[Objective] In this study, the quantitive detection of PCV2 （porcine circovirus type 2） in vitro was achieved. We aimed to establish two kinds of TaqMan real-time PCR methods based on PCV20RF1 and ORF2 respectively ...[Objective] In this study, the quantitive detection of PCV2 （porcine circovirus type 2） in vitro was achieved. We aimed to establish two kinds of TaqMan real-time PCR methods based on PCV20RF1 and ORF2 respectively and compare them. [Method] According to the relatively＇conserved sequences of PCV20RF1 and ORF2 registered in GenBank, two pairs of specific primers and TaqMan probes were designed and synthesized. Then the recombinant plasmids containing the whole sequences of PCV20RF1 and ORF2 were constructed to draw the standard curves through optimizing the reaction system and conditions. And thus two kinds of TaqMan real-time PCR detection methods based on the whole sequences of ORF1 and ORF2 respectively were constructed for PCV2. [Result] For the two established standard curves, the Ct values showed a good linear relationship with the loga- rithms of copy numbers of templates （F2〉0.99）. The amplification efficiency ranged from 90% to 110%. The amplifications all had a good repeatability with variation coefficients within groups all less than 5%. Moreover, the amplifications all had a good specificity. When the sequences of porcine parvovirus （PPV）, porcine circovirus type 1 （PCV1）, swine pseudorabies virus （PRV）, porcine reproductive and respiratory syndrome virus （PRRSV） were used as templates, the target sequence was not amplified. The amplifications also had a high sensitivity. The ORF1 detection method could reach 1.0x10T copies/;ul, and the ORF2 detection method could reach 1.0×10^2 copies/μl. The two established real-time PCR detection methods were used to detect the 80 clinical samples respectively. The results showed the magnitudes of 72 amplified samples were basically consistent between the 2 detection methods, while the magnitudes of the other 8 amplified samples were inconsistent. Then the 8 samples were detected with SYBR Green I real-time PCR method established based on the sequence of PCV2-1ike factor P1 by Wen et aL The PCV2-1ike factor P1 was amplified in all the 8 samples, indicating the 8 samples were all infected with PCV2-1ike factor P1. [Conclusion] The ORFl-based detection method has a higher accuracy, and it can be used for the rapid detection of PCV2.展开更多
The family of mammalian chitinases includes members both with and without glycohydrolase enzymatic activity against chitin, a polymer of N-acetylglucosamine. Chitin is the structural component of fungi, crustaceans, i...The family of mammalian chitinases includes members both with and without glycohydrolase enzymatic activity against chitin, a polymer of N-acetylglucosamine. Chitin is the structural component of fungi, crustaceans, insects and parasitic nematodes, but is completely absent in mammals. Exposure to antigens containing chitin- or chitin-like structures sometimes induces strong T helper type-I responses in mammals, which may be associated with the induction of mammalian chitinases. Chitinase 3-like-1 （CHI3L1）, a member of the mammalian chitinase family, is induced specifically during the course of inflammation in such disorders as inflammatory bowel disease, hepatitis and asthma. In addition, CHI3L1 is expressed and secreted by several types of solid tumors including glioblastoma, colon cancer, breast cancer and malignant melanoma. Although the exact function of CHI3L1 in inflammation and cancer is still largely unknown, CHI3L1 plays a pivotal role in exacerbating the inflammatory processes and in promoting angiogenesis and remodeling of the extracellular matrix. CHI3L1 may be highly involved in the chronic engagement of inflammation which potentiates development of epithelial tumorigenesis presumably by activating the mitogen-activated protein kinase and the protein kinase B signaling pathways. Anti-CHI3L1 antibodies or pan-chitinase inhibitors may have the potential to suppress CHI3Ll-mediated chronic inflammation and the subsequent carcinogenic change in epithelial cells.展开更多
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 （1c2, three all...As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 （1c2, three alleles） mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.展开更多
Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well kn...Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well known. In this study, we conducted experiments on the responses of two toxic Microcystis aeruginosa strains （FACHB-905 and FACHB-915） and their microcystin release in conditions of low temperature （15℃ or 4℃, with illumination） or darkness, and subsequent recovery in standard conditions （25℃ with illumination）. On exposure to 15℃, a small decrease in cell viability was observed, but the cell number increased gradually, suggesting that M. aeruginosa FACHB-905 and FACHB-915 cells seem in general tolerant in 15℃. Interestingly, our results show that a higher carotenoid content and microcystin release potentially enhance the fitness of surviving cells at 15℃. M. aeruginosa cells exposed to lower temperature light stress （4℃） did not completely lose viability and retained the ability to reinitiate growth. In darkness, the maximum quantum yield （Fv/Fm） and the maximum electron transport rate （ETRmax） values and cell viability of M. aeruginosa cells gradually decreased with time. During the recovery period, the photosynthetic efficiency of M. aeruginosa reverted to the normal level. Additionally, M. aeruginosa FACHB-905 and FACHB-915 exposed to low temperature had increased caspase-3-1ike activity and DNA fragmentation, which suggests the occurrence of a type of cell death in M. aeruginosa cells under cold stress similar to programmed cell death. Overall, our findings could confer certain advantages on the Microcystis for surviving cold or dark conditions encountered in the annual cycle, and help explain its repeated occurrence in water blooms in large and shallow lakes.展开更多
