AIM: Our previous research on the surgical samples of primary liver cancer with CGH showed that the loss of human chromosome 8p had correlation with the metastatic phenotype of liver cancer. In order to seek the funct...AIM: Our previous research on the surgical samples of primary liver cancer with CGH showed that the loss of human chromosome 8p had correlation with the metastatic phenotype of liver cancer. In order to seek the functional evidence that there could be a metastatsis suppressor gene (s) for liver cancer on human chromosome 8, we tried to transfer normal human chromosome 8 into rat liver cancer cell line C5F, which had high metastatic potential to lung.METHODS: Human chromosome 8 randomly marked with neo gene was introduced into C5F cell line by MMCT and positive microcell hybrids were screened by double selections of G418 and HAT. Single cell isolation cloning was applied to clone microcell hybrids. Finally, STS-PCR and WCP-FISH were used to confirm the introduction.RESULTS: Microcell hybrids resistant to HAT and G418 were obtained and 15 clones were obtained by single-cell isolation cloning. STS-PCR and WCP-FISH proved that human chromosome 8 had been successfully introduced into rat liver cancer cell line C5F. STS-PCR detected a random loss in the chromosome introduced and WCP-FISH found a consistent recombination of the introduced human chromosome with the rat chromosome.CONCLUSION: The successful introduction of human chromosome 8 into highly metastatic rat liver cancer cell line builds the basis for seeking functional evidence of a metastasis suppressor gene for liver cancer harboring on human chromosome 8 and its subsequent cloning.展开更多
AIM: To investigate the effect of adeno-associated virusmediated gene transfer of human endostatin on the growth of hepatocellular carcinoma (HCC).METHODS: HCC cell line Hep3B was infected with recombinantadeno-associ...AIM: To investigate the effect of adeno-associated virusmediated gene transfer of human endostatin on the growth of hepatocellular carcinoma (HCC).METHODS: HCC cell line Hep3B was infected with recombinantadeno-associated virus containing human endostatin gene (rAAV2-hEndo). The results of transfection were detected by RT-PCR and SDS-PAGE assay. MTT assay was used to observe the effects of supernatant of transfected cells on ECV304 cell proliferation. An animal model of HCC was established by injecting Hep3B cells subcutaneously into the back of nude mice. Intratumoral injection of rAAV2hEndo, empty virus and phosphate-buffered saline were given sequentially. Serum endostatin was determined byELISA, the inhibitory effect of endostatin on the growth of xenograft was assessed in 3 wk.RESULTS: The results of RT-PCR and SDS-PAGE assay confirmed that rAAV2-hEndo successfully transfected Hep3B cells, and endostatin was secreted from Hep3B cells to medium. The supernatant of transfected cells markedly inhibited the proliferation of ECV304 cells (P<0.01). Intratumoral injection of rAAV2-hEndo (2×1010v.g.) led to a sustained serum endostatin level ofapproximately (86.71±5.19) ng/mL. The tumor volumeand microvessel density were less in rAAV2-hEndo group than in control groups (P<0.01).CONCLUSION: Human endostatin can be stably expressed by adeno-associated virus-mediated gene transfer and effectively inhibit the growth of HCC.展开更多
A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis ...A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis and experiment results show the frequency difference method is a ideal power saving speed regulation method for the dou- ble inverter and motor system.The experiment system is simply structured,convenient to operate and provides a new way of character testing for frequency conversion speed regulation.展开更多
A high-speed and high-resolution optical A/D quantizer is proposed.Its architecture is discussed.Bit circuits are built by using the phase modulators in parallel.Based on the different character of the half-wave volta...A high-speed and high-resolution optical A/D quantizer is proposed.Its architecture is discussed.Bit circuits are built by using the phase modulators in parallel.Based on the different character of the half-wave voltage for every phase modulator and the polarized bias design of incident light,the RF input signal is coled and transmitted in the form of optical digital signal.According to the principle of the architecture,the high-resolution quantizers with 8-bit and 12-bit,et al.are built,which operate at 100 GS/s.Their quantization noise is invariable almost with bit circuits increasing.The simulation result of 4-bit A/D quantizer is also given.展开更多
