Allosteric interference in oncogenic FLI1 and ERG transactions by mithramycins

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濒危植物永瓣藤叶片功能性状对环境因子的响应

植物叶片功能性状能够响应环境条件的变化，反应了植物对环境的适应策略。当前，针对藤本植物叶片功能性状地理格局及其环境驱动力的研究较少。以国家重点保护植物永瓣藤（Monimopetalum chinense）为研究对象，对其分布区内11个种群的15个叶片功能性状进行测量，并结合气候、土壤因子来解释叶性状变异。比较叶片性状在局域和区域尺度上的种内变异程度，利用多元逐步回归分析环境因子对叶性状的影响。结果表明，在局域尺度上，永瓣藤叶功能性状变异系数介于3.0%-22.5%，其中，叶面积变异程度最大，叶片碳含量变异最小。永瓣藤叶片形状随纬度上升而变得宽且圆。叶片磷含量相对较低，永瓣藤的生长可能受到了磷限制。土壤与气候因子是叶片性状的重要驱动因素，解释了25%-97%的叶片性状变异。在温度和水分充足的情况下，永瓣藤叶片趋向于的慢速生长的保守策略。总体来说，永瓣藤叶片功能性状通过一定的种内变异和性状组合，并与气候、土壤因子相互作用，适应当前的环境条件。     

The influence of biological and environmental factors on metallothionein concentration in the blood

The concentration of metallothionein (MT), a low-molecular-weight protein, is regulated by many factors, primarily metals (zinc, cadmium, copper), cytokines, glucocorticoides and free radicals. These factors are determined by such aspects of human biology as gender, pregnancy and age, as well as by environmental factors including the use of oral contraceptives and cigarette smoking, all which may affect MT levels in the body.The aim of this study was to investigate the influence of these biological and environmental factors on MT concentrations in erythrocyte lysate and in plasma.MT concentrations were determined by a two-step direct enzyme-linked immunosorbent assay. Evaluation of exposure to cigarette smoking was performed by checking cotinine levels in the plasma of subjects.The studies showed higher MT concentrations in both the erythrocyte lysate and plasma of women when compared to men. Furthermore, pregnancy causes an increase of MT concentration in plasma, while oral contraceptives cause an elevated concentration of MT in erythrocyte lysate. Age impacts plasma MT concentrations in men, whereas it does not affect concentrations of MT in erythrocyte lysate.     

Cytokine cross-talk between phagocytic cells and lymphocytes: Relevance for differentiation/activation of phagocytic cells and regulation of adaptive immunity

Cytokines represent one of the most important elements in the communication among different cell types. They play an increasingly better understood role in the communication among hematopoietic cells and in particular in the reciprocal regulation of effector cell types of innate or natural resistance (phagocytic cells and Natural Killer (NK) cells) and those of adaptive immunity (T and B lymphocytes). Lymphocytes produce several cytokines with either stimulatory (e.g., colony stimulatory factor) or suppressive (e.g., tumor necrosis factors and interferons) effects on proliferation of early hematopoietic cells. Many of these cytokines, alone or acting in synergistic combinations, also have a differentiation-inducing ability on immature myeloid cells and act as powerful potentiators of the cellular functions of terminally differentiated phagocytic cells. The communication between lymphocytes and phagocytic cells is not unidirectional, as phagocytic cells produce factors that regulate lymphocyte activation. In addition to their role as antigen presenting cells expressing costimulatory accessory molecules and secreting cytokines (e.g., IL-1, IL-6, TNF), phagocytic cells have been recently shown to produce Natural Killer cell Stimulatory Factor (NKSF/IL-12). IL-12 is a heterodimeric cytokine with important modulatory functions on cytotoxicity of NK and T cells, lymphocyte proliferation, lymphokine production, and development of T helper cell subsets. These communications between phagocytic cells and lymphocytes are further regulated by negative and positive feedback mechanisms that contribute to maintain the homeostasis of the system in physiologic conditions and to govern the changes in this equilibrium needed for the response to infectious or other foreign agents.     

Mediator structure and conformation change

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Interactions of colonisation density and leaf environments on survival of Trioza eugeniae nymphs

1. Female eugenia psyllids Trioza eugeniae oviposit on the margins of expanding young Syzygium paniculatum leaves. The developing nymphs, feeding within pit‐shaped galls on the leaves, cause the leaves to become curled and deformed. The degree of leaf curling was correlated positively with densities of T. eugeniae nymphs. 2. High relative humidity increased persistence of nymphs on leaves at low insect densities, but persistence did not differ between high or low relative humidity conditions when nymphal densities were high and leaves were greatly curled. 3. Direct insolation increased nymphal mortality. Nymphs on the abaxial leaf surface in the direct sun had lower mortality than similarly exposed nymphs on the adaxial leaf surface. 4. Field populations showed high preference for abaxial leaf surfaces and a stronger preference for shaded adaxial surfaces than for exposed adaxial surfaces. 5. Adverse environmental conditions of direct insolation and low relative humidity may be mitigated by leaf curl associated with moderate populations, however competition at high nymphal density supersedes any potential benefit arising from leaf curling and has a negative effect on nymphal survival.