Genome Mining of α-Pyrone Natural Products from Ascidian-Derived Fungus Amphichorda felina SYSU-MS7908

Culturing ascidian-derived fungus Amphichorda felina SYSU-MS7908 under standard laboratory conditions mainly yielded meroterpenoid, and nonribosomal peptide-type natural products. We sequenced the genome of Amphichorda felina SYSU-MS7908 and found 56 biosynthetic gene clusters (BGCs) after bioinformatics analysis, suggesting that the majority of those BGCSs are silent. Here we report our genome mining effort on one cryptic BGC by heterologous expression in Aspergillus oryzae NSAR1, and the identification of two new α-pyrone derivatives, amphichopyrone A (1) and B (2), along with a known compound, udagawanone A (3). Anti-inflammatory activities were performed, and amphichopyrone A (1) and B (2) displayed potent anti-inflammatory activity by inhibiting nitric oxide (NO) production in RAW264.7 cells with IC₅₀ values 18.09 ± 4.83 and 7.18 ± 0.93 μM, respectively.     

Effect of acupuncture on sleeping pattern and qualities in chronic insomnia

AIM: To investigate the effects of acupuncture on the sleeping qualities in chronic insomnia patients, and to determine the safety of acupuncture therapy in clinical practice.METHODS: Fifty-six chronic insomnia patients were selected in the study according to the expert consensus of insomnia. Pre and post intervention self-evaluation method was used to evaluate the effects of acupunctural therapy. The selection of acupoints was based on the principles of traditional Chinese medicine. All main points were connected to KWD8081 electro-acupuncture device. All supplemen-tary points were stimulated with reinforcing or reducing needling. The treatment duration lasted for about 30 to 40 min, 10 daily treatment as one complete course. Pittsburgh sleep quality index(PSQI) was used to determine the sleep quality after 4 courses of treatments. Polysomnogram was used to detect the sleeping patterns of the patients. The adverse effects and safety issues of acupuncture were monitored for one month after the last treatment.RESULTS: Acupunctural treatment significantly ameliorated the sleep quality of the patients with chronic insomnia and reduced the frequency of disturbed sleeps(P<0.05). The activities of their daily life were also improved. Moreover, acupuncture also comparatively prolonged the duration of slow wave sleep(SWS), as well as the duration of rapid eye movement sleep(REM). The usage of sleep medications was significantly reduced in both quantity and frequency(P<0.05) after acupuncture. The side effects of sleeping medications such as hangover, addiction and drowsiness(incident rate = 0%) were also significantly decreased. However, the rebound rate of insomnia was 32.14% within a month post acupunctural treatment.CONCLUSION: Acupuncture improves the sleeping pattern and the quality of daily life significantly, prolongs the durations of SWS and REM sleeping, and reduces the use of medications. Acupunctural treatment for chronic insomnia is safe and effective. However, long term efficacy of acupuncture needs to be explored further.     

体外定向诱导小鼠骨髓间充质干细胞分化为神经元样细胞

[目的]分离和克隆小鼠骨髓间充质干细胞,并诱导分化为神经元样细胞。[方法]利用Percoll密度梯度离心的方法进行小鼠骨髓间充质干细胞分离及培养,分别采用β-巯基乙醇和BHA诱导分化为神经元样细胞。用神经元特异性烯醇化酶和神经纤维丝蛋白免疫细胞化学方法对已分化的神经元样细胞进行鉴定和分化率分析。[结果]经2种诱导剂诱导的小鼠骨髓间充质干细胞均出现神经元样细胞的分化,胞体呈神经元状,伸出较长轴突样和树突样突起且有分支。而且免疫细胞化学鉴定显示,诱导分化后的神经元样细胞神经元特异性烯醇化酶染色和神经纤维丝蛋白免疫细胞化学染色均呈阳性,β-巯基乙醇诱导分化细胞表达NSE的阳性率为（86.8±2.7）%;诱导分化细胞表达Neurofilament200 kD的阳性率为（75.2±2.3）%;BHA诱导分化细胞表达NSE的阳性率为（80.5±2.2）%;诱导分化细胞表达Neurofilament200 kD的阳性率为（73.2±1.6）%。[结论]小鼠骨髓间充质干细胞能够在诱导剂β-巯基乙醇和BNA的诱导下体外诱导分化为神经元样细胞。     

ECM-ISC框架下期望确认度对在线知识问答社区持续使用意愿的影响研究

[目的/意义]研究影响用户持续使用在线知识问答社区意向的因素,深入理解用户接受并持续使用技术创新的本质,深化用户持续使用行为理论,促进知识问答社区和用户需求理论的发展。[方法/过程]笔者以“期望—确认”理论模型（ECM-ISC）为基础,结合关系维持双元理论等构建在线知识问答社区的用户持续使用模型和测量量表,共搜集358份有效样本数据,采用结构方程模型进行假设检验。[结果/结论]结果表明,用户的期望确认度由信息、社交、情感、娱乐以及社会认同期望5个维度构成,5种确认度都会正面显著影响用户的满意度和感知有用性;满意度和感知有用性对用户持续使用意愿有积极影响;用户感知转换成本、用户习惯和自我效能正向影响持续使用意愿;自我效能正向影响社会认同确认度。     

