人类活动与卫宁平原土地沙漠化的历史演进

卫宁平原土地沙漠化的出现,最迟不会晚于北周时期,这由卫宁平原腹地鸣沙镇的得名即可证之。宋夏时期,卫宁平原土地沙漠化进一步扩大了,其西部的中卫已出现了沙山,而东部也在七百里瀚海的边缘。明清时期,由于人口的压力,在连山头地角的闲田都加以开垦的情况下,卫宁平原土地沙漠化更加剧了。当今,要治理土地沙漠化,只有植树种草,加大林、牧业的比重,把农、林、牧的结构调整好。     

桉树微量元素营养功能研究

1998— 1999年在广东省雷州半岛进行了桉树微肥施用试验 ,并对桉树微量元素营养功能通过化学分析和生物统计进行了研究 .结果表明 :尾叶桉叶片不同种类微量元素间大多有显著的正相关性 ,与磷、钾、钙、镁等大中量元素含量也呈显著的正相关 .刚果桉叶片不同种类微量元素间大多无显著的相关性 ,与磷、钾、钙、镁等大中量元素间大多也无显著性相关 ,但刚果桉叶片铁、铜、锰等微量元素营养与氮素呈显著性正相关 ,对促进氮素营养的吸收有一定积极影响 .叶片微量元素含量与桉树材积均有显著的正相关和二次回归表达式的关系 ,但树种差异对微肥施用效果有一定影响 .在尾叶桉上 ,施用不同种类的微肥效果相对均衡 ,材积增长量大致相当 ,但随着桉树生长年限的增加 ,微肥施用效果有增强趋势 .微肥施用当年对刚果桉生长有较大的促进作用 ,刚果桉施硼微肥效果要明显好于铜、锌、铁、锰、钼等微肥 ,但随着桉树生长期的延长 ,微肥施用效果并未增强 .     

CsA对LPS诱导的子宫内膜基质细胞中IL-1β和IL-6表达的影响

本研究旨在探索免疫抑制剂环孢菌素A（CsA）对LPS诱导的子宫内膜基质细胞中促炎症细胞因子白细胞介素1β（IL-1β）和白细胞介素6（IL-6）表达的影响。母兔子宫内膜基质细胞经过体外培养和鉴定后,用1 μg/mL脂多糖（lipopolysaccharide,LPS）诱导构建子宫内膜基质细胞炎症模型,0 μg/mL LPS处理作对照组。用0、50、100、200和500 ng/mL CsA处理后,分别检测IL-1β和IL-6的表达水平。结果显示,与对照组相比,添加LPS显著诱导IL-1β和IL-6在子宫内膜基质细胞中的表达（P<0.05）,CsA对子宫内膜基质细胞IL-1β和IL-6的表达无影响,但50、100、200和500 ng/mL CsA均极显著地抑制1 μg/mL LPS诱导的IL-1β和IL-6表达的上调（P<0.01）。因此,在子宫内膜基质细胞中,一定剂量的CsA能够有效抑制LPS诱导的子宫内膜基质细胞的免疫应激。本研究为雌性生殖道遭受革兰氏阴性菌感染引起免疫应激后用CsA治疗的可行性提供了依据,但在临床上的应用及其机制尚需进行深入研究。     

Benches,fountains and trees: Using mixed-methods with questionnaire and smartphone data to design urban green spaces

Smartphones can help researchers track how people use green spaces and understand how design features impact their behaviors. However, when using this data to evaluate green space designs, researchers should be aware of human perceptions of the features within these environments. We contribute a mixed method approach that allows for comparison between how people report using green space features intended to support wellbeing, with how often they are used in common daily routines. As an illustration of this approach, we present the results of a case study conducted on a university campus that compares how outdoor design features are used by students with how these features are reported as being used. Specifically, we compare perceptions of 362 students about which campus design features create a sense of wellbeing, and which are near locations they report using, with the use of these features recorded by the smartphones of a separate group of 62 students. We found that there were large differences between locations students reported using, and locations tracked students used regularly. Features that were used more often during daily routines (low walls, food retail outlets), did not match features reported as helping create a sense of wellbeing in the questionnaire (benches, trees, and sunshine). Of all the design features we modeled, only water features were positively associated with use in the tracking data and supportive of wellbeing in the questionnaire data. Our findings point to the importance of using tracking data together with response data from questionnaires in mixed-method studies if designers want to locate features that the public consider as supportive to their wellbeing, in locations that will be regularly used.     

The Effectiveness of Coxiella burnetii Vaccines in Occupationally Exposed Populations: A Systematic Review and Meta‐Analysis

To estimate the effect of vaccination in preventing acute Q fever in individuals occupationally exposed to Coxiella burnetii, a systematic review and meta‐analysis were undertaken in controlled trials and observational studies. Publications were obtained through a scoping study of English and non‐English articles, and those reporting a commercially licensed or licensable vaccine compared with an unvaccinated or placebo control group were included in the review. Two authors performed independent assessment of risk of systematic error and data extraction. One controlled trial and five cohort publications met the inclusion criteria. All trials used a Henzerling phase I vaccine. A random‐effects meta‐analysis estimated significant protection in abattoir workers (RR = 0.07; 95% confidence interval [CI] 0.02–0.22) compared with the control individuals. In individuals with rare or sporadic contact with the abattoir, a significant benefit of vaccination was also found (RR = 0.06; 95% CI 0–0.93). Overall, the vaccine effectively prevented acute Q fever in individuals responsible for handling animals or their products and those working in the abattoir but not directly exposed to animals (RR = 0.06; 95% CI 0.02–0.18). Caution must be taken when interpreting the effect of C. burnetii vaccination as significant heterogeneity amongst publications was observed. A meta‐regression found no significant univariate associations. This may reflect the uncertainty provided by reported data in the cohort publications. Potential systematic biases were present in the publications, and evidence included may not be sufficiently robust to extrapolate the effect of vaccination on occupationally exposed groups beyond the population of abattoir employees in Australia where all included studies occurred.     

