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Featured researches published by Stan A. Beyler.


Biology of Reproduction | 2000

Blockade of the αvβ3 Integrin Adversely Affects Implantation in the Mouse

M.J. Illera; Emily Cullinan; Yaoting Gui; Lingwen Yuan; Stan A. Beyler; Bruce A. Lessey

Abstract The role of endometrial and embryonic integrins during implantation remains unresolved although work in animal models and in humans supports their involvement in this process. Temporal and spatial distribution of the αvβ3 integrin on both embryo and endometrium in women and mice coincides with the time of initial attachment during implantation. In mice, the endometrial and embryonic αvβ3 integrin is present at the time of implantation, as shown by reverse transcription-polymerase chain reaction and immunohistochemistry. In situ hybridization demonstrates the presence of the αvβ3 integrin on the subluminal stromal cells of the uterus. Functional blockade of this integrin on the day of implantation by intrauterine injection of neutralizing monoclonal antibodies against αv or β3 integrin subunits, arg-gly-asp (RGD)-containing peptides, or of the disintegrin echistatin, reduced the number of implantation sites compared to controls receiving BSA. These studies demonstrate that, like the human, the murine αvβ3 integrin is expressed at the time of implantation in the endometrium and on the blastocyst, and may play a critical role in the cascade of events leading to successful implantation.


Fertility and Sterility | 1999

Effect of exogenous gonadotropins on endometrial maturation in oocyte donors

William R. Meyer; Debra B. Novotny; Marc A. Fritz; Stan A. Beyler; Lynda Wolf; Bruce A. Lessey

OBJECTIVE To determine the effects of controlled ovarian hyperstimulation (COH) on endometrial maturation. DESIGN Prospective, before and after evaluation of midluteal endometrial biopsies in oocyte donors spontaneous and subsequent COH cycles. SETTING Tertiary academic medical center assisted reproductive technologies clinic. PATIENT(S) Nineteen oocyte donors. INTERVENTION(S) Exogenous gonadotropins, endometrial biopsies. MAIN OUTCOME MEASURE(S) Endometrial histology and an immunohistochemical marker of uterine receptivity, the alphavbeta3 vitronectin. RESULT(S) Glandular and stromal dyssynchrony was more common after COH in 16 (80%) of 20 cycles than 6 (30%) of 20 spontaneous cycles (P <.05). Glandular lag was more frequent in COH cycles and unaffected by progesterone administration. The beta3 subunit of the alphavbeta3 vitronectin receptor was present in 9 (45%) of 20 spontaneous and 2 (10%) of 20 COH cycles (P <.05). CONCLUSION(S) Exogenous gonadotropin use in healthy reproductive age women did not result in endometrial evidence of a luteal phase defect. A greater incidence of glandular-stromal dyssynchrony resulted from the use of exogenous gonadotropins. The presence of alphavbeta3 was noted in most endometrial specimens demonstrating in phase glandular maturation. We conclude that endometrial dyssynchrony that results from delayed glandular development most likely represents a normal histologic variant.


The Journal of Infectious Diseases | 2001

Antiretroviral Therapy Effects on Genetic and Morphologic End Points in Lymphocytes and Sperm of Men with Human Immunodeficiency Virus Infection

Wendie A. Robbins; Kristine L. Witt; Joseph K. Haseman; David B. Dunson; Luigi Troiani; Myron S. Cohen; Carol D. Hamilton; Sally D. Perreault; Bishara Libbus; Stan A. Beyler; D.J. Raburn; Shelia T. Tedder; Michael D. Shelby; Jack B. Bishop

Many human immunodeficiency virus (HIV)-infected persons receive prolonged treatment with DNA-reactive antiretroviral drugs. A prospective study was conducted of 26 HIV-infected men who provided samples before treatment and at multiple times after beginning treatment, to investigate effects of antiretrovirals on lymphocyte and sperm chromosomes and semen quality. Several antiretroviral regimens, all including a nucleoside component, were used. Lymphocyte metaphase analysis and sperm fluorescence in situ hybridization were used for cytogenetic studies. Semen analyses included conventional parameters (volume, concentration, viability, motility, and morphology). No significant effects on cytogenetic parameters, semen volume, or sperm concentration were detected. However, there were significant improvements in sperm motility for men with study entry CD4 cell counts >200 cells/mm(3), sperm morphology for men with entry CD4 cell counts < or =200 cells/mm(3), and the percentage of viable sperm in both groups. These findings suggest that nucleoside-containing antiretrovirals administered via recommended protocols do not induce chromosomal changes in lymphocytes or sperm but may produce improvements in semen quality.