Skeletal muscle fitness plays vital roles in human health and disease and is determined by developmental as well as physiological inputs. These inputs control and coordinate muscle fiber programs, including capacity f...Skeletal muscle fitness plays vital roles in human health and disease and is determined by developmental as well as physiological inputs. These inputs control and coordinate muscle fiber programs, including capacity for fuel burning, mitochondrial ATP production, and contraction. Recent studies have demonstrated crucial roles for nuclear receptors and their co-activators, and micro RNAs(mi RNAs) in the regulation of skeletal muscle energy metabolism and fiber type determination. In this review, we present recent progress in the study of nuclear receptor signaling and mi RNA networks in muscle fiber type switching. We also discuss the therapeutic potential of nuclear receptors and mi RNAs in disease states that are associated with loss of muscle fitness.展开更多
For the main purpose of manipulating the functions of molecules, researchers have made great achievements on photoresponsive molecules using light as a trigger. Light has become a promising scientific tool due to it b...For the main purpose of manipulating the functions of molecules, researchers have made great achievements on photoresponsive molecules using light as a trigger. Light has become a promising scientific tool due to it being a clean and noninvasive external stimulant. By attachment of photoresponsive moieties to molecules, the biological activities of molecules can be attenuated by light activation. With wide applications of laser in life sciences, it will be possible to achieve high spatiotemporal resolution. In this review, we focus on photoresponsive nucleic acids for photomodulating gene expression with light activation. With incorporation of photoswitchable or photocleavable moieties, biological behaviors of nucleic acids are photoregulated reversibly or irreversibly. Recent development and applications of photoresponsive nucleic acid in vitro and in vivo have shown a very promising future for manipulation of specific functional genes or disease genes. We expect that photoresponsive nucleic acids will be powerful scientific tools for studying biological events as well as gene therapy agents for genetic diseases.展开更多
Two-dimensional,ultrathin,robust,and fullyπ-conjugated organic nanomaterials are highly desirable for application in various fields due to their unique photoelectric characteristics and great number of exposed active...Two-dimensional,ultrathin,robust,and fullyπ-conjugated organic nanomaterials are highly desirable for application in various fields due to their unique photoelectric characteristics and great number of exposed active sites.However,such matters combining excellent stability,fullπ-conjugation and adjustability are rare,which has become a bottleneck for their practical application.Herein,we present a novel kind of diyne-linked polymetalloporphyrin nanosheet featuring permanent porosity and fullπ-conjugation,which exhibits a high-aspect-ratio,outstanding stability and convenient tailoring for electronic structures.Importantly,the novel nanosheets with monodisperse nickel atoms were found to be outstanding heterogeneous catalyst with unprecedented catalytic activity and selectivity for 4-nitrophenol reduction to 4-aminophenol under mild conditions.The findings recommend that diynelinked polymetalloporphyrin nanosheets may offer new platforms for the conversion of photoelectricity and energy in the future.展开更多
基金The State Key Basic Research Program,No.G1998051200National Scientific Foundation of China,No.30271459
文摘AIM: Our previous research on the surgical samples of primary liver cancer with CGH showed that the loss of human chromosome 8p had correlation with the metastatic phenotype of liver cancer. In order to seek the functional evidence that there could be a metastatsis suppressor gene (s) for liver cancer on human chromosome 8, we tried to transfer normal human chromosome 8 into rat liver cancer cell line C5F, which had high metastatic potential to lung.METHODS: Human chromosome 8 randomly marked with neo gene was introduced into C5F cell line by MMCT and positive microcell hybrids were screened by double selections of G418 and HAT. Single cell isolation cloning was applied to clone microcell hybrids. Finally, STS-PCR and WCP-FISH were used to confirm the introduction.RESULTS: Microcell hybrids resistant to HAT and G418 were obtained and 15 clones were obtained by single-cell isolation cloning. STS-PCR and WCP-FISH proved that human chromosome 8 had been successfully introduced into rat liver cancer cell line C5F. STS-PCR detected a random loss in the chromosome introduced and WCP-FISH found a consistent recombination of the introduced human chromosome with the rat chromosome.CONCLUSION: The successful introduction of human chromosome 8 into highly metastatic rat liver cancer cell line builds the basis for seeking functional evidence of a metastasis suppressor gene for liver cancer harboring on human chromosome 8 and its subsequent cloning.
