The Microchip Imaging Cytometer(MIC)is a class of integrated point-of-care detection systems based on the combination of optical microscopy and flow cytometry.MIC devices have the attributes of portability,cost-effect...The Microchip Imaging Cytometer(MIC)is a class of integrated point-of-care detection systems based on the combination of optical microscopy and flow cytometry.MIC devices have the attributes of portability,cost-effectiveness,and adaptability while providing quantitative measurements to meet the needs of laboratory testing in a variety of healthcare settings.Based on the use of microfluidic chips,MIC requires less sample and can complete sample preparation automatically.Therefore,they can provide quantitative testing results simply using a finger prick specimen.The decreased reagent consumption and reduced form factor also help improve the accessibility and affordability of healthcare services in remote and resource-limited settings.In this article,we review recent developments of the Microchip Imaging Cytometer from the following aspects:clinical applications,microfluidic chip integration,imaging optics,and image acquisition.Following,we provide an outlook of the field and remark on promising technologies that may enable significant progress in the near future.展开更多
Recent studies in oncology have addressed the importance of detecting circulating tumor cell clusters because circulating tumor cell clusters might survive and metastasize more easily than single circulating tumor cel...Recent studies in oncology have addressed the importance of detecting circulating tumor cell clusters because circulating tumor cell clusters might survive and metastasize more easily than single circulating tumor cells.Signals with larger peak widths detected by in vivo flow cytometer(IVFC)have been used to identify cell clusters in previous studies.However,the accuracy of this criterion might be greatly degraded by variance in blood°ow and the rolling behaviors of circulating tumor cells.Here,we propose a criterion and algorithm to distinguish cell clusters from single cells.In this work,we first used area-based and volume-based models for single°uorescent cells.Simulating each model,we analyzed the corresponding morphology of IVFC signals from cell clusters.According to the Rayleigh criterion,the valley between two adjacent peak signals from two distinguishable cells should be lower than 73.5%of the peak values.A novel signal processing algorithm for IVFC was developed based on this criterion.The results showed that cell clusters can be reliably identied using our proposed algorithm.Intravital imaging was also performed to further support our algorithm.With enhanced accuracy,IVFC is a powerful tool to study circulating cell clusters.展开更多
Metastasis is a very complicated multi-step process and accounts for the low survival rate of the cancerous patients.To metastasize,t he malignant cells must detach from the primary tumor and migrate to secondary site...Metastasis is a very complicated multi-step process and accounts for the low survival rate of the cancerous patients.To metastasize,t he malignant cells must detach from the primary tumor and migrate to secondary sites in the body through either blood or lymph circulation.Macrophages appear to be directly involved in tumor progression and metastasis.However,the role of macrophages in affecting cancer metast asis has not been fully elucidated.Here,we have utilized an emerging technique,namely in vivo flow cytometry(IVFC)to study the depletion kinetics of circulating prostate cancer cells in mice and determine how depletion of macrophages by the liposome encapsulated clodronate affects the depletion kinetics.Our results show diferent depletion kinetics of PC-3 cells between the macrophagedeficient group and the control group.The number of circulating tumor cells(CTCs)in the macrophage-deficient group decreases in a slower manner compared to the control mice group.The differences in depletion kinetics indicate that the absence of macrophages facilitates the stay of prostate cancer cells in circulation.In addition,our imaging data suggest that macrophages might be able to arrest,phagocytose and digest PC-3 cells.Therefore,phagocy tosis may mainly contribute to the de-pletion kinetic diferences.The developed methods elaborated here would be useful to study the relationship between macr ophages and tumor metastasis in small animal cancer models.展开更多
A numerical model was proposed to simulate the capillary micro-flow through a fiber bundle. The capillary pressure was predicted by the Young-Laplace equation and the corresponding optimal values of permeability were ...A numerical model was proposed to simulate the capillary micro-flow through a fiber bundle. The capillary pressure was predicted by the Young-Laplace equation and the corresponding optimal values of permeability were found by a trial-and-error method. The empirical Kozeny constants which are dependent on fiber volume fraction were recormnended for the prediction of permeability.展开更多
A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro...A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro-flow channels ranging from 100 μm to 500 μm in width can be produced simultaneously. But, edge chippings easily occur on the rib surface of GCBPP during microplaning due to brittleness of graphite composites. Experimental results show that edge chippings result in the increase of contact resistance between bipolar plate and carbon paper at low compaction force. While the edge chippings scarcely exert influence on the contact resistance at high compaction force. Contrary to conventional view, the edge chippings can significantly improve performance of microfuel cell and big edge chippings outperform small edge chippings. In addition, the influence of technical parameters on edge chippings was investigated in order to obtain big, but not oversized edge chippings.展开更多