中小学图书馆现代化建设的实践与思考

分析了中小学图书馆现代化建设的现状与水平,并以珠海市第三中学图书馆现代化建设为例,从硬件建设和软件建设两方面谈了图书馆现代化建设的一些措施与做法,指出中小学图书馆的现代化建设是一项长期工程,要加强合作与交流,不断深入。     

猪繁殖与呼吸综合征RT-LAMP检测方法研究

应用反转录环介导等温扩增技术(RT-LAMP),利用猪繁殖与呼吸综合征病毒(PRRSV)核衣壳蛋白(N蛋白)ORF7基因保守序列的6个区域设计2对特异引物,经反应体系、反应条件优化及敏感性和特异性试验,建立了PRRSV RT-LAMP检测方法。研究结果表明,该检测方法不需要复杂仪器,仅用一台普通恒温水浴锅,在等温条件(63 ℃)保温1 h,即可完成核酸扩增反应,加入核酸染料SYBR GreenⅠ后,用肉眼即可对试验结果进行准确判定,为田间和基层部门检测猪繁殖与呼吸综合征病毒提供了一种廉价、简便、快速、敏感、特异的新方法。     

珠海园林绿化节水对策研究

通过对珠海市园林绿化用水特点的分析。探讨了园林绿化节水途径,提出了珠海市实施节水园林绿化的一些策略。     

67例下叶基底段肺结核误诊原因分析

目的探讨下叶基底段肺结核误诊的原因,以提高诊断水平,减少误诊率．方法对珠海地区2005年1月～2008年12月登记管理的下叶基底段肺结核67例误诊病例进行回顾性分析．结果误诊为肺炎16例,支气管肺炎31例,肺脓疡8例,肺癌9例,支气管扩张并感染3例．结论下叶基底段肺结核的临床症状、X线表现均不典型,易误诊,应提高对下叶基底段肺结核的认识．全面收集临床资料,充分利用各种检查手段,寻求病原和组织学诊断依据是减少误诊的关键．     

花鲈源杀鱼爱德华菌耐药谱及毒力相关性分析

从广东省珠海市养殖花鲈（基因鉴定出87株杀鱼爱德华菌（）。耐药谱分析显示,杀鱼爱德华菌对利福平（98.85%）、麦迪霉素（96.55%）、红霉素（95.40%）、青霉素（68.96%）、磺胺异恶唑（58.62%）、复方新诺明（28.73%）、阿莫西林（21.83%）、庆大霉素（13.79%）、新霉素（10.34%）、呋喃唑酮（3.45%）、诺氟沙星（2.29%）、氯霉素（2.29%）、多西环素（2.29%）、土霉素（1.15%）、氟苯尼考（1.14%）、恩诺沙星（0%）耐药。杀鱼爱德华菌共有32种耐药谱型且均为多重耐药菌株,多重耐药指数为0.423。斑马鱼致死率结果发现,杀鱼爱德华菌是一株中高毒力菌株;进一步的相关性分析揭示,杀鱼爱德华菌毒力与庆大霉素抗性呈正相关（<0.01）呈负相关。综上所述,花鲈源杀鱼爱德华菌为高毒、多重耐药的菌种,其毒力与耐药性多呈现负相关,推测是由于细菌因获得外源DNA而产生额外的生物成本所致。     

Mangroves of China: a brief review

The distribution, ecology, conservation and management of Chinese mangroves are reviewed. Mangroves naturally occur along the southeast Chinese coast and traverse the provinces of Hainan, Guangdong, Guangxi, Fujian and Taiwan, intermittently extending from 18°N. Thirty-seven mangrove tree species, representing 20 families and 25 genera, have been documented, with thermophilic eurytopic species being the dominant components. A remarkable decrease of species richness is evident from Hainan (18–20°N) to Fujian (23.5–27°N) (35 vs. 9 species). The existing mangrove area is ≈ 17 800 ha, accounting for slightly more than 0.1% of the world's total. Nearly two-thirds of China's mangroves have been lost during the past 40 years, largely due to conversion for rice-farming, embankment for aquaculture ponds and, recently, rapid urban development. A total of 201 papers on Chinese mangroves was published between 1950 and 1995, 178 of which are in Chinese; thus, they are not easily accessible to the international scientific community. Most of the work was conducted after 1985 (91% of the papers published) and research emphasized floristics with little attention to managementrelated issues. The net primary production of the Chinese mangroves shows a latitudinal trend, also significant deviations from predictions on models generated using non-Chinese data. Although 28 Chinese institutions have dealt with mangrove research, only five maintain long-term projects. The bulk of research has been carried out in six mangrove reserves: Qinglan, Dongzhai (Hainan), Mai Po (Hong Kong), Futian (Guangdong), Shankou (Guangxi) and Jiulongjiang (Fujian). Twelve mangrove reserves have been established so far in mainland China, one in Hong Kong (Mai Po) and one in Taiwan (Tanshui). These reserves cover an area of over 19000 ha, of which 8445 ha are mangroves (47% of existing mangrove area). Six measures that can facilitate mangrove conservation and management are recommended: (a) declare more mangrove areas as nature reserves; (b) set up a national mangrove committee and mangrove research centre to foster research and management; (c) develop concrete management guidelines; (d) enact protective legislation and ensure its strict enforcement; (e) launch education programmes in the major mangrove reserves; and (f) stop further nonsustainable exploitation of mangroves and their habitats.