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Heterometallic clusters have attracted broad interests in the synthetic chemistry due to their various coordination modes and potential applications in heterogeneous catalysis. Here we report the synthesis, experimental, and theoretical characterizations of four ternary clusters ([M2(CO)6Sn2Sb5]3- (M = Cr, Mo), and [(MSn2Sb5)2]4-, (M = Cu, Ag)) in the process of capturing the hypho- [Sn2Sb5]3- in ethylenediamine (en) solution. We show that the coordination of the binary anion to transition-metal ions or fragments provides additional stabilization due to the formation of locally σ-aromatic units, producing a spherical aromatic shielding region in the cages. While in the case of [Mo2(CO)6Sn2Sb5]3- stabilization arises from locally σ-aromatic three-centre and five-centre two-electron bonds, aromatic islands in [(AgSn2Sb5)2]4- and [(CuSn2Sb5)2]4- render them globally antiaromatic. This work describes the coordination chemistry of the versatile building block [Sn2Sb5]3-, thus providing conceptual advances in the field of metal-metal bonding in clusters.

Background: Shock index (heart rate/systolic blood pressure, SI) is a simple scale with prognostic value in patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). The present study introduces an updated version of SI that includes renal function.Methods: A total of 1,851 consecutive patients with STEMI undergoing PCI were retrospectively included at Cardiac Care Unit in Guangdong Provincial People's Hospital and divided into two groups according to their admission time: derivation database (from January 2010 to December 2013, n = 1,145) and validation database (from January 2014 to April 2016, n = 706). Shock Index-C (SIC) was calculated as (SI × 100)–estimated CCr. Calibration was evaluated using the Hosmer-Lemeshow statistic. The predictive power of SIC was evaluated using receiver operating characteristic (ROC) curve analysis.Results: The predictive value and calibration of SIC for in-hospital death was excellent in derivation [area under the curve (AUC) = 0.877, p < 0.001; Hosmer-Lemeshow chi-square = 3.95, p = 0.861] and validation cohort (AUC = 0.868, p < 0.001; Hosmer-Lemeshow chi-square = 5.01, p = 0.756). SIC exhibited better predictive power for in-hospital events than SI (AUC: 0.874 vs. 0.759 for death; 0.837 vs. 0.651 for major adverse clinical events [MACEs]; 0.707 vs. 0.577 for contrast-induced acute kidney injury [CI-AKI]; and 0.732 vs. 0.590 for bleeding, all p < 0.001). Cumulative 1-year mortality was significantly higher in the upper SIC tertile (log-rank = 131.89, p < 0.001).Conclusion: SIC was an effective predictor of poor prognosis and may have potential as a novel and simple risk stratification tool for patients with STEMI undergoing PCI.

Background: The excess volume of contrast media (CM) is a marker of a more severe coronary culprit lesion and longer intervention duration in patients undergoing cardiac procedures. However, it is unclear whether the contrast volume is directly correlated with worse clinical outcomes. The aim of this study was to investigate the association between contrast dose and the incidence of 1-year major adverse cardiac and cerebrovascular events (MACCE) and all-cause bleeding events in patients undergoing cardiac catheterization and coronary angiography (CAG). Methods: We prospectively enrolled 10,961 consecutive patients diagnosed with coronary heart disease expecting CAG from 2012 to 2013. The study population was pursued with a follow-up duration of 1 year. The predictive value of contrast volume, divided into quartiles, for the risk of MACCE and all-cause bleeding events was assessed using logistic regression analysis. Results: The cumulative incidence of 1-year MACCE was 8.65%, which was directly associated with increasing contrast volume. In particular, MACCE was observed in 7.16%, 7.89%, 9.31%, and 11.73% of cases in the contrast volume quartile Q1 (≤100 ml), Q2 (101–140 ml), Q3 (141–200 ml), and Q4 (>200 ml), respectively (P < 0.001). Moreover, the incidence of 1-year all-cause bleeding events was noted in 4.70%, 5.93%, 7.28%, and 8.21% of patients in Q1, Q2, Q3, and Q4, respectively (P < 0.001). The survival analysis showed that the 1-year MACCE rate was higher in patients using greater CM volume during the CAG. CM volume used >140 ml was associated with the occurrence of 1-year MACCE, and the incidence was dramatically elevated in patients exceeding a contrast volume of 200 ml (P = 0.007). Conclusion: Our data suggested that higher contrast volume was significantly correlated with an increased risk of MACCE and all-cause bleeding events in patients undergoing cardiac catheterization. Trial Registration: ClinicalTrials.gov, NCT01735305; https://clinicaltrials.gov/ct2/show/NCT01735305?id=NCT017353057rank=1.

Comprehensive Summary: Binary polyantimony clusters, namely [Cu2Sb14]4– and [Ag2Sb14]4–, containing coinage metals, were successfully synthesized and characterized, in which two homoatomic Sb73– subunits are bridged by two coinage metals in η4:η1 and η1:η1 coordination modes, respectively. In [Cu2Sb14]4–, two bridging Cu ions and two Sb atoms form a planar rhombic unit, which was revealed to have antiaromatic properties by theoretical calculations. Further electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M+ ions. [ABSTRACT FROM AUTHOR]

The C 60 fullerene molecule has attracted tremendous interest for its distinctive nearly spherical structure. By contrast, all-metal counterparts have been elusive: Fullerene-like clusters composed of noncarbon elements typically suffer from instability, resulting in more compact geometries that require multiple embedded atoms or external ligands for stabilization. In this work, we present the synthesis of an all-metal fullerene cluster, [K@Au 12 Sb 20 ] 5- , using a wet-chemistry method. The cluster's structure was determined by single crystal x-ray diffraction, which revealed a fullerene framework consisting of 20 antimony atoms. Theoretical calculations further indicate that this distinct cluster exhibits aromatic behavior.

Objective: To explore the multi-differentiated capability of human dental pulp stem cells (hDPSCs) obtained by cell-clone culture approach and to determine the appropriate induced medium., Methods: The cloned isolation and expansion of hDPSCs were preinduced for 24 h, and were subsequently replaced with neural-inductive medium containing certain concentration of dimethylsulfoxide (DMSO), butylated hydroxyanisode (BHA), forskolin, P-mercaptoethanol (p-ME) and hydrocortisone for 4 days. Then induced cells were analyzed by morphological observation, immnocytochemical staining for non-specific esterase (NSE) and glial fibrillary acidic protein (GFAP) expression, RT-PCR for GFAP mRNA. Meanwhile, the uninduced hDPSCs were used as negative control., Results: The morphology of induced cells changed at the initial 12 h, and displayed a typical neuron-like cells at 24 h. There was a gradual increase in the number of these neuronal differentiated cells with continuous induction. Furthermore, immnocytochemical staining showed that the induced cell expressed NSE and GFAP, two marked enzymes of neuron cell. The GFAP mRNA was also detected in induced cells by RT-PCR assay. In contrast, the uninduced cells maintained its original appearance and had no expression on them., Conclusion: hDPSCs may possess potential of multiple-differentiation and may differentiate into neuron-like cells on certain inductive condition.