In situ self-exsolved ultrasmall Fe2P quantum dots from attapulgite nanofibers as superior cocatalysts for solar hydrogen evolution.

Developing highly active, stable, and cost-efficient cocatalysts for photocatalytic H2 evolution is pivotal in the area of renewable energy conversion. Herein, we present a straightforward, low-temperature phosphidation strategy for in situ exsolving doped Fe ions from natural attapulgite (ATP) nanofibers into a supported Fe2P cocatalyst for the photocatalytic H2 evolution reaction (HER). The resulting Fe2P QDs/ATP features highly dispersed Fe2P QDs with an average size of <2 nm and a strong interfacial interaction between self-exsolved Fe2P QDs and the ATP substrate, thus providing ample and stable active sites for the photocatalytic HER. When employed as a cocatalyst, Fe2P QDs/ATP exhibits superior catalytic activity and notable stability in a molecular system with low-cost xanthene dyes as the photosensitizer under visible light irradiation. More importantly, Fe2P QDs/ATP can also efficiently and stably catalyze the photocatalytic HER when simply combined with various semiconductor photocatalysts (g-C3N4, TiO2, and CdS). This strategy of exsolving transition metal ions from substrates is an effective yet simple approach for the development of highly active supported HER cocatalysts for renewable and clean energy conversion.

A study on the viscosity reduction mechanism of high-filled silicone potting adhesive by the formation of Al2O3 clusters.

Heat dissipation has become a key problem for highly integrated and miniaturized electronic components. High thermal conductivity, good flowability and low coefficient of linear thermal expansion (CLTE) are indispensable performance parameters in the field of electronic potting composite materials. In this study, spherical alumina (Al2O3) was surface modified by γ-(2,3-epoxypropoxy) propyltrimethoxy silane (KH560) and γ-aminopropyltriethoxy silane (KH550) and labelled as Al2O3-epoxy and Al2O3-NH2, respectively. Al2O3-epoxy and Al2O3-NH2 powders were equally filled in vinyl silicone oil to prepare a high Al2O3 loading (89 wt%) precursor of silicone potting adhesive. The viscosity of the precursor rapidly decreased with increasing reaction time of Al2O3-epoxy and Al2O3-NH2 at 140 °C. The viscosity reduction mechanism may be due to the formation of some Al2O3 clusters by the reaction of Al2O3-epoxy with Al2O3-NH2, which results in some vinyl silicone oil segments being held in the channel of particles through capillary phenomenon, leading to the friction among Al2O3 clusters decreasing considerably. Laser particle size analysis and scanning electron microscopy (SEM) results confirmed the existence of Al2O3 clusters. Energy dispersive spectroscopy (EDS) and dynamic viscoelasticity experiments revealed that some segments of vinyl silicone oils were held by Al2O3 clusters. When Al2O3-epoxy and Al2O3-NH2 reacted for 4 h, the thermal conductivity, CLTE and volume electrical resistivity of the silicone potting adhesive reached 2.73 W m-1 k-1, 75.8 ppm/°C and 4.6 × 1013 Ω cm, respectively. A new strategy for preparing electronic potting materials with high thermal conductivity, good flowability and low CLTE is presented.

Synthesis, Characterization of NR@SiO2/PNIPAm-co-Ppa Composite Nanogel and Study On Its Application in Photodynamic Therapy.

In the present study, a novel composite nanogel based on fluorescence resonance energy transfer (FRET) and its application for photodynamic therapy is reported. First of all, nanoparticles of silica doped with Nile Red (NR) were prepared by Stöber method, then they were decorated by γ-methacryloxypropyltrimethoxysilane (MPS) to prepare MPS decorated NR@SiO2 nanoparticles, and finally they were copolymerized with N-isopropylacrylamide (NIPAm) and Pyropheophorbide-a (Ppa) by free radical copolymerization, and composite nanogel of NR@SiO2/PNIPAm-co-Ppa was fabricated. The microstructure of the as-prepared nanogel was characterized by Fourier transform infrared spectrum (FTIR), photoluminescence (PL), UV-Visible spectrophotometer (UV-Vis), dynamic light scattering (DLS) and transmission electron microscopy (TEM). PL spectrum indicated that, under irradiation of visible light source, energy can be transferred from NR to Ppa. UV-Vis spectrum demonstrated that aggregation of Ppa is prevented efficiently and Ppa exists as "monomer" state in the composite nanogel. Under irradiation of laser, singlet oxygen (1O2) can be produced efficiently by excited nanogel. The in vitro cytotoxicity test showed that HeLa cells can be killed by the composite nanogel.

Preparation, stimuli-response performance of HPC-PMAA/PpIX nanogels and their application in photodynamic therapy.

