The marine diatom Phaeodactylum tricornutum is a polymorphological, ecologically significant, and well-studied model of unicellular microalga. This diatom can accumulate diverse important metabolites. Herein, we cultu...The marine diatom Phaeodactylum tricornutum is a polymorphological, ecologically significant, and well-studied model of unicellular microalga. This diatom can accumulate diverse important metabolites. Herein, we cultured P. tricornutum in an internally installed tie-piece flat-plate photobioreactor under 14.5 m mol L^(-1)(high nitrogen, HN) and 2.9 m mol L^(-1)(low nitrogen, LN) of KNO_3 and assessed its time-resolved changes in biochemical compositions. The results showed that HN was inductive to accumulate high biomass(4.1 g L^(-1)). However, the LN condition could accelerate lipid accumulation in P. tricornutum. The maximum total lipid(TL) content under LN was up to 42.5% of biomass on day 12. Finally, neutral lipids(NLs) were 63.8% and 75.7% of TLs under HN and LN, respectively. The content of EPA ranged from 2.3% to 1.5% of dry weight during the growth period under the two culture conditions. Peak volumetric lipid productivity of 128.4 mg L^(-1)d^(-1) was achieved in the HN group(on day 9). The highest volumetric productivity values of EPA, chrysolaminarin, and fucoxanthin were obtained in the exponential phase(on day 6) under HN, which were 9.6, 93.6, and 4.7 mg L^(-1)d^(-1), respectively. In conclusion, extractable amounts of lipids, EPA, fucoxanthin, and chrysolaminarin could be obtained from P. tricornutum by regulating the culture conditions.展开更多
AIM:To investigate the expression and localization of paxillin in rat pancreas during development. METHODS:Pancreata from Sprague Dawley rat fetuses, embryos, young animals, and adult animals were used in this study. ...AIM:To investigate the expression and localization of paxillin in rat pancreas during development. METHODS:Pancreata from Sprague Dawley rat fetuses, embryos, young animals, and adult animals were used in this study. Expression levels of paxillin in pancreata of different development stages were detected by reverse transcription polymerase chain reaction and Western blotting. To identify the cell location of paxillin in the developing rat pancreas, immunohistochemistry and double-immunofluorescent staining were performed using antibodies for specific cell markers and paxillin, respectively. RESULTS:The highest paxillin mRNA level was detected at E15.5 (embryo day 15.5) following a decrease in the later developmental periods (P < 0.05 vs E18.5, P0 and adult, respectively), and a progressively increased paxillin protein expression through the transition from E15.5 to adult was detected. The paxillin positive staining was mainly localized in rat islets of Langerhans at each stage tested during pancreas development. CONCLUSION:The dynamic expression of paxillin in rat pancreas from different stages indicates that paxillin might be involved in some aspects of pancreatic development.展开更多
基金supported by the Natural Science Foundation of China (No. 31170337)the National High Technology Research and Development Program of China (863 Program) (No. 2013AA 065805)+1 种基金the National Basic Research Program of China (973 Program) (No. 2011CB2009001)the Special Program for Low-Carbon, Reform and Development Commission of Guangdong Province (No. 2011-051)
文摘The marine diatom Phaeodactylum tricornutum is a polymorphological, ecologically significant, and well-studied model of unicellular microalga. This diatom can accumulate diverse important metabolites. Herein, we cultured P. tricornutum in an internally installed tie-piece flat-plate photobioreactor under 14.5 m mol L^(-1)(high nitrogen, HN) and 2.9 m mol L^(-1)(low nitrogen, LN) of KNO_3 and assessed its time-resolved changes in biochemical compositions. The results showed that HN was inductive to accumulate high biomass(4.1 g L^(-1)). However, the LN condition could accelerate lipid accumulation in P. tricornutum. The maximum total lipid(TL) content under LN was up to 42.5% of biomass on day 12. Finally, neutral lipids(NLs) were 63.8% and 75.7% of TLs under HN and LN, respectively. The content of EPA ranged from 2.3% to 1.5% of dry weight during the growth period under the two culture conditions. Peak volumetric lipid productivity of 128.4 mg L^(-1)d^(-1) was achieved in the HN group(on day 9). The highest volumetric productivity values of EPA, chrysolaminarin, and fucoxanthin were obtained in the exponential phase(on day 6) under HN, which were 9.6, 93.6, and 4.7 mg L^(-1)d^(-1), respectively. In conclusion, extractable amounts of lipids, EPA, fucoxanthin, and chrysolaminarin could be obtained from P. tricornutum by regulating the culture conditions.
基金Supported by The National Natural Science Foundation of China,Grant No.81070620International Cooperation Project of Jiangsu Province,Grant No.BK2007117 and BZ2008062
文摘AIM:To investigate the expression and localization of paxillin in rat pancreas during development. METHODS:Pancreata from Sprague Dawley rat fetuses, embryos, young animals, and adult animals were used in this study. Expression levels of paxillin in pancreata of different development stages were detected by reverse transcription polymerase chain reaction and Western blotting. To identify the cell location of paxillin in the developing rat pancreas, immunohistochemistry and double-immunofluorescent staining were performed using antibodies for specific cell markers and paxillin, respectively. RESULTS:The highest paxillin mRNA level was detected at E15.5 (embryo day 15.5) following a decrease in the later developmental periods (P < 0.05 vs E18.5, P0 and adult, respectively), and a progressively increased paxillin protein expression through the transition from E15.5 to adult was detected. The paxillin positive staining was mainly localized in rat islets of Langerhans at each stage tested during pancreas development. CONCLUSION:The dynamic expression of paxillin in rat pancreas from different stages indicates that paxillin might be involved in some aspects of pancreatic development.
