Activation of polyamine catabolism promotes glutamine metabolism and creates a targetable vulnerability in lung cancer.

Polyamines are a class of small polycationic alkylamines that play essential roles in both normal and cancer cell growth. Polyamine metabolism is frequently dysregulated and considered a therapeutic target in cancer. However, targeting polyamine metabolism as monotherapy often exhibits limited efficacy, and the underlying mechanisms are incompletely understood. Here we report that activation of polyamine catabolism promotes glutamine metabolism, leading to a targetable vulnerability in lung cancer. Genetic and pharmacological activation of spermidine/spermine N1-acetyltransferase 1 (SAT1), the rate-limiting enzyme of polyamine catabolism, enhances the conversion of glutamine to glutamate and subsequent glutathione (GSH) synthesis. This metabolic rewiring ameliorates oxidative stress to support lung cancer cell proliferation and survival. Simultaneous glutamine limitation and SAT1 activation result in ROS accumulation, growth inhibition, and cell death. Importantly, pharmacological inhibition of either one of glutamine transport, glutaminase, or GSH biosynthesis in combination with activation of polyamine catabolism synergistically suppresses lung cancer cell growth and xenograft tumor formation. Together, this study unveils a previously unappreciated functional interconnection between polyamine catabolism and glutamine metabolism and establishes cotargeting strategies as potential therapeutics in lung cancer.

Effect of Wenyang Zhenshuai Granules on autophagy and apoptosis of myocardial cells in septic rats via regulating miR-132-3p/UCP2 expression / 中国中药杂志

This study aimed to investigate the effect of Wenyang Zhenshuai Granules(WYZSG) on autophagy and apoptosis of myocardial cells in rats with sepsis via regulating the expression of microRNA-132-3p(miR-132-3p)/uncoupling protein 2(UCP2). Sixty SD rats were randomly divided into modeling group(n=50) and sham operation group(n=10). The sepsis rat model was constructed by cecal ligation and perforation in the modeling group. The successfully modeled rats were randomly divided into WYZSG low-, medium-and high-dose groups, model group and positive control group. Rats in the sham operation group underwent opening and cecum division but without perforation and ligation. Hematoxylin-eosin(HE) staining was used to observe the pathological changes of rat myocardial tissue. Myocardial cell apoptosis was detected by TdT-mediated dUTP nick end labeling(TUNEL) assay. Real-time quantitative polymerase chain reaction(RT-qPCR) was performed to detect the expression of miR-132-3p and the mRNA expressions of UCP2, microtubule-associated protein light chain 3(LC3-Ⅱ/LC3-Ⅰ), Beclin-1 and caspase-3 in rat myocardial tissue. The protein expressions of UCP2, LC3-Ⅱ/LC3-Ⅰ, Beclin-1 and caspase-3 in myocardial tissue were detected by Western blot. Dual luciferase reporter assay was used to verify the regulatory relationship between miR-132-3p and UCP2. The myocardial fibers of sepsis model rats were disordered, and there were obvious inflammatory cell infiltration as well as myocardial cell edema and necrosis. With the increase of the WYZSG dose, the histopathological changes of myocardium were improved to varying degrees. Compared with the conditions in the sham operation group, the survival rate and left ventricular ejection fraction(LVEF) of rats in the model group, positive control group and WYZSG low-, medium-and high-dose groups were decreased, and the myocardial injury score and apoptosis rate were increased. Compared with the model group, the positive control group and WYZSG low-, medium-and high-dose groups had elevated survival rate and LVEF, and lowered myocardial injury score and apoptosis rate. The expression of miR-132-3p and the mRNA and protein expressions of UCP2 in myocardial tissue in the model group, positive control group and WYZSG low-, medium-and high-dose groups were lower, while the mRNA and protein expressions of LC3-Ⅱ/LC3-Ⅰ, Beclin-1 and caspase-3 were higher than those in the sham operation group. Compared with model group, the positive control group and the WYZSG low-, medium-and high-dose groups had an up-regulation in the expression of miR-132-3p and the mRNA and protein expressions of UCP2, while a down-regulation in the mRNA and protein expressions of LC3-Ⅱ/LC3-Ⅰ, Beclin-1 and caspase-3. WYZSG inhibited excessive autophagy and apoptosis of myocardial cells in septic rats and improved myocardial injury, possibly by regulating the expression of miR-132-3p/UCP2.

