This study investigated the antifungal activity of leaf extracts of Prosopis africana and Anacardium occidentale against Macrophomina phaseolina, the causal agent of root rot of Sesamum indicum L. Phytochemical analys...This study investigated the antifungal activity of leaf extracts of Prosopis africana and Anacardium occidentale against Macrophomina phaseolina, the causal agent of root rot of Sesamum indicum L. Phytochemical analysis of the two plants showed the presence of alkaloids, saponins, tannins, flavonoids and anthraquinones in petroleum ether, ethyl acetate, methanol and water extracts. The effectiveness of the two medicinal plants viz: P. africana and A. occidentale was tested against the causative agent of root rot of Sesamum indicum L. The effect of plant leaf extracts on mycelia growth of the test organism shows that both P. africana and A. anacardium reduced the mycelia growth significantly as compared to the control (plate, 2, 3, 4). The antifungal property of P. africana and A. occidentale makes these plants of potential interest for the control of the fungi Macrophomina phaseolina.展开更多
本文用RNase-gold标记法处理小鼠中期染色体切片,发现染色单体切面内部及周边有大量较均匀分布的RNA。以玉米18 s rRNA的cDNA及水稻5srRNA的DNA为探针,经电镜原位杂交观察到了小鼠18srRNA和5srRNA均在中期染色单体切面内部及边缘有分布...本文用RNase-gold标记法处理小鼠中期染色体切片,发现染色单体切面内部及周边有大量较均匀分布的RNA。以玉米18 s rRNA的cDNA及水稻5srRNA的DNA为探针,经电镜原位杂交观察到了小鼠18srRNA和5srRNA均在中期染色单体切面内部及边缘有分布,从而首次证明小鼠中期染色体RNA除来源于核仁外,还可以来源于核基质中的5srRNA,但这并非仅有的两种来源。展开更多
Supported noble metal nanoparticles （including nanoclusters） are widely used in many industrial catalytic processes. While the finely dispersed nanostructures are highly active, they are usually thermodynamically un...Supported noble metal nanoparticles （including nanoclusters） are widely used in many industrial catalytic processes. While the finely dispersed nanostructures are highly active, they are usually thermodynamically unstable and tend to aggregate or sinter at elevated temperatures. This scenario is particularly true for supported nanogold catalysts because the gold nanostructures are easily sintered at high temperatures, under reaction conditions, or even during storage at ambient temperature. Here, we demonstrate that isolated Au single atoms dispersed on iron oxide nanocrystallites （Aul/FeOx） are much more sintering- resistant than Au nanostructures, and exhibit extremely high reaction stability for CO oxidation in a wide temperature range. Theoretical studies revealed that the positively charged and surface-anchored Aul atoms with high valent states formed significant covalent metal-support interactions （CMSIs）, thus providing the ultra-stability and remarkable catalytic performance. This work may provide insights and a new avenue for fabricating supported Au catalysts with ultra-high stability.展开更多
Photothermal therapy （PTT） using near-infrared （NIR） laser light and gold nanorods （GNRs） shows promise as a novel cancer treatment modality. However, the laser intensity required to destroy tumor cells located ...Photothermal therapy （PTT） using near-infrared （NIR） laser light and gold nanorods （GNRs） shows promise as a novel cancer treatment modality. However, the laser intensity required to destroy tumor cells located beneath the skin is greater than the threshold intensity that causes skin damage; thus, irradiation with laser light damages the skin as well as the tumor. Here, we show that a temperature control system allows metastatic lymph nodes （LNs） to be treated by PTT using NIR laser light and GNRs, without skin damage. A mouse model of LN metastasis was developed by injection of tumor cells, and the tumor-bearing proper axillary LN was treated with NIR laser light after injection of GNRs. The skin temperature was maintained at 45 ~C during irradiation by using a temperature control system. Bioluminescence imaging revealed that tumor progression was less in LNs exposed to NIR laser light and GNRs than in LNs exposed to NIR laser light alone or controls （no irradiation or GNRs）. Furthermore, the skin and LN capsule were macroscopically intact on day 9 after irradiation with NIR laser light, whereas tumor cells within the LN showed apoptosis. A numerical analysis demonstrated that the high-temperature zone and the LN region showing damage were localized to an area up to 3 mm in depth. The proposed novel PTT technique, using NIR laser light and GNRs with controlled surface cooling, could be applied clinically to treat metastatic LNs located within or outside the area accessible for surgical dissection.展开更多