The paper is concerned with the micro-flow self-sensing actuators,the work of which is based on the secondary piezoelectric effect. The piezoelectric ceramic stack can yield micro-displacement due to its first inverse...The paper is concerned with the micro-flow self-sensing actuators,the work of which is based on the secondary piezoelectric effect. The piezoelectric ceramic stack can yield micro-displacement due to its first inverse piezoelectric effect. Therefore,we apply this micro-displacement to cell micro-flow injection. Moreover, due to the charge of the secondary direct piezoelectric effect,the piezoelectric ceramic stack is able to detect the force and displacement in the injection by itself. The experiments of first inverse piezoelectric effect and secondary direct piezoelectric effect are conducted. The experiment results show that,subjected to 0- 60 V input,the piezoelectric ceramic stack can generate 13. 45 μm displacement,and control accuracy can achieve 2 nm. It can completely meet the needs of cell micro-flow injection. Also,the experiments demonstrate that the micro-displacement due to the first inverse piezoelectric effect can be well self-sensed by the electric charge due to the secondary direct piezoelectric effect.展开更多
The drying of aqueous poly(ethylene oxide) (PEO) droplet on a substrate at different temperatures was studied. It was found that the contact line receded when the substrate was at a temperature above 60 ℃. Differ...The drying of aqueous poly(ethylene oxide) (PEO) droplet on a substrate at different temperatures was studied. It was found that the contact line receded when the substrate was at a temperature above 60 ℃. Different nucleation behavior and surface profiles of PEO films were found in different droplets drying processes. The rheological properties of aqueous PEO solutions were studied to understand the mechanism of contact line recession and micro-flow in drying aqueous PEO droplets. It was found that at low temperature, the contact line was static because of great viscous stress; while at high temperature, it receded because of great Marangoni force and the decrease of viscous stress. It was indicated that Marangoni convection was inhibited by the outward capillary flow and viscous stress at low temperature, whereas it became dominant at high temperature. Two types of mechanism for surface profiles and nucleation of PEO film from drying droplets are proposed, providing a theoretical guide for polymer solution application in oil and gas foam flooding technology.展开更多
Background: B-cell Acute lymphoblastic leukemia (B-ALL) is a neoplasm of lymphoblasts which are of B-cell lineage typically composed of small to medium sized blast cells, moderately condensed to dispersed chromatin wi...Background: B-cell Acute lymphoblastic leukemia (B-ALL) is a neoplasm of lymphoblasts which are of B-cell lineage typically composed of small to medium sized blast cells, moderately condensed to dispersed chromatin with scanty cytoplasm and inconspicuous nucleoli, involving the bone marrow and/or blood. Methods and materials: This is a prospective cross-sectional study in which 50 blood and/or bone marrow samples of newly diagnosed patients (B-ALL) were tested for immunophenotyping. All samples were prepared for surface and cytoplasmic markers including kappa and lambda human antibody for 10 minutes in dark place and then run by the Flow Cytometer. Results: 64% of the study populations were males and 36% were females. Cases were classified according to immunophenotype and the age into different subtypes and showed the following frequencies: Pro B-ALL (8%), early pre B-ALL (56%), common B-ALL (16%), Pre-B-ALL (14%) and Mature B-ALL (only 6%). Surface immunoglobulin was positive in 10% and negative in 90% of all patients, showing 100% positivity in mature B-ALL and totally negative in other subtypes. While cytoplasmic immunoglobulin was positive in 16% and negative in 84% of all patients and was positive in 100% of Pre-B-ALL and in 50% of mature B-ALL. Surface kappa was more expressed in mature B-ALL than lambda giving a ratio of 2:1, while cytoplasmic kappa:lambda was 6:1 in Pre-B-ALL. Conclusion: Kappa and lambda have important role in B-ALL classification which necessitates their presence in immunophenotyping of B-ALL.展开更多
