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Ag-TiO2 photocatalysts with different doping concentration were prepared by sol-gel method using tetrabutyl titanate and silver nitrate as raw materials. The crystal structure, surface morphology, chemical composition, optical properties of the samples were characterized by XRD, SEM, XPS, DRS and PL, respectively. The photocatalytic activity of xAg-TiO2(x=1%,2%,4%,6%,atom fraction) under UV light and simulated sunlight was evaluated by the degradation of Rhodamine B by using mercury lamp and xenon lamp as the light source, respectively. The results indicate that the photocatalytic activity of TiO2 under UV light and simulated sunlight enhances as the recombination rate of photogenerated electron-hole decreases and the absorption of simulated sunlight increases by Ag doping. 1%Ag-TiO2 exhibits the best photocatalytic activity. The degradation rates of Rhodamine B are 91% under UV light and 89% under simulated sunlight, which are 1.18 and 1.24 times higher than that of pure TiO2. The reaction rate constants are 0.01257 min-1 and 0.01150 min-1, which are 1.49 and 1.74 times higher than that of pure TiO2.

Organic molecules with second near‐infrared (NIR‐II, 1000–1700 nm) emission have significant advantages over NIR‐I (600–900 nm) dyes, and have been widely used as phototheranostic agents (PTAs) and fluorescent probes. However, the two biggest challenges for such reagents are improving photothermal conversion efficiency (PCE), and simplifying tedious synthetic procedures. Herein, different from the traditional NIR skeleton, for the first time, it develops two novel dibenzofulvene‐based NIR‐II emission PTAs via D‐π‐A concept with high PCEs through two simple synthetic steps. The increased intramolecular charge transfer effect and extended π‐conjugation effectively red‐shift their emissions to the NIR‐II region. In addition, the introduction of molecular rotors/vibrators and the formation of π–π stacking prompt the two PTAs to exhibit high PCEs. Notably, FE‐IDMN nanoparticles (FE‐IDMN NPs) achieve an exciting PCE of 82.6%, higher than most reported photothermal agents with NIR‐II emission. FE‐IDMN NPs also possess good colloidal, pH, and photothermal stabilities, as well as excellent photoacoustic response, which is further successfully applied for NIR‐II fluorescence/photoacoustic/photothermal imaging‐guided photothermal therapy. This work provides a simple strategy for constructing new D‐π‐A PTAs with low molecular weight, NIR‐II emission, and high PCE for cancer therapy. [ABSTRACT FROM AUTHOR]

Ag-TiO2 photocatalysts with different doping concentration were prepared by sol-gel method using tetrabutyl titanate and silver nitrate as raw materials. The crystal structure, surface morphology, chemical composition, optical properties of the samples were characterized by XRD, SEM, XPS, DRS and PL, respectively. The photocatalytic activity of xAg-TiO2(x=1%,2%,4%,6%,atom fraction) under UV light and simulated sunlight was evaluated by the degradation of Rhodamine B by using mercury lamp and xenon lamp as the light source, respectively. The results indicate that the photocatalytic activity of TiO2 under UV light and simulated sunlight enhances as the recombination rate of photogenerated electron-hole decreases and the absorption of simulated sunlight increases by Ag doping. 1%Ag-TiO2 exhibits the best photocatalytic activity. The degradation rates of Rhodamine B are 91% under UV light and 89% under simulated sunlight, which are 1.18 and 1.24 times higher than that of pure TiO2. The reaction rate constants are 0.01257 min-1 and 0.01150 min-1, which are 1.49 and 1.74 times higher than that of pure TiO2.

Objective: To initially evaluate the application of artificial vertebra of n-HA/PA66 in anterior reconstruction of lower cervical spine fracture and dislocation., Methods: In this study, 84 patients with lower cervical spine fracture and dislocation received anterior cervical discectomy, spinal canal decompression or subtotal corpectomy, spinal canal decompression and reconstruction by n-HA/PA66 composite artificial vertebral body combined with plate instrumentation. Neurological function was followed up by improvement rate of Frankel and situations of the supporting body was observed by X ray and 3D-CT in 3, 12, 24 months postoperatively. The intervertebral height, physical arc (reflected by Cobb angle) and the locations and fusion rate of the supporting body were assessed in order to evaluate the stability of the cervical spine and alignment improvements., Results: All the patients underwent operation successfully and were followed up for 6 to 24 months with an average of 12 months. The preoperative symptoms were improved to varying degrees. Imaging studies showed that in all cases graft fusion were achieved, and cervical alignments, intervertebral height, cervical spine stability and the locations of the artificial vertebral body were well maintained. No displacement and subsidence of the artificial vertebral body occurred. Postoperative immediate intervertebral height (2.4 ± 0.2) cm, preoperative intervertebral height (1.9 ± 0.1) cm, comparisons of the two groups was statistically significant (q = 2.48, P < 0.001). The immediate, 3 month, 1 year, 2 year period follow-up group intervertebral height was not statistically significant (P > 0.05). Preoperative Cobb angle was 9.8° ± 1.2°, postoperative immediate Cobb angle was 16.6° ± 1.2°, comparisons of the two groups was statistically significant (q = 14.25, P < 0.001). The immediate, 3 month, 1 year, 2 year period follow-up group Cobb angle was not statistically significant (P > 0.05)., Conclusions: n-HA/PA66 artificial vertebral body can provide early cervical spine support and stability and effectively maintain the biological alignment and cervical intervertebral height. It has high rate of graft fusion and is convenient to observe by X-ray. Therefore, n-HA/PA66 can be taken as an ideal graft for anterior lower cervical spine fracture and dislocation operation, but further follow-up study is still required to evaluate the long-term effects.

