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Assessing The Impact Of Pregnancy And Birth Factors On The Maternal And Infant Microbiota, Kait F. Al, Laura Allen, Samantha Bedell, Jeremy P. Burton, Barbra De Vrijer Jan 2023

Assessing The Impact Of Pregnancy And Birth Factors On The Maternal And Infant Microbiota, Kait F. Al, Laura Allen, Samantha Bedell, Jeremy P. Burton, Barbra De Vrijer

Obstetrics & Gynaecology Publications

Background: The microbiota acquired at birth is known to play an intimate role in later life health and disease and has been shown to be affected by the mode of birth. There has been recent interest in microbiota correction by maternal vaginal seeding in Cesarean section-born infants; however, the safety of this practice has been debated. The aim of this study was to assess how other factors, such as timing of sampling, maternal obesity, vaginal Group B Streptococcus colonization (GBS), and antibiotic exposure, affect the maternal and infant microbiota.

Methods: Maternal vaginal and saliva samples were collected at three time …


Fetal Sex Impacts Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For Regulatory Mechanisms, Bryan S. Richardson, Akasham Rajagopaul, Barbra De Vrijer, Genevieve Eastabrook, Timothy R.H. Regnault Dec 2022

Fetal Sex Impacts Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For Regulatory Mechanisms, Bryan S. Richardson, Akasham Rajagopaul, Barbra De Vrijer, Genevieve Eastabrook, Timothy R.H. Regnault

Obstetrics & Gynaecology Publications

Background: We determined the effect of fetal sex on birth/placental weight and umbilical vein and artery oxygen values with implications for placental efficiency and regulatory mechanisms underlying fetal–placental growth differences. Methods: A hospital database was used to obtain birth/placental weight, cord PO2 and other information on patients delivering between Jan 1, 1990 and Jun 15, 2011 with GA > 34 weeks (N = 69,836). Oxygen saturation was calculated from the cord PO2 and pH data, while fractional O2 extraction was calculated from the oxygen saturation data. The effect of fetal sex on birth/placental weight, cord PO2, O2 saturation, and fractional O2 …


Expression And Localization Of Nrf2/Keap1 Signalling Pathway Genes In Mouse Preimplantation Embryos Exposed To Free Fatty Acids., Grace Dionne, Michele D. Calder, Dean H Betts, Basim Abu Rafea, Andrew J Watson Dec 2022

Expression And Localization Of Nrf2/Keap1 Signalling Pathway Genes In Mouse Preimplantation Embryos Exposed To Free Fatty Acids., Grace Dionne, Michele D. Calder, Dean H Betts, Basim Abu Rafea, Andrew J Watson

Obstetrics & Gynaecology Publications

Obese women experience greater incidence of infertility, with reproductive tracts exposing preimplantation embryos to elevated free fatty acids (FFA) such as palmitic acid (PA) and oleic acid (OA). PA treatment impairs mouse preimplantation development in vitro, while OA co-treatment rescues blastocyst development of PA treated embryos. In the present study, we investigated the effects of PA and OA treatment on NRF2/Keap1 localization, and relative antioxidant enzyme (Glutathione peroxidase; Gpx1, Catalase; Cat, Superoxide dismutase; Sod1 and γ-Glutamylcysteine ligase catalytic unit; Gclc) mRNA levels, during in vitro mouse preimplantation embryo development. Female mice were superovulated, mated, and embryos cultured in the presence …


Ecological Interchangeability: Supporting Team Adaptive Expertise In Moments Of Disruption, Sayra Cristancho, Emily Field, Lorelei Lingard, Taryn Taylor, Kathryn Hibbert, Graham Thompson, William Hibbert Dec 2022

Ecological Interchangeability: Supporting Team Adaptive Expertise In Moments Of Disruption, Sayra Cristancho, Emily Field, Lorelei Lingard, Taryn Taylor, Kathryn Hibbert, Graham Thompson, William Hibbert

Obstetrics & Gynaecology Publications

While undesirable, unexpected disruptions offer unique opportunities to enact adaptive expertise. For adaptive expertise to flourish, individuals and teams must embrace both efficiency and adaptation. While some industries do it readily, others continue to struggle with the tension between efficiency and adaptation, particularly when otherwise stable situations are unexpectedly disrupted. For instance, in healthcare settings, the efficiency mandate for strict compliance with scopes of practice can deter teams from using the adaptive strategy of making their members interchangeable. Yet, interchangeability has been hinted as a key capacity of today’ teams that are required to navigate fluid team structures. Because interchangeability …