Plankton size structure is crucial for understanding marine ecosystem dynamics and the associated biogeochemical processes.A fixation step by acid Lugol’s solution has been commonly employed to preserve plankton samp...Plankton size structure is crucial for understanding marine ecosystem dynamics and the associated biogeochemical processes.A fixation step by acid Lugol’s solution has been commonly employed to preserve plankton samples in the field.However,the acid Lugol’s solution can bias the estimation of size structure and the preserved plankton size structure can vary with time.Here,we explore the impact of sample storage time on the size-structure of the plankton community preserved by Lugol’s solution.Two short-term experiments and one long-term experiment were conducted to explore the change of plankton community size structure with the storage time:covering from a week to a month,and to nearly seven months based on particle-size data obtained by continuous Flow Cytometer and Microscope(FlowCAM)measurements.We found a linear change of plankton size with the storage time in short-term periods(less than 3 months)with a decrease of the slope but an increase of the intercept for the normalized biomass size spectrum(NBS S).However,there were opposite trends for NBSS with increasing slope but decreasing intercept after3 months.The potential causes of the distinct patterns of the NBSS parameters are addressed in terms of the interplay between particle aggregation and fragmentation.We found large changes in plankton biovolume and abundance among different size classes,which may indicate a distinct effect of acid Lugol’s solution on various plankton size classes.The mechanism driving temporal change in the size-structure of the Lugolfixed plankton community was further discussed in terms of particle aggregation and fragmentation.Finally,we emphasize that the effect of storage time should be taken into account when interpreting or comparing data of plankton community acquired from samples with various storage durations.展开更多
Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity beds.The fluidization status,the bubbling or turbulent flow regime and the transition in between,deter...Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity beds.The fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the system performance in practical applications.Though the convoluted hydrodynamics are quantitively evaluated through numerous data-processing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent regime.Accordingly,this study was to exploit a coupling data processing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet multiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent fluidization.The transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).The results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bottom section.The wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency band.These sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics in the fluidized bed.The micro-scale signal has the characteristic information of bubbling fluidization,and the characteristic information of turbulent fluidization is mainly represented by the meso-scale signal.This work provides a systematic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis in this sector.展开更多
The flow cytometer was used to compare the DNA content in the blood cells and sperm in the new type of tetraploid (G 1×4n) and in red crucian carp used as the control. The new type of tetraploid (G 1×4n) was...The flow cytometer was used to compare the DNA content in the blood cells and sperm in the new type of tetraploid (G 1×4n) and in red crucian carp used as the control. The new type of tetraploid (G 1×4n) was produced by mating the diploid female gynogenetic progeny (first generation,G 1) of the tetraploid hybrid of red crucain carp × common carp, with the male of the tetraploid hybrid. Chromosome spreads from the kidney tissue in the new type of tetraploid were also examined. The results from the flow cytometer indicated that the mean DNA content of the diploid sperm produced by the new type of tetraploid was twice that of the haploid sperm generated by the diploid red crucian carp, and the mean DNA content of the blood cells in the tetraploid was twice that in red crucian carp. Examination of chromosome spreads from the kidney tissue also indicated that the examined samples of the G 1×4n were tetraploids with 200 chromosomes, which was in agreement with the results of the DNA content measurements from the sperm and the blood cells. The present study proved that the new type of tetraploids was able to produce normal diploid sperm, which fertilized diploid eggs from the new type of tetraploid to produce viable offspring. The flow cytometer was proved to be one of the accurate, secure and simple methods to distinguish the different ploidy fish in blood cells and sperm by measuring their DNA content .展开更多
基金Natural Sciences and Engineering Research Council of Canada (NSERC)Ontario Research Fund (ORF)the India-Canada Centre for Innovative Multidisciplinary Partnerships to Accelerate Community Transformation and Sustainability (IC-IM-PACTS)
文摘The Microchip Imaging Cytometer(MIC)is a class of integrated point-of-care detection systems based on the combination of optical microscopy and flow cytometry.MIC devices have the attributes of portability,cost-effectiveness,and adaptability while providing quantitative measurements to meet the needs of laboratory testing in a variety of healthcare settings.Based on the use of microfluidic chips,MIC requires less sample and can complete sample preparation automatically.Therefore,they can provide quantitative testing results simply using a finger prick specimen.The decreased reagent consumption and reduced form factor also help improve the accessibility and affordability of healthcare services in remote and resource-limited settings.In this article,we review recent developments of the Microchip Imaging Cytometer from the following aspects:clinical applications,microfluidic chip integration,imaging optics,and image acquisition.Following,we provide an outlook of the field and remark on promising technologies that may enable significant progress in the near future.
