Background： The purpose of this study was to determine the association of three proteins involved in sperm function on the freezability of porcine semen： the heat shock protein 90 alpha（HSP90a）, the Niemann-Pick d...Background： The purpose of this study was to determine the association of three proteins involved in sperm function on the freezability of porcine semen： the heat shock protein 90 alpha（HSP90a）, the Niemann-Pick disease type C2 protein（NPC2）, and lipocalin-type prostaglandin D synthase（L-PGDS）.Six adult boars（each boar was ejaculated three times, 18 in total） were classified by freezability based on the percentage of functionally competent sperm. The male semen with highest freezability（MHF） and the male semen with lowest freezability（MLF） were centrifuged immediately after collection to separate seminal plasma and spermatozoa to make four possible combinations of these two components and to incubate them for 3 h,adjusting the temperature to 17 °C, to freeze them afterwards. The quantification of proteins was performed in two stages： at zero and at 3 h after incubation of the four combinations.Results： The spermatozoa × incubation time（IT） interaction only had effect（P 〈 0.01） on HSP90 a levels; this protein increased in seminal plasma, after 3 h of incubation, in larger quantity（P 〈 0.05） in combinations with MLF spermatozoa. In relation with the NPC2 protein, two isoforms of 16 and 19 kDa were identified. The 19 kDa isoform was affected（P 〈 0.01） only by the seminal plasma × IT interaction, with superior values（P 〈 0.01） both at zero and three hours of incubation, in the combinations with MHF seminal plasma; and 16 kDa isoform was affected（P 〈 0.01） only by the IT with reduction after 3 h of incubation. The levels of L-PGDS was affected（P 〈 0.01）only by the spermatozoa × IT interaction, which reduced（P 〈 0.01） in combinations with MLF spermatozoa after 3 h of incubation.Conclusions： It is possible to consider that the three proteins evaluated were associated with freezability of boar semen due, especially, to the fact that mixtures with MLF spermatozoa showed greater increase levels of the HSP90 a protein and reduction of L-PGDS in plasma. In addition, the seminal plasma of MHF had higher concentration of the NPC2 of 19 kDa protein, which was reduced by incubating with MHF spermatozoa.展开更多
Semen cryopreservation is widely used in assisted reproductive technologies, but it reduces sperm quality dramatically. The aim of this study was to develop a model using basal semen quality to predict the outcome of ...Semen cryopreservation is widely used in assisted reproductive technologies, but it reduces sperm quality dramatically. The aim of this study was to develop a model using basal semen quality to predict the outcome of postthaw semen parameters and improve the efficiency of cryopreservation in a human sperm bank. Basal semen parameters of 180 samples were evaluated in the first stage, and a multiple logistic regression analysis involving a backward elimination selection procedure was applied to select independent predictors. After a comprehensive analysis of all results, we developed a new model to assess the freezability of sperm. Progressive motility （PR）, straight-line velocity （VSL） and average path velocity （VAP） were included in our model. A greater area under the receiver operating characteristic curve was obtained in our model when compared with other indicators. In the second stage of our study, samples that satisfied the new model were selected to undergo freeze-thawing. Compared with the first stage, the rate of good freezability was increased significantly （94% vs 67%, P = 0.003）. By determining basal semen quality, we have developed a new model to improve the efficiency of cryopreservation in a human sperm bank.展开更多
For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quan...For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quantification scheme for the freezable bound water based on the water-content dependence of glass transition temperature, by which also the concentration range for the solutions that may undergo recrystallization finds a clear definition. Furthermore, we find that depending on the amount of the freezable bound water, different temperature protocols should be devised to achieve a complete recrystallization. Our results may be helpful for understanding the dynamics of supercooled aqueous solutions and for improving their manipulation in various industries.展开更多
Cryopreservation has undergone tremendous advances and is widely used in animal production based on decades of study of cellular permeability, freezability and empirical generalization. Several improvement are particu...Cryopreservation has undergone tremendous advances and is widely used in animal production based on decades of study of cellular permeability, freezability and empirical generalization. Several improvement are particularly important: the cryopreservation protocol has been continuously re?ned over the years to achieve greater reproductive performance; cryoprotective agents are more effective and less toxic than previously; there has been signi?cant innovation in advanced cryopreservation systems and carriers. Despite this, there are still problems that urgently require practical solutions, such as remedies for cryodamage and encouraging the use of frozen–thawed porcine sperm in pig production.展开更多
Recent investigations indicated that the absorbed water in the hydrated pro- teins was in different states. A portion of molecules of the absorbed water were bound up with hydrophilic sites on the protein surface by h...Recent investigations indicated that the absorbed water in the hydrated pro- teins was in different states. A portion of molecules of the absorbed water were bound up with hydrophilic sites on the protein surface by hydrogen bonds and did not join in the ice lattice. The water in this state was called nonfreezable water. The other water was called freezable water, but still it might be in different展开更多
