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Education ?

Medical School Score Rankings
East Carolina University (2001) *
Top 50%
* This information was reported to Vitals by the doctor or doctor's office.

Awards & Distinctions ?

Merck Manual Award for Academic Excellence
Excellence in Medical Student Teaching Award
Excellence in Medical Student Teaching Award (2005)
Merck Manual Award for Academic Excellence (2000)
Super Doctors in Texas - Rising Star
Excellence in Medical Student Teaching Award (2003)
Excellence in Medical Student Teaching Award (2004)
Outstanding Teaching Award (2005)
Patients' Choice 5th Anniversary Award (2012 - 2014)
Patients' Choice Award (2008 - 2014)
Compassionate Doctor Award - 5 Year Honoree (2013 - 2014)
Compassionate Doctor Recognition (2009 - 2014)
Top 10 Doctor - City (2014)
Dallas, TX
Obstetrician & Gynecologist
Top 10 Doctor - Metro Area (2014)
Dallas/Fort Worth Metroplex
Obstetrician & Gynecologist
On-Time Doctor Award (2009, 2014)
American Society for Reproductive Medicine
American Board of Obstetrics and Gynecology

Publications & Research

Dr. Beshay has contributed to 9 publications.
Title The Human Placenta Expresses Cyp17 and Generates Androgens De Novo.
Date June 2011
Journal The Journal of Clinical Endocrinology and Metabolism

The human placenta is believed to have insignificant CYP17 expression, rendering it dependent on the maternal and fetal compartments for the necessary androgenic precursors to yield the high levels of estrogens seen in pregnancy.

Title 17α-hydroxylase (cyp17) Expression and Subsequent Androstenedione Production in the Human Ovary.
Date February 2011
Journal Reproductive Sciences (thousand Oaks, Calif.)

Traditionally, in women, only the theca cells in the ovary and the zona reticularis layer of the adrenal cortex are believed to synthesize androgens. Interestingly, their neighboring cell layers, the granulosa cells and the zona glomerulosa cells, respectively, do not produce androgens. Recent literature has highlighted the role of the activator protein (AP-1) transcription factor, c-Fos, in the dynamics of this structural and functional relationship. Differential expression of c-Fos is believed to result in distinct patterns of steroidogenesis among these compartments in both the ovary and the adrenal glands. Clinically, deficient c-Fos levels have been implicated in the pathogenesis of polycystic ovary syndrome (PCOS). In this review, we discuss the pivotal role of c-Fos in controlling the expression of CYP17 and hence androgen production in various organ systems throughout the human body.

Title Molecular Mechanism for Repression of 17alpha-hydroxylase Expression and Androstenedione Production in Granulosa Cells.
Date January 2010
Journal The Journal of Clinical Endocrinology and Metabolism

According to the traditional two-cell two-gonadotropin model of follicular steroidogenesis, androgen production arises exclusively from theca cells. The granulosa cells, in turn, utilize androstenedione and testosterone, which are aromatized into estrone and estradiol, respectively. Differential expression of the activator protein-1 (AP-1) transcription factor, c-fos, has been postulated to result in distinct patterns of steroidogenesis in the theca and granulosa cell compartments. We hypothesize that c-fos functions to inhibit the production of 17alpha-hydroxylase 17,20 lyase (CYP17) in granulosa cells, thereby suppressing androgen synthesis.

Title The Mechanism for Protein Kinase C Inhibition of Androgen Production and 17alpha-hydroxylase Expression in a Theca Cell Tumor Model.
Date February 2008
Journal The Journal of Clinical Endocrinology and Metabolism

INTRODUCTION: In polycystic ovary syndrome (PCOS), there is increased formation of androgens by thecal cells. Moreover, PCOS ovaries have been shown to have decreased levels of c-fos transcription factor. We hypothesize that c-fos expression inhibits 17alpha-hydroxylase 17,20 lyase (CYP17) activity in the human ovary, and its decreased expression seen in PCOS may lead to elevated CYP17 transcription, resulting in increased androgen production. OBJECTIVE: Our objective was to define the role of the activator protein-1 transcription factors, namely c-fos, in the regulation of CYP17 expression in theca cells. METHODS: Human ovarian thecal-like tumor cells were used for all experiments. The following techniques were used: steroid quantification, mRNA extraction, microarray analysis, transfection, small interfering RNA, and immunohistochemistry. RESULTS: Stimulation of human ovarian thecal-like tumor cells with the protein kinase A pathway activator forskolin resulted in stimulation of C19 androgen production. In contrast, treatment with the protein kinase C pathway activator tetradecanoylphorbol acetate (TPA) resulted in decreased androgen production with a shift toward C21 progesterone production. TPA also led to complete inhibition of CYP17. Microarray data showed a 37-fold increase in c-fos after treatment with TPA. Transfection with steroidogenic factor 1 resulted in an increase in CYP17 promoter activity, which was significantly inhibited in the presence of c-fos. c-fos gene silencing led to an increase in CYP17 mRNA levels. Immunohistochemical staining for c-fos in ovaries demonstrated strong staining in granulosa cells, but not theca. CONCLUSIONS: The activator protein-1 transcription factor c-fos plays a role in the inhibition of CYP17 expression. The decreased levels of c-fos expression in polycystic ovaries may be responsible for increased CYP17 levels in PCOS.