Application and practice of multidimensional teaching method in "Cell Engineering" / 生物工程学报

In order to improve the teaching quality of engineering courses, we introduced a multi-dimensional teaching method into the teaching reform of biology majors in colleges based on the portfolio assessment in the curriculum of Cell Engineering. We reformed the knowledge system, teaching form and implementation scheme of this course. By combining the reform of online teaching, interactive teaching, case teaching and other teaching modes, the students mastered the relevant professional knowledge and the scientific and technological frontier of Cell Engineering. Moreover, their learning interest and enthusiasm, ability of analyzing and solving professional problems related to Cell Engineering also improved. The implementation of teaching reform of this course provides a reference for other similar professional courses in colleges.

Design and practice of the course of "Biochemical Engineering Experiment" under the context of "Emerging Engineering Education" / 生物工程学报

"Biochemical Engineering Experiment" is a compulsory curriculum for the concentrated practical teaching of biotechnology majors in Hunan University of Science and Engineering. It is also an experimental curriculum for improving the overall quality of bioengineering students under the context of "Emerging Engineering Education". The course includes comprehensive experiments and designable experiments, and the contents of which are designed by combining the local characteristic resources of Yongzhou, the research platform and the characteristics of the talents with engineering background. In the teaching practice, methods such as heuristic teaching, research cases-embedded teaching and interactive teaching are comprehensively used to boost students' interest in learning and stimulate their innovative thinking and application capability. Through curriculum examination and post-class investigation, it was found that the students' abilities of knowledge transfer and application were significantly improved, and they achieved excellent performances in discipline competitions and approved project proposals. The practice and continuous improvement of this course may facilitate fostering high-level innovative and application-oriented talents of biotechnology majors.

Analysis on incidence of occupational diseases in Guangzhou from 2010 to 2020 / 中华劳动卫生职业病杂志

Objective: To analyze the incidence characteristics of occupational diseases in Guangzhou from 2010 to 2020, provide scientific basis for formulating occupational disease prevention and control policies. Methods: In January 2021, based on the data of occupational diseases in Guangzhou reported in the Information Monitoring System of Occupational Diseases and Occupational Health, descriptive epidemiological method was used to analyze the types and characteristics of occupational diseases in Guangzhou from 2010 to 2020. Results: A total of 1341 cases of 38 kinds of occupational diseases in 9 categories were reported in the past 11 years. The incidence of occupational pneumoconiosis, occupational otolaryngology and oral diseases and occupational chemical poisoning ranked the top three, accounting for 38.1% (511/1341) , 30.5% (409/1341) and 16.2% (217/1341) of the total cases respectively. The cases of pneumoconiosis in welders and silicosis accounted for 47.7% (244/511) and 34.4% (176/511) of the cases of occupational pneumoconiosis respectively. The cases of noise deafness accounted for 99.8% (408/409) of occupational otorhinolaryngology oral diseases. Acute occupational chemical poisoning cases accounted for 26.7% (58/217) of the occupational chemical poisoning cases, in which dichloroethane poisoning cases ranked the first, accounting for 79.3% (46/58) . Chronic occupational chemical poisoning cases accounted for 73.3% (159/217) of the occupational poisoning cases, in which benzene and lead poisoning cases ranked the top two, accounting for 79.2% (126/159) and 17.6% (28/159) respectively. Conclusion: Pneumoconiosis, silicosis, noise deafness, benzene poisoning, lead poisoning, dichloroethane poisoning should be supervised and managed as key occupational diseases in Guangzhou.