Ag85B lentivirus inhibits expression of TSLP and TSLP receptor in human bronchial epithelial cells

AIM: To investigate the effect of Mycobacterium tubeculosisantigen （Ag85B） lentivirus on the expression of thymic stromal lymphopoietin (TSLP) and TSLP receptor (TSLPR) in cultured normal human bronchial epithelial cells (NHBEC) in vitro. METHODS: Ag85Bgene was subcloned into 293T cells with recombinant plasmid to yield the Ag85B lentivirus. The NHBEC were cultured and transfected with Ag85B lentivirus, NS control and empty lentivirus control using Lipofectamine 2000. The expression of Ag85B, TSLP and TSLPR in NHBEC at mRNA and protein levels was confirmed by real-time PCR and Western blotting.RESULTS: Ag85B lentivirus was constructed with a viral titer of 2×1011 TU/L and the Ag85B expression was detected. As compared with control group and empty lentivirus group, the mRNA expression of TSLP in Ag85B lentivirus group was found to slightly decreased, and the mRNA expression of TSLPR and the protein expression of TSLP and TSLPR were significantly decreased in Ag85B lentivirus group (P<0.05). CONCLUSION: The constructed Ag85B lentivirus antagonizes the expression of TSLP and TSLPR in cultured NHBEC, suggesting that Ag85B inhibits the initiation of asthmatic inflammation by blockage of TSLP-TSLPR pathway.     

Monitoring of spatial variations of particulate matter (PM) pollution through bio-magnetic aspects of roadside plant leaves in an Indo-Burma hot spot region

Particulate matter (PM) is an important air pollutant because of its adverse impacts towards human health. The existing and conventional methods of PMs monitoring are found to be inadequate in feasibility, which paved the way of magnetic biomonitoring approach. The magnetic measurement carried through the plant leaves is useful means in assessing the PM pollution. Plant species are found to be an effective biomonitors and may act as natural filters by trapping and retaining the PM on their leaf surfaces. Therefore, the aim of this communication is to demonstrate the magnetic properties [magnetic susceptibility (χ), anhysteretic remanent magnetization (ARM) and saturation isothermal remanent magnetization (SIRM)] of two roadside plant leaves (Hibiscus rosa-sinensis and Mangifera indica) at four spatially distant sites. The study measures and compares the capabilities of these plants to accumulate and retain the PMs. The study also assesses the PM pollution at selected sites and establishes the relationship between magnetic properties and PM in the city of an Indo-Burma hot spot region. The results indicated a significant correlation between the concentration of ambient PM and magnetic measurement (χ, ARM and SIRM) of both the roadside plant leaves. Similarly, reasonably good correlations are obtained between magnetic parameters (χ, ARM and SIRM) and Fe content in PMs. Present study is, perhaps, a novel contribution in the area of bio-magnetic monitoring studied with several magnetic parameters viz., χ, ARM and SIRM. Results indicated that the bio-magnetic monitoring is applied for environmental geomagnetism which act as proxy for ambient PM pollution and further employed as an eco-sustainable tool for environmental management in urban and peri-urban regions.     

猪IL-2对pcDNA—E39．VP2真核共表达质粒免疫原性的影响

为了研究猪IL-2基因的真核质粒和融合基因形式对pcDNA—E39．VP2真核共表达质粒的免疫增强作用,分别将IL-2基因插入pcDNA3．1（＋）和pcDNA—E39．VP2（已构建）中构建重组质粒pcDNA-IL2和pcDNA-IL2-E39．VP2。将真核质粒pcDNA-IL2-E39．VP2免疫小鼠,另外,将pcDNA—IL2分别先于和后于pcDNA-E39．VP23d免疫小鼠,同时设pcDNA-E39．VP2对照组。对免疫小鼠进行PPV（JEV）抗体水平、脾脏淋巴细胞增殖功能和外周血T淋巴细胞亚群变化的检测。结果显示,1周后,pcDNA-IL2-E39．VP2免疫组和pcDNA—IL2后于pcDNA—E39．VP注射的免疫组JEV／PPV抗体水平和脾脏淋巴细胞增殖活性显著（P〈0．05）或极显著（P〈0．01）高于对照组,pcDNA-IL2先于pcDNA—E39．VP注射的免疫组仅在第5周显著（P〈0．05）高于对照组;各组（除对照组外）CD8^＋值差异不显著（P〉0．05）,CD4^＋、CD4／cD8值都高于对照组,其中pcDNA-IL2-E39．VP2免疫组与对照组差异极显著（P〈0．01）。结果表明,IL-2能增强pcDNA-E39．VP诱导小鼠的免疫能力,且以融合基因形式构建的真核质粒免疫增强效果最明显。     

猪肌肉生长抑制素基因启动子的克隆与鉴定

利用PCR方法从猪基因组DNA中扩增了1.2 kb的肌肉生长抑制素(myostatin)基因启动子序列。并进一步以绿色荧光蛋白(GFP)为报告基因,构建了真核表达载体MSTNPro-EGFP;通过转染C2C12小鼠骨骼肌成肌细胞和猪成纤维细胞,对猪myostatin基因启动子的转录调控活性进行鉴定。结果表明:猪myostatin基因启动子可以启动GFP在C2C12细胞中的转录和表达,而将猪MSTNPro-EGFP载体转染猪胎儿成纤维细胞后并未观察到GFP的表达,说明myostatin基因表达的肌肉特异性源于启动子的转录特异性。