基金Supported by the National Natural Science Foundation of China, No. 20074031
文摘AIM: To investigate the effect of adeno-associated virusmediated gene transfer of human endostatin on the growth of hepatocellular carcinoma (HCC).METHODS: HCC cell line Hep3B was infected with recombinantadeno-associated virus containing human endostatin gene (rAAV2-hEndo). The results of transfection were detected by RT-PCR and SDS-PAGE assay. MTT assay was used to observe the effects of supernatant of transfected cells on ECV304 cell proliferation. An animal model of HCC was established by injecting Hep3B cells subcutaneously into the back of nude mice. Intratumoral injection of rAAV2hEndo, empty virus and phosphate-buffered saline were given sequentially. Serum endostatin was determined byELISA, the inhibitory effect of endostatin on the growth of xenograft was assessed in 3 wk.RESULTS: The results of RT-PCR and SDS-PAGE assay confirmed that rAAV2-hEndo successfully transfected Hep3B cells, and endostatin was secreted from Hep3B cells to medium. The supernatant of transfected cells markedly inhibited the proliferation of ECV304 cells (P<0.01). Intratumoral injection of rAAV2-hEndo (2×1010v.g.) led to a sustained serum endostatin level ofapproximately (86.71±5.19) ng/mL. The tumor volumeand microvessel density were less in rAAV2-hEndo group than in control groups (P<0.01).CONCLUSION: Human endostatin can be stably expressed by adeno-associated virus-mediated gene transfer and effectively inhibit the growth of HCC.
文摘A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis and experiment results show the frequency difference method is a ideal power saving speed regulation method for the dou- ble inverter and motor system.The experiment system is simply structured,convenient to operate and provides a new way of character testing for frequency conversion speed regulation.
基金Natural Science Foundation from Colleges and Universities of Jiangsu Province(04KJD140033)
文摘A high-speed and high-resolution optical A/D quantizer is proposed.Its architecture is discussed.Bit circuits are built by using the phase modulators in parallel.Based on the different character of the half-wave voltage for every phase modulator and the polarized bias design of incident light,the RF input signal is coled and transmitted in the form of optical digital signal.According to the principle of the architecture,the high-resolution quantizers with 8-bit and 12-bit,et al.are built,which operate at 100 GS/s.Their quantization noise is invariable almost with bit circuits increasing.The simulation result of 4-bit A/D quantizer is also given.
基金supported by the Model Animal Research Center of Nanjing University Start Fundthe Jiangsu Natural Science Foundation(BK20140600)
文摘Skeletal muscle fitness plays vital roles in human health and disease and is determined by developmental as well as physiological inputs. These inputs control and coordinate muscle fiber programs, including capacity for fuel burning, mitochondrial ATP production, and contraction. Recent studies have demonstrated crucial roles for nuclear receptors and their co-activators, and micro RNAs(mi RNAs) in the regulation of skeletal muscle energy metabolism and fiber type determination. In this review, we present recent progress in the study of nuclear receptor signaling and mi RNA networks in muscle fiber type switching. We also discuss the therapeutic potential of nuclear receptors and mi RNAs in disease states that are associated with loss of muscle fitness.
基金State Key Laboratory of Natural and Biomimetic Drugs and Peking University(bmu2009137-121)
文摘For the main purpose of manipulating the functions of molecules, researchers have made great achievements on photoresponsive molecules using light as a trigger. Light has become a promising scientific tool due to it being a clean and noninvasive external stimulant. By attachment of photoresponsive moieties to molecules, the biological activities of molecules can be attenuated by light activation. With wide applications of laser in life sciences, it will be possible to achieve high spatiotemporal resolution. In this review, we focus on photoresponsive nucleic acids for photomodulating gene expression with light activation. With incorporation of photoswitchable or photocleavable moieties, biological behaviors of nucleic acids are photoregulated reversibly or irreversibly. Recent development and applications of photoresponsive nucleic acid in vitro and in vivo have shown a very promising future for manipulation of specific functional genes or disease genes. We expect that photoresponsive nucleic acids will be powerful scientific tools for studying biological events as well as gene therapy agents for genetic diseases.
基金the National Natural Science Foundation of China(21774040,61435005,and 21805110)。
文摘Two-dimensional,ultrathin,robust,and fullyπ-conjugated organic nanomaterials are highly desirable for application in various fields due to their unique photoelectric characteristics and great number of exposed active sites.However,such matters combining excellent stability,fullπ-conjugation and adjustability are rare,which has become a bottleneck for their practical application.Herein,we present a novel kind of diyne-linked polymetalloporphyrin nanosheet featuring permanent porosity and fullπ-conjugation,which exhibits a high-aspect-ratio,outstanding stability and convenient tailoring for electronic structures.Importantly,the novel nanosheets with monodisperse nickel atoms were found to be outstanding heterogeneous catalyst with unprecedented catalytic activity and selectivity for 4-nitrophenol reduction to 4-aminophenol under mild conditions.The findings recommend that diynelinked polymetalloporphyrin nanosheets may offer new platforms for the conversion of photoelectricity and energy in the future.