Innovation and Practice of Biochemistry Course Teaching under the Background of "Golden Course" / 中国生物化学与分子生物学报

There are a series of deficiencies in traditional courses teaching, such as outdated teaching ideas and objectives, insufficient teaching ability and resources, low degree of information technology integration, limited space and time in classroom and knowledge in textbooks, and ignoring the cultivation of students' ideological and political literacy and comprehensive ability. Our biochemistry teaching team promoted an all-round curriculum reform from the aspects of the teaching concept and goal, charm and ability, platform and resource, knowledge system, teaching time and space, teaching mode, ideological and political education, and achievement evaluation system. By establishing " all-around cultivation, student-centered, outcome-based, open & sharing" teaching ideas, improving team charm and ability, enriching high quality of curriculum platform and resources, building a new ideological and political cultivation model of "teaching + research h+ practice", a new "3+X" compound knowledge system, a new teaching model integrated ideological and political cultivation, a multi-dimensional processing evaluation system, the course of biochemistry highlights the typical characteristics of "first-class course", which are high-level, innovation and challenge. Our course has been recognized as a national first-class course and provincial model course of ideological and political cultivation. As a result, students' ideological and political literacy, course performance and comprehensive ability improved significantly. The reform and innovation of curriculum teaching have realized the organic synergy of value shaping, knowledge imparting and ability training.

Immunogenicity and safety levels of inactivated quadrivalent influenza vaccine in healthy adults via meta-analysis.

Objective: The aim of the current study was to evaluate immunogenicity and safety levels of human inactivated quadrivalent influenza vaccine (QIV) which includes two A strains (A/H1N1, A/H3N2) and two B lineages (B/Victoria, B/Yamagata) in healthy adults via meta-analysis. Methods: Searches were conducted in PubMed, Cochrane Library, ClinicalTrials.gov, and EMBASE databases published in 2011-2020 according to inclusion and exclusion criteria. The purpose was to collect and perform meta-analysis of related randomized clinical trial (RCT) data concerning safety and immunogenicity levels of human QIV compared with inactivated trivalent influenza vaccine (TIV). Results: A total of 9 literatures were included. There was no significant difference in the seroconversion(SCR) and seroprotection(SPR) between QIV and TIV for influenza A strains (A/H1N1, A/H3N2) and the B lineage included in the TIV. QIV showed superior efficacy for the B lineage not included in the TIV: SCR RR of 2.20 (95%CI: 1.44-3.37, p = .0003) and SPR RR of 1.34 (95%CI: 1.10-1.63, p = .004) for B/Victoria, and SCR RR of 1.88 (95%CI: 1.53-2.31, p < .00001) and SPR RR of 1.11 (95%CI: 1.03-1.19, p = .006) for B/Yamagata, respectively. There were no significant differences between QIV and TIV for local and systemic adverse events(AE) post-vaccination. Conclusion: In adults 18-64 years old, QIV not only produced similar immunogenicity and safety levels to TIV, but also had better immunogenicity against influenza B vaccine strains not included in TIV.

Astrocytes in depression and Alzheimer's disease / 医学前沿

Astrocytes are an abundant subgroup of cells in the central nervous system (CNS) that play a critical role in controlling neuronal circuits involved in emotion, learning, and memory. In clinical cases, multiple chronic brain diseases may cause psychosocial and cognitive impairment, such as depression and Alzheimer's disease (AD). For years, complex pathological conditions driven by depression and AD have been widely perceived to contribute to a high risk of disability, resulting in gradual loss of self-care ability, lower life qualities, and vast burden on human society. Interestingly, correlational research on depression and AD has shown that depression might be a prodrome of progressive degenerative neurological disease. As a kind of multifunctional glial cell in the CNS, astrocytes maintain physiological function via supporting neuronal cells, modulating pathologic niche, and regulating energy metabolism. Mounting evidence has shown that astrocytic dysfunction is involved in the progression of depression and AD. We herein review the current findings on the roles and mechanisms of astrocytes in the development of depression and AD, with an implication of potential therapeutic avenue for these diseases by targeting astrocytes.

Promoting teaching quality by portfolio assessment in Cell Engineering classroom / 生物工程学报

We introduce the portfolio assessment into the classroom teaching reform in the curriculum of Cell Engineering, a specialty course in bioengineering & biotechnology. We established a complete classroom evaluation system that was divided the classroom assessment system of portfolio into four stages including the preparation stage, training stage, implementation stage and exhibition stage. We also discuss the feasibility and necessity of implementing the portfolio evaluation method in the course of cell engineering, the construction of evaluation system, and the key points and matters needing attention in the implementation process. The classroom reform is very productive, not only the classroom atmosphere has been activated, students' learning initiative and autonomy has been enhanced, but also the students' ability to analyze and solve professional problems related to cell engineering technology has been improved. The implementation of classroom teaching reform of this course can provide reference for other similar professional courses in colleges and universities.