基金funded by the Vice-Rector’s Office at Universidad de Caldas
文摘Background： The purpose of this study was to determine the association of three proteins involved in sperm function on the freezability of porcine semen： the heat shock protein 90 alpha（HSP90a）, the Niemann-Pick disease type C2 protein（NPC2）, and lipocalin-type prostaglandin D synthase（L-PGDS）.Six adult boars（each boar was ejaculated three times, 18 in total） were classified by freezability based on the percentage of functionally competent sperm. The male semen with highest freezability（MHF） and the male semen with lowest freezability（MLF） were centrifuged immediately after collection to separate seminal plasma and spermatozoa to make four possible combinations of these two components and to incubate them for 3 h,adjusting the temperature to 17 °C, to freeze them afterwards. The quantification of proteins was performed in two stages： at zero and at 3 h after incubation of the four combinations.Results： The spermatozoa × incubation time（IT） interaction only had effect（P 〈 0.01） on HSP90 a levels; this protein increased in seminal plasma, after 3 h of incubation, in larger quantity（P 〈 0.05） in combinations with MLF spermatozoa. In relation with the NPC2 protein, two isoforms of 16 and 19 kDa were identified. The 19 kDa isoform was affected（P 〈 0.01） only by the seminal plasma × IT interaction, with superior values（P 〈 0.01） both at zero and three hours of incubation, in the combinations with MHF seminal plasma; and 16 kDa isoform was affected（P 〈 0.01） only by the IT with reduction after 3 h of incubation. The levels of L-PGDS was affected（P 〈 0.01）only by the spermatozoa × IT interaction, which reduced（P 〈 0.01） in combinations with MLF spermatozoa after 3 h of incubation.Conclusions： It is possible to consider that the three proteins evaluated were associated with freezability of boar semen due, especially, to the fact that mixtures with MLF spermatozoa showed greater increase levels of the HSP90 a protein and reduction of L-PGDS in plasma. In addition, the seminal plasma of MHF had higher concentration of the NPC2 of 19 kDa protein, which was reduced by incubating with MHF spermatozoa.
文摘Semen cryopreservation is widely used in assisted reproductive technologies, but it reduces sperm quality dramatically. The aim of this study was to develop a model using basal semen quality to predict the outcome of postthaw semen parameters and improve the efficiency of cryopreservation in a human sperm bank. Basal semen parameters of 180 samples were evaluated in the first stage, and a multiple logistic regression analysis involving a backward elimination selection procedure was applied to select independent predictors. After a comprehensive analysis of all results, we developed a new model to assess the freezability of sperm. Progressive motility （PR）, straight-line velocity （VSL） and average path velocity （VAP） were included in our model. A greater area under the receiver operating characteristic curve was obtained in our model when compared with other indicators. In the second stage of our study, samples that satisfied the new model were selected to undergo freeze-thawing. Compared with the first stage, the rate of good freezability was increased significantly （94% vs 67%, P = 0.003）. By determining basal semen quality, we have developed a new model to improve the efficiency of cryopreservation in a human sperm bank.
基金Project supported by the Knowledge Innovation Project of Chinese Academy of Sciences on Water Science Research(Grant No.KJZD-EW-M03)the National Natural Science Foundation of China(Grant Nos.11474325 and 11290161)
文摘For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quantification scheme for the freezable bound water based on the water-content dependence of glass transition temperature, by which also the concentration range for the solutions that may undergo recrystallization finds a clear definition. Furthermore, we find that depending on the amount of the freezable bound water, different temperature protocols should be devised to achieve a complete recrystallization. Our results may be helpful for understanding the dynamics of supercooled aqueous solutions and for improving their manipulation in various industries.
基金supported by National Natural Science Foundation of China(31101714)National Transgenic Creature Breeding Grand Project(2016ZX08008-003)
文摘Cryopreservation has undergone tremendous advances and is widely used in animal production based on decades of study of cellular permeability, freezability and empirical generalization. Several improvement are particularly important: the cryopreservation protocol has been continuously re?ned over the years to achieve greater reproductive performance; cryoprotective agents are more effective and less toxic than previously; there has been signi?cant innovation in advanced cryopreservation systems and carriers. Despite this, there are still problems that urgently require practical solutions, such as remedies for cryodamage and encouraging the use of frozen–thawed porcine sperm in pig production.
文摘Recent investigations indicated that the absorbed water in the hydrated pro- teins was in different states. A portion of molecules of the absorbed water were bound up with hydrophilic sites on the protein surface by hydrogen bonds and did not join in the ice lattice. The water in this state was called nonfreezable water. The other water was called freezable water, but still it might be in different
