Salen-Based Conjugated Microporous Polymers for Efficient Oxygen Evolution Reaction.

Exploring high-performance electrocatalysts, especially non-noble metal electrocatalysts, for the oxygen evolution reaction (OER) is critical to energy storage and conversion. Herein, we report for the first time that conjugated microporous polymers (CMPs) incorporating salen can be used as OER electrocatalysts with outstanding performances. The best OER electrocatalyst (salen-CMP-Fe-3) exhibits a low Tafel slope of 63 mV dec-1 and an overpotential of 238 mV at 10 mA cm-2 . DFT and Grand Canonical Monte Carlo calculations confirmed that the significantly improved electrocatalytic properties can be attributed to the intrinsic catalytic activity of the salen moiety and the enrichment effect of the pore structures. This work demonstrates that salen-based conjugated polymers are a type of metal-coordinated porous polymer that show excellent catalyst performance.

Exceptional Antisintering Gold Nanocatalyst for Diesel Exhaust Oxidation.

The poor thermodynamic stability of gold nanoparticles (NPs) makes it very challenging to stabilize them in small sizes at elevated temperatures. Herein, we report the preparation of antisintering Au nanocatalyst by rationally selecting the sublattice matched MgGa2O4 spinel as support based on theoretical predictions. Au/MgGa2O4 retains Au NPs of 2-5 nm even after aging over the melting temperature of bulk gold (1064 °C)! By identifying the stable structure, the extraordinary stability is found to arise from the formation of a new phase structure, namely Au-MgGa2O4 metal-oxide "hetero-bicrystal" that remains as crystallite without melting even at 1100 °C. More than 80% of the loaded Au can be efficiently stabilized so that the catalysts can exhibit excellent low-temperature activities for diesel exhaust (CO and C3H6) oxidation after severely thermal and hydrothermal aging. These results may pave ways for constructing antisintering gold nanocatalysts for industrial applications.

[Tongjingling reduces ROS level and improves mitochondrial function in spermatogenic cells of varicocele rats with liver-qi stagnation].

OBJECTIVE: To explore the effects of the Chinese herbal compound Tongjingling (TJL) on the ROS level, mitochondrial membrane potential (MMP) and mitochondrial ultrastructure in spermatogenic cells in varicocele (VC) rats with liver-qi stagnation (LQS). METHODS: Totally, 72 male SPF Wistar rats were randomly divided into six groups of equal number, sham operation, VC+LQS model, low-, medium- and high-dose TJL, and L-carnitine (LC) control. The VC+LQS model was established by the Saypol method combined with tail-clamping. At 4 weeks after modeling, the rats in the low-, medium- and high-dose TJL groups were treated intragastrically with TJL at 0.6, 1.2 and 2.4 g/ml respectively, those in the sham operation and VC+LQS model groups with 0.9% saline, and those in the LC control group with LC oral liquid at 2.1 ml/kg, qd, for 8 weeks. Then the ROS level and MMP in the spermatogenic cells were measured by flow cytometry and the mitochondrial ultrastructure observed under the transmission electron microscope. RESULTS: The ROS level in the spermatogenic cells was significantly higher in the VC+LQS model and low-dose TJL groups than in the sham operation group (ï¼»62.72 ± 9.90ï¼½% and ï¼»52.25 ± 8.15ï¼½% vs ï¼»36.53 ± 5.25ï¼½%, P < 0.01), but remarkably lower in the medium-dose TJL (ï¼»41.65 ± 4.89ï¼½%), high-dose TJL (ï¼»39.60 ± 5.19ï¼½%) and LC control (ï¼»38.33 ± 7.46ï¼½%) than in the VC+LQS model group (P < 0.01). MMP in the spermatogenic cells was significantly lower in the VC+LQS model and low-dose TJL than in the sham operation group (ï¼»34.80 ± 20.18ï¼½% and ï¼»44.39 ± 19.60ï¼½% vs ï¼»60.24 ± 22.25ï¼½%, P < 0.01 and P < 0.05), but markedly higher in the medium-dose TJL (ï¼»50.62 ± 14.83ï¼½%), high-dose TJL (ï¼»52.42 ± 7.55ï¼½%) and LC control (ï¼»50.75 ± 15.65ï¼½%) than in the VC+LQS model group (P < 0.05). The mitochondria in the spermatogenic cells of the VC+LQS model rats exhibited swelling, vacuolization, rupture or disappearance of the mitochondrial cristae, and breakdown of the internal structure. The pathological injury of the mitochondrial structure was improved in different degrees in the TJL and LC groups. CONCLUSIONS: TJL can reduce the ROS level, increase MMP and improve pathological injury of the mitochondrial ultrastructure in the spermatogenic cells of VC rats with LQS, which may be the underlying molecular mechanism of TJL improving fertility in infertile VC patients.

Enhanced carbon dioxide conversion at ambient conditions via a pore enrichment effect.