Transurethral resection of the prostate is an independent risk factor for biochemical recurrence after radical prostatectomy for prostate cancer / 亚洲男科学杂志(英文版)

Biochemical recurrence (BCR) is important for measuring the oncological outcomes of patients who undergo radical prostatectomy (RP). Whether transurethral resection of the prostate (TURP) has negative postoperative effects on oncological outcomes remains controversial. The primary aim of our retrospective study was to determine whether a history of TURP could affect the postoperative BCR rate. We retrospectively reviewed patients with prostate cancer (PCa) who had undergone RP between January 2009 and October 2017. Clinical data on age, prostate volume, serum prostate-specific antigen levels (PSA), biopsy Gleason score (GS), metastasis stage (TNM), D'Amico classification, and American Society of Anesthesiologists (ASA) classification were collected. Statistical analyses including Cox proportional hazard models and sensitivity analyses which included propensity score matching, were performed, and the inverse-probability-of-treatment-weighted estimator and standardized mortality ratio-weighted estimator were determined. We included 1083 patients, of which 118 had a history of TURP. Before matching, the non-TURP group differed from the TURP group with respect to GS (P= 0.047), prostate volume (mean: 45.19 vs 36.00 ml, P < 0.001), and PSA level (mean: 29.41 vs 15.11 ng ml-1, P= 0.001). After adjusting for age, PSA level, T stage, N stage, M stage, and GS, the TURP group showed higher risk of BCR (hazard ratio [HR]: 2.27, 95% confidence interval [CI]: 1.13-3.94, P= 0.004). After matching (ratio 1:4), patients who underwent TURP were still more likely to develop BCR according to the adjusted propensity score (HR: 2.00, 95% CI: 1.05-3.79, P= 0.034). Among patients with PCa, those with a history of TURP were more likely to develop BCR after RP.

A simple and safe antibody neutralization assay based on polio pseudoviruses.

The evaluation of the immunogenicity of Sabin strain based Inactivated Poliovirus Vaccines (sIPV) necessitates the use of wild strains in neutralization assays to assess the potential cross-reactivity of antibodies. The live virus strains including wild and Sabin strains must be handled in level 3 biocontainment laboratories. To develop an alternative assay without the use of a live virus, we constructed Mahoney, MEF-1, and Saukett pseudovirions by inserting luciferase reporter genes into intact capsid proteins. Afterward, we developed a pseudovirus-based neutralization test (pNT) and evaluated for the specificity and reproducibility. We tested serum samples from a clinical trial on sIPV vaccines by pNT and compared the results with those obtained from conventional neutralization tests (cNT). A strong correlation was observed between two methods, with the correlation coefficients of all three types of IPV vaccines being greater than 0.82 (p < 0.0001). The Geometric Mean Titer (GMT) values obtained by pNT were approximately four times higher than that by cNT, revealing the better sensitivity of pNT. In conclusion, pNT is a safe, rapid and sensitive quantitative assay with the potential of being an alternative for the evaluation of the potency of polio vaccines.

Expression of CXCR family proteins in different subtypes of breast cancer and their clinical prognosis / 实用肿瘤学杂志

Objective The aims of this study were to determine the expression of CXCR family proteins in various subtypes and adjacent tissues of breast cancer and its relationship with prognosis,and to provide a reference for clinical diagnosis,treatment and prognosis of breast cancer. Methods The mRNA expressive profiles of CXCR family proteins in paracancerous tissues and different subtypes of breast cancer tissues were obtained from the TCGA(The Cancer Genome Atlas)database. The prognostic survival analysis of each differentially expressed protein was obtained using the PRECOG website. Results Except for CXCR1,the expression of CX-CR family proteins in breast cancer tissues and adjacent tissues was statistically different( P<0. 05). CXCR2P1,CXCR3,CXCR4, CXCR5 and CXCR6 were highly expressed in breast cancer tissues,CXCR2 and CXCR7 were lowly expressed in breast cancer tis-sues. The expressive levels of CXCR3,CXCR4 and CXCR7 were associated with the prognosis of patients. Conclusion The expres-sions of CXCR3,CXCR4 and CXCR7 in breast cancer tissues and adjacent tissues is significantly different,and its expression is related to the prognosis of breast cancer patients,which may be a potential target for molecular diagnosis or targeted therapy of breast cancer.

