Performance of cardiopulmonary resuscitation during prolonged basic life support in military medical university students: A manikin study

BACKGROUND: The quality of chest compressions can be significantly improved after training of rescuers according to the latest national guidelines of China. However, rescuers may be unable to maintain adequate compression or ventilation throughout a response of average emergency medical services because of increased rescuer fatigue. In the present study, we evaluated the performance of cardiopulmonary resuscitation(CPR) in training of military medical university students during a prolonged basic life support(BLS).METHODS: A 3-hour BLS training was given to 120 military medical university students. Six months after the training, 115 students performed single rescuer BLS on a manikin for 8 minutes. The qualities of chest compressions as well as ventilations were assessed.RESULTS: The average compression depth and rate were 53.7±5.3 mm and 135.1±15.7 compressions per minute respectively. The proportion of chest compressions with appropriate depth was 71.7%±28.4%. The average ventilation volume was 847.2±260.4 m L and the proportion of students with adequate ventilation was 63.5%. Compared with male students, significantly lower compression depth(46.7±4.8 vs. 54.6±4.8 mm, P0.001) and adequate compression rate(35.5%±26.5% vs. 76.1%±25.1%, P0.001) were observed in female students.CONCLUSIONS: CPR was found to be related to gender, body weight, and body mass index of students in this study. The quality of chest compressions was well maintained in male students during 8 minutes of conventional CPR but declined rapidly in female students after 2 minutes according to the latest national guidelines. Physical fitness and rescuer fatigue did not affect the quality of ventilation.     

Incorporation of magnesium ions into photo‐crosslinked alginate hydrogel enhanced cell adhesion ability

Photo‐crosslinked alginate hydrogel attracts wide interest in tissue engineering because of its excellent controllability and stability. However, its highly hydrophilic property makes cell adhesion difficult. Plenty of studies have confirmed that magnesium ions (Mg²⁺) can efficiently improve the attachment of osteoblasts. In this study, for the first time, we fabricated a durable, crosslinked, alginate hydrogel with a dual‐crosslinking network. Photo‐crosslinked alginate hydrogel was chosen as the basic backbone, and various amounts of Mg²⁺ were incorporated into the hydrogel through ionic crosslinking. The results showed that the physicochemical properties of the hydrogels, including surface structure, composition, swelling ratio, ion release and elastic modulus, could be well tuned by controlling the amount of Mg²⁺ incorporated. In addition, a certain amount of Mg²⁺ significantly improved the attachment and spread of osteoblasts on the hydrogels. These characteristics make Mg²⁺‐incorporated photo‐crosslinked alginate hydrogel a promising scaffold for bone tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd.     

Blood donation in China: sustaining efforts and challenges in achieving safety and availability

China has entered a new phase in blood safety and availability through persistent efforts in the past decades. Based on national data from 2008 to 2012, we present a comprehensive review on the blood services ranging from policy and organization, supply, donors, screening and processing, and clinical use to government response in contemporary China. Current evidence suggests that the Chinese blood industries, after continual efforts in reforms on the legal framework and national management system, have been in a relatively steady but bottleneck stage. Although the blood industries have had an impressive track record on management and resolving problems, such as low availability, limited donors, deficient laboratory tests, shortage of blood products, and unnecessary clinical usage of blood still exist nationwide. While medical technology and services have seen a rapid increase in progress in recent years, they have not coordinated with the development of the national health care system. This article presents an analysis with detailed data, rich contents, and recent response from the Chinese government, allowing readers to appreciate how China, a country with more than 19.13% of the world's population, has long endeavored to improve safety and availability of blood. Meantime, the article sincerely welcomes the guidance on policymaking and technical assistance from the international community. Data in this article do not include those of Hong Kong, Macao, or Taiwan.     

Interactions between QnrB,QnrB Mutants,and DNA Gyrase

Plasmid-encoded protein QnrB1 protects DNA gyrase from ciprofloxacin inhibition. Using a bacterial two-hybrid system, we evaluated the physical interactions between wild-type and mutant QnrB1, the GyrA and GyrB gyrase subunits, and a GyrBA fusion protein. The interaction of QnrB1 with GyrB and GyrBA was approximately 10-fold higher than that with GyrA, suggesting that domains of GyrB are important for stabilizing QnrB1 interaction with the holoenzyme. Sub-MICs of ciprofloxacin or nalidixic acid reduced the interactions between QnrB1 and GyrA or GyrBA but produced no reduction in the interaction with GyrB or a quinolone-resistant GyrA:S83L (GyrA with S83L substitution) mutant, suggesting that quinolones and QnrB1 compete for binding to gyrase. Of QnrB1 mutants that reduced quinolone resistance, deletions in the C or N terminus of QnrB1 resulted in a marked decrease in interactions with GyrA but limited or no effect on interactions with GyrB and an intermediate effect on interactions with GyrBA. While deletion of loop B and both loops moderately reduced the interaction signal with GyrA, deletion of loop A resulted in only a small reduction in the interaction with GyrB. The loop A deletion also caused a substantial reduction in interaction with GyrBA, with little effect of loop B and dual-loop deletions. Single-amino-acid loop mutations had little effect on physical interactions except for a Δ105I mutant. Therefore, loops A and B may play key roles in the proper positioning of QnrB1 rather than as determinants of the physical interaction of QnrB1 with gyrase.     

精神分裂症患者凶杀犯罪研究进展

重性精神病以精神分裂症为主,患者受精神症状等多种因素的影响,易发生暴力或凶杀等行为,严重威胁着社会的公共安全,已日益受到社会各界的重视。本文对国内外有关精神分裂症患者凶杀犯罪的研究文献作一综述,为开展精神病患者凶杀研究提供参考。