基金the National Science Fund for Distinguished Young Scholars(Grant No.61425006)Program of Shanghai Technology Research Leader(Grant No.17XD1402200).
文摘Recent studies in oncology have addressed the importance of detecting circulating tumor cell clusters because circulating tumor cell clusters might survive and metastasize more easily than single circulating tumor cells.Signals with larger peak widths detected by in vivo flow cytometer(IVFC)have been used to identify cell clusters in previous studies.However,the accuracy of this criterion might be greatly degraded by variance in blood°ow and the rolling behaviors of circulating tumor cells.Here,we propose a criterion and algorithm to distinguish cell clusters from single cells.In this work,we first used area-based and volume-based models for single°uorescent cells.Simulating each model,we analyzed the corresponding morphology of IVFC signals from cell clusters.According to the Rayleigh criterion,the valley between two adjacent peak signals from two distinguishable cells should be lower than 73.5%of the peak values.A novel signal processing algorithm for IVFC was developed based on this criterion.The results showed that cell clusters can be reliably identied using our proposed algorithm.Intravital imaging was also performed to further support our algorithm.With enhanced accuracy,IVFC is a powerful tool to study circulating cell clusters.
基金supported by the National Basic Research Program of China(973Program,2011CB910404 and 2012CB966800)China National Natural Science Foundation(30901432 and 30972949)+2 种基金the Chinese Ministry of Education(109056)Program for New Century Excellent Talents in University Award(NCET-08-0131)Shanghai Science and Tech-nology Committee(11DZ2211000).
文摘Metastasis is a very complicated multi-step process and accounts for the low survival rate of the cancerous patients.To metastasize,t he malignant cells must detach from the primary tumor and migrate to secondary sites in the body through either blood or lymph circulation.Macrophages appear to be directly involved in tumor progression and metastasis.However,the role of macrophages in affecting cancer metast asis has not been fully elucidated.Here,we have utilized an emerging technique,namely in vivo flow cytometry(IVFC)to study the depletion kinetics of circulating prostate cancer cells in mice and determine how depletion of macrophages by the liposome encapsulated clodronate affects the depletion kinetics.Our results show diferent depletion kinetics of PC-3 cells between the macrophagedeficient group and the control group.The number of circulating tumor cells(CTCs)in the macrophage-deficient group decreases in a slower manner compared to the control mice group.The differences in depletion kinetics indicate that the absence of macrophages facilitates the stay of prostate cancer cells in circulation.In addition,our imaging data suggest that macrophages might be able to arrest,phagocytose and digest PC-3 cells.Therefore,phagocy tosis may mainly contribute to the de-pletion kinetic diferences.The developed methods elaborated here would be useful to study the relationship between macr ophages and tumor metastasis in small animal cancer models.