Exploration of the Role of Tumor Suppressor Genes Foxo1 and PTEN in the Tumorigenesis of Mouse Natural Killer-Cell Lymphoma / 中国实验血液学杂志

OBJECTIVE@#To explore whether tumor suppressor gene Foxo1 and PTEN play a critical role in the tumorigenesis of mouse natural killer-cell lymphoma.@*METHODS@#NKp46-iCre mice were crossed with mice carrying floxed Foxo1 alleles (Foxo1) as well as floxed PTEN alleles (PTEN) to generate mice in which Foxo1 and PTEN in NK cells were knock-out, referred as Foxo1PTEN. The growth and development of the mice and tumor formation were observed. The flow cytometry was used to detect the percentages of NK cells in main lymphatic organs. B16F10 metanoma model of tumor metastasis was utilized to investigate NK cell-mediated tumor surveillance in vivo after NK cells special deletion of Foxol and PTEN.@*RESULTS@#The mouse model with NK cell-special Foxo1 and PTEN double knockout was established. Compared with control group (Foxo1PTEN mice), Foxo1PTEN mice were born alive and appeared to be healthy over a period of 46 weeks. No spontaneous tumor formation was observed at this stage. There were no significant differences in NK cell percentages of gated lymphocytes from various organs including blood, bone marrow, peripheral lymph node and spleen between Foxo1PTEN mice and Foxo1PTEN mice [PB: 4.76%±0.46% vs 4.17%±0.64% (P＞0.05, n=8); BM: 1.13%±0.23% vs 1.31%±0.10% (P＞0.05, n=8) ; LN: 0.50%±0.10% vs 0.85%±0.20% (P＞0.05, n=8); SP: 4.41%±0.65% vs 3.50%±0.24% (P＞0.05, n=8)]. B16F10 melanoma metastasis model of tumor was established, No differences in median survival time were observed in the 2 types of mice (P＞0.05, n=13).@*CONCLUSION@#The simultaneous deletion of the Foxo1 and PTEN genes may not plays significant role in the tumorigenesis of mouse natural killer-cell lymphoma and NK cell-mediated tumor surveillance in vivo.

Current status of associating liver partition and portal vein ligation for staged hepatectomy in treatment of liver metastasis of colorectal cancer / 临床肝胆病杂志

At present, radical resection remains the best treatment strategy for liver metastasis of colorectal cancer, and patients with large or multiple tumors often face the problem of insufficient residual liver volume after hepatectomy, which may lead to serious complications including liver failure after surgery. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a novel two-step hepatectomy that allows rapid proliferation of the residual liver after primary surgery and can improve the resectability of liver tumors and reduce the risk of postoperative liver failure. Although ALPPS can achieve R0 resection or tumors and prolong patients’ survival time, there are still controversies over its application due to high incidence rates of complications and mortality rate. With reference to related studies in China and foreign countries, this article reviews the current application status and clinical value of ALPPS in liver metastasis of colorectal cancer.

Bioabsorbable Drug-Eluting Stent Versus Bare Metal Stent in Iliac Artery Evaluated by Optical Coherence Tomography: An In Vivo Study in Porcine.

OBJECTIVE: This study aimed to compare, using optical coherence tomography (OCT), the outcomes of bioabsorbable drug-eluting stent with those of bare metal stent (BMS) following implantation in porcine iliac artery. METHODS: After the placement of BMS and bioabsorbable drug-eluting stents, we used OCT and digital subtraction angiography to investigate stent appositions, arterial neointima, evagination, and restenosis at 1 and 3 months. RESULTS: At 1 and 3 months after stent implantation, OCT study was performed to investigate 32 stents and 21 788 struts. Thirty-three malapposed struts were found in the bioabsorbable drug-eluting stent groups and 2 were found in BMS groups. The average neointimal thickness, area, and in-stent stenosis were significantly lower in bioabsorbable drug-eluting stents than in BMS, while the frequency of malapposed struts was higher in the bioresorbable drug-eluting stent groups. Average neointimal thickness was lower in bioabsorbable drug-eluting stents than in BMS at 1 (0.19 ± 0.09 vs 0.67 ± 0.75 mm; P < .001) and 3 months (0.21 ± 0.08 vs 1.52 ± 0.28 mm; P < .001). CONCLUSION: Our study suggested that bioabsorbable drug-eluting stent is more effective in decreasing arterial restenosis than BMS in animal models.