In the present study, a novel nanogel of HPC-PMAA/PpIX with thermo- and pH sensitive performance and its application in cancer photodynamic therapy is reported. HPC-PMAA/PpIX nanogels were prepared by free radical polymerization method with HPC as template, hydroxypropyl cellulose (HPC), methyl acrylic acid (MAA), protoporphyrin IX (PpIX) and N,N'-methylene bisacrylamide (BIS) as raw materials. The as-prepared nanogels were characterized by Fourier transform infrared (FTIR), photoluminescence (PL) and UV-visible spectrophotometer (UV-vis), dynamic light scattering (DLS) and transmission electron microscopy (TEM). PL and UV-vis spectra demonstrate that PpIX is incorporated into HPC-PMAA by covalent bonds, and its aggregation is prevented. Moreover, the as-prepared nanogels can be dispersed in water over 1 week, significant singlet oxygen can be produced under irradiation of laser. With tumor cell of HepG2 as model cell, the nanogels are biocompatible with cell viability of >85% even at high concentrations of the PpIX in vitro. In addition, the HPC-PMAA/PpIX nanogels show photo-dependent toxicity in the concentration range of 10 µg/mL of PpIX, suggesting that HPC-PMAA/PpIX nanogels have potential for the treatment of photodynamic therapy (PDT).

[Protective effects of combined use of atorvastatin and low molecular weight heparin on the inflammatory reaction and pulmonary functions in rats with sepsis].

Objective: To investigate the influence of combined use of atorvastatin (ATO) and low molecular weight heparin (LMWH) on the inflammatory reaction and pulmonary protection functions in rats with sepsis. Methods: A total of 122 healthy male Sprague-Dawley (SD) rats were divided into five groups using a random number table: sham-operated group (sham group, n =10),sepsis group (n =10),ATO group (n =34),LMWH group (n =34),and ATO combined with LMWH group (ATO+LMWH group, n =34).The rat model of sepsis was reproduced by cecal ligation and puncture (CLP),while in sham group, rats were only subjected to laparotomy without cecum ligation and puncture. The rats of each pretreatment group received relevant therapies for 5 days, either gastric perfusion with ATO 20 mg/kg or subcutaneous injection with LMWH 100 U/kg or both before operation. The sepsis severities of the model animals were scored according to the modified sepsis severity assessment standards of experimental animals. Ten rats in each group were calculated the 7-day cumulative mortality rate. Blood samples from 6 rats in each group were collected to determine the levels of tumor necrosis factor-α (TNF-α),interleukin-1 ß (IL-1 ß) and high mobility group protein box-1 (HMGB1) contents in plasma using enzyme linked immunosorbent assay (ELISA)before operation (0 hour) and 4,8,12,and 24 hours post operation. The lung tissue was harvested 24 hours after operation, and the pulmonary pathology was assayed by hematoxylin and eosin (HE) staining using optical microscope. Results: ① The sepsis severity grades of sepsis group were significantly higher than those of sham group at 4 hours after operation (score:12.2 ± 2.0 vs.7.2 ± 0.5,P ＜ 0.05).Furthermore, they displayed a gradually increasing tendency, with the 7-day cumulative mortality rate being 90％ (9/10).The sepsis severity grades in ATO group, LMWH group, and ATO+LMWH group showed a significant decrease compared with sepsis group at 8 hours after operation (12.2± 2.0,11.2±2.2,10.0± 1.7 vs.16.6±2.5,all P ＜ 0.05).The 7-day cumulative mortality rates in ATO group, LMWH group, and ATO+LMWH group were 60％ (6/10),60％ (6/10),and 40％ (4/10),respectively, all of which was significantly lower than that of sepsis group (all P ＜ 0.05).② The levels of TNF-α,IL-1 ß and HMGB1 have not shown much variations in the sham group after operation; the levels of pro-inflammatory cytokines in other 4 groups were significantly increased after operation compared with those before operation; the levels of TNF-α,IL-1ß,and HMGB 1 reached peak at 4,8,and 24 hours, respectively. The levels of pro-inflammatory cytokines in sepsis group were significantly higher than those in the sham group. However, the levels of pro-inflammatory cytokines in ATO group, LMWH group, and ATO+LMWH group were significantly lower than those in sepsis group [4-hour TNF-α (ng/L):668.3 ± 124.6,536.5 ± 118.5,496.5 ± 108.5 vs.783.8 ± 134.7;8-hour IL-1 ß (ng/L):2 476.7 ± 137.8,2 460.4± 171.2,2 090.0 ± 151.2 vs.2 873.9 ± 295.6;24-hour HMGB1 (µg/L):654.4± 154.4,659.0± 134.6,609.4±90.5 vs.859.3 ± 167.5,P ＜ 0.05 or P ＜ 0.01].③ It was showed by optical microscopy that the pulmonary tissue morphology was normal in sham group and that the damage of pulmonary pathology was relatively severe in sepsis group. Compared with sepsis group, the damage of pulmonary pathology in ATO group, LMWH group, and ATO + LMWH group was alleviated obviously, and the most obvious improvements were found in ATO + LMWH group. Conclusions: Either ATO or LMWH could decrease sepsis severity, suppress the release of plasma pro-inflammatory cytokines at the early and late stages, alleviate the damage of pulmonary pathology, and reduce the 7-day cumulative mortality rate. Therefore, the combined treatment of sepsis using both ATO and LMWH resulted in better outcomes than implemented individually.

