Description: Segment 1 Dr Ian Gilliland introduces Prof. Kellie, who works on the application of competitive binding in reproductive physiology. Kellie uses the analogy of the game 'musical chairs' to explain the assay of specific molecules by competitive binding. He continues the analogy, saying that the number of seats and guests at the party is relevant to competitive binding. Time start: 00:00:00:00 Time end: 00:04:47:22 Length: 00:04:47:22 Segment 2 Kellie continues to explain competitive binding. He talks about molecules with specific oestradiol binding sites and where they are found. He also explains radioactive oestradiol (a sex hormone) molecules and non-radioactive oestradiol molecules, which compete with each other for sites (or chairs in the game). A diagram shows the mathematical relationship. Another graph displays the same information in a different manner. He then talks about measuring plasma oestradiol levels in the follicular and luteal phases of the human menstral cycle. A similar competitive method can measure the plasma progesterone levels in the luteal phase of the cycle. Time start: 00:04:47:22 Time end: 00:09:47:00 Length: 00:04:59:03 Segment 3 Kellie discusses two problems inherent in competitive binding methods, also continuing his party game metaphor. One problem is that unless the receptor molecule is pure, non-specific binding of radioactive oestradiol will occur on other molecules. The second problem is that unless the molecule has absolute specificity, other molecules resembling oestradiol will occupy the sites. Kellie talks about the problem of a lack of absolute specificity and how to get around this when measuring oestradiol. He also speaks about the search for absolute specificity of binding and the technique of radioimmunoassay. Time start: 00:09:47:00 Time end: 00:14:44:00 Length: 00:03:57:00 Segment 4 Kellie talks about the use of steroid molecules with a molecular weight from 200-300 and how they can be used in complexes. He also says that immunological techniques that are used to measure gonadotropins or hormones are of considerable value to obstetrics. He begins to talk about how to apply the measuring techniques he has described. First, he describes the effect of the application of the determination of plasma oestradiol and progesterone during the menstral cycle. Graphs show results of samples taken from two healthy women. Time start: 00:14:44:00 Time end: 00:19:44:06 Length: 00:05:00:06 Segment 6 Prof. Kellie reports on the pregnancies in the group of women who were treated. Graphs show the pregnant women's hormone levels. He then goes on to discuss the treatment of infertile women with gonadotropins, which he says is not an entirely satisfactory method. Due to difficulties, only a limited study has been made of this method. A group study of four women was made, and he discusses the results. Time start: 00:26:20:00 Time end: 00:30:29:00 Length: 00:04:09:00. Segment 7 Kellie continues to discuss the results of the study of the four women. Graphs show the results of the study. He goes on to say that a more detailed study of the oestradiol response to human menopausal gonadotropin is needed, and that it may lead to an improvement in infertile women. Time start: 00:30:29:00 Time end: 00:35:57:00 Length: 00:05:28:00. Segment 8 Next, Kellie discusses changes in oestrogen concentration in late pregnancy. Graphs show the response by competitive protein binding of oestradiol, oestrone and oestriol in late pregnancy. He describes techniques used to separate the individual oestrogens. Time start: 00:35:57:00 Time end: 00:41:53:19 Length: 00:05:56:19. Segment 9 Diagrams show the hormone levels of a pregnant woman who delivered a baby after induced labour. A plasma sample was taken at the 40th week, and the results of this are discussed. Kellie says that there is little doubt that plasma oestrogen concentrations reflect changes more accurately than urine analyses. The lecture ends with Kellie saying that methods of competitive binding permit the presence of gonadotropins and peripheral steroid sex hormones at very low complications, and that these methods are very valuable in the fields of obstetrics and gynaecology. Time start: 00:41:53:19 Time end: 00:46:40:12 Length: 00:04:46:18