人体小卫星DNA探针的制备

根据人体小卫星DNA核心顺序,化学合成长23碱基寡核苷酸探针,筛选人体基因组文库,旨在获得能用作遗传分析探针的小卫星顺序。结果得到15个含小卫星的阳性重组子。随机取其一(C_(35.9))作探针,试做群体分析。所有个体均可检出多条杂交带。其中某些带具有多态性。在一定检测条件下,检出的DNA图谱在有限的个体内具有个体特异性。结果表明筛选文库得到的小卫星顺序可用于小卫星多态性的检测。其它小卫星探针的筛选和应用性研究正在进行。     

One-Pot Purification and Immobilization of Phenylalanine Dehydrogenase from Bacillus nanhaiensi by Functional Reduced Graphene Oxide

Marine Biotechnology - The one-pot immobilization of halophilic phenylalanine dehydrogenase from marine microorganism with metal ions modified reduced graphene oxide (CRGO) material was studied....     

Health risk assessment of heavy metals in groundwater of coal mining area: A case study in Dingji coal mine,Huainan coalfield,China

Heavy metals enrichment in groundwater poses great ecological risks to human beings. In the present research work, a total of 59 groundwater samples from 12 sampling points in Dingji coal mine, Huainan coalfield, were collected and measured for Cu, Pb, Zn, Cd, Ni, Mn, Cr, and Fe by inductively coupled plasma mass spectrometry (ICP-MS). The human health risk caused by heavy metals through the pathway of drinking water was evaluated and analyzed using the US Environment Protection Agency (USEPA) evaluation model. It has been found that the carcinogenic risk values were between 1.05 × 10^?5 and 3.5 × 10^?4, all exceeding the maximum acceptable level recommended by the USEPA, and the carcinogenic risk of Cr accounted for 99.67% of the total carcinogenic risk. The non-carcinogenic health risk values were all lower than the negligible level given by the USEPA, and the contribution of non-carcinogenic health risk was in the order of Cr > Zn > Cu / Pb >Mn > Fe > Cd > Ni. Among them, Cr had the largest contribution, accounting for 36% of the total non-carcinogenic risk value. In this study, the carcinogenic risk constituted 99.99% of the total health risk, indicating that the total health risk essentially consisted of carcinogenic risk. The research results suggest that much more attention should be paid to the health risk caused by Cr in the groundwater.     

Linking Changes in Epithelial Morphogenesis to Cancer Mutations Using Computational Modeling

Most tumors arise from epithelial tissues, such as mammary glands and lobules, and their initiation is associated with the disruption of a finely defined epithelial architecture. Progression from intraductal to invasive tumors is related to genetic mutations that occur at a subcellular level but manifest themselves as functional and morphological changes at the cellular and tissue scales, respectively. Elevated proliferation and loss of epithelial polarization are the two most noticeable changes in cell phenotypes during this process. As a result, many three-dimensional cultures of tumorigenic clones show highly aberrant morphologies when compared to regular epithelial monolayers enclosing the hollow lumen (acini). In order to shed light on phenotypic changes associated with tumor cells, we applied the bio-mechanical IBCell model of normal epithelial morphogenesis quantitatively matched to data acquired from the non-tumorigenic human mammary cell line, MCF10A. We then used a high-throughput simulation study to reveal how modifications in model parameters influence changes in the simulated architecture. Three parameters have been considered in our study, which define cell sensitivity to proliferative, apoptotic and cell-ECM adhesive cues. By mapping experimental morphologies of four MCF10A-derived cell lines carrying different oncogenic mutations onto the model parameter space, we identified changes in cellular processes potentially underlying structural modifications of these mutants. As a case study, we focused on MCF10A cells expressing an oncogenic mutant HER2-YVMA to quantitatively assess changes in cell doubling time, cell apoptotic rate, and cell sensitivity to ECM accumulation when compared to the parental non-tumorigenic cell line. By mapping in vitro mutant morphologies onto in silico ones we have generated a means of linking the morphological and molecular scales via computational modeling. Thus, IBCell in combination with 3D acini cultures can form a computational/experimental platform for suggesting the relationship between the histopathology of neoplastic lesions and their underlying molecular defects.     

Technetium-99m-labeling and synthesis of thymidine analogs: potential candidates for tumor imaging

The technetium-99m-labeling and synthesis of a series of thymidine analogs were studied. The target molecules were obtained by using 6-hydrazinopyridine-3-carboxylic acid (HYNIC) as a bifunctional coupling agent and using N-(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)glycine (tricine) and ethylenediamine-N,N'-diacetic acid (EDDA) as coligands. The effects of different spacers between thymidine analog with HYNIC on radiochemical yield were also studied.     

桂林岩溶石山常绿落叶阔叶混交林乔木层优势物种生态位研究

采用样方法对不同资源位群落进行调查,通过冗余分析（RDA）结合Monte Carlo随机置换检验筛选出对桂林岩溶石山常绿落叶阔叶混交林乔木层优势物种分布影响显著的土壤资源轴（土壤有机质、土壤水溶钙、土壤速效氮、土壤全氮、土壤pH值和土壤厚度）。利用Levins生态位宽度指数和Pianka生态位重叠指数对桂林岩溶石山常绿落叶阔叶混交林乔木层14个优势物种在土壤有机质、土壤水溶钙、土壤速效氮、土壤全氮、土壤pH值和土壤厚度6个土壤资源轴上的生态位特征进行研究。结果表明：（1）在土壤有机质和土壤水溶钙资源轴上,生态位宽度最大值为常绿物种檵木（0.89、0.94）;在土壤pH值资源轴上,生态位宽度最大值为常绿物种粗糠柴（0.96）;在土壤速效氮、土壤全氮和土壤厚度资源轴上,生态位宽度最大值为落叶物种南酸枣（0.87、0.99、0.97）。（2）14个优势物种在6个土壤资源轴上,生态位重叠均值由大到小依次为土壤厚度 > 土壤全氮 > 土壤水溶钙 > 土壤速效氮 > 土壤pH值 > 土壤有机质,且均表现为常绿物种与常绿物种形成的种对生态位重叠均值（0.84） > 常绿物种与落叶物种（0.74） > 落叶物种与落叶物种（0.66）。（3）综合6个土壤资源轴,生态位重叠值≥0.5的种对高达480对,占总种对数的87.91%,暗示桂林岩溶石山常绿落叶阔叶混交林乔木层优势物种在资源匮乏且资源异质性高的特殊生境中存在激烈竞争,且乔木层种间关系相对不稳定。     

Rmg8 and Rmg7, wheat genes for resistance to the wheat blast fungus,recognize the same avirulence gene AVR‐Rmg8

Rmg8 and Rmg7 are genes for resistance to the wheat blast fungus (Pyricularia oryzae), located on chromosome 2B in hexaploid wheat and chromosome 2A in tetraploid wheat, respectively. AVR‐Rmg8, an avirulence gene corresponding to Rmg8, was isolated from a wheat blast isolate through a map‐based strategy. The cloned fragment encoded a small protein containing a putative signal peptide. AVR‐Rmg8 was recognized not only by Rmg8, but also by Rmg7, suggesting that these two resistance genes are equivalent to a single gene from the viewpoint of resistance breeding.