Chemical fixation of carbon dioxide (CO2) may be a pathway to retard the current trend of rapid global warming. However, the current economic cost of chemical fixation remains high because the chemical fixation of CO2 usually requires high temperature or high pressure. The rational design of an efficient catalyst that works at ambient conditions might substantially reduce the economic cost of fixation. Here, we report the rational design of covalent organic frameworks (COFs) as efficient CO2 fixation catalysts under ambient conditions based on the finding of "pore enrichment", which is concluded by a detailed investigation of the 10994 COFs. The best predicted COF, Zn-Salen-COF-SDU113, is synthesized, and its efficient catalytic performance for CO2 cycloaddition to terminal epoxide is confirmed with a yield of 98.2% and turnover number (TON) of 3068.9 under ambient conditions, which is comparable to the reported leading catalysts. Moreover, this COF achieves the cycloaddition of CO2 to 2,3-epoxybutane under ambient conditions among all porous materials. This work provides a strategy for designing porous catalysts in the economic fixation of carbon dioxide.

Dihydrotestosterone modulates endothelial progenitor cell function via RhoA/ROCK pathway.

BACKGROUND: Previous findings indicate that testosterone level is negatively correlated with the incidence and mortality of cardiovascular diseases in men. Endothelial progenitor cells (EPCs) play a critical role in endothelial healing and vascular integrity. This study aimed to examine the effects of dihydrotestosterone (DHT), an active metabolite of testosterone, on human EPC function and investigate the underlying mechanism. METHODS: EPCs were isolated from peripheral blood of healthy adult males and incubated with a series of concentrations (1, 10, and 100 nmol/L in dimethyl sulfoxide) of DHT for 24 h or with 10 nmol/L DHT for different periods (6, 12, 24, 36, and 48 h). EPC proliferation, migration, and adhesion were determined by MTT assay, modified Boyden chamber assay, and cell counting, respectively. Furthermore, vascular endothelial growth factor (VEGF) production was examined by ELISA, RhoA activity was determined through pull-down assay. The protein level of RhoA was quantified by Western blot analysis. RESULTS: DHT significantly increased the proliferative, migratory, and adhesive abilities of EPCs in a dose- and time-dependent manner and upregulated the levels of VEGF and activated RhoA. However, RhoA inhibitor C3 exoenzyme or ROCK inhibitor Y-27632 significantly inhibited DHT-induced proliferation, migration, and adhesion, as well as VEGF production. Moreover, C3 exoenzyme inhibited the activation of RhoA stimulated by DHT. CONCLUSIONS: DHT promotes EPC proliferation, migration, and adhesion activities via RhoA/ROCK pathway.

Low-molecular-weight heparin and intermittent pneumatic compression for thromboprophylaxis in critical patients.

The efficacy and safety of physiotherapeutic prophylaxis for venous thromboembolism in critically ill patients with heparin contraindication remains unclear. In the present study it was hypothesized that physiotherapy prophylaxis with intermittent pneumatic compression (IPC) would be safe and effective for patients unable to receive low-molecular-weight heparin (LMWH). In addition, this study investigated whether a combined therapy of IPC with LMWH would be more effective for the prophylaxis of deep vein thrombosis (DVT) in critical patients. A total of 500 patients were divided into four groups according to the prophylaxis of DVT. The IPC group consisted of 95 patients with heparin contraindication that received IPC treatment; the LMWH group consisted of 185 patients that received an LMWH injection; the LMWH + IPC group consisted of 75 patients that received IPC treatment and LMWH injection; and the control group consisted of 145 patients that received no IPC treatment or injection of LMWH. Each patient was evaluated clinically for development of DVT and the diagnosis was confirmed by Doppler study. Venous thromboembolism was a common complication among the trauma patients with severe injuries. Patients responded positively to the treatment used in the intervention groups. Patients exhibited an improved response to LMWH + ICP compared with IPC or LMWH alone, while no significant difference was detected between the IPC and LMWH groups. These results were applicable to patients that had a Wells score of ≥3; however, no significant differences in DVT incidence were observed among the patients who had a Wells score of <3. In this observational study, LMWH + ICP appeared to be more effective than either treatment alone in treating critically ill trauma patients with severe injuries that are at high risk for VTE and bleeding simultaneously.

[Clinical research of genetic counseling].

To supply reliable materials for the assessment of recurrence risk,prenatal diagnosis and the supervision of high risk persons,we analyzed 10811 patients with the methods of cytogenetics,fluorescent in situ hybridization and molecular genetic PCR methods. The result of cytogenetics:there were 555 abnormal karyotypes of peripheral blood on 5390 cases (10.30%);In 2171 patients who asked for prenatal diagnosis,145 abnormal karyotypes were found (6.68%);We also karyotyped chorionic villous cells of 62 patients with spontaneous abortion and found 28 abnormal karyotypes (45.16%). The PCR results of 23 patients with Down's syndrome were all positive while the results of 155 normal persons were all negative. The method of cytogenetics is very important for diagnosis of abnormal karyotypes;Molecular genetic methods by PCR and FISH are quick,convenient and applicable way.