Experts and Doctors on spermatozoa in Honolulu, Hawaii, United States
Locale: Honolulu, Hawaii, United States
- Suganuma R, Yanagimachi R, Meistrich M. Decline in fertility of mouse sperm with abnormal chromatin during epididymal passage as revealed by ICSI. Hum Reprod. 2005;20:3101-8 pubmed..The advantage of using caput epididymal sperm for ICSI in certain situations may be considered as an approach to be tested in human assisted reproduction. ..
- Shaman J, Prisztoka R, Ward W. Topoisomerase IIB and an extracellular nuclease interact to digest sperm DNA in an apoptotic-like manner. Biol Reprod. 2006;75:741-8 pubmed..They also show that the unique chromatin structure of spermatozoa may provide an important model to study the regulated degradation of chromatin by TOP2B and associated nucleases. ..
- Gawecka J, Marh J, Ortega M, Yamauchi Y, Ward M, Ward W. Mouse zygotes respond to severe sperm DNA damage by delaying paternal DNA replication and embryonic development. PLoS ONE. 2013;8:e56385 pubmed publisher..Our data demonstrate that the zygote responds to sperm DNA damage through a non-apoptotic mechanism that acts by slowing paternal DNA replication and ultimately leads to arrest in embryonic development. ..
- Akutsu H, Tres L, Tateno H, Yanagimachi R, Kierszenbaum A. Offspring from normal mouse oocytes injected with sperm heads from the azh/azh mouse display more severe sperm tail abnormalities than the original mutant. Biol Reprod. 2001;64:249-56 pubmed..Furthermore, our findings stress the risk of enhancing a phenotypic abnormality caused by mutant male genotypes introduced through bypassing the biologic mechanisms of natural sperm selection during fertilization. ..
- Kaneko T, Whittingham D, Overstreet J, Yanagimachi R. Tolerance of the mouse sperm nuclei to freeze-drying depends on their disulfide status. Biol Reprod. 2003;69:1859-62 pubmed..The potential for freeze-drying damage seems likely to relate to the -SS- status of sperm proteins, in particular its protamines...
- Ajduk A, Yamauchi Y, Ward M. Sperm chromatin remodeling after intracytoplasmic sperm injection differs from that of in vitro fertilization. Biol Reprod. 2006;75:442-51 pubmed..Our data have significance for the refinement of the molecular and biologic mechanisms associated with ICSI for current and future applications...
- Yamauchi Y, Ward M. Preservation of ejaculated mouse spermatozoa from fertile C57BL/6 and infertile Hook1/Hook1 mice collected from the uteri of mated females. Biol Reprod. 2007;76:1002-8 pubmed..The method is applicable for all types of mice, including those with male infertility syndromes. The sole requirement is that the male of interest is able to copulate and its ejaculate contains spermatozoa. ..
- Yamauchi Y, Ajduk A, Riel J, Ward M. Ejaculated and epididymal mouse spermatozoa are different in their susceptibility to nuclease-dependent DNA damage and in their nuclease activity. Biol Reprod. 2007;77:636-47 pubmed..This nuclease activity was detected both in the sperm-free fraction of preparations and isolated sperm...
- Yamauchi Y, Doe B, Ajduk A, Ward M. Genomic DNA damage in mouse transgenesis. Biol Reprod. 2007;77:803-12 pubmed..The present study demonstrates that DNA damage occurs after both the microinjection of pronuclei and ICSI-mediated transgenesis, albeit through different mechanisms...
- Yamauchi Y, Riel J, Ward M. Paternal DNA damage resulting from various sperm treatments persists after fertilization and is similar before and after DNA replication. J Androl. 2012;33:229-38 pubmed publisher..This process, however, was independent of DNA synthesis and took place during oocyte maturation...
- Ward W. Isolation of sperm nuclei and nuclear matrices from the mouse, and other rodents. Methods Mol Biol. 2013;927:437-44 pubmed..Two methods are described for the isolation of rodent sperm nuclei using sucrose step gradients in which the sperm nuclei are only centrifuged one time, minimizing potential damage by mechanical stress...