Distribution pattern of an expanding Osprey ( Pandion haliaetus) population in a changing environment

We studied the nest site selection and distribution pattern at landscape level of the German Osprey population, and demonstrated how to test the predictions of the ideal free distribution theory and its derivatives on such an expanding population. Information about the location and breeding success of each Osprey nest site between 1995 and 2005 was collected through a long-term monitoring programme. Data of land cover types were acquired from the administrations of each federal state and the CORINE Land Cover database. The results showed that Ospreys preferred landscapes with more water bodies and forests. Such sites were also occupied earlier and had higher local population density. However, in the study period of 11 years, there was a gradual shift from forest-dominated landscapes to agricultural land-dominated landscapes. The breeding success increased over time, with no difference in the breeding success between pairs nesting on trees and poles, whereas there was higher breeding success at nest sites surrounded by more agricultural land and less forest. The more efficient foraging in eutrophic lakes in agricultural landscapes was the most likely cause for the higher breeding success. The distribution pattern of the Ospreys did not match the resource allocation, which deviated from the models tested. We suggested that the proximate cues used for nest site selection mismatched site quality due to anthropogenic environmental changes.     

Synthesis and bioevaluation of ω-N-amino analogs of B13

Novel ω-N-amino analogs of B13 (Class E) were designed, synthesized and tested as inhibitors of acid ceramidase (ACDase) and potential anticancer agents deprived of unwanted lysosomal destabilization and ACDase proteolytic degradation properties of LCL204 [Szulc, Z. M.; Mayroo, N.; Bai, A.; Bielawski, J.; Liu, X.; Norris, J. S.; Hannun, Y. A.; Bielawska, A. Bioorg. Med. Chem. 2008, 16, 1015].Representative analog LCL464, (1R,2R)-2-N-(12′-N,N-dimethylaminododecanoyl amino)-1-(4″-nitrophenyl)-1,3-propandiol, inhibited ACDase activity in vitro, with a similar potency as B13 but higher than LCL204. LCL464 caused an early inhibition of this enzyme at a cellular level corresponding to decrease of sphingosine and specific increase of C₁₄- and C₁₆-ceramide. LCL464 did not induce lysosomal destabilization nor degradation of ACDase, showed increased cell death demonstrating inherent anticancer activity in a wide range of different cancer cell lines, and induction of apoptosis via executioner caspases activation. LCL464 represents a novel structural lead as chemotherapeutic agent acting via the inhibition of ACDase.     

自絮凝酵母高浓度重复批次乙醇发酵

利用发酵性能优良的自絮凝酵母Saccharomyces cerevisiaeflo,研究开发了重复批次高浓度乙醇发酵系统,以节省下游加工过程的能耗。在终点乙醇浓度达到120g/L左右的条件下,发酵系统的乙醇生产强度达到8.2g/(L·h)。然而实验中发现,随着发酵批次的增多,自絮凝酵母沉降性能逐渐下降,从发酵液中沉降分离所需时间相应延长,导致发酵液中高浓度乙醇对酵母的毒害作用加剧,影响其发酵活性和发酵系统运行的稳定性,发酵装置运行11个批次后无法继续运行。实验结果表明,絮凝能力下降导致的酵母絮凝颗粒尺度减小是其沉降性能下降的主要原因。进一步研究发现,酵母的絮凝能力通过再培养可以恢复。在此基础上对发酵系统操作进行改进,每批发酵结束后可控采出一定比例菌体,调节系统的酵母细胞密度和乙醇生产强度以刺激酵母增殖,保持其絮凝能力。在达到相同发酵终点乙醇浓度条件下,虽然发酵系统的乙醇生产强度降低到4.0g/(L·h),但运行10d后絮凝颗粒酵母尺度趋于稳定,继续运行14d,未发现絮凝颗粒酵母尺度继续下降的现象,系统可以稳定运行。     

细胞色素P450调节肝脏药物代谢的途径

大量研究认为细胞色素P450与药物性肝损伤的病理生理过程密切相关,对其在肝损伤的作用已成为当前研究的一个热点.主要介绍细胞色素P450与药物性肝损伤的相关研究进展.     

基于23S／5SrDNA序列的柑橘黄龙病病原菌亚洲种系统发育研究

根据柑橘黄龙病亚洲种23S/5S的DNA序列设计一对引物对不同地理来源的6个柑橘黄龙病样品DNA进行扩增,扩增片段大小均为1 654 bp包括一个假定细胞壁水解酶假基因(putative cell wall hydrolase pseudogene)和5S rRNA 基因.序列同源性分析结果表明;6个柑橘黄龙病病原菌样品与柑橘黄龙病病原菌亚洲种Sihui样品的同源性为99%,然而与土壤杆菌,布鲁氏菌,根瘤菌,中华根瘤菌,巴通体菌和中慢生根瘤菌的同源性只有89%～95%,说明在23S/5S rDNA序列上黄龙病病原菌亚洲种与α变形菌纲根瘤菌目的其他病原菌相差较大.对黄龙病病原菌亚洲种种内的23S/5S rDNA序列进行比较分析,结果发现黄龙病病原菌亚洲种种内之间putative cell wall hydrolase pseudogene和5S rRNA的基因序列非常保守,但不同地理来源的柑橘黄龙病样品碱基序列间确实存在差异,差异的大小与地理的远近无关.利用简约法对黄龙病病原菌亚洲种及α变形菌纲其它病原菌的23S/5S rDNA序列构建的系统发育树显示黄龙病病原菌亚洲种单独聚为一类,其他细菌聚为另一类,该结果与基于rplJ基因及16S rRNA基因的DNA序列构建的分子系统进化树结果一致.     

