红皮云杉群体遗传多样的研究

在红皮云杉(Picea korainesis)分布区内,选取了有代表性的长白山及其支脉张广才岭、老爷岭、完达山,小兴安岭,大兴安岭,大兴安岭向内蒙古高原过渡地带以及锡霍特山脉的12个群体,运用群体遗传学、生理遗传学、森林遗传学以及林木育种的理论和方法,利用主成分和分层聚类分析等多种统计分析方法,从表型和分子水平等多层次较为系统地研究了红皮云杉群体内、群体间的变异,同时探讨了各种亲代、后代特征以及等位酶与生态环境因子之间的关系。,首次从亲代生物系统学特征,后代苗木形态、生长、生物量和矿物质元素等对红皮云杉群体遗传变异进行了研究,结果表明,红皮云杉具有丰富的遗传变异,群体内变异大于群体间变异;红皮云杉12个群体11个酶系统21个位点中约有27.2%的基因位点是多态的,群体间的变异量只占总变异量的15.2%,84.8%的变异存在于群体内。红皮云杉群体等位酶多态位点的比率在云杉属中处于较低的水平,群体间的分化与云杉其它树种相比处于较高的水平。等位酶与形态等具有相似的变异趋势。根据红皮云杉气候、亲代及后代特征群体区划结果,我们认为红皮云杉种子区划为:长白山种子区(Ⅰ);老爷岭、张广才岭、完达山种子区(Ⅱ);小兴安岭种子区(Ⅲ);大兴安岭北部种子区(Ⅳ);大兴安岭西南部种子区(Ⅴ);锡霍特山脉种子区(Ⅵ)。     

桉树LH22、U6无性系茎提取液对绿豆插条发根和种子萌发的影响

研究表明,难生根的尾叶桉×赤桉LH₂₂无性系茎的粗提液对绿豆插条发根率、不定根长度有极明显的抑制作用,而易生根的尾叶桉U₆无性系茎的粗提液却没有抑制作用。对这些茎粗提液进一步用有机溶剂萃取分离,各萃取相进行白菜种子萌发的生物测验,表明LH₂₂中的水相、乙醚相含有抑制种子萌发的物质,经Duncan's新复极差法分析抑制作用显著,而易生根的U₆中却无影响。水相、乙醚相分别再经硅胶柱层析技术分离纯化得到多种不同的成分,进行白菜种子萌发生物测验后,有数种成分有明显的抑制作用。因此说明,难生根的LH₂₂无性系茎内含有成分不同的生根抑制物质,而易生根的U₆无性系茎内几乎没有或含有少量这些生根抑制物质。     

中国多辐藻属(Myriactula)三个新记录种

报道中国产粘膜藻科(Leathesiaceae)多辐藻属(Myriactula)三个新记录种:阿拉伯多辐藻(Myriactula arabica)、粗丝多辐藻(M.clavata)和马尾多辐藻(M.sargassi)。     

干旱胁迫对苜蓿脯氨酸累积的影响

用PEG-6000高渗溶液模拟干旱胁迫,研究了干旱胁迫对首蓿累积脯氨酸的影响,实验结果表明,四种苜蓿在不同浓度PEG溶液和一定时间范围内都有游离脯氨酸的累积,而且每种苜蓿在20%PEG溶液中48h游离脯氨酸的量最多,以中牧1号苜蓿累积量最高,累积脯氨酸是苜蓿幼苗对干旱环境的适应性表现。     

Variance reduction by simultaneous multi-exponential analysis of data sets from different experiments

The analysis of experimental data from the photocycle of bacteriorhodopsin (bR) as sums of exponentials has accumulated a large amount of information on its kinetics which is still controversial. One reason for ambiguous results can be found in the inherent instabilities connected with the fitting of noisy data by sums of exponentials. Nevertheless, there are strategies to optimize the experiments and the data analysis by a proper combination of well known techniques. This paper describes an applicable approach based on the correct weighting of the data, a separation of the linear and the non-linear parameters in the process of the least squares approximation, and a statistical analysis applying the correlation matrix, the determinant of Fisher's information matrix, and the variance of the parameters as a measure of the reliability of the results. In addition, the confidence regions for the linear approximation of the non-linear model are compared with confidence regions for the true non-linear model. Evaluation techniques and rules for an optimum experimental design are mainly exemplified by the analysis of numerically generated model data with increasing complexity. The estimation of the number of exponentials significant for the interpretation of a given set of data is demonstrated by using records from eight absorption and photocurrent experiments on the photocycle of bacteriorhodopsin. Offprint requests to: K.-H. Müller     

Regulated genes in mesenchymal stem cells and gastric cancer

AIM: To investigate the genes regulated in mesenchymal stem cells(MSCs) and diffuse-type gastric cancer(GC),gene expression was analyzed. METHODS: Gene expression of MSCs and diffuse-type GC cells were analyzed by microarray. Genes related to stem cells, cancer and the epithelial-mesenchymal transition(EMT) were extracted from human gene lists using Gene Ontology and reference information. Gene panels were generated, and messenger RNA gene expression in MSCs and diffuse-type GC cells was analyzed. Cluster analysis was performed using the NCSS software.RESULTS: The gene expression of regulator of G-protein signaling 1(RGS1) was up-regulated in diffuse-type GC cells compared with MSCs. A panel of stem-cell related genes and genes involved in cancer or the EMT were examined. Stem-cell related genes, such as growth arrest-specific 6, musashi RNA-binding protein 2 and hairy and enhancer of split 1(Drosophila), NOTCH family genes and Notch ligands, such as delta-like 1(Drosophila) and Jagged 2, were regulated.CONCLUSION: Expression of RGS1 is up-regulated, and genes related to stem cells and NOTCH signaling are altered in diffuse-type GC compared with MSCs.     

The Burden and Etiology of Community-Onset Pneumonia in the Aging Japanese Population: A Multicenter Prospective Study

Background

The increasing burden of pneumonia in adults is an emerging health issue in the era of global population aging. This study was conducted to elucidate the burden of community-onset pneumonia (COP) and its etiologic fractions in Japan, the world’s most aged society.

Methods

A multicenter prospective surveillance for COP was conducted from September 2011 to January 2013 in Japan. All pneumonia patients aged ≥15 years, including those with community-acquired pneumonia (CAP) and health care-associated pneumonia (HCAP), were enrolled at four community hospitals on four major islands. The COP burden was estimated based on the surveillance data and national statistics.

Results

A total of 1,772 COP episodes out of 932,080 hospital visits were enrolled during the surveillance. The estimated overall incidence rates of adult COP, hospitalization, and in-hospital death were 16.9 (95% confidence interval, 13.6 to 20.9), 5.3 (4.5 to 6.2), and 0.7 (0.6 to 0.8) per 1,000 person-years (PY), respectively. The incidence rates sharply increased with age; the incidence in people aged ≥85 years was 10-fold higher than that in people aged 15-64 years. The estimated annual number of adult COP cases in the entire Japanese population was 1,880,000, and 69.4% were aged ≥65 years. Aspiration-associated pneumonia (630,000) was the leading etiologic category, followed by Streptococcus pneumoniae-associated pneumonia (530,000), Haemophilus influenzae-associated pneumonia (420,000), and respiratory virus-associated pneumonia (420,000), including influenza-associated pneumonia (30,000).

Conclusions

A substantial portion of the COP burden occurs among elderly members of the Japanese adult population. In addition to the introduction of effective vaccines for S. pneumoniae and influenza, multidimensional approaches are needed to reduce the pneumonia burden in an aging society.