基金Supported by National Natural Science Foundation of China(31302071)Special Fund for Agro-scientific Research in the Public Interest(201303046)+1 种基金Jiangsu Agricultural Science and Technology Innovation Fund(CX(14)2045)"333 High-level Personnel Training Project"of Jiangsu Province(BRA2012194)~~
文摘[Objective] In this study, the quantitive detection of PCV2 （porcine circovirus type 2） in vitro was achieved. We aimed to establish two kinds of TaqMan real-time PCR methods based on PCV20RF1 and ORF2 respectively and compare them. [Method] According to the relatively＇conserved sequences of PCV20RF1 and ORF2 registered in GenBank, two pairs of specific primers and TaqMan probes were designed and synthesized. Then the recombinant plasmids containing the whole sequences of PCV20RF1 and ORF2 were constructed to draw the standard curves through optimizing the reaction system and conditions. And thus two kinds of TaqMan real-time PCR detection methods based on the whole sequences of ORF1 and ORF2 respectively were constructed for PCV2. [Result] For the two established standard curves, the Ct values showed a good linear relationship with the loga- rithms of copy numbers of templates （F2〉0.99）. The amplification efficiency ranged from 90% to 110%. The amplifications all had a good repeatability with variation coefficients within groups all less than 5%. Moreover, the amplifications all had a good specificity. When the sequences of porcine parvovirus （PPV）, porcine circovirus type 1 （PCV1）, swine pseudorabies virus （PRV）, porcine reproductive and respiratory syndrome virus （PRRSV） were used as templates, the target sequence was not amplified. The amplifications also had a high sensitivity. The ORF1 detection method could reach 1.0x10T copies/;ul, and the ORF2 detection method could reach 1.0×10^2 copies/μl. The two established real-time PCR detection methods were used to detect the 80 clinical samples respectively. The results showed the magnitudes of 72 amplified samples were basically consistent between the 2 detection methods, while the magnitudes of the other 8 amplified samples were inconsistent. Then the 8 samples were detected with SYBR Green I real-time PCR method established based on the sequence of PCV2-1ike factor P1 by Wen et aL The PCV2-1ike factor P1 was amplified in all the 8 samples, indicating the 8 samples were all infected with PCV2-1ike factor P1. [Conclusion] The ORFl-based detection method has a higher accuracy, and it can be used for the rapid detection of PCV2.
基金Supported by NIH (DK64289,DK74454,DK43351 and DK80070)grants from the Eli and Edythe L.Broad Medical FoundationAmerican Gastroenterological Association Foundation for Digestive Health and Nutrition to Mizoguchi E
文摘The family of mammalian chitinases includes members both with and without glycohydrolase enzymatic activity against chitin, a polymer of N-acetylglucosamine. Chitin is the structural component of fungi, crustaceans, insects and parasitic nematodes, but is completely absent in mammals. Exposure to antigens containing chitin- or chitin-like structures sometimes induces strong T helper type-I responses in mammals, which may be associated with the induction of mammalian chitinases. Chitinase 3-like-1 （CHI3L1）, a member of the mammalian chitinase family, is induced specifically during the course of inflammation in such disorders as inflammatory bowel disease, hepatitis and asthma. In addition, CHI3L1 is expressed and secreted by several types of solid tumors including glioblastoma, colon cancer, breast cancer and malignant melanoma. Although the exact function of CHI3L1 in inflammation and cancer is still largely unknown, CHI3L1 plays a pivotal role in exacerbating the inflammatory processes and in promoting angiogenesis and remodeling of the extracellular matrix. CHI3L1 may be highly involved in the chronic engagement of inflammation which potentiates development of epithelial tumorigenesis presumably by activating the mitogen-activated protein kinase and the protein kinase B signaling pathways. Anti-CHI3L1 antibodies or pan-chitinase inhibitors may have the potential to suppress CHI3Ll-mediated chronic inflammation and the subsequent carcinogenic change in epithelial cells.
文摘As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 （1c2, three alleles） mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.
基金Supported by the National Natural Science Foundation of China(Nos.31070355,31370418)
文摘Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well known. In this study, we conducted experiments on the responses of two toxic Microcystis aeruginosa strains （FACHB-905 and FACHB-915） and their microcystin release in conditions of low temperature （15℃ or 4℃, with illumination） or darkness, and subsequent recovery in standard conditions （25℃ with illumination）. On exposure to 15℃, a small decrease in cell viability was observed, but the cell number increased gradually, suggesting that M. aeruginosa FACHB-905 and FACHB-915 cells seem in general tolerant in 15℃. Interestingly, our results show that a higher carotenoid content and microcystin release potentially enhance the fitness of surviving cells at 15℃. M. aeruginosa cells exposed to lower temperature light stress （4℃） did not completely lose viability and retained the ability to reinitiate growth. In darkness, the maximum quantum yield （Fv/Fm） and the maximum electron transport rate （ETRmax） values and cell viability of M. aeruginosa cells gradually decreased with time. During the recovery period, the photosynthetic efficiency of M. aeruginosa reverted to the normal level. Additionally, M. aeruginosa FACHB-905 and FACHB-915 exposed to low temperature had increased caspase-3-1ike activity and DNA fragmentation, which suggests the occurrence of a type of cell death in M. aeruginosa cells under cold stress similar to programmed cell death. Overall, our findings could confer certain advantages on the Microcystis for surviving cold or dark conditions encountered in the annual cycle, and help explain its repeated occurrence in water blooms in large and shallow lakes.