Establishment and characterization of a fibroblast cell line from the Mongolian horse

A fibroblast line was successfully established from Mongolian horse ear marginal tissue by using a primary explant technique and cell cryogenic preservation technology. Biological analysis showed the following: The cells were adherent and exhibited density-dependent inhibition of proliferation; assays of microbial contamination from bacteria, fungi, and mycoplasma were negative; the population doubling time of the cells was 33.9 h; and a 2n chromosome number of 64 at a frequency higher than 80%. A lack of cross-contamination of this cell line with other species was confirmed by isoenzyme analysis of lactic and malic dehydrogenases. In order to study exogenous gene expression, four fluorescent proteins, pEGFP-N3, pEGFP-C1, pDsRed1-N1, and pEYFP-N1, were transfected into the cells. The corresponding fluorescence was distributed throughout the cytoplasm and nucleus 12 h after transfection. This cell line not only preserves the genetic resources of the Mongolian horse at the cellular level but also provides valuable materials for genomic, postgenomic, and somacloning research in this species.     

The level of Hsp27 in lymphocytes is negatively associated with a higher risk of lung cancer

Heat shock proteins (Hsps) can protect cells, organs, and whole organisms against damage caused by abnormal environmental hazards. Some studies have reported that lymphocyte Hsps may serve as biomarkers for evaluating disease status and exposure to environmental stresses; however, few epidemiologic studies have examined the associations between lymphocyte Hsps levels and lung cancer risk. We examined lymphocyte levels of Hsp27 and Hsp70 in 263 lung cancer cases and age- and gender-matched cancer-free controls by flow cytometry. Multivariate logistic regression models were used to estimate the association between lymphocyte Hsps levels and lung cancer risk. Our results showed that Hsp27 levels were significantly lower in lung cancer cases than in controls (16.5 vs 17.8 mean fluorescence intensity, P < 0.001). This was not observed for Hsp70 levels. Further stratification analysis revealed that lymphocyte Hsp27 levels were negatively associated with lung cancer risk especially in males and heavy smokers. There was a statistical trend of low odd ratios (95% confidence intervals) and upper tertile levels of Hsp27 [1.000, 0.904 (0.566–1.444) and 0.382 (0.221–0.658, P _trend = 0.001) in males and 1.000, 0.9207 (0.465–1.822) and 0.419 (0.195–0.897, P _trend = 0.036) in heavy smokers] after adjustment for confounding factors. These results suggest that lower lymphocyte Hsp27 levels might be associated with an increased risk of lung cancer. Our findings need to be validated in a large prospective study. Feng Wang and Maohui Feng contributed equally to this work.     

Taxonomy of the Streptomyces strain ZG0656 that produces acarviostatin α-amylase inhibitors and analysis of their effects on blood glucose levels in mammalian systems

Aims:  To clarify the taxonomic status of strain ZG0656 and analyse the effects of its acarviostatin products on blood glucose levels in mammalian systems.
Methods and Results:  Our program to screen for new α-amylase inhibitors led to the isolation of strain ZG0656. The polyphasic taxonomic study revealed that strain ZG0656 represents a novel variation of Streptomyces coelicoflavus , for which we propose the name S. coelicoflavus var. nankaiensis . Four chemically distinct α-amylase inhibitors, acarviostatins I03, II03, III03 and IV03, were isolated from strain ZG0656. Acarviostatins III03 and IV03 are both novel oligomers. All four acarviostatins are mixed noncompetitive porcine pancreas α-amylase inhibitors. Acarviostatin III03 is the most potent α-amylase inhibitor known to date. Moreover, in the in vitro and in vivo experiments, acarviostatins III03 showed significant inhibition of starch hydrolysis and glucose transfer to blood.
Conclusions:  Strain ZG0656 is a novel variation of S. coelicoflavus, whose products are novel effective α-amylase inhibitors. Among the products, acarviostatins III03 could significantly depress blood glucose levels in mammalian systems and be developed towards a possible therapeutic agent for diabetes.
Significance and Impact of the Study:  Acarviostatin III03 is the most potent α-amylase inhibitor known to date. The oligomer will benefit the research on the relationship between α-amylase and various inhibitors and will offer more choices in diabetes treatments.