Ching Hei Yeung

Summary

Country: Germany

Publications

  1. ncbi Sodium-inorganic phosphate cotransporter NaPi-IIb in the epididymis and its potential role in male fertility studied in a transgenic mouse model
    Yaoxian Xu
    Institute of Reproductive Medicine of the University, Munster, Germany
    Biol Reprod 69:1135-41. 2003
  2. ncbi Effects of putative epididymal osmolytes on sperm volume regulation of fertile and infertile c-ros transgenic Mice
    Ching-Hei Yeung
    Institute of Reproductive Medicine of the University, Muenster, Germany
    J Androl 25:216-23. 2004
  3. ncbi Mouse models of infertility due to swollen spermatozoa
    Trevor G Cooper
    Institute of Reproductive Medicine of the University, Domagkstr 11, D 48129 Munster, Germany
    Mol Cell Endocrinol 216:55-63. 2004
  4. ncbi Relationship of cytoplasmic droplets to motility, migration in mucus, and volume regulation of human spermatozoa
    Sabina Fetic
    Institute of Reproductive Medicine, , Germany
    J Androl 27:294-301. 2006
  5. ncbi Responses of monkey epididymal sperm of different maturational status to second messengers mediating protein tyrosine phosphorylation, acrosome reaction, and motility
    C H Yeung
    Institute of Reproductive Medicine of the University, Munster, Germany
    Mol Reprod Dev 54:194-202. 1999
  6. ncbi Volume regulation of mature and immature spermatozoa in a primate model, and possible ion channels involved
    C H Yeung
    Institute of Reproductive Medicine of the University Clinic, Munster, Germany
    Hum Reprod 19:2587-93. 2004
  7. ncbi Increased luminal pH in the epididymis of infertile c-ros knockout mice and the expression of sodium-hydrogen exchangers and vacuolar proton pump H+-ATPase
    Ching Hei Yeung
    Institute of Reproductive Medicine, University of Munster, Domagkstrasse 11, D 48129 Munster, Germany
    Mol Reprod Dev 68:159-68. 2004
  8. ncbi Human sperm volume regulation. Response to physiological changes in osmolality, channel blockers and potential sperm osmolytes
    C H Yeung
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, D 48129 Munster, Germany
    Hum Reprod 18:1029-36. 2003
  9. ncbi Sperm volume regulation: maturational changes in fertile and infertile transgenic mice and association with kinematics and tail angulation
    Ching Hei Yeung
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, D 48129 Munster, Germany
    Biol Reprod 67:269-75. 2002
  10. ncbi Measurement of volume changes in mouse spermatozoa using an electronic sizing analyzer and a flow cytometer: validation and application to an infertile mouse model
    Ching Hei Yeung
    Institute of Reproductive Medicine of the University, Munster, Germany
    J Androl 23:522-8. 2002

