursors. The electronegativity and radii of the doped atoms and C are different, which can vary the embedding properties of sodium ions (Na+) into/on C. As sulfur (S) can effectively expand the layer spacing, it provides more channels for embedding and de-embedding Na+. The synergistic effect of N and S co-doping can remarkably boost the performance of SIBs. The capacity is preserved at 400 mAh g -1 after 200 cycles at 500 mA g-1; more notably, the initial Coulombic efficiency is 81%. Even at a high rate of high current of 10 A g-1, the cell capacity can still reach 170 mAh g-1. More importantly, after 3000 cycles at 1 A g-1, the capacity decay is less than 0.003% per cycle, which demonstrates its excellent electrochemical performance. These results indicate that high-performance carbon materials can be prepared using low-cost corn starch and thiourea.

Distinctive expression signatures of serum microRNAs in ischaemic stroke and transient ischaemic attack patients.

Circulating microRNAs (miRNAs) have recently emerged as promising biomarkers for ischaemic stroke (IS). However, the expression patterns of specific miRNAs in transient ischaemic attack (TIA) patients have not been investigated. Their predictive values for the presence of IS and TIA and their relationships to the neurological deficit severity of IS and the subsequent stroke risk after TIA remain unclear exactly. In this study, 754 miRNAs were initially screened by the TaqMan Low Density Array (TLDA) in two pooled serum samples from 50 IS patients and 50 controls. Markedly altered miRNAs were subsequently validated by individual quantitative reverse-transcription PCR (qRT-PCR) assays first in the same cohort of TLDA and further confirmed in another larger cohort including 177 IS, 81 TIA patients and 42 controls. Consequently, TLDA screening showed that 71 miRNAs were up-regulated and 49 miRNAs were down-regulated in IS patients. QRT-PCR validation confirmed that serum levels of miR-23b-3p, miR-29b-3p, miR-181a-5p and miR-21-5p were significantly increased in IS patients. Strikingly, serum levels of miR-23b-3p, miR-29b-3p and miR-181a-5p were also significantly elevated in TIA patients. Furthermore, up-regulated miR-23b-3p, miR-29b-3p and miR-21-5p could clearly differentiate between IS and TIA patients. Logistic regression and receiver-operating characteristic curve analyses demonstrated that these altered miRNAs may function as predictive and discriminative biomarkers for IS and TIA, and their distinctive expression signatures may contribute to assessing neurological deficit severity of IS and subsequent stroke risk after TIA.

Elevated levels of preß1-high-density lipoprotein are associated with cholesterol ester transfer protein, the presence and severity of coronary artery disease.

BACKGROUND: Preß1-high-density lipoprotein (preß1-HDL), plays an important role in reverse cholesterol transport and exhibits potent risk for coronary artery disease (CAD). However, the association of plasma preß1-HDL and cholesterol ester transfer protein (CETP) levels in CAD patients and the relationship of preß1-HDL with extent of CAD are debatable. METHODS: Preß1-HDL and CETP levels were measured by enzymed-linked immunosorbent assay (ELISAs) in 88 acute coronary syndromes (ACS), 79 stable coronary artery disease (SCAD) patients and 85 control subjects. The correlation analyses, multiple linear regression analyses and logistic regression analyses were performed, respectively. RESULTS: The preß1-HDL and CETP levels in ACS patients were significantly higher than those in SCAD patients and both of them were higher than controls'. Preß1-HDL levels were positively associated with CETP (R = 0.348, P = 0.000), the diameter of stenosis (R = 0.253, P = 0.005), the number of vessel disease (R = 0.274, P = 0.002) and Gensini score (R = 0.227, P = 0.009) in CAD patients. Stepwise multiple linear regression analyses showed that CETP was one of the determinants of preß1-HDL levels. Logistic regression analysis revealed that elevated preß1-HDL and CETP were potential risk factors for both ACS and SCAD. CONCLUSION: The elevated preß1-HDL levels may change with CETP concentrations in CAD patients and were related to the presence and severity of CAD.

