A major portion of the beneficial effect of mesenchymal stem cells (MSC) is due to the production of trophic and angiogenic factors by these cells, and one of the efforts to improve the therapeutic efficacy of these c...A major portion of the beneficial effect of mesenchymal stem cells (MSC) is due to the production of trophic and angiogenic factors by these cells, and one of the efforts to improve the therapeutic efficacy of these cells lies in enhancing this capacity. Since there is complement activation in all areas of tissue injury, and both C3a and C5a activate MSC, it was asked whether stimulation with C3a or C5a would upregulate the production of trophic factors by MSC. C3a caused significant up-regulation of various angiogenic factors, including VEGF, CXCL8/IL-8 and IL-6. In contrast there was no detectable production of the pro-inflammatory cytokines TNF-α and IL-1β in spite of nuclear translocation of NFκB. Although C5a also caused moderate up-regulation of angiogenic factors, the effect was borderline significant. Furthermore the production of angiogenic factors induced by C3a was of physiological relevance: Supernatants of MSCs cultured under serum-free conditions induced minimal tube formation of HUVECs as an in vitro measure of angiogenesis;tube formation was considerably enhanced, when supernatants from C3a-stimulated MSC were used, while C3a itself had no direct angiogenic effect on HUVECs. The signaling cascade responsible for the production of angiogenic factors by C3a or C5a could be defined as activation of the rho cascade which was necessary for nuclear translocation of NFκB p65 and of phospho-ERK1/2. Although rho was only transiently activated, inhibition of the rho or “downstream of it” of the NFκB pathway, prevented C3a-and C5a-induced up-regulation of angiogenic factors.展开更多
Phytohormone abscisic acid (ABA) was critical for many plant growth and developmental processesincluding seed maturation, germination and response to environmental factors. With the purpose to detectthe possible ABA r...Phytohormone abscisic acid (ABA) was critical for many plant growth and developmental processesincluding seed maturation, germination and response to environmental factors. With the purpose to detectthe possible ABA related signal transduction pathways, we tried to isolate ABA-regulated genes throughcDNA macroarray technology using ABA-treated rice seedling as materials (under treatment for 2, 4, 8 and12 h). Of 6144 cDNA clones tested, 37 differential clones showing induction or suppression for at least onetime, were isolated. Of them 30 and 7 were up- or down-regulated respectively. Sequence analyses revealedthat the putative encoded proteins were involved in different possible processes, including transcription,metabolism and resistance, photosynthesis, signal transduction, and seed maturation. 6 cDNA clones werefound to encode proteins with unknown functions. Regulation by ABA of 7 selected clones relating to signaltransduction or metabolism was confirmed by reverse transcription PCR. In addition, some clones werefurther shown to be regulated by other plant growth regulators including auxin and brassinosteroid, which,however, indicated the complicated interactions of plant hormones. Possible signal transduction pathwaysinvolved in ABA were discussed.展开更多
Chou and Chen’s report in the 1970s suggested conformational protein adaptation (CPA) might be influenced by low frequency phonons acting as “a possible information system”. This report proposes the universal force...Chou and Chen’s report in the 1970s suggested conformational protein adaptation (CPA) might be influenced by low frequency phonons acting as “a possible information system”. This report proposes the universal force of electromagnetism initiates the phonon system they cited as it per-turbs paramagnetic/diamagnetic dampers within the protein matrix to produce a quantized low frequency phonon signal series. (http://www.phy.ilstu.edu/~ren/phononsims/page3.html) The signal series is iteratively processed by the protein beta sub-unit, the system, to posi-tion the alpha sub-unit, the outcome, a classic non-linear resonance system resulting in con-formational protein adaptation (CPA). CPA “priming” enables a secondary ATP/redox driven power system to complete cell activity. The evolutionary appearance of these two systems reflects their hierarchy: 1) a low energy phonon driven information control circuit governed by principles of physics that, along with proteins, may have preceded planet earth, and 2), an ATP/redox power completion circuit directed by principles of chemistry that evolved in living systems 1 billion or more years after earth formed.展开更多
目的:探讨CXCR4／CXCL12在结直肠癌肝转移中的作用．方法:应用Western blot检测160例结直肠癌患者标本中肿瘤组织、邻近正常黏膜以及肝转移组织中CXCR4／CXCL12通路成员的表达情况,免疫组织化学法检测CXCR4／CXCL12在细胞水平的分布．结...目的:探讨CXCR4／CXCL12在结直肠癌肝转移中的作用．方法:应用Western blot检测160例结直肠癌患者标本中肿瘤组织、邻近正常黏膜以及肝转移组织中CXCR4／CXCL12通路成员的表达情况,免疫组织化学法检测CXCR4／CXCL12在细胞水平的分布．结果:与正常组织相比,结直肠癌组织中 CXCR4／CXCL12表达水平明显增高(P<0．05); 与原发肿瘤相比,10例肝转移组织中CXCR4／ CXCL12表达增高(CXCR4:3．9±0．5 vs 2．2± 0．3,P<0．05:CXCL12:3．6±0．5 vs 2．4±0．3, P<0．05):TNMⅢ、Ⅳ分期CXCR4／CXCL12表达水平比Ⅰ、Ⅱ分期显著增加有关(CXCR4: 3．4±0．6 vs 1．8±0．3．P<0．05;CXCL12:3．6± 0．5 vs 1．8±0．4．P<0．05)．结论:趋化因子受体CXCR4／CXCL12在原发结直肠癌与肝转移组织中呈高表达,CXCR4／ CXCL12信号转导通路可能在结直肠癌肝转移过程中起一定作用．展开更多
文摘A major portion of the beneficial effect of mesenchymal stem cells (MSC) is due to the production of trophic and angiogenic factors by these cells, and one of the efforts to improve the therapeutic efficacy of these cells lies in enhancing this capacity. Since there is complement activation in all areas of tissue injury, and both C3a and C5a activate MSC, it was asked whether stimulation with C3a or C5a would upregulate the production of trophic factors by MSC. C3a caused significant up-regulation of various angiogenic factors, including VEGF, CXCL8/IL-8 and IL-6. In contrast there was no detectable production of the pro-inflammatory cytokines TNF-α and IL-1β in spite of nuclear translocation of NFκB. Although C5a also caused moderate up-regulation of angiogenic factors, the effect was borderline significant. Furthermore the production of angiogenic factors induced by C3a was of physiological relevance: Supernatants of MSCs cultured under serum-free conditions induced minimal tube formation of HUVECs as an in vitro measure of angiogenesis;tube formation was considerably enhanced, when supernatants from C3a-stimulated MSC were used, while C3a itself had no direct angiogenic effect on HUVECs. The signaling cascade responsible for the production of angiogenic factors by C3a or C5a could be defined as activation of the rho cascade which was necessary for nuclear translocation of NFκB p65 and of phospho-ERK1/2. Although rho was only transiently activated, inhibition of the rho or “downstream of it” of the NFκB pathway, prevented C3a-and C5a-induced up-regulation of angiogenic factors.
