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Styer, Aaron

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Styer

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Aaron

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Styer, Aaron

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Now showing 1 - 5 of 5
  • Publication

    Metformin Therapy in a Hyperandrogenic Anovulatory Mutant Murine Model with Polycystic Ovarian Syndrome Characteristics Improves Oocyte Maturity during Superovulation

    (BioMed Central, 2011) Sabatini, Mary; Guo, Lankai; Lynch, M. J.; Doyle, Joseph O'Brien; Lee, HoJoon; Rueda, Bo; Styer, Aaron

    Background: Metformin, an oral biguanide traditionally used for the treatment of type 2 diabetes, is widely used for the management of polycystic ovary syndrome (PCOS)-related anovulation. Because of the significant prevalence of insulin resistance and glucose intolerance in PCOS patients, and their putative role in ovulatory dysfunction, the use of metformin was touted as a means to improve ovulatory function and reproductive outcomes in PCOS patients. To date, there has been inconsistent evidence to demonstrate a favorable effect of metformin on oocyte quality and competence in women with PCOS. Given the heterogeneous nature of this disorder, we hypothesized that metformin may be beneficial in mice with aberrant metabolic characteristics similar to a significant number of PCOS patients. The aim of this study was to gain insight into the in vitro and in vivo effects of metformin on oocyte development and ovulatory function. Methods: We utilized metformin treatment in the transgenic ob/ob and db/db mutant murine models which demonstrate metabolic and reproductive characteristics similar to women with PCOS. Results: Metformin did not improve in vitro oocyte maturation nor did it have an appreciable effect on in vitro granulosa cell luteinization (progesterone production) in any genotype studied. Although both mutant strains have evidence of hyperandrogenemia, anovulation, and hyperinsulinemia, only db/db mice treated with metformin had a greater number of mature oocytes and total overall oocytes compared to control. There was no observed impact on body mass, or serum glucose and androgens in any genotype. Conclusions: Our data provide evidence to suggest that metformin may optimize ovulatory performance in mice with a specific reproductive and metabolic phenotype shared by women with PCOS. The only obvious difference between the mutant murine models is that the db/db mice have elevated leptin levels raising the questions of whether their response to metformin is related to elevated leptin levels and/or if a subset of PCOS women with hyperleptinemia may be responsive to metformin therapy. Further study is needed to better define a subset of women with PCOS that may be responsive to metformin.

  • Publication

    Clinical Characteristics Associated with Antibiotic Treatment Failure for Tuboovarian Abscesses

    (Hindawi Publishing Corporation, 2016) Farid, Huma; Lau, Trevin; Karmon, Anatte E.; Styer, Aaron

    Objective:. Although parenteral antibiotic treatment is a standard approach for tuboovarian abscesses, a significant proportion of patients fail therapy and require interventional radiology (IR) guided drainage. The objective of this study is to assess if specific clinical factors are associated with antibiotic treatment failure. Study Design. Retrospective medical record review of patients hospitalized for tuboovarian abscesses from 2001 through 2012 was performed. Clinical characteristics were compared for patients who underwent successful parenteral antibiotic treatment, failed antibiotic treatment necessitating subsequent IR drainage, initial drainage with concurrent antibiotics, and surgery. Results. One hundred thirteen patients admitted for inpatient treatment were identified. Sixty-one (54%) patients were treated with antibiotics alone. Within this group, 24.6% failed antibiotic treatment and required drainage. Mean white blood cell count (K/μL) (18.7 ± 5.94 versus 13.9 ± 5.12) (p = 0.003), mean maximum diameter of tuboovarian abscess (cm) (6.8 ± 2.9 versus 5.2 ± 2.0) (p = 0.03), and length of stay (days) (9.47 ± 7.43 versus 4.59 ± 2.4) (p = 0.002) were significantly greater for patients who failed antibiotic treatment. Conclusions. Admission white blood cell count greater than 16 K/μL and abscess size greater than 5.18 cm are associated with antibiotic treatment failure. These factors may provide guidance for initial selection of IR guided drainage.

  • Publication

    MicroRNA-15b regulates reversion-inducing cysteine-rich protein with Kazal motifs (RECK) expression in human uterine leiomyoma

    (BioMed Central, 2016) Guan, Yichun; Guo, Lankai; Zukerberg, Lawrence; Rueda, Bo; Styer, Aaron