Collaborators

Detail Information

Publications39

  1. ncbi Sodium-inorganic phosphate cotransporter NaPi-IIb in the epididymis and its potential role in male fertility studied in a transgenic mouse model
    Yaoxian Xu
    Institute of Reproductive Medicine of the University, Munster, Germany
    Biol Reprod 69:1135-41. 2003
    ....
  2. ncbi Effects of putative epididymal osmolytes on sperm volume regulation of fertile and infertile c-ros transgenic Mice
    Ching-Hei Yeung
    Institute of Reproductive Medicine of the University, Muenster, Germany
    J Androl 25:216-23. 2004
    ....
  3. ncbi Mouse models of infertility due to swollen spermatozoa
    Trevor G Cooper
    Institute of Reproductive Medicine of the University, Domagkstr 11, D 48129 Munster, Germany
    Mol Cell Endocrinol 216:55-63. 2004
    ..Further analysis could pinpoint genes essential for epididymal regulation of sperm volume, explain infertility and suggest modes of male contraception...
  4. ncbi Relationship of cytoplasmic droplets to motility, migration in mucus, and volume regulation of human spermatozoa
    Sabina Fetic
    Institute of Reproductive Medicine, , Germany
    J Androl 27:294-301. 2006
    ..Therefore, cytoplasmic droplets are not deleterious to sperm motility and may be related to physiological volume regulation, which may be predictive of some forms of human male infertility...
  5. ncbi Responses of monkey epididymal sperm of different maturational status to second messengers mediating protein tyrosine phosphorylation, acrosome reaction, and motility
    C H Yeung
    Institute of Reproductive Medicine of the University, Munster, Germany
    Mol Reprod Dev 54:194-202. 1999
    ..Development of signal transduction pathways is part of the epididymal maturational process...
  6. ncbi Volume regulation of mature and immature spermatozoa in a primate model, and possible ion channels involved
    C H Yeung
    Institute of Reproductive Medicine of the University Clinic, Munster, Germany
    Hum Reprod 19:2587-93. 2004
    ..Human ejaculated sperm undergo volume regulation, and swollen cells fail to penetrate mucus. Study of an infertile mouse model indicates maturation of volume regulation mechanism in the epididymis...
  7. ncbi Increased luminal pH in the epididymis of infertile c-ros knockout mice and the expression of sodium-hydrogen exchangers and vacuolar proton pump H+-ATPase
    Ching Hei Yeung
    Institute of Reproductive Medicine, University of Munster, Domagkstrasse 11, D 48129 Munster, Germany
    Mol Reprod Dev 68:159-68. 2004
    ..The increase in luminal fluid pH in the KO mice could also be contributed to by other epithelial regulating factors including the Na(+)-dependent glutamate transporter EAAC1 formerly reported to be down regulated in the KO...
  8. ncbi Human sperm volume regulation. Response to physiological changes in osmolality, channel blockers and potential sperm osmolytes
    C H Yeung
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, D 48129 Munster, Germany
    Hum Reprod 18:1029-36. 2003
    ..Volume regulation is an important sperm function because defective sperm cannot negotiate the female tract in an infertile mouse model and swollen human sperm cannot penetrate and migrate through mucus...
  9. ncbi Sperm volume regulation: maturational changes in fertile and infertile transgenic mice and association with kinematics and tail angulation
    Ching Hei Yeung
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, D 48129 Munster, Germany
    Biol Reprod 67:269-75. 2002
    ....
  10. ncbi Measurement of volume changes in mouse spermatozoa using an electronic sizing analyzer and a flow cytometer: validation and application to an infertile mouse model
    Ching Hei Yeung
    Institute of Reproductive Medicine of the University, Munster, Germany
    J Androl 23:522-8. 2002
    ..Laser scatter analysis of viable murine sperm by flow cytometry offers a convenient and sensitive method for the study of sperm volume regulation...
  11. ncbi Infertile spermatozoa of c-ros tyrosine kinase receptor knockout mice show flagellar angulation and maturational defects in cell volume regulatory mechanisms
    C H Yeung
    Institute of Reproductive Medicine of the University, D 48129 Munster, Germany Max Delbrück Center of Molecular Medicine, D 13122 Berlin, Germany
    Biol Reprod 61:1062-9. 1999
    ..The resultant flagellar angulation may account for the reduction in sperm numbers in the oviduct of mated females and the failure to fertilize in vivo...
  12. ncbi Effects of the ion-channel blocker quinine on human sperm volume, kinematics and mucus penetration, and the involvement of potassium channels
    C H Yeung
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, D 48129 Munster, Germany
    Mol Hum Reprod 7:819-28. 2001
    ..These channels could be targets for contraception...
  13. ncbi Changes of the major sperm maturation-associated epididymal protein HE5 (CD52) on human ejaculated spermatozoa during incubation
    C H Yeung
    Institute of Reproductive Medicine of the University, Munster, Germany
    Mol Hum Reprod 7:617-24. 2001