Quercetin enhances 5-fluorouracil-induced apoptosis in gastric cancer by down-regulating c-Jun expression / 中国病理生理杂志

AIM:To investigate the enhancing effect of quercetin on the 5-fluorouracil-induced apoptosis in gastric cancer.METHODS: MTT assay was conducted to evaluate the effect of quercetin on the 5-fluorouracil-induced death of gastric cancer cell line BGC-823.Co-immunoprecipitation and Western blot analysis were performed to detect the expression of c-Jun and Bcl-xL,phosphorylation of c-Jun,activation of caspase-9 and caspase-3,and release of cytochrome C in BGC-823 cells treated with quercetin and 5-fluorouracil.The apoptosis of BGC-823 cells treated with quercetin and 5-fluorouracil was analyzed by flow cytometry.RESULTS: Adjuvant therapy of quercetin significantly enhanced the 5-fluorouracil-induced death of BGC-823 cells.Meanwhile, quercetin decreased the half maximal inhibitory concentration (IC50)of 5-fluorouracil to BGC-823 cells.Quercetin treatment significantly inhibited the expression of c-Jun,and inhibited the 5-fluorouracil-induced phosphorylation of c-Jun and the interaction between c-Jun and activating transcription factor 2 (ATF2).Subsequently,quercetin inhibited the up-regulation of Bcl-xL induced by 5-fluorouracil in the BGC-823 cells. However,transfection with c-Jun plasmid abolished the promoting effect of quercetin on 5-fluorouracil-induced cell death. In addition, quercetin promoted 5-fluorouracil-induced release of cytochrome C from mitochondria and caspase-dependent apoptosis in BGC-823 cells.CONCLUSION:Quercetin treatment enhances 5-fluorouracil-induced mitochondrial apoptosis in BGC-823 cells through c-Jun/ATF2/Bcl-xL pathway.

Expression and purification of GRIK3 intracellular region protein in prokaryotic cell system / 实用医学杂志

Objective To express and purify GRIK3 intracellular region protein in prokaryotic cell system. Methods The histamine(His)tagged GRIK3 intracellular region recombinant plasmid pCzn1-GRIK3-in-tra was constructed and transformed into Escherichia coli(E.coli). The His-GRIK3-intra recombinant protein was expressed after the induction with IPTG. The target protein was purified by Ni-NTA affinity chromatography column. Results The prokaryotic expression plasmid pCzn1-GRIK3- intra was successfully constructed and the GRIK3 intracellular region protein in E.coli were efficiently expressed after the induction with IPTG. The purified target pro-tein was successfully obtained by Ni-NTA affinity chromatography column. Conclusion The successful construc-tion of prokaryotic expression plasmid expressing GRIK3 intracellular region gene and preparation of high purity GRIK3 intracellular region protein have paved the way for further exploration of the intracellular signal transduction mechanism of membrane protein GRIK3.

Analysis on risk factors constituent in 680 cases of nosocomial infection / 重庆医学

Objective To explore the risk factors of nosocomial infections to provide a reference for prevention and control of nosocomial infection.Methods The data of 680 patients with nosocomial infection in this hospital from January 2015 to December 2016 were retrospectively collected.The characteristics of nosocomial infection were analyzed from the aspects of age,hospitalization department,infection site,etc.Results A total of 680 cases of nosocomial infection accounted for 1.67％(680/40 657) of all hospitalization patients,including 316 cases(nosocomial infection rate was 2.47％) of 61-80 years old.The infection rate was the highest in ICU(24.90％),followed by the nephrology department(4.99％).For infection sites,the maximal cases-times in infection site was lower respiratory tract(413 case-times),followed by urinary tract and superficial incision(each 68 case-times).The pathogenic detection rate was 45.03％,and 190 strains of pathogens were detected.The top five places were Escherichia coli(47 strains),Klebsiella pneumoniae(28 strains),Pseudomonas aeruginosa (23 strains),Staphylococcus aureus (22 strains) and Bauman Acinetobacter (16 strains).Logistic regression analysis showed that age larger than 60 years old,hospitalization time longer than 60 d,indwelling urinary catheter,peripherally inserted central catheter(PICC),tracheotomy and enteral nutrition were the risk factors for nosocomial infection occurrence.Conclusion Hospital should put the emphasis on preventing nosocomial infection of lower respiratory tract and strengthen the nosocomial infection management of key departments like ICU.