    Background: Human uterine leiomyoma (fibroids; LYO) are the most common benign neoplasms in reproductive-aged women. Dysregulated extracellular matrix and irregular LYO reversion-inducing cysteine-rich protein with Kazal motifs (RECK) expression are thought to be mediated by aberrant microRNA (miR) expression. The relationship of miR-15b and RECK expression in LYO has not been studied. Methods: The expression levels of miR-15b and RECK were determined by quantitative RT-PCR, Western blot, and immunohistochemistry in cultures derived from commercial primary leiomyoma (cpLYO) and myometrial (cpMYO) cell lines and leiomyoma (pLYO) and myometrium (pMYO) tissue from surgical samples respectively. The relationship between miR-15b and RECK expression in cpLYO and pLYO (compared to their respective myometrial controls) was evaluated following transfection of cell cultures with either miR-15b mimic or inhibitor. Results: Elevated levels of miR-15b were observed in cpLYO (2.82-fold; p = 0.04) and pLYO cell (1.30-fold; p = 0.0001) cultures respectively compared to corresponding MYO cell controls. Following transfection with miR-15b mimic, cpLYO cells (0.62-fold; p < 0.0001) and pLYO cells (0.68-fold; p < 0.0001) demonstrated reduced RECK protein expression. Following transfection with miR-15b inhibitor, cpLYO cells (1.20-fold; p < 0.0001) and pLYO cells (1.31-fold; p = 0.0007) demonstrated elevated RECK protein expression. RECK protein expression was reduced in pLYO tissues (0.73-fold; p < 0.0001) and pLYO (0.47-fold; p = 0.047) cells when compared to the corresponding MYO tissue controls. Conclusion: Our findings suggest that miR-15b negatively regulates RECK expression in LYO, and increased miR-15b and decreased RECK expression may contribute to the pathobiology of LYO. The functional significance of miR-15b and RECK expression warrants further investigation as potential therapeutic targets for the treatment of human LYO.

  • Publication

    Elective single embryo transfer- the power of one

    (BioMed Central, 2016) Lee, Amy M.; Connell, Matthew T.; Csokmay, John M.; Styer, Aaron

    Despite the highest historical live birth success rates for couples undergoing in vitro fertilization (IVF), there has been an epidemic of iatrogenic twin and higher order gestation conceived from this treatment. Continued improvement in cryopreservation techniques have allowed preservation of supernumerary embryos for use in future cycles, and refinements in culture systems and embryo selection have resulted in the transfer of fewer embryos while maintaining favorable pregnancy rates. The voluntary transfer of a single high quality embryo, elective single embryo transfer (eSET), has significantly reduced multiple gestation rates and maximized the rate of singleton pregnancy without compromising overall success rates. Although eSET is the standard of care in several developed countries, utilization in the United States has been slow. States with mandated IVF insurance have seen decreases in preterm birth rates yielding down stream health care savings. Herein, the evolution and future applications of this practice to reduce the risk of iatrogenic twins is reviewed.

  • Publication

    MicroRNA 21a-5p overexpression impacts mediators of extracellular matrix formation in uterine leiomyoma

    (BioMed Central, 2018) Cardozo, Eden R.; Foster, Rosemary; Karmon, Anatte E.; Lee, Amy E.; Gatune, Leah W.; Rueda, Bo; Styer, Aaron

    Background: MicroRNAs (MiR) may promote fibroid development via altered expression of genes involved in cell proliferation and ECM formation, and evidence supports aberrant expression of MicroRNA (MiR) 21a-5p in fibroids. The purpose of this study was to investigate the functional significance of MiR 21a-5p overexpression in the pathobiology of leiomyomata (fibroids). Methods: A basic science experimental design using immortalized fibroid and myometrial cell lines derived from patient-matched specimens was used. Stable overexpression of MiR-21a-5p in an immortalized fibroid and patient matched myometrial cell line was achieved through lentiviral vector infection. Main outcome measures were MiR-21-5p overexpression, target gene and protein expression, collagen (COL1A1) production, cell proliferation, cell migration, and cell cycle stages of fibroid and myometrial immortalized cell lines. Results: MiR-21a-5p was overexpressed to similar levels in fibroid and myometrial cell lines after lentiviral infection. Increased expression of miR-21 resulted in increased gene and protein expression of TGF-β3 in both fibroid and myometrial cells. Changes in expression of the ECM genes Fibronectin, Collagen 1A1, CTGF, Versican and DPT were seen in both fibroid and myometrial cells. Changes were also seen in Matrix Metalloproteinase (MMP) related genes including MMP 2, MMP 9, MMP 11 and Serpine 1 in both fibroid and myometrial cells. MiR-21 upregulation resulted in increased proliferation and migration in fibroid cells compared to myometrial cells. Conclusions: MiR-21a-5p overexpression results in changes in the expression of ECM mediators in both fibroid and myometrial cells, and increased cell proliferation in fibroid cells. These finding suggest a potential functional role of MiR-21a-5p in the development of uterine fibroids and warrant further investigation. Electronic supplementary material The online version of this article (10.1186/s12958-018-0364-8) contains supplementary material, which is available to authorized users.