Objective Findings from the previous studies have suggested a relationship between ectonucleotide pyrophosphatase /phosphodiesterase 1 (ENPP‐1) or plasma cell membrane glycoprotein 1 (PC‐1) gene single nucleotid...Objective Findings from the previous studies have suggested a relationship between ectonucleotide pyrophosphatase /phosphodiesterase 1 (ENPP‐1) or plasma cell membrane glycoprotein 1 (PC‐1) gene single nucleotide polymorphism (K121Q, rs1044498) and genetic susceptibility to obesity. However, such relationship is not reproduced by some currently available studies. In this context, the present study is aimed to quantitatively analyze the association of K121Q variant with obesity in all published case‐control studies in European adult populations. Methods Published literature from PubMed, EMBASE, and ISI web of science databases were retrieved. The studies evaluating the association of ENPP1/PC1 gene K121Q polymorphism with obesity were included, in which sufficient data were presented to calculate the odds ratio (OR) with 95% confidence intervals (CIs). Results Ten case‐control studies meeting the inclusion criteria identified a total of 24,324 subjects including 11,372 obese and 12,952 control subjects. The meta‐analysis results showed a statistically significant association of K121Q with obesity [OR (95%CI): 1.25 (1.04‐1.52) P=0.021] under a recessive model of inheritance (QQ vs. KK+KQ) without heterogeneity or publication bias. Conclusions The results from the present study have indicated that ENPP1/PC1 Q121 variant may increase the risk of obesity and that more well‐designed studies based on a larger population will be required to further evaluate the role of ENPP1/PC1 gene K121Q polymorphism in obesity and other related metabolic syndromes.展开更多
Microalgal lipids are regarded as main future feedstock of biofuels for its higher efficiency of accumulation and sus- tainable production. In order to investigate the effect of various nitrogen to phosphorus ratios o...Microalgal lipids are regarded as main future feedstock of biofuels for its higher efficiency of accumulation and sus- tainable production. In order to investigate the effect of various nitrogen to phosphorus ratios on cells growth, chlorophyll content and accumulation of lipids in Dunaliella tertiolecta, experiments were carried out in modified microalgal medium with inorganic nitrogen (nitrate-nitrogen) or organic nitrogen (urea-nitrogen) as the sole nitrogen source at initial N:P ratios ranging from 1:1 to 32:1. The favorable N:P of 16:1 in the nitrate-N or urea-N medium yielded the maximum cell density and specific growth rate. Decrease in chlorophyll content were observed at the N:P of 4:1 in both nitrate-N and urea-N cultures. It was also observed that the maximum lipids concentration was obtained at the N:P of 4:1 in both nitrate and urea nutrient medium. The lipid productivity and lipid content of cultures in the urea-N medium at the N:P of 4: lwere markedly higher than those from cultures with other N:P ratios (p〈 0.05). The results of this work illustrate the possibility that higher ratios of nitrogen to phosphorus have enhancing effect on cells growth of D. tertiolecta. Conversely, higher lipid accumulation is associated with a decrease in chlorophyll content under lower ratios of nitro- gen to phosphorus. The results confirm the hypothesis of this study that a larger metabolic flux has been channeled to lipid accumu- lation in D. tertiolecta cells when the ratios of nitrogen to phosphorus drop below a critical level.展开更多
文摘Objective Findings from the previous studies have suggested a relationship between ectonucleotide pyrophosphatase /phosphodiesterase 1 (ENPP‐1) or plasma cell membrane glycoprotein 1 (PC‐1) gene single nucleotide polymorphism (K121Q, rs1044498) and genetic susceptibility to obesity. However, such relationship is not reproduced by some currently available studies. In this context, the present study is aimed to quantitatively analyze the association of K121Q variant with obesity in all published case‐control studies in European adult populations. Methods Published literature from PubMed, EMBASE, and ISI web of science databases were retrieved. The studies evaluating the association of ENPP1/PC1 gene K121Q polymorphism with obesity were included, in which sufficient data were presented to calculate the odds ratio (OR) with 95% confidence intervals (CIs). Results Ten case‐control studies meeting the inclusion criteria identified a total of 24,324 subjects including 11,372 obese and 12,952 control subjects. The meta‐analysis results showed a statistically significant association of K121Q with obesity [OR (95%CI): 1.25 (1.04‐1.52) P=0.021] under a recessive model of inheritance (QQ vs. KK+KQ) without heterogeneity or publication bias. Conclusions The results from the present study have indicated that ENPP1/PC1 Q121 variant may increase the risk of obesity and that more well‐designed studies based on a larger population will be required to further evaluate the role of ENPP1/PC1 gene K121Q polymorphism in obesity and other related metabolic syndromes.
基金partially supported by Tianjin Marine Revitalization Plan of Science and Technology (No.KJXH2013-16) from Tianjin Oceanic Administration,China
文摘Microalgal lipids are regarded as main future feedstock of biofuels for its higher efficiency of accumulation and sus- tainable production. In order to investigate the effect of various nitrogen to phosphorus ratios on cells growth, chlorophyll content and accumulation of lipids in Dunaliella tertiolecta, experiments were carried out in modified microalgal medium with inorganic nitrogen (nitrate-nitrogen) or organic nitrogen (urea-nitrogen) as the sole nitrogen source at initial N:P ratios ranging from 1:1 to 32:1. The favorable N:P of 16:1 in the nitrate-N or urea-N medium yielded the maximum cell density and specific growth rate. Decrease in chlorophyll content were observed at the N:P of 4:1 in both nitrate-N and urea-N cultures. It was also observed that the maximum lipids concentration was obtained at the N:P of 4:1 in both nitrate and urea nutrient medium. The lipid productivity and lipid content of cultures in the urea-N medium at the N:P of 4: lwere markedly higher than those from cultures with other N:P ratios (p〈 0.05). The results of this work illustrate the possibility that higher ratios of nitrogen to phosphorus have enhancing effect on cells growth of D. tertiolecta. Conversely, higher lipid accumulation is associated with a decrease in chlorophyll content under lower ratios of nitro- gen to phosphorus. The results confirm the hypothesis of this study that a larger metabolic flux has been channeled to lipid accumu- lation in D. tertiolecta cells when the ratios of nitrogen to phosphorus drop below a critical level.