文摘A numerical model was proposed to simulate the capillary micro-flow through a fiber bundle. The capillary pressure was predicted by the Young-Laplace equation and the corresponding optimal values of permeability were found by a trial-and-error method. The empirical Kozeny constants which are dependent on fiber volume fraction were recormnended for the prediction of permeability.
基金Project(51075155)supported by the National Natural Science Foundation of ChinaProject(2013ZZ017)supported by the Fundamental Research Funds for the Central Universities,China
文摘A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro-flow channels ranging from 100 μm to 500 μm in width can be produced simultaneously. But, edge chippings easily occur on the rib surface of GCBPP during microplaning due to brittleness of graphite composites. Experimental results show that edge chippings result in the increase of contact resistance between bipolar plate and carbon paper at low compaction force. While the edge chippings scarcely exert influence on the contact resistance at high compaction force. Contrary to conventional view, the edge chippings can significantly improve performance of microfuel cell and big edge chippings outperform small edge chippings. In addition, the influence of technical parameters on edge chippings was investigated in order to obtain big, but not oversized edge chippings.
基金Sponsored by the Youths Science Foundation of Heilongjiang Province(Grant No.QC08C09)the Educational Committee Science Foundation of Heilongjiang Province(Grant No.11541272)
文摘The paper is concerned with the micro-flow self-sensing actuators,the work of which is based on the secondary piezoelectric effect. The piezoelectric ceramic stack can yield micro-displacement due to its first inverse piezoelectric effect. Therefore,we apply this micro-displacement to cell micro-flow injection. Moreover, due to the charge of the secondary direct piezoelectric effect,the piezoelectric ceramic stack is able to detect the force and displacement in the injection by itself. The experiments of first inverse piezoelectric effect and secondary direct piezoelectric effect are conducted. The experiment results show that,subjected to 0- 60 V input,the piezoelectric ceramic stack can generate 13. 45 μm displacement,and control accuracy can achieve 2 nm. It can completely meet the needs of cell micro-flow injection. Also,the experiments demonstrate that the micro-displacement due to the first inverse piezoelectric effect can be well self-sensed by the electric charge due to the secondary direct piezoelectric effect.
文摘The drying of aqueous poly(ethylene oxide) (PEO) droplet on a substrate at different temperatures was studied. It was found that the contact line receded when the substrate was at a temperature above 60 ℃. Different nucleation behavior and surface profiles of PEO films were found in different droplets drying processes. The rheological properties of aqueous PEO solutions were studied to understand the mechanism of contact line recession and micro-flow in drying aqueous PEO droplets. It was found that at low temperature, the contact line was static because of great viscous stress; while at high temperature, it receded because of great Marangoni force and the decrease of viscous stress. It was indicated that Marangoni convection was inhibited by the outward capillary flow and viscous stress at low temperature, whereas it became dominant at high temperature. Two types of mechanism for surface profiles and nucleation of PEO film from drying droplets are proposed, providing a theoretical guide for polymer solution application in oil and gas foam flooding technology.
文摘Background: B-cell Acute lymphoblastic leukemia (B-ALL) is a neoplasm of lymphoblasts which are of B-cell lineage typically composed of small to medium sized blast cells, moderately condensed to dispersed chromatin with scanty cytoplasm and inconspicuous nucleoli, involving the bone marrow and/or blood. Methods and materials: This is a prospective cross-sectional study in which 50 blood and/or bone marrow samples of newly diagnosed patients (B-ALL) were tested for immunophenotyping. All samples were prepared for surface and cytoplasmic markers including kappa and lambda human antibody for 10 minutes in dark place and then run by the Flow Cytometer. Results: 64% of the study populations were males and 36% were females. Cases were classified according to immunophenotype and the age into different subtypes and showed the following frequencies: Pro B-ALL (8%), early pre B-ALL (56%), common B-ALL (16%), Pre-B-ALL (14%) and Mature B-ALL (only 6%). Surface immunoglobulin was positive in 10% and negative in 90% of all patients, showing 100% positivity in mature B-ALL and totally negative in other subtypes. While cytoplasmic immunoglobulin was positive in 16% and negative in 84% of all patients and was positive in 100% of Pre-B-ALL and in 50% of mature B-ALL. Surface kappa was more expressed in mature B-ALL than lambda giving a ratio of 2:1, while cytoplasmic kappa:lambda was 6:1 in Pre-B-ALL. Conclusion: Kappa and lambda have important role in B-ALL classification which necessitates their presence in immunophenotyping of B-ALL.
