William S. Evans, MD
Graduate School: University of Virginia
Primary Appointment: Professor, Medicine, Endocrinology and Metabolism
Reproductive endocrinology, polycystic ovary syndrome, biomathematical modeling of the hypothalamic-pituitary-ovarian axis.
Email Address: email@example.com
Dr. William S. Evans' clinical research program is focused on elucidating the function(s) of the hypothalamic, pituitary and ovarian components of the female reproductive axis. Biomathematical modeling techniques are used to define and quantitate hormone secretion by the GnRH neuronal system within the hypothalamus; by the gonadotropes within the anterior pituitary gland which secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH); and by the theca and granulosa cells within the ovary which secrete a number of gonadal hormones in response to LH and FSH stimulation. Other biomathematical techniques are used to define both feedforward and feedback effects of such reproductive hormone in terms of the overall reproductive axis network. The primary objective of these studies is to gain a better understanding of how these systems perform under physiological circumstances—including those associated with normal aging and the menopausal transition—and within pathophysiological circumstances which may result in menstrual dysfunction, infertility and miscarriage such as is seen in the polycystic ovary syndrome.
Johnson ML, Veldhuis PP, Grimmichova T, Farhy LS, Evans WS. Validation of a deconvolution procedure (AutoDecon) for identification and characterization of fasting insulin secretory bursts. J Diabetes Sci Technol. 2010 Sep 1;4(5):1205-13. PubMed PMID: 20920442; PubMed Central PMCID: PMC2956805.
Johnson ML, Veldhuis PP, Evans WS. Signal-response modeling of partial hormone feedback networks. J Diabetes Sci Technol. 2009 Jan;3(1):34-43. PubMed PMID: 20046649; PubMed Central PMCID: PMC2662613.
Johnson ML, Pipes L, Veldhuis PP, Farhy LS, Nass R, Thorner MO, Evans WS. AutoDecon: a robust numerical method for the quantification of pulsatile events. Methods Enzymol. 2009;454:367-404. doi: 10.1016/S0076-6879(08)03815-9. PubMed PMID: 19216935; PubMed Central PMCID: PMC2662594.
Evans WS, Farhy LS, Johnson ML. Biomathematical modeling of pulsatile hormone secretion: a historical perspective. Methods Enzymol. 2009;454:345-66. doi: 10.1016/S0076-6879(08)03814-7. PubMed PMID: 19216934; PubMed Central PMCID: PMC2662597.
Johnson ML, Pipes L, Veldhuis PP, Farhy LS, Boyd DG, Evans WS. AutoDecon, a deconvolution algorithm for identification and characterization of luteinizing hormone secretory bursts: description and validation using synthetic data. Anal Biochem. 2008 Oct 1;381(1):8-17. doi: 10.1016/j.ab.2008.07.001. Epub 2008 Jul 4. PubMed PMID: 18639514; PubMed Central PMCID: PMC2557553.
Iuorno MJ, Islam LZ, Veldhuis PP, Boyd DG, Farhy LS, Johnson ML, Nestler JE, Evans WS. Leptin secretory burst mass correlates with body mass index and insulin in normal women but not in women with polycystic ovary syndrome. Metabolism. 2007 Nov;56(11):1561-5. PubMed PMID: 17950108.
Evans WS, Taylor AE, Boyd DG, Johnson ML, Matt DW, Jimenez Y, Nestler JE. Lack of effect of short-term diazoxide administration on luteinizing hormone secretion in women with polycystic ovary syndrome. Fertil Steril. 2007 Jul;88(1):118-24. Epub 2007 Feb 6. PubMed PMID: 17289040.
Quigg M, Kiely JM, Johnson ML, Straume M, Bertram EH, Evans WS. Interictal and postictal circadian and ultradian luteinizing hormone secretion in men with temporal lobe epilepsy. Epilepsia. 2006 Sep;47(9):1452-9. PubMed PMID: 16981860.
Weltman A, Weltman JY, Roy CP, Wideman L, Patrie J, Evans WS, Veldhuis JD. Growth hormone response to graded exercise intensities is attenuated and the gender difference abolished in older adults. J Appl Physiol. 2006 May;100(5):1623-9. Epub 2005 Dec 29. PubMed PMID: 16384836.
Irving BA, Patrie JT, Anderson SM, Watson-Winfield DD, Frick KI, Evans WS, Veldhuis JD, Weltman A. The effects of time following acute growth hormone administration on metabolic and power output measures during acute exercise. J Clin Endocrinol Metab. 2004 Sep;89(9):4298-305. Epub 2004 Aug 24. PubMed PMID:15328062.