Microalgae can be cultivated for producing high-valued products through the production of enzymes to offset the cost of CO_(2) sequestration,providing financial incentives.The viability of algae in the photobioreactor...Microalgae can be cultivated for producing high-valued products through the production of enzymes to offset the cost of CO_(2) sequestration,providing financial incentives.The viability of algae in the photobioreactor needs to be monitored to ensure biologically active live cells.In this study,we explored a simple fluorometry method for differentiation of live and dead algal cells in photobioreactors by fluorescein diacetate(FDA)and propidium iodide(PI)fluorescence staining.FDA stains fluorescent green to the living cells while PI stains the dead cells,allowing the discrimination of live and dead cells.The method was evaluated using two green algae and two strains of cyanobacteria grown in shake flasks and a continuously stirred photobioreactor.The method was found applicable for Chlorella pyrenoidosa and Synechococcus 7002 but was not applicable for the cultures of Scenedesmus dimorphus and Synechococcus elongatus 7942.We conclude that FDA is a good stain for monitoring live algal cells in photobioreactors but its applicability to individual species of algae must be evaluated.展开更多
Objective To estimate the predictive value of double fluorescence [acridine orange （AO）/propidium iodide （PI）] staining results for fertilization rate and clinical outcomes and analyze the correlation between th...Objective To estimate the predictive value of double fluorescence [acridine orange （AO）/propidium iodide （PI）] staining results for fertilization rate and clinical outcomes and analyze the correlation between the results of AO/P1 staining and sperm apoptosis. Methods A prospective study was carried out, 235 infertile couples remedied using traditional in vitro fertilization （IVF） were included. Semen collected from 235 patients were stained by fluorescence dye, AO and PL at the same time the spermatozoa apoptosis rate was calculated by using flow cytometry to detect the rate of Annexin V＋/ PI- . The result of fluorescence was divided into 3 groups as green （G）, yellow （Y） and red （R） according to the color of fluorescence. The correlation between the percent of the 3 colors and clinical outcomes and spermatozoa apoptosis rate was evaluated. Results Significant negative correlation was observed between the percentage of Y and fertilization rate （r= -0.42, P=0.04）, no significant correlation was observed between the percentage of G, R and fertilization rate. The percentage of G, Y, R was not significantly different between pregnant patients and non-pregnant patients, respectiw,ly, while the percentage of Y was significant different between miscarriage patients and liveborn patients （r=0.6L P=0.01） and no significant difference exist in the percentage of G and R between liveborn patients and miscarriage patients. There was a significant positive correlation between the percentage of Y and the rate of Annexin V＋/ PI （r=0.53, P=0.04）, and no significant correlation was shown between the percentage of G, R and the rate of Annexin V＋/ PI-.Conclusion The percentage of yellow group of double fluorescence （AO/PI） staining will affect the fertilization rate and the miscarriage rate, and this group of spermatozoa may be connected with the spermatozoa apoptosis.展开更多
基金the Natural Sciences and Engineering Research Council(NSERC)of Canada in the form of a strategic grant(STPGP 380768-09)。
文摘Microalgae can be cultivated for producing high-valued products through the production of enzymes to offset the cost of CO_(2) sequestration,providing financial incentives.The viability of algae in the photobioreactor needs to be monitored to ensure biologically active live cells.In this study,we explored a simple fluorometry method for differentiation of live and dead algal cells in photobioreactors by fluorescein diacetate(FDA)and propidium iodide(PI)fluorescence staining.FDA stains fluorescent green to the living cells while PI stains the dead cells,allowing the discrimination of live and dead cells.The method was evaluated using two green algae and two strains of cyanobacteria grown in shake flasks and a continuously stirred photobioreactor.The method was found applicable for Chlorella pyrenoidosa and Synechococcus 7002 but was not applicable for the cultures of Scenedesmus dimorphus and Synechococcus elongatus 7942.We conclude that FDA is a good stain for monitoring live algal cells in photobioreactors but its applicability to individual species of algae must be evaluated.
基金supported by a grant from STCSM (Subject No.:074207002)
文摘Objective To estimate the predictive value of double fluorescence [acridine orange （AO）/propidium iodide （PI）] staining results for fertilization rate and clinical outcomes and analyze the correlation between the results of AO/P1 staining and sperm apoptosis. Methods A prospective study was carried out, 235 infertile couples remedied using traditional in vitro fertilization （IVF） were included. Semen collected from 235 patients were stained by fluorescence dye, AO and PL at the same time the spermatozoa apoptosis rate was calculated by using flow cytometry to detect the rate of Annexin V＋/ PI- . The result of fluorescence was divided into 3 groups as green （G）, yellow （Y） and red （R） according to the color of fluorescence. The correlation between the percent of the 3 colors and clinical outcomes and spermatozoa apoptosis rate was evaluated. Results Significant negative correlation was observed between the percentage of Y and fertilization rate （r= -0.42, P=0.04）, no significant correlation was observed between the percentage of G, R and fertilization rate. The percentage of G, Y, R was not significantly different between pregnant patients and non-pregnant patients, respectiw,ly, while the percentage of Y was significant different between miscarriage patients and liveborn patients （r=0.6L P=0.01） and no significant difference exist in the percentage of G and R between liveborn patients and miscarriage patients. There was a significant positive correlation between the percentage of Y and the rate of Annexin V＋/ PI （r=0.53, P=0.04）, and no significant correlation was shown between the percentage of G, R and the rate of Annexin V＋/ PI-.Conclusion The percentage of yellow group of double fluorescence （AO/PI） staining will affect the fertilization rate and the miscarriage rate, and this group of spermatozoa may be connected with the spermatozoa apoptosis.