    ..These results suggest that during incubation in capacitating conditions, there is an opening up of the HE5 glycoprotein molecule, increasing accessibility of some sialic acid residues and of the core peptide, particularly the GPI anchor...
  14. ncbi The cause of infertility of male c-ros tyrosine kinase receptor knockout mice
    C H Yeung
    Institute of Reproductive Medicine of the University D 48129 Münster, Germany
    Biol Reprod 63:612-8. 2000
    ..The infertility of c-ros knockout male mice can be explained by the sperm's inability to enter the oviduct, as a result of their bent tails forming the entangled sperm mass and their compromised flagellar vigor within the uterus...
  15. ncbi Maturational changes of the CD52-like epididymal glycoprotein on cynomolgus monkey sperm and their apparent reversal in capacitation conditions
    C H Yeung
    Institute of Reproductive Medicine of the University, Munster, Germany
    Mol Reprod Dev 57:280-9. 2000
    ..In conclusion, the monkey epididymal secreted CD52 on sperm underwent changes in antigenic characteristics during sperm maturation which were reversed under capacitation conditions...
  16. ncbi Lack of glutamate transporter EAAC1 in the epididymis of infertile c-ros receptor tyrosine-kinase deficient mice
    Andrea Wagenfeld
    Institute of Reproductive Medicine of the University, D 48129 Munster, Germany
    J Androl 23:772-82. 2002
    ....
  17. ncbi Acquisition of volume regulatory response of sperm upon maturation in the epididymis and the role of the cytoplasmic droplet
    Trevor G Cooper
    Institute of Reproductive Medicine of the University, Munster, Germany
    Microsc Res Tech 61:28-38. 2003
    ..These osmolytes are subsequently used for regulatory volume decrease after ejaculation into the relatively hypotonic female tract. Study of the mechanisms of sperm volume regulation may highlight new contraceptive leads...
  18. ncbi Gene and protein expression in the epididymis of infertile c-ros receptor tyrosine kinase-deficient mice
    Trevor G Cooper
    Institute of Reproductive Medicine of the University, D 48129 Munster, Germany
    Biol Reprod 69:1750-62. 2003
    ..The changes in these genes could affect sperm function by modifying the composition of epididymal fluid and explain the infertility of the KO males. These genes may be targets for a posttesticular contraceptive...
  19. ncbi Male congenital hypothyroid Pax8-/- mice are infertile despite adequate treatment with thyroid hormone
    Joachim Wistuba
    Institute of Reproductive Medicine of the University, Domagkstr 11, 48149 Munster, Germany
    J Endocrinol 192:99-109. 2007
    ..It remains to be elucidated whether congenital hypothyroid male patients with mutations in the Pax8 gene are similarly affected...
  20. ncbi Aquaporin isoforms involved in physiological volume regulation of murine spermatozoa
    Ching Hei Yeung
    Centre of Reproductive Medicine and Andrology, University of Munster, D 48129 Munster, Germany
    Biol Reprod 80:350-7. 2009
    ..Therefore, the Hg(2+)-sensitive AQP8, which was localized in elongated spermatids and spermatozoa, is a likely candidate for a water channel responsible for physiological sperm volume regulation crucial to in vivo fertilization...
  21. ncbi The role of anion channels and Ca2+ in addition to K+ channels in the physiological volume regulation of murine spermatozoa
    Ching Hei Yeung
    Institute of Reproductive Medicine of the University Clinic, Munster, Germany
    Mol Reprod Dev 71:368-79. 2005
    ..These findings implicate the involvement of some unidentified VSOAC in sperm volume regulation, which is probably Ca+-dependent...
  22. ncbi Cytoplasmic droplets are normal structures of human sperm but are not well preserved by routine procedures for assessing sperm morphology
    Trevor G Cooper
    Institute of Reproductive Medicine of the University Clinic, Domagkstrasse 11, D 48129 Munster, Germany
    Hum Reprod 19:2283-8. 2004
    ..Most clinicians consider their presence on sperm to be indicative of abnormal sperm, whereas basic scientists consider them to be attributes of normal sperm...
  23. ncbi Minutes of the 14th European workshop on molecular and cellular endocrinology of the testis
    Jorg Gromoll
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, D 48129 Munster, Germany
    Mol Cell Endocrinol 257:1-5. 2006
  24. ncbi Changes in osmolality during liquefaction of human semen
    Trevor G Cooper
    Institute of Reproductive Medicine of the University Clinic, Munster, Domagkstrasse 11, D 48129 Munster, Germany
    Int J Androl 28:58-60. 2005
    ..Thus when sperm are routinely examined after liquefaction they have been subjected to osmotic stresses that are not experienced by spermatozoa entering the female tract at coitus...
  25. ncbi Computer-aided evaluation of assessment of "grade a" spermatozoa by experienced technicians
    Trevor G Cooper
    Institute of Reproductive Medicine, University of Münster Münster, Germany
    Fertil Steril 85:220-4. 2006
    ..To determine how well technicians assess progressively motile spermatozoa...
  26. ncbi Multistep and single-step treatment of human spermatozoa with cryoprotectants
    Dyah Widiasih
