Which to Choose For Sperm Sorting? Swim up Versus Density Gradient: A Sibling Oocyte Study

Abstract Study question To compare the effect of sperm preparation methods on the DFI of semen sample for patients undergoing ICSI. Summary answer On comparing the results, microfluidic sperm sorting yielded sperms with significantly less DFI as compared to density gradient method of sperm preparation. What is known already The DNA integrity of the sperm plays an important role to ensure formation of good quality embryos with increased potential of fertilization, growth and ultimately implantation.. Centrifugation has shown to add stress to the sperm and leading to DNA damage, therefore there is a need to develop techniques of sperm preparation which help in retrieving as many sperms with intact DNA from the unprocessed sample as possible. Microfludic is fluid dynamic based technique of sperm preparation. in this study, we evaluated if microfluidic sperm sorter can recover motile sperm with better DNA integrity compared to density gradient preparation method. Study design, size, duration Prospective randomized study conducted in 80 patients undergoing IVF-ICSI with normal semen parameters (based WHO criteria 2010). DFI was done using Sperm Chromatin Dispersion (SCD) test in split semen samples prepared by microfluidic sperm sorter and density gradient method. Sperm morphology and motility were also recorded and evaluated based on the WHO 2010 criteria. Participants/materials, setting, methods Semen parameters of the sample were assessed by microscopic examination. DFI of each unprocessed sample was carried out using SCD test, following that the sample was split and sperm preparation was done using microfluidic sperm sorter and density gradient. the recovered sperm were tested for DFI and the results were compared. Main results and the role of chance Mean DFI in unprocessed semen samples was 23%. the analysis of split semen samples post preparation showed that the DFI was significantly reduced with the use of microfluidic sperm sorter (mean DFI 0.6%) as compared to density gradient (mean DFI 9%). Limitations, reasons for caution A major limitation of the microfluidic sperm sorter is the use sperm concentration and motility of the semen sample. In oligospermic and asthenospermic samples, density gradient is the preferred method of preparation. Lack of data showing improvement in clinical outcomes with reduced DFI is also a major limitation. Wider implications of the findings: Microfluidics has shown to significantly reduce the DFI of the semen sample, it requires no extra equipment and cost and is relatively easy to pick up. Density gradient method of sperm preparation continues to be the preferred method due to its versatility and recovery of good quality sperm. Trial registration number Not applicable

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Comparison of microfluid sperm sorting chip and density gradient methods for use in intrauterine insemination cycles

Fertility and Sterility ◽

10.1016/j.fertnstert.2019.06.037 ◽

2019 ◽

Vol 112 (5) ◽

pp. 842-848.e1 ◽

Cited By ~ 2

Author(s):

Funda Gode ◽

Taylan Bodur ◽

Fatma Gunturkun ◽

Ali Sami Gurbuz ◽

Burcu Tamer ◽

...

Keyword(s):

Density Gradient ◽

Intrauterine Insemination ◽

Gradient Methods ◽

Sperm Sorting

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Activated Prominences; Mechanisms for Activation and Eruption

International Astronomical Union Colloquium ◽

10.1017/s0252921100065714 ◽

1979 ◽

Vol 44 ◽

pp. 307-313

Author(s):

D.S. Spicer

Keyword(s):

Pressure Gradient ◽

Density Gradient ◽

Current Density ◽

Convective Instability ◽

Tearing Mode ◽

Magnetic Shear ◽

Long Wavelength ◽

Ideal Mhd ◽

Gradient Change ◽

Accelerated Particles

A possible relationship between the hot prominence transition sheath, increased internal turbulent and/or helical motion prior to prominence eruption and the prominence eruption (“disparition brusque”) is discussed. The associated darkening of the filament or brightening of the prominence is interpreted as a change in the prominence’s internal pressure gradient which, if of the correct sign, can lead to short wavelength turbulent convection within the prominence. Associated with such a pressure gradient change may be the alteration of the current density gradient within the prominence. Such a change in the current density gradient may also be due to the relative motion of the neighbouring plages thereby increasing the magnetic shear within the prominence, i.e., steepening the current density gradient. Depending on the magnitude of the current density gradient, i.e., magnetic shear, disruption of the prominence can occur by either a long wavelength ideal MHD helical (“kink”) convective instability and/or a long wavelength resistive helical (“kink”) convective instability (tearing mode). The long wavelength ideal MHD helical instability will lead to helical rotation and thus unwinding due to diamagnetic effects and plasma ejections due to convection. The long wavelength resistive helical instability will lead to both unwinding and plasma ejections, but also to accelerated plasma flow, long wavelength magnetic field filamentation, accelerated particles and long wavelength heating internal to the prominence.

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Uranyl Acetate and Rotary Shadowing to Increase the Contrast of Small Aggregated Virus Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064037 ◽

1969 ◽

Vol 27 ◽

pp. 424-425

Author(s):

Lee F. Ellis ◽

Richard M. Van Frank ◽

Walter J. Kleinschmidt

Keyword(s):

Electron Microscopy ◽

Tissue Culture ◽

Density Gradient ◽

Density Gradient Centrifugation ◽

Gradient Centrifugation ◽

Uranyl Acetate ◽

Interferon Inducer ◽

Virus Particles ◽

Staining Methods ◽

Rotary Shadowing

The extract from Penicillum stoliniferum, known as statolon, has been purified by density gradient centrifugation. These centrifuge fractions contained virus particles that are an interferon inducer in mice or in tissue culture. Highly purified preparations of these particles are difficult to enumerate by electron microscopy because of aggregation. Therefore a study of staining methods was undertaken.

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The Combining Ability of Glycoproteins IIb, IIIa and Ca2+ in EDTA-Treated Nonaggregable Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1665326 ◽

1983 ◽

Vol 50 (04) ◽

pp. 848-851 ◽

Cited By ~ 11

Author(s):

Marjorie B Zucker ◽

David Varon ◽

Nicholas C Masiello ◽

Simon Karpatkin

Keyword(s):

Density Gradient ◽

Combining Ability ◽

Density Gradient Centrifugation ◽

Gradient Centrifugation ◽

Electrophoretic Pattern ◽

Sucrose Density Gradient ◽

Irreversible Loss ◽

Sucrose Density Gradient Centrifugation ◽

Crossed Immunoelectrophoresis ◽

Triton X

SummaryPlatelets deprived of calcium and incubated at 37° C for 10 min lose their ability to bind fibrinogen or aggregate with ADP when adequate concentrations of calcium are restored. Since the calcium complex of glycoproteins (GP) IIb and IIIa is the presumed receptor for fibrinogen, it seemed appropriate to examine the behavior of these glycoproteins in incubated non-aggregable platelets. No differences were noted in the electrophoretic pattern of nonaggregable EDTA-treated and aggregable control CaEDTA-treated platelets when SDS gels of Triton X- 114 fractions were stained with silver. GP IIb and IIIa were extracted from either nonaggregable EDTA-treated platelets or aggregable control platelets with calcium-Tris-Triton buffer and subjected to sucrose density gradient centrifugation or crossed immunoelectrophoresis. With both types of platelets, these glycoproteins formed a complex in the presence of calcium. If the glycoproteins were extracted with EDTA-Tris-Triton buffer, or if Triton-solubilized platelet membranes were incubated with EGTA at 37° C for 30 min, GP IIb and IIIa were unable to form a complex in the presence of calcium. We conclude that inability of extracted GP IIb and IIIa to combine in the presence of calcium is not responsible for the irreversible loss of aggregability that occurs when whole platelets are incubated with EDTA at 37° C.

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