[Inhibitory effects of curcumin on inflammatory cytokines in rats with paraquat poisoning].

OBJECTIVE: To explore the mechanism of paraquat (PQ) poisoning and to observe the changes in inflammatory cytokines in PQ-exposed rats treated in different ways. METHODS: Fifty 8-week-old clean male Wistar rats were randomly divided into high-dose curcumin plus conventional treatment group, low-dose curcumin plus conventional treatment group, high-dose curcumin group, PQ poisoning group, and blank control group. On days 1, 3, 5, 7, 14, and 21 after PQ exposure, serum levels of transforming growth factor-ß1(TGF-ß1) , tumor necrosis factor-α (TNF-α) , and interleukin-6 (IL-6) were measured. The pathological changes in lung tissue were evaluated by HE staining. RESULTS: Compared with the blank control group, the high-dose curcumin plus conventional treatment group, low-dose curcumin plus conventional treatment group, high-dose curcumin group, and PQ poisoning group had significantly increased serum levels of TGF-ß1, TNF-α, and IL-6 (P<0.05) , and the three cytokines in each group reached peak levels on day 14 after exposure. Compared with the PQ poisoning group, the high-dose curcumin group had significantly reduced serum levels of TGF-ß1, TNF-α, and IL-6 (P<0.05). On day 21 after exposure, there were no significant differences in serum levels of TGF-ß1, TNF-α, and IL-6 between the high-dose curcumin plus conventional treatment group and the low-dose curcumin plus conventional treatment group (P>0.05). The HE staining revealed alveolar inflammatory changes on days 1~7 and massive pulmonary fibrosis on days 14~21 in the high-dose curcumin plus conventional treatment group, low-dose curcumin plus conventional treatment group, high-dose curcumin group, and PQ poisoning group, but the above changes were milder in the high-dose curcumin group than in the PQ poisoning group. CONCLUSION: For rats with PQ poisoning, curcumin can significantly reduce inflammatory response and pathological changes in lung tissue and inhibit and delay the development and progression of body injury.

[Case-control study on minimally invasive plate osteosynthesis for the treatment of proximal humeurs fractures in elderly patients].

OBJECTIVE: To compare clinical efficacy for the treatment of proximal humeurs fractures in elderly patients between the minimally invasive plate osteosynthesis (MIPO) with less invasive stabilization system (LISS) and the open reduction and internal fixation (ORIF) with locking compression plate (LCP). METHODS: From June 2008 to June 2011, 40 elderly patients suffering from proximal humeurs fractures were divided into two groups: 20 cases in minimally invasive group and 20 cases in routine group. Mini-incision approach from the lateral shoulder (minimally invasive group) and LISS can be chosen. It was short for MIPO. The antero-medial incision was used in routine group, LCP can be chosen in the method of ORIF. The operation time, the blood loss, the incision length, soreness at 1st, 3rd and 7th days after operation were recorded. The postoperative Neer score, the healing time of bone were recorded. The curative effects were compared according to Neer score system. RESULTS: The mean operation times were (133.60 +/- 8.90) min and (132.70 +/- 8.41) min in minimally invasive group and routine group (P > 0.05). The blood losses were (155.20 +/- 19.07) ml and (324.05 +/- 48.32) ml (P < 0.05). The incision lengths were (8.15 +/- 1.89) cm and (13.05 +/- 1.95) cm (P < 0.05). The pain scores on the 1st,3rd and 7th days after operation were (6.20 +/- 2.39) and (8.33 +/- 3.01) (P < 0.05), (3.83 +/- 2.09) and (5.31 +/- 2.22) (P < 0.05), (1.22 +/- 0.89) and (3.13 +/- 1.75) (P < 0.05). The postoperative Neer scores were 93.16 +/- 2.55 and 80.31+/- 2.22 (P < 0.05) and the healing times of bone were (6.60 +/- 2.33) months and (8.93 +/- 3.41) months (P < 0.05). There were statistially differences in the blood losses, incision lengths, postoperative pain scores, postoperative Neer scores and the healing times of bone between two groups (P < 0.05). The operation time between the two groups had no statistically different (P > 0.05). According to Neer score system, 13 patients obtained an excellent results, 2 good, 5 fair in minimally invasive group; 6 patients obtained an excellent results, 5 good, 9 fair in routine group. CONCLUSION: To compare with the routine group of ORIF, MIPO with LISS has the advantages of small incision, easier operation, less blood loss and improved postoperative shoulder joint function recovery for treatment of proximal humeurs fracture in elderly patients. It is another better method of internal fixation.