Biology of Reproduction | 2009

Inhibition of Human Sperm Motility by Contraceptive Anti-Eppin Antibodies from Infertile Male Monkeys: Effect on Cyclic Adenosine Monophosphate

Michael G. O'Rand; Esther E. Widgren; Stan A. Beyler; Richard T. Richardson

Abstract Epididymal protease inhibitor (eppin [official symbol, SPINLW1]) is of interest as a male contraceptive target because of its specificity and location on the human sperm surface. We have examined the effect of anti-eppin antibodies from infertile male monkeys and the effect of recombinant human semenogelin on human sperm motility. Anti-eppin antibodies significantly decreased the progressive motility of human spermatozoa as measured by decreased total distance traveled, decreased straight-line distance, and decreased velocity. Anti-eppin treatment of spermatozoa significantly increased the amount of cAMP present in nonprogressive spermatozoa; however, approximately 25% of antibody-treated spermatozoa could be rescued by the addition of cAMP-acetoxymethyl ester, indicating that anti-eppin-treated spermatozoa have a compromised ability to utilize cAMP. Addition of recombinant human semenogelin has a concentration-dependent inhibitory effect on progressive motility (increased tortuosity and decreased velocity). We tested the hypothesis that anti-eppin antibodies bound to eppin would subsequently block semenogelin binding to eppin. Anti-eppin antibodies from infertile monkeys inhibited eppin from binding to semenogelin. Addition of affinity-purified antibodies made to the dominant C-terminal epitope of eppin had an inhibitory effect on progressive motility (increased tortuosity, decreased velocity, and straight distance). Our results suggest that the eppin-semenogelin binding site is critical for the removal of semenogelin in vivo during semen liquefaction and for the initiation of progressive motility. We conclude that the eppin-semenogelin binding site on the surface of human spermatozoa is an ideal target for a nonsteroidal male contraceptive.


Biology of Reproduction | 2003

Regulated Expression of Osteopontin in the Peri-Implantation Rabbit Uterus

K.B.C. Apparao; M.J. Illera; Stan A. Beyler; Gary E. Olson; Kevin G. Osteen; Martha H. Corjay; Kim Boggess; Bruce A. Lessey

Abstract Blastocyst attachment to the lining of the mammalian uterus during early implantation involves the initial apposition of the trophoblast to the uterine epithelial surface. Osteopontin (OPN) is a glycoprotein component of the extracellular matrix that is secreted by the glandular epithelium of mammalian uteri at the time of implantation. This protein is recognized by several members of the integrin family and promotes cell-cell attachment and adhesion. In the present study, rabbit uteri were examined using Northern and in situ hybridization to evaluate the temporal and spatial distribution of OPN mRNA during early pregnancy. Northern blot analysis demonstrated a dramatic increase in OPN expression on Days 4–7 of pregnancy, corresponding to the rise in circulating progesterone and the time of initial embryo attachment in this species. In situ hybridization analysis revealed OPN mRNA expression on Day 6.75 of pregnancy, which was most prominent on endometrial epithelium. Using immunofluorescence, OPN protein was present on the glandular epithelium on Day 6.75 of pregnancy, but was absent on blastocysts. Further, no expression of OPN mRNA or protein was found in the nonpregnant endometrium. Induction of endometrial OPN expression was observed in unmated rabbits treated with progesterone alone and was prevented by cotreatment with the antiprogestin ZK137.316. Estradiol-17β had no effect on OPN expression by itself, and estrogen priming was not necessary to demonstrate the stimulatory effect of progesterone. In The rabbit uterus, as in other mammalian species studied, OPN is expressed in a stage-specific manner by the endometrial glands during the peri-implantation period and is regulated by progesterone.


Fertility and Sterility | 1999

Value of estradiol response after human chorionic gonadotropin administration in predicting in vitro fertilization success

William R. Meyer; Stan A. Beyler; Suzanne T Baker; Stephen G. Somkuti; Dawne A. Lowden; David A. Grainger

OBJECTIVE To determine whether the serum E2 response after the administration of exogenous hCG is predictive of outcome during IVF. DESIGN Prospective, noncomparative cohort. SETTING Two academic centers and one private-practice IVF program. PATIENT(S) Two hundred twenty-two couples undergoing IVF for infertility arising from ovarian dysfunction, asthenoteratospermia, endometriosis, tubal disease, or unexplained infertility. MAIN OUTCOME MEASURE(S) Implantation, pregnancy, and miscarriage rates were compared in cycles that demonstrated an increase, decrease, or plateau in the serum E2 level on the day after hCG administration. The effects of age, cause of infertility, and maximum E2 value on outcome were evaluated. RESULT(S) Ninety-two cycles resulted in a clinical pregnancy and 130 cycles failed. Of 115 cycles in which the E2 level rose, 42 (37%) resulted in an ongoing pregnancy; among cycles with plateauing E2 responses, 20 of 69 (29%) resulted in a pregnancy. Fifteen of 38 (39%) of cycles exhibiting a drop in serum E2 resulted in an ongoing pregnancy. No statistically significant differences in ongoing pregnancy rates were noted in the increasing, plateauing, or decreasing E2 response groups. CONCLUSION(S) E2 values obtained on the day after hCG administration are not predictive of outcome in women undergoing IVF.


Human Reproduction | 1997

Hydrosalpingeal fluid inhibits in-vitro embryonic development in a murine model.

Stan A. Beyler; Kay P. James; Marc A. Fritz; William R. Meyer


Fertility and Sterility | 2000

Disposition of extra embryos

Stan A. Beyler; William R. Meyer; Marc A. Fritz


Archive | 1983

Vorrichtung zum reversiblen Verschliessen eines Körpergefässes

Lourens J.D. Zaneveld; James W.P. Burns; Stan A. Beyler


Archive | 1983

Appareil pour occlure de facon réversible un vaisseau du corps

Lourens J.D. Zaneveld; James W.P. Burns; Stan A. Beyler

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Lourens J.D. Zaneveld

Rush University Medical Center

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William R. Meyer

University of North Carolina at Chapel Hill

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M.J. Illera

Complutense University of Madrid

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Lingwen Yuan

Complutense University of Madrid

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