文摘This study investigated the antifungal activity of leaf extracts of Prosopis africana and Anacardium occidentale against Macrophomina phaseolina, the causal agent of root rot of Sesamum indicum L. Phytochemical analysis of the two plants showed the presence of alkaloids, saponins, tannins, flavonoids and anthraquinones in petroleum ether, ethyl acetate, methanol and water extracts. The effectiveness of the two medicinal plants viz: P. africana and A. occidentale was tested against the causative agent of root rot of Sesamum indicum L. The effect of plant leaf extracts on mycelia growth of the test organism shows that both P. africana and A. anacardium reduced the mycelia growth significantly as compared to the control (plate, 2, 3, 4). The antifungal property of P. africana and A. occidentale makes these plants of potential interest for the control of the fungi Macrophomina phaseolina.
文摘本文用RNase-gold标记法处理小鼠中期染色体切片,发现染色单体切面内部及周边有大量较均匀分布的RNA。以玉米18 s rRNA的cDNA及水稻5srRNA的DNA为探针,经电镜原位杂交观察到了小鼠18srRNA和5srRNA均在中期染色单体切面内部及边缘有分布,从而首次证明小鼠中期染色体RNA除来源于核仁外,还可以来源于核基质中的5srRNA,但这并非仅有的两种来源。
文摘Supported noble metal nanoparticles （including nanoclusters） are widely used in many industrial catalytic processes. While the finely dispersed nanostructures are highly active, they are usually thermodynamically unstable and tend to aggregate or sinter at elevated temperatures. This scenario is particularly true for supported nanogold catalysts because the gold nanostructures are easily sintered at high temperatures, under reaction conditions, or even during storage at ambient temperature. Here, we demonstrate that isolated Au single atoms dispersed on iron oxide nanocrystallites （Aul/FeOx） are much more sintering- resistant than Au nanostructures, and exhibit extremely high reaction stability for CO oxidation in a wide temperature range. Theoretical studies revealed that the positively charged and surface-anchored Aul atoms with high valent states formed significant covalent metal-support interactions （CMSIs）, thus providing the ultra-stability and remarkable catalytic performance. This work may provide insights and a new avenue for fabricating supported Au catalysts with ultra-high stability.
文摘Photothermal therapy （PTT） using near-infrared （NIR） laser light and gold nanorods （GNRs） shows promise as a novel cancer treatment modality. However, the laser intensity required to destroy tumor cells located beneath the skin is greater than the threshold intensity that causes skin damage; thus, irradiation with laser light damages the skin as well as the tumor. Here, we show that a temperature control system allows metastatic lymph nodes （LNs） to be treated by PTT using NIR laser light and GNRs, without skin damage. A mouse model of LN metastasis was developed by injection of tumor cells, and the tumor-bearing proper axillary LN was treated with NIR laser light after injection of GNRs. The skin temperature was maintained at 45 ~C during irradiation by using a temperature control system. Bioluminescence imaging revealed that tumor progression was less in LNs exposed to NIR laser light and GNRs than in LNs exposed to NIR laser light alone or controls （no irradiation or GNRs）. Furthermore, the skin and LN capsule were macroscopically intact on day 9 after irradiation with NIR laser light, whereas tumor cells within the LN showed apoptosis. A numerical analysis demonstrated that the high-temperature zone and the LN region showing damage were localized to an area up to 3 mm in depth. The proposed novel PTT technique, using NIR laser light and GNRs with controlled surface cooling, could be applied clinically to treat metastatic LNs located within or outside the area accessible for surgical dissection.