基金Researches were supported by "the State Key Project of Basic Research, G1999011604" "Key Project of Knowledge Innovation, CAS", "the National Natural Science Foundation of China, No.30070073" "National Sciences Foundation of Pan-Deng". We thank Prof.
文摘Phytohormone abscisic acid (ABA) was critical for many plant growth and developmental processesincluding seed maturation, germination and response to environmental factors. With the purpose to detectthe possible ABA related signal transduction pathways, we tried to isolate ABA-regulated genes throughcDNA macroarray technology using ABA-treated rice seedling as materials (under treatment for 2, 4, 8 and12 h). Of 6144 cDNA clones tested, 37 differential clones showing induction or suppression for at least onetime, were isolated. Of them 30 and 7 were up- or down-regulated respectively. Sequence analyses revealedthat the putative encoded proteins were involved in different possible processes, including transcription,metabolism and resistance, photosynthesis, signal transduction, and seed maturation. 6 cDNA clones werefound to encode proteins with unknown functions. Regulation by ABA of 7 selected clones relating to signaltransduction or metabolism was confirmed by reverse transcription PCR. In addition, some clones werefurther shown to be regulated by other plant growth regulators including auxin and brassinosteroid, which,however, indicated the complicated interactions of plant hormones. Possible signal transduction pathwaysinvolved in ABA were discussed.
文摘Chou and Chen’s report in the 1970s suggested conformational protein adaptation (CPA) might be influenced by low frequency phonons acting as “a possible information system”. This report proposes the universal force of electromagnetism initiates the phonon system they cited as it per-turbs paramagnetic/diamagnetic dampers within the protein matrix to produce a quantized low frequency phonon signal series. (http://www.phy.ilstu.edu/~ren/phononsims/page3.html) The signal series is iteratively processed by the protein beta sub-unit, the system, to posi-tion the alpha sub-unit, the outcome, a classic non-linear resonance system resulting in con-formational protein adaptation (CPA). CPA “priming” enables a secondary ATP/redox driven power system to complete cell activity. The evolutionary appearance of these two systems reflects their hierarchy: 1) a low energy phonon driven information control circuit governed by principles of physics that, along with proteins, may have preceded planet earth, and 2), an ATP/redox power completion circuit directed by principles of chemistry that evolved in living systems 1 billion or more years after earth formed.
文摘针对传统奈奎斯特采样会产生庞大的数据量以及现有的阵列压缩采样系统存在结构复杂、重构运算量大等问题,本文提出了一种基于均匀线型阵列的改进型调制宽带转换器(Modulated Wideband Converter,MWC)的阵列接收系统,无需重构即可直接对接收信号的压缩采样数据进行载频与波达方向(Direction Of Arrival,DOA)估计.所提系统在MWC测频支路中采用周期性循环移位伪随机序列作为混频函数以求得子带索引估计,采用基于快速傅里叶变换(Fast Fourier Transform,FFT)谱线插值法进行基带频率估计,且将MWC测向分支中混频函数设置为相同的伪随机序列,便可直接利用高分辨率的多重信号分类(MUltiple SIgnal Classification,MUSIC)算法对组合压缩采样数据完成DOA估计.实验仿真结果证明了所提系统能较好地从压缩采样数据中完成对目标的载频与DOA参数估计.
文摘目的:探讨CXCR4／CXCL12在结直肠癌肝转移中的作用．方法:应用Western blot检测160例结直肠癌患者标本中肿瘤组织、邻近正常黏膜以及肝转移组织中CXCR4／CXCL12通路成员的表达情况,免疫组织化学法检测CXCR4／CXCL12在细胞水平的分布．结果:与正常组织相比,结直肠癌组织中 CXCR4／CXCL12表达水平明显增高(P<0．05); 与原发肿瘤相比,10例肝转移组织中CXCR4／ CXCL12表达增高(CXCR4:3．9±0．5 vs 2．2± 0．3,P<0．05:CXCL12:3．6±0．5 vs 2．4±0．3, P<0．05):TNMⅢ、Ⅳ分期CXCR4／CXCL12表达水平比Ⅰ、Ⅱ分期显著增加有关(CXCR4: 3．4±0．6 vs 1．8±0．3．P<0．05;CXCL12:3．6± 0．5 vs 1．8±0．4．P<0．05)．结论:趋化因子受体CXCR4／CXCL12在原发结直肠癌与肝转移组织中呈高表达,CXCR4／ CXCL12信号转导通路可能在结直肠癌肝转移过程中起一定作用．