Elevated Serum miR-7, miR-9, miR-122, and miR-141 Are Noninvasive Biomarkers of Acute Pancreatitis.

BACKGROUND: It has been reported that several microRNAs (miRNAs), such as miR-141, miR-9, and miR-122, are involved in the regulation of pancreatitis-related proteins or that their levels change in acute pancreatitis (AP) animal models. However, the serum levels, as well as the clinical diagnostic and prognostic values, of these miRNAs in AP patients remain unclear. Furthermore, as a pancreas- (islet) enriched miRNA, miR-7 was reported to be downregulated in AP patients, which requires further verification. METHODS: The levels of miR-7, miR-9, miR-122, and miR-141 were examined and compared using qRT-PCR among 80 severe AP patients, 80 mild AP patients, and 74 healthy controls. RESULTS: The serum levels of these four miRNAs were increased markedly in the AP patients compared with the controls, and these levels decreased significantly after effective therapy. Particularly, the level of miR-7 was higher in severe AP patients than in mild AP patients. ROC curve analysis demonstrated that four miRNAs could be used as potential biomarkers for AP. Moreover, these miRNAs showed strong positive correlations with CRP, which may be associated with inflammation. CONCLUSIONS: The serum miR-7, miR-9, miR-122, and miR-141 levels were increased in AP patients. These 4 miRNAs may represent diagnostic and prognostic biomarkers for AP.

Anti-Sp17 monoclonal antibody-doxorubicin conjugates as molecularly targeted chemotherapy for ovarian carcinoma.

Sperm protein 17 (Sp17) is selectively overexpressed in several human malignancies including ovarian carcinoma, but is absent or expressed at low levels in most normal tissues. Previous work from our group characterized an anti-Sp17 monoclonal antibody (clone 3C12) and showed that it specifically targeted tumor cells. In this report, we investigated whether a novel immunoconjugate containing 3C12 linked to the chemotherapeutic agent doxorubicin [(DOX) Adriamycin] had antitumor activity against ovarian cancer cell lines and tumor models. DOX was conjugated to 3C12 using a linker, and the specificity of 3C12-DOX was examined in Sp17-positive SKOV3 and Sp17-negative COC2 ovarian cancer cells using cell-based ELISA and internalization assays. The cytotoxicity of 3C12-DOX was assessed with the MTT assay, and its therapeutic effectiveness was evaluated in immunodeficient mice bearing SKOV3 cells. In vitro, the 3C12-DOX immunoconjugate specifically bound to and was internalized by Sp17-positive SKOV3 cells but did not bind to Sp17-negative cells. Treatment with 3C12-DOX (0.001 to 10 µg/mL) decreased the viability of SKOV3 cells in a Sp17-specific manner. In vivo, 3C12-DOX (3 mg/kg) induced the regression of established SKOV3 xenograft tumors in BALB/c mice compared with control treatment. The antitumor effects of 3C12-DOX were significantly associated with the induction of apoptosis in tumor cells. In addition, 3C12-DOX showed no observable adverse effects or toxicity when compared with DOX alone in mice bearing ovarian tumor xenografts. Our findings suggest that 3C12-DOX may be a potential antibody-drug conjugate for clinical development.

Anti-Sp17 monoclonal antibody with antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity activities against human ovarian cancer cells.