Title Pituitary Tumors: Diagnosis, Management, and Implications for Reproduction.
Date October 2007
Journal Seminars in Reproductive Medicine

Pituitary tumors are the most common intracranial neoplasms. They are commonly encountered by the gynecologist during an evaluation for galactorrhea, menstrual disturbances, or infertility. Although the majority of these tumors are benign, their impact on the endocrine and nervous system can be striking. The availability of neuroimaging techniques has allowed for more rapid diagnosis, affording earlier treatment. This review is intended to describe the common pituitary tumors seen by the gynecologist, and their impact on reproduction and fertility in the female patient.

Title The Human Fetal Adrenal Gland, Corticotropin-releasing Hormone, and Parturition.
Date April 2007
Journal Seminars in Reproductive Medicine

Labor initiation is a complex process that remains to be fully elucidated. An area of active research involves the study of the different mechanisms that may lead to successful signaling for parturition. This review focuses on the fetal-derived signals that lead to the initiation of labor. These signals may also play a role in preterm labor when activated prematurely. Studying these signals may prove important in the prediction, diagnosis, and possible intervention in preterm labor.

Title Activity-dependent Change in Morphology of the Glial Tubular Lattice of the Crayfish Medial Giant Nerve Fiber.
Date August 2005
Journal Glia

An evaluation of electron micrographs of stimulated nerve fibers used to investigate the effect of action potential generation on the structure-function relationship between axons and its associated glial cells revealed that what was at first thought to be stimulation-induced damage to the glia was, in fact, limited to volume expansion and disaggregation of the glial tubular lattice. All other structures appeared well preserved and otherwise normal. Using a 4-point subjective scale for evaluation by two investigators, 50-Hz stimulation for 2 min was observed to cause a volume expansion and disaggregation of the tubular lattice. Quantitatively, the internal diameter of the stimulated tubular lattice increased 65% above the unstimulated control (50.96 +/- 2.09 nm and 30.81 +/- 0.87 nm, respectively, P < or = 0.001). Stimulation had its greatest effect on tubular lattice volume and organization in the adaxonal glial layer and a decreasing effect as distance from the giant axon increased. These effects are reversible since the tubular lattice diameter and degree of disaggregation preserved 10 min after the cessation of stimulation were not found to be different from their unstimulated paired controls. Axons injected with TEA, a voltage-gated potassium channel blocker, prevented stimulation-induced volume expansion and disaggregation of tubular lattice structure. These results are consistent with an active uptake of K+ with obligated water or, alternatively, hyperosmotic K+ uptake and a fixation-induced increase in water permeation. Either mechanism of K+ uptake would result in tubular lattice volume expansion and disaggregation and suggests that the tubular lattice serves a larger role than a simple trans-glial diffusion pathway.

Title Chylous Ascites: a Case of Child Abuse and an Overview of a Rare Condition.
Date October 2001
Journal Journal of Pediatric Gastroenterology and Nutrition
Title The Nucleolar Channel System Reliably Marks the Midluteal Endometrium Regardless of Fertility Status: a Fresh Look at an Old Organelle.
Journal Fertility and Sterility

OBJECTIVE: To determine whether nucleolar channel systems (NCSs) in the midluteal endometrium are associated with overall fertility status and/or with unexplained infertility. DESIGN: Retrospective and prospective clinical studies. SETTING: Repository of stored specimens from prior multicenter study and private infertility center. PATIENT(S): Retrospective study that included 97 women (49 fertile couples, 48 infertile couples) who had been randomized for endometrial biopsy during the midluteal or late luteal phase. The prospective study included 78 women with a variety of infertility diagnoses. INTERVENTION(S): Endometrial biopsies were obtained and assessed for the presence of NCSs by indirect immunofluorescence. MAIN OUTCOME MEASURE(S): The presence of NCS was graded semiquantitatively and dichotomized as normal versus low or absent. RESULT(S): Normal presence of NCS was significantly associated with the midluteal phase compared with the late luteal phase (80% vs. 29%). However, there was no association between presence of NCS and fertility status or between presence of NCS and unexplained infertility. CONCLUSION(S): Midluteal phase endometrium consistently forms NCSs regardless of fertility status, including unexplained infertility. This indicates a possible role for the NCS in initiating the window of endometrial receptivity. However, the consistent presence of NCSs across several different types of infertility challenges the likelihood that inadequate secretory transformation is a cause of infertility.

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