Structure-Dependent Optical Properties of Self-Organized Bi2Se3 Nanostructures: From Nanocrystals to Nanoflakes.

Bismuth selenide (Bi2Se3), with a wide bulk band gap and single massless Dirac cone at the surface, is a promising three-dimensional topological insulator. Bi2Se3 possesses gapless surface states and an insulator-like bulk band gap as a new type of quantum matter. Different Bi2Se3 nanostructures were prepared using electron beam evaporation with high production efficiency. Structural investigations by energy-dispersive X-ray analysis, scanning electron microscopy, and X-ray diffraction revealed the sample stoichiometries and the structural transition mechanism from nanocrystals to nanoflakes. The optical properties systematically probed and analyzed by spectroscopic ellipsometry showed strong dependence on the nanostructures and were also predicted to have structure-modifiable technological prospects. The optical parameters, plasma frequencies, scattering rates of the free electrons, and optical band gaps were related to the topological properties of the Bi2Se3 nanostructures via light-matter interactions, offering new opportunities and approaches for studies on topological insulators and spintronics. The high-quality Bi2Se3 nanostructures provide advantages in exploring novel physics and exploiting prospective applications.

Safety and effectiveness assessment of 2011-2012 seasonal influenza vaccine produced in China: a randomized trial.

OBJECTIVE: This study evaluated the effectiveness and safety of the egg-based, trivalent, inactivated split influenza vaccine produced by the Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, China. METHODS: From March 2012 through May 2012, we enrolled a total of 1390 healthy volunteers between the ages of 3 and 80 years in a randomized clinical trial at the Hebei Disease Control Center Vaccine Clinical Evaluation Center. For all subjects, body part adverse reactions and whole-body adverse reactions were observed 30 min, 6 h, and 1-7 days' post-inoculation. If no severe adverse effects were observed 7 days' post-vaccination, the local and systemic reactions of preliminary test participants were recorded until day 28. There was no placebo group in this study. Blood samples were taken for serological testing before vaccination and 28 days' post-vaccination. RESULTS: Twenty-eight days after vaccination, the seroconversion rates of experimental and control groups were H1N1 75.3% and 75.7%, H3N2 75.8% and 71.8%, B 70.7% vs. 69.4%, (P > 0.05). The antibody Geometric Mean Titer（GMT）of experimental and control groups were H1N1 (179.7, 182.4), H3N2 (584.0, 445.7), B (201.4,191.6). The protection rate of experimental and control groups was not statistically significant (H1N1: 86% vs. 87%, H3N2: 99% vs. 98%, B: 98% vs. 98%). Also, 95% confidence intervals of the protection rate difference between the experimental and the control group were H1N1: -0.1% (-4.1,3.8) %, H3N2: 0.3% (-1.0,1.7) % and B: 0.2% (-1.5,1.9) %; confidence intervals exceeded the limit of -5%. The rates of adverse reactions between experimental and control groups were 6.3% and 7.7% in local response reactions, and 19.5% and 18.0% in systemic reactions. Three hundred and twenty-seven adverse events (AEs) in 1200 (27.76%) subjects were reported within 28 d after vaccination. No serious adverse events occurred during the study. CONCLUSIONS: The experimental vaccine three-antibody protection rate was non-inferior to the control vaccine. Our results demonstrated that the experimental vaccine achieved the primary immunogenic end point of the intended clinical protocol, as well as a secondary immunogenic end-point, with an acceptable level of safety. IRB approval for this study was issued under #2012Y0005 and registered as Clinical Trial No. NCT01551810.