TNF-α induced altered signaling mechanism in human neutrophil

In the present study we investigated the TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> induced signal transduction mechanism in human neutrophil. Exogenously added TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> affects both PKC activity and its translocation from cytosol to the membrane. Endogenous protein phosphorylation pattern is inhibited in TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> induced neutrophil in Ca-dependent and Ca-independent manner, including a major 47 and 66 kDa cytosolic proteins, which may be implicated in superoxide anion generation. However TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> dose dependently enhances the expression of px169/xxlarge950.gif" alt="zeta" align="MIDDLE" BORDER="0">-PKC isotype but not the px169/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-PKC. Morphology and cell cytotoxicity are studied in TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> treated neutrophil to understand the TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> induced cell death or apoptosis and these experiment is further confirmed by DNA fragmentation analysis. These results clearly demonstrate that TNF-px169/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> induces cellular death of human neutrophil at least in part by enhanced expression of Ca-independent px169/xxlarge950.gif" alt="zeta" align="MIDDLE" BORDER="0">-PKC. These observations provide an insight towards understanding the function of px169/xxlarge950.gif" alt="zeta" align="MIDDLE" BORDER="0">-PKC in apoptotic pathway.     

In silico study of kinetochore control, amplification, and inhibition effects in MCC assembly

Eukaryotic cells rely on a surveillance mechanism, the "Spindle Assembly Checkpoint"SACM in order to ensure accurate chromosome segregation by preventing anaphase initiation until all chromosomes are correctly attached to the mitotic spindle. In different organisms, a mitotic checkpoint complex (MCC) composed of Mad2, Bub3, BubR1/Mad3, and Cdc20 inhibits the anaphase promoting complex (APC/C) to initiate promotion into anaphase. The mechanism of MCC formation and its regulation by the kinetochore are unclear. Here, we constructed dynamical models of MCC formation involving different kinetochore control mechanisms including amplification as well as inhibition effects, and analysed their quantitative properties. In particular, in this system, fast and stable metaphase to anaphase transition can only be triggered when the kinetochore controls the Bub3:BubR1-related reactions; signal amplification and inhibition play a subordinate role. Furthermore, when introducing experimentally determined parameter values into the models analysed here, we found that effective MCC formation is not combined with complete Cdc20 sequestering. Instead, the MCC might bind and completely block the APC/C. The SACM might function by an MCC:APC/C complex rearrangement.     

玉米（Zea mays L.）过氧化物酶编码基因px和冷调控蛋白编码基因cld的物理定位

过氧化物酶是植物抗病过程中的关键酶,也参与植物抗低温胁迫以及一些正常的植物生长发育生理过程。冷调控蛋白是植物抗低、高温的重要蛋白。近年的研究表明植物抗病、某些正常生长发育过程。冷调控蛋白是植物细胞程序性死亡有关。以玉米自效系黄早四为材料,采用生物素标记,利用原位杂效技术绎玉米中过氧化物酶和冷调控蛋白编码基因ｐｘ与ｃｌｄ进行了原位杂效定位,ＤＡＢ和荧光检测得到了一致的结果。在２号和７号染色体长臂同时     

Conversion of N-acetylglucosamine to CMP-N-acetylneuraminic acid in a cell-free system of rat liver

A soluble fraction of rat liver converts glucosamine and N-acetylglucosamine in the presence of ATP and UTP to N-acetylneuraminic acid. This system, when supplemented with CTP, forms CMP-N-acetylneuraminic acid in high yield. Nicotinamide was found to enhance the synthesis of UDP-N-acetylglucosamine and N-acetylneuraminic acid. Kinetic analysis reveals N-acetylglucosamine 6-phosphate, UDP-N-acetylglucosamine, N-acetylmannosamine, N-acetylmannosamine 6-phosphate and N-acetylneuraminic acid 9-phosphate as intermediates. Under certain experimental conditions, however, an epimerisation of N-acetylglucosamine to N-acetylmannosamine was seen.     

Comparative genomic analysis of eutherian Mas-related G protein-coupled receptor genes

The present study made attempts to update comprehensive eutherian Mas-related G protein-coupled receptor gene data sets, using public eutherian genomic sequence data sets and new genomics and molecular evolution tests. Among 254 potential coding sequences, the most comprehensive gene data set of eutherian Mas-related G protein-coupled receptor genes included 119 complete coding sequences that described eight major gene clusters. The present analysis integrated gene annotations, phylogenetic analysis and protein molecular evolution analysis and first explained differential gene expansion patterns of eutherian Mas-related G protein-coupled receptor genes. The updated classification and nomenclature of eutherian Mas-related G protein-coupled receptor genes were proposed as new framework of future experiments.     

A new method for the determination of microbial activity and critical logP in the presence of organic solvents

A new method to determine microbial activity and critical logP of an organism in the presence of organic solvents has been developed which involves direct contact with a solvent, and a measurement of the developing colony size. This technique has been used to estimate the critical logpx55vw04234868/xxlarge8201.gif" alt="thinsp" align="MIDDLE" BORDER="0">P of Alcaligenes xylosoxidans Y234, and, although the critical logpx55vw04234868/xxlarge8201.gif" alt="thinsp" align="MIDDLE" BORDER="0">P for this organism is 3.5, solvents with logpx55vw04234868/xxlarge8201.gif" alt="thinsp" align="MIDDLE" BORDER="0">P values of up to 4.5 can still reduce microbial activity by up to 55% of the uninhibited amount.     

Wood ash treatment affects seasonal N fluctuations in needles of adult<Emphasis Type="Italic"> Picea abies</Emphasis> trees: a <Superscript>15</Superscript>N-tracer study

A ¹⁵N-tracer experiment was carried out in a stand of adult spruce trees [Picea abies (L.) Karst.] located on the Swiss Plateau in order to investigate the effects of wood ash treatment on seasonal nitrogen fluctuations in fine roots and needles. Treatments included irrigation (W), liquid fertilization (LF) and wood ash (A) application. ¹⁵N fluctuation in fine roots and current to 3-year-old needles was studied after one ¹⁵N pulse for 2 consecutive years (1999, 2000). ¹⁵N tracer was rapidly incorporated into the fine roots of adult trees, and px9nky9uw/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">¹⁵N values reached similar levels in all treatments 2 months after the pulse. In the needles, the largest increase in px9nky9uw/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">¹⁵N was observed in those of the current year. Following the initial peak during spring growth, px9nky9uw/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">¹⁵N values in needles of control trees showed an oscillating pattern through the season. This oscillation is attributed to the increased use of internal N sources, as soon as the roots can no longer meet the increased N demand during the sprouting phase. However, W-, LF- and A-treated trees no longer showed the oscillation in px9nky9uw/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0">¹⁵N. Additional water (W and LF) as well as fertilizer (A and LF) may have induced shifts in the microbial flora, thus increasing the unlabelled N release from the soil. The strongest dampening was observed for the A treatment, indicating sufficient N availability from the soil, and making intensive use of the internal N sources unnecessary. Treatment with wood ash thus resulted in a similar fertilizer response to liquid fertilization.