User:Z3330986

Lab Attendance

Lab 1 --Z3330986 11:49, 25 July 2012 (EST)

Lab 2 --Z3330986 10:25, 1 August 2012

Lab 3 --Z3330986 10:33, 8 August 2012 (EST)

Individual Assessment

Lab 1

1. As with many medical terms, in vitro is derived from Latin, translating to "in glass." It is so named, as early experiments involving tissue cultures outside of the specimen (as opposed to in vivo, inside the body) were undertaken in glass containers. In Vitro Fertilization was developed by Robert G. Edwards. He was awarded the Nobel prize in 2010 in the field of medicine and physiology for his work. A link to the Nobel prize web page can be found here:[[1]]

2.Sperm counts and sperm sex ratio in male infertility patients[[2]]

In this study, the sex chromosomes and sperm count of infertile men were analysed in order to determine whether infertility plays a role in the determination offspring gender. Infertility is a fairly arbitrary categorization though for the purposes for this experiment, it was taken to mean couples who had greater than or equal to two recurrent pregnancy losses or two failed IVF treatments. The subsequent results found that in men with a low sperm concentration, semen volume and total motile sperm count, there was a significantly lower proprortion of the Y-bearing sperm. Thus there is a direct link between spermatogenesis and sex ratio.

The precise mechanisms for a diminished Y-bearing proportion of sperm is unclear. It is suggested that perhaps societal stresses or individual wants and needs may play a role in the genetic makeup of sperm. Biologically, it is reasoned that an infertile man will produce less male heirs so as to minimise the chance that his offspring may encounter the same problems.

Lab 2

In order for successful implantation to occur, estrogen controlled proliferation of the uterine epitheium must be attneuated by the hormone progesterone. Previously the mechanisms of attenuation were not well understood however recent study has shown the helix-loop-helix protein, Hand2, plays an integral role in suppressing estrogen-driven growth of uterine epithelium. It does this by stopping the induction of Fibroblast growth factors (FGF) which are responsible for maintaining estrogen mediated growth of the epithelium. [1]

From a clinical perspective it may also direct research to improve treatments which target over-proliferative disorders such as endometriosis and endometrial cancer. Particularly endometriosis, which currently resists progesterone targeted medications.

Reference

1. The Antiproliferative Action of Progesterone in Uterine Epithelium Is Mediated by Hand2 Quanxi Li, Athilakshmi Kannan, Francesco J. DeMayo, John P. Lydon, Paul S. Cooke, Hiroyuki Yamagishi, Deepak Srivastava, Milan K. Bagchi, and Indrani C. Bagchi Science 18 February 2011: 331 (6019), 912-916. [DOI:10.1126/science.1197454]