Objective: To investigate the change in distribution of pathogens and nosocomial antibiotic resistant Gram-negative Bacilli infection in intensive care units one month after an earthquake., Methods: A retrospective survey on the distribution of nosocomial Gram-negative bacilli infection in intensive care units before and one month after the Wenchuan Earthquake was conducted in the West China Hospital. MicroScan Walkaway 96SI or PHOENIX 100 Automatic System in combined with manual identification, was employed to identify the Gram-negative bacilli infection and antibiotic resistance., Results: The proportion of wound infection increased from 7.9% to 20.2% one month after the earthquake, but infection in respiratory tract stayed the most common infection. The common pathogens included Acinetobacter spp. (36.2%), Pseudomonas aeruginosa (22.7%), and Klebsiella spp. (12.3%) before the earthquake. One month after the earthquake, Imipenem remained highly sensitive against Escherichia coli and Klebsiella. spp., while their resistance to ceftazidime increased. Amikacin became the most sensitive antibiotics against Pseudomonas aeruginosa. Acinetobacter spp. had increased resistance to imipenem, but was highly sensitive to gatifloxacin and cefoxitin. The prevalence of extended spectrum beta-lactamases (ESBLs) in Klebsiella spp. and Escherichia coli increased from 52.6% and 48.8% before the earthquake to 55.0% and 87.5% one month after the earthquake, respectively., Conclusion: There is a significant change in distribution of pathogens and nosocomial antibiotic resistant Gram-negative Bacilli infection in intensive care units one month after the Earthquake, which might be associated with a sudden increase in injured patients. It is essential to regularly monitor the resistant rate of bacilli to antibiotics.

Objective: To observe the expression of Bcl-2 and Bax proteins in rat's myocardial cells after Macleaya cordata alkaloids poisoning, and to provide certain molecular biology references for the detection of Macleaya cordata alkaloids poisoning., Methods: Experimental model of Macleaya cordata alkaloids poisoning was established, the expression levels of Bcl-2 and Bax proteins in these cells were detected by immunohistochemistry, and the results were analyzed by computer image system., Results: The expression levels of Bcl-2 and Bax proteins in myocardial cells in poisoning groups were much greater than those in the control groups (P<0.05)., Conclusion: If the clinical symptoms may not be obvious, the detection of Bcl-2 and Bax proteins level by immunohistochemistry still could be ancillary method.

Objective: To retrospectively analysis the treatment characteristics of the systemic situation in patients with crush syndrome after Wenchuan earthquake happened in May 12th, 2008., Methods: Forty-nine patients with crush syndrome and subsequent acute renal failure (ARF) due to the earthquake were treated in West China Hospital. All of patients had been rescued from buildings that collapsed in Wenchuan earthquake. The major associated injuries were in the low extremities and upper extremities. 49 patients developed ARF with increased concentrations of serum creatinine (mean 64 022 U/L) had underwent haemodialysis. Hyperkalaemia was seen in 9 patients and four of them underwent haemodialysis. 49 patients were administered hemodialysis., Results: No patient died. All patients who suffered from the ARF were weaned from hemodialysis after admitted 7 to 35 days. Forty-five extremities underwent amputations and 52 extremities had fasciotomy., Conclusions: Crush syndrome requires urgent recognition and prompt surgical treatment with simultaneous measures to control hyperkalemia and ARF. The authors believe that immediate intensive care therapy and multi-subjective coordination would have improved the survival rate.

Objective: To review the recent research progress of bone-marrow stromal stem cells (BMSCs) in the conditions of culture in vitro, chondrogenic differentiation, and the application in cartilage tissue engineering., Methods: Recent original articles related to such aspects of BMSCs were reviewed extensively., Results: BMSCs are easy to be isolated and cultivated. In the process of chondrogenesis of BMSCs, the special factors and interaction between cells are investigated extensively. BMSCs have been identified to form cartilage in vivo. One theory is the committed chondrocyte from BMSCs is only a transient stage., Conclusion: BMSCs are the alternative seeding cells for cartilage tissue engineering. The conditions promoting mature chondrocyte should be further investigated.