The Ludox-QPS method is a newly developed technique,which combines the Ludox HS 40 density centrifugation and quantitative protargol stain,to enumerate marine ciliates with good taxonomic resolution.We tested the meth...The Ludox-QPS method is a newly developed technique,which combines the Ludox HS 40 density centrifugation and quantitative protargol stain,to enumerate marine ciliates with good taxonomic resolution.We tested the method for simultaneous enumeration of diatoms,protozoa and meiobenthos and compared its extraction efficiency for meiobenthos with that of the routine Ludox-TM centrifugation and a modified protocol using Ludox HS 40.We conducted the evaluation with a sample size of 8.3 ml each from sandy,muddy-sand and muddy sediments collected from the intertidal area of the Yellow Sea in summer 2006 and spring 2007.The Ludox-QPS method not only produced high extraction efficiencies of 97±1.3% for diatoms and 97.6±0.8% for ciliates,indicating a reliable enumeration for eukaryotic microbenthos,but also produced excellent extraction efficiencies of on average 97.3% for total meiobenthos,97.9% for nematodes and 97.8% for copepods from sands,muddy sands and mud.By contrast,the routine Ludox-TM centrifugation obtained only about 74% of total meiobenthos abundance with one extraction cycle,and the modified Ludox HS 40 centrifugation yielded on average 93% of total meiobenthos:89.4±2.0% from sands,93±4.1% from muddy sands and 97.1±3.0% from mud.Apart from the sediment type,sample volume was another important factor affecting the extraction efficiency for meiobenthos.The extraction rate was increased to about 96.4% when using the same modified Ludox centrifugation for a 4 ml sediment sample.Besides the excellent extraction efficiency,the Ludox-QPS method obtained higher abundances of meiobenthos,in particular nematodes,than the routine Ludox centrifugation,which frequently resulted in an uncertain loss of small meiobenthos during the sieving process.Statistical analyses demonstrated that there were no significant differences between the meiobenthos communities revealed by the Ludox-QPS method and the modified Ludox HS 40 centrifugation,showing the high efficiency of the Ludox-QPS method for simultaneous enumeration of diatom,protozoa and meiobenthos.Moreover,the comparatively high taxonomic resolution of the method,especially for diatoms and ciliates,makes it feasible to investigate microbial ecology at community level.展开更多
AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality ...AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM), and to evaluate its efficacy. METHODS: Eighty-four patients with postoperative complications or death and 172 patients without postoperative complications, who underwent surgery in our department during the previous 2 years, were retrospectively analyzed by logistic regression. Fifteen indexes were investigated including age, cardiovascular function, respiratory function, blood test results, endocrine function, central nervous system function, hepatic function, renal function, nutritional status, extent of operative trauma, and course of anesthesia. Modified POSSUM (M-POSSUM) was developed using significant risk factors with its efficacy evaluated. RESULTS: The significant risk factors were found to be age, cardiovascular function, respiratory function, hepatic function, renal function, blood test results, endocrine function, nutritional status, duration of operation, intraoperative blood loss, and course of anesthesia. These factors were all included in the scoring system. There were significant differences in the scores between the patients with and without postoperative complications, between the patients died and survived with complications, and between the patients died and survived without complications. The receiver operating characteristic curves showed that the M-POSSUM could accurately predict postoperative complications and mortality.CONCLUSION: M-POSSUM correlates well with postoperative complications and mortality, and is more accurate than POSSUM.展开更多
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No.KZCX2-YW-417)the National Natural Science Foundation of China (No.40576072+1 种基金40706047)the "100 Talents Project" of the Chinese Academy of Sciences
文摘The Ludox-QPS method is a newly developed technique,which combines the Ludox HS 40 density centrifugation and quantitative protargol stain,to enumerate marine ciliates with good taxonomic resolution.We tested the method for simultaneous enumeration of diatoms,protozoa and meiobenthos and compared its extraction efficiency for meiobenthos with that of the routine Ludox-TM centrifugation and a modified protocol using Ludox HS 40.We conducted the evaluation with a sample size of 8.3 ml each from sandy,muddy-sand and muddy sediments collected from the intertidal area of the Yellow Sea in summer 2006 and spring 2007.The Ludox-QPS method not only produced high extraction efficiencies of 97±1.3% for diatoms and 97.6±0.8% for ciliates,indicating a reliable enumeration for eukaryotic microbenthos,but also produced excellent extraction efficiencies of on average 97.3% for total meiobenthos,97.9% for nematodes and 97.8% for copepods from sands,muddy sands and mud.By contrast,the routine Ludox-TM centrifugation obtained only about 74% of total meiobenthos abundance with one extraction cycle,and the modified Ludox HS 40 centrifugation yielded on average 93% of total meiobenthos:89.4±2.0% from sands,93±4.1% from muddy sands and 97.1±3.0% from mud.Apart from the sediment type,sample volume was another important factor affecting the extraction efficiency for meiobenthos.The extraction rate was increased to about 96.4% when using the same modified Ludox centrifugation for a 4 ml sediment sample.Besides the excellent extraction efficiency,the Ludox-QPS method obtained higher abundances of meiobenthos,in particular nematodes,than the routine Ludox centrifugation,which frequently resulted in an uncertain loss of small meiobenthos during the sieving process.Statistical analyses demonstrated that there were no significant differences between the meiobenthos communities revealed by the Ludox-QPS method and the modified Ludox HS 40 centrifugation,showing the high efficiency of the Ludox-QPS method for simultaneous enumeration of diatom,protozoa and meiobenthos.Moreover,the comparatively high taxonomic resolution of the method,especially for diatoms and ciliates,makes it feasible to investigate microbial ecology at community level.
文摘AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM), and to evaluate its efficacy. METHODS: Eighty-four patients with postoperative complications or death and 172 patients without postoperative complications, who underwent surgery in our department during the previous 2 years, were retrospectively analyzed by logistic regression. Fifteen indexes were investigated including age, cardiovascular function, respiratory function, blood test results, endocrine function, central nervous system function, hepatic function, renal function, nutritional status, extent of operative trauma, and course of anesthesia. Modified POSSUM (M-POSSUM) was developed using significant risk factors with its efficacy evaluated. RESULTS: The significant risk factors were found to be age, cardiovascular function, respiratory function, hepatic function, renal function, blood test results, endocrine function, nutritional status, duration of operation, intraoperative blood loss, and course of anesthesia. These factors were all included in the scoring system. There were significant differences in the scores between the patients with and without postoperative complications, between the patients died and survived with complications, and between the patients died and survived without complications. The receiver operating characteristic curves showed that the M-POSSUM could accurately predict postoperative complications and mortality.CONCLUSION: M-POSSUM correlates well with postoperative complications and mortality, and is more accurate than POSSUM.