基金Supported by the Guangdong Province Special Support Plan for Leading Talents(No.2019TX05H216)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0305)+1 种基金the National Natural Science Foundation of China(No.41906132)the Science and Technology Program of Guangzhou(No.202102021229)。
文摘Plankton size structure is crucial for understanding marine ecosystem dynamics and the associated biogeochemical processes.A fixation step by acid Lugol’s solution has been commonly employed to preserve plankton samples in the field.However,the acid Lugol’s solution can bias the estimation of size structure and the preserved plankton size structure can vary with time.Here,we explore the impact of sample storage time on the size-structure of the plankton community preserved by Lugol’s solution.Two short-term experiments and one long-term experiment were conducted to explore the change of plankton community size structure with the storage time:covering from a week to a month,and to nearly seven months based on particle-size data obtained by continuous Flow Cytometer and Microscope(FlowCAM)measurements.We found a linear change of plankton size with the storage time in short-term periods(less than 3 months)with a decrease of the slope but an increase of the intercept for the normalized biomass size spectrum(NBS S).However,there were opposite trends for NBSS with increasing slope but decreasing intercept after3 months.The potential causes of the distinct patterns of the NBSS parameters are addressed in terms of the interplay between particle aggregation and fragmentation.We found large changes in plankton biovolume and abundance among different size classes,which may indicate a distinct effect of acid Lugol’s solution on various plankton size classes.The mechanism driving temporal change in the size-structure of the Lugolfixed plankton community was further discussed in terms of particle aggregation and fragmentation.Finally,we emphasize that the effect of storage time should be taken into account when interpreting or comparing data of plankton community acquired from samples with various storage durations.
基金support from the China Scholarship Council Foundation,and the Science Foundation of China University of Petroleum,Beijing(grant No.2462015YQ0301)。
文摘Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity beds.The fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the system performance in practical applications.Though the convoluted hydrodynamics are quantitively evaluated through numerous data-processing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent regime.Accordingly,this study was to exploit a coupling data processing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet multiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent fluidization.The transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).The results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bottom section.The wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency band.These sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics in the fluidized bed.The micro-scale signal has the characteristic information of bubbling fluidization,and the characteristic information of turbulent fluidization is mainly represented by the meso-scale signal.This work provides a systematic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis in this sector.
基金国家自然科学基金项目 (No 30170733 No 30330480)教育部跨世纪优秀人才培养基金 (No 200248) 项目资助~~
文摘The flow cytometer was used to compare the DNA content in the blood cells and sperm in the new type of tetraploid (G 1×4n) and in red crucian carp used as the control. The new type of tetraploid (G 1×4n) was produced by mating the diploid female gynogenetic progeny (first generation,G 1) of the tetraploid hybrid of red crucain carp × common carp, with the male of the tetraploid hybrid. Chromosome spreads from the kidney tissue in the new type of tetraploid were also examined. The results from the flow cytometer indicated that the mean DNA content of the diploid sperm produced by the new type of tetraploid was twice that of the haploid sperm generated by the diploid red crucian carp, and the mean DNA content of the blood cells in the tetraploid was twice that in red crucian carp. Examination of chromosome spreads from the kidney tissue also indicated that the examined samples of the G 1×4n were tetraploids with 200 chromosomes, which was in agreement with the results of the DNA content measurements from the sperm and the blood cells. The present study proved that the new type of tetraploids was able to produce normal diploid sperm, which fertilized diploid eggs from the new type of tetraploid to produce viable offspring. The flow cytometer was proved to be one of the accurate, secure and simple methods to distinguish the different ploidy fish in blood cells and sperm by measuring their DNA content .