    Institute of Reproductive Medicine of the University, Domagkstrasse 11, Munster, Germany
    Fertil Steril 92:382-9. 2009
    ..To compare the impact of multi- and single-step addition of cryoprotectants on human spermatozoa...
  27. ncbi Vitamin K requirement and reproduction in bromadiolone-resistant Norway rats
    Jens Jacob
    Julius Kühn Institute, Federal Research Centre for Cultivated Plants, Institute for Plant Protection in Horticulture and Forestry, Vertebrate Research, Munster, Germany
    Pest Manag Sci 68:378-85. 2012
    ..The vitamin K requirement and reproductive parameters of bromadiolone-resistant rats (Westphalian resistant strain; VKOR variant Tyr139Cys) and bromadiolone-susceptible Norway rats were compared...
  28. ncbi Why are epididymal tumours so rare?
    Ching Hei Yeung
    Shandong Stem Cell Engineering and Technology Research Centre, Yuhuangding Hospital, Yantai, China
    Asian J Androl 14:465-75. 2012
    ..Understanding these mechanisms may throw light on cancer prevention and therapy in general...
  29. ncbi New horizons for in vitro spermatogenesis? An update on novel three-dimensional culture systems as tools for meiotic and post-meiotic differentiation of testicular germ cells
    Jan Bernd Stukenborg
    Institute of Reproductive and Regenerative Biology of the Centre of Reproductive Medicine and Andrology, University Munster, Domagkstrasse 11 48129, Munster, Germany
    Mol Hum Reprod 15:521-9. 2009
    ..Further research efforts are required to reveal the applicability of this culture technique for human germ cells and the functionality of the spermatozoa for generating offspring...
  30. ncbi Norethisterone enanthate has neither a direct effect on the testis nor on the epididymis: a study in adult male cynomolgus monkeys (Macaca fascicularis)
    Aris Junaidi
    Institute of Reproductive Medicine of the University, , Germany
    Eur J Endocrinol 152:655-61. 2005
    ..CONCLUSIONS: Short-term NETE treatment has neither a direct effect on the testis nor on the epididymis in this nonhuman primate model and its contraceptive effects appear to be exerted exclusively through gonadotropin suppression...
  31. ncbi Rebuttal of a role for the epididymis in sperm quality control by phagocytosis of defective sperm
    Trevor G Cooper
    J Cell Sci 115:5-7. 2002
  32. ncbi Epididymal dysfunction initiated by the expression of simian virus 40 T-antigen leads to angulated sperm flagella and infertility in transgenic mice
    Petra Sipila
    Department of Physiology, Institute of Biomedicine, University of Turku, FIN 20520 Turku, Finland
    Mol Endocrinol 16:2603-17. 2002
    ..This novel mouse line provides a model for epididymal dysfunction leading to defects in posttesticular sperm maturation and infertility...
  33. ncbi Essential role of the apolipoprotein E receptor-2 in sperm development
    Olav M Andersen
    Max Delbrueck Center for Molecular Medicine and Medical Faculty of the Free University, D 13125 Berlin, Germany
    J Biol Chem 278:23989-95. 2003
    ....
  34. ncbi Concentrations of carnitine, glutamate and myo-inositol in epididymal fluid and spermatozoa from boars
    Anna Pruneda
    Biotechnology of Porcine Reproduction, Department of Biology INTEA, Faculty of Sciences, University of Girona, Campus Montilivi s n, 17071 Girona, Spain
    Anim Reprod Sci 97:344-55. 2007
    ..This is the first attempt to elucidate the changes in the content of glutamate and inositol in epididymal spermatozoa of mammals and in the fluid from different epididymal regions of boars...
  35. ncbi Changes in endocrine profile and reproductive organs during puberty in the male marmoset monkey (Callithrix jacchus)
    Ramesh K Chandolia
    Institute for Reproductive Medicine of the University, Domagkstr 11, D-48129 Muenster, Germany
    Reproduction 132:355-63. 2006
    ....
  36. ncbi Localization and characterization of an orphan receptor, guanylyl cyclase-G, in mouse testis and sperm
    Yen Hua Huang
    Department of Biochemistry and Graduate Institute of Medical Sciences, School of Medicine, Taipei Medical University, Taipei 110, Taiwan
    Endocrinology 147:4792-800. 2006
    ..Together, these results indicate that mGC-G is proteolytically modified in mature sperm membrane and suggest that mGC-G-mediated signaling may play a critical role in gamete/reproductive biology...
  37. ncbi Antimicrobial drug ornidazole inhibits hamster sperm capacitation, in vitro
    Archana B Siva
    Centre for Cellular and Molecular Biology (CCMB, Uppal Road, Hyderabad, India
    Reprod Toxicol 22:702-9. 2006
    ..5 h) of the drug to the spermatozoa...
  38. ncbi Study of the polyol pathway in the porcine epididymis
    Anna Pruneda
    Biotechnology of Porcine Reproduction, Department of Biology INTEA, Faculty of Sciences, University of Girona, Girona, Spain
    Mol Reprod Dev 73:859-65. 2006
    ..Sperm metabolism of glucose and fructose may explain their lower concentrations in the cauda and sorbitol could be a metabolic substrate or osmolyte required for volume regulation...
  39. ncbi Hamster contraception associated protein 1 (CAP1)
    Archana B Siva
    Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
    Mol Reprod Dev 68:373-83. 2004
    ....