Sperm protein 17 (Sp17) is a cancer testis antigen that has been shown to be overexpressed in a variety of gynecologic malignancies, in particular ovarian cancer. Emerging evidences indicate that Sp17 is involved in tumorigenesis and in the migration of malignant cells. It has been proposed as a useful target for tumor-vaccine strategies and a novel marker to define tumor subsets and predict drug response. However, the antitumor activity of anti-Sp17 monoclonal antibody (anti-Sp17 mAb) has not been investigated. In this study, the in vitro cytotoxicity, antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) activities of anti-Sp17 mAb were evaluated using Sp17-positive ovarian cancer cells as targets, Sp17-negative ovarian cancer cells as the control, and healthy human peripheral blood monocytes and healthy human serum as effectors. Our preliminary results indicate that the direct cytotoxicity of anti-Sp17 mAb against the investigated ovarian cancer cells was very weak. However, the cytotoxicity of anti-Sp17 mAb, mediated by peripheral blood mononuclear cells (PBMCs), as ADCC, or by human serum, as CDC, was relatively strong in the Sp17-positive ovarian cancer cells. This finding suggested that anti-Sp17 mAb could be a useful tool against ovarian cancer and may provide insight into the development of low side-effect targeting therapy for this malignant disease.

[Inhibition of MYH9 expression by short hairpin RNA expression vector in human umbilical vein endothelial cells (HUVEC)].

AIM: To construct the expression vector of small hairpin RNA (shRNA) and to investigate its efficacy in silencing nonmuscle myosin heavy chain IIA (MYH9)gene. METHODS: According to the MYH9 cDNA sequence in GenBank, three shRNA expression vectors targeting MYH9 gene were constructed and were confirmed by digestion with restriction enzymes and DNA sequencing. The recombinant plasmids were transfected into HUVEC cells. The expression of MYH9 was determined by semi-quantitative RT-PCR at mRNA level and by western blotting at protein level at 24 h, 48 h and 72 h after transfection. RESULTS: The decrease of MYH9 expression at mRNA and protein levels gradually became more evident from 24 h to 48 h, and achieved the maximal degree at 48 h, then became weakened and restored at 72 h. The efficiency of pGCsi-MYH9-3 was the best among these three plasmids. The introduction of pGCsi-MYH9-3 was showed to efficiently and specifically inhibit the expression of MYH9 with inhibitory rate at 71.2% according to results of Western blot. RT-PCR results showed that mRNA transcription of MYH9 gene was reduced by 86.5% at 48 h after introduction of pGCsi-MYH9-3. CONCLUSION: Plasmid pGCsi-MYH9-3 could inhibit MYH9 expression in HUVEC cells successfully and effectively, which promised its further application in related function analysis of MYH9.

Possible mechanism of the anti-inflammatory activity of ruscogenin: role of intercellular adhesion molecule-1 and nuclear factor-kappaB.

Ruscogenin (RUS), first isolated from Ruscus aculeatus, also a major steroidal sapogenin of traditional Chinese herb Radix Ophiopogon japonicus, has been found to exert significant anti-inflammatory and anti-thrombotic activities. Our previous studies suggested that ruscogenin remarkably inhibited adhesion of leukocytes to a human umbilical vein endothelial cell line (ECV304) injured by tumor necrosis factor-alpha (TNF-alpha) in a concentration-dependent manner. Yet the underlying mechanisms remain unclear. In this study, the in vivo effects of ruscogenin on leukocyte migration and celiac prostaglandin E(2) (PGE(2)) level induced by zymosan A were studied in mice. Furthermore, the effects of ruscogenin on TNF-alpha-induced intercellular adhesion molecule-1 (ICAM-1) expression and nuclear factor-kappaB (NF-kappaB) activation were also investigated under consideration of their key roles in leukocyte recruitment. The results showed that ruscogenin significantly suppressed zymosan A-evoked peritoneal total leukocyte migration in mice in a dose-dependent manner, while it had no obvious effect on PGE(2) content in peritoneal exudant. Ruscogenin also inhibited TNF-alpha-induced over expression of ICAM-1 both at the mRNA and protein levels and suppressed NF-kappaB activation considerably by decreasing NF-kappaB p65 translocation and DNA binding activity. These findings provide some new insights that may explain the possible molecular mechanism of ruscogenin and Radix Ophiopogon japonicus for the inhibition of endothelial responses to cytokines during inflammatory and vascular disorders.