Facing Hierarchy: A Qualitative Study Of Residents' Experiences In An Obstetrical Simulation Scenario, Adam B Garber, Glenn Posner, Taylor Roebotham, M Dylan Bould, Taryn Taylor Oct 2022

Facing Hierarchy: A Qualitative Study Of Residents' Experiences In An Obstetrical Simulation Scenario, Adam B Garber, Glenn Posner, Taylor Roebotham, M Dylan Bould, Taryn Taylor

Obstetrics & Gynaecology Publications

BACKGROUND: Residents in surgical specialties face a steep hierarchy when managing medical crises. Hierarchy can negatively impact patient safety when team members are reluctant to speak up. Yet, simulation has scarcely been previously utilized to qualitatively explore the way residents in surgical specialities navigate this challenge. The study aimed to explore the experiences of residents in one surgical specialty, obstetrics and gynecology (Ob/Gyn), when challenging hierarchy, with the goal of informing future interventions to optimize resident learning and patient safety.

METHODS: Eight 3rd- and 4th-year Ob/Gyn residents participated in a simulation scenario in which their supervising physician made an erroneous …


Highlighting The Mechanistic Relationship Between Perinatal Depression And Preeclampsia: A Scoping Review, Mei Yuan, Samantha Bedell, Barbra De Vrijer, Genevieve Eastabrook, Jefferson C. Frisbee, Stephanie J. Frisbee Oct 2022

Highlighting The Mechanistic Relationship Between Perinatal Depression And Preeclampsia: A Scoping Review, Mei Yuan, Samantha Bedell, Barbra De Vrijer, Genevieve Eastabrook, Jefferson C. Frisbee, Stephanie J. Frisbee

Obstetrics & Gynaecology Publications

Background: Although there is scientific literature supporting an association between depression and preeclampsia (PE), little is known about the underlying mechanistic pathways that may explain these observed associations. Thus, this study aimed to outline the relationship between depression and PE, and to highlight the underlying cardiovascular and metabolic risk factors that are common to both. Methods: A scoping review of the literature was conducted in Medline, Scopus, and Web of Science. Results: From 706 articles initially identified, 23 articles met the inclusion criteria and were included in this review. Although some studies reported a positive association between PE and postpartum …


"Maybe I'M Not That Approachable": Using Simulation To Elicit Team Leaders' Perceptions Of Their Role In Facilitating Speaking Up Behaviors, Rachael Pack, Lauren Columbus, Trevor Hines Duncliffe, Harrison Banner, Priyanka Singh, Natashia Seemann, Taryn Taylor Jan 2022

"Maybe I'M Not That Approachable": Using Simulation To Elicit Team Leaders' Perceptions Of Their Role In Facilitating Speaking Up Behaviors, Rachael Pack, Lauren Columbus, Trevor Hines Duncliffe, Harrison Banner, Priyanka Singh, Natashia Seemann, Taryn Taylor

Obstetrics & Gynaecology Publications

BACKGROUND: Simulation research that seeks to solve the problem of silence among interprofessional teams has focused almost exclusively on training subordinate team members to be more courageous and to speak up to team leaders using direct challenge scripts despite the great interpersonal cost. Consequently, the existing literature overemphasizes the responsibility of subordinate team members for speaking up and fails to consider the role and responsibilities of team leaders in sustaining silence. The purpose of this study is to identify and describe the subtle behaviors and actions of team leaders that both promote and discourage speaking up.

METHODS: This study used …


Gestational Age Impacts Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For The Fetal Oxygen Margin Of Safety, Bryan S Richardson, Barbra De Vrijer, Hilary K Brown, Larry Stitt, Sheryl Choo, Timothy R H Regnault Jan 2022

Gestational Age Impacts Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For The Fetal Oxygen Margin Of Safety, Bryan S Richardson, Barbra De Vrijer, Hilary K Brown, Larry Stitt, Sheryl Choo, Timothy R H Regnault

Obstetrics & Gynaecology Publications

Background: We determined the impact of gestational age (GA) from near term to term to post-term on birth/placental weight ratio and cord oxygen values with implications for placental transport efficiency for oxygen, fetal O2 consumption relative to delivery or fractional O2 extraction, and oxygen margin of safety.

Materials and methods: A hospital database was used to obtain birth/placental weight ratios, cord PO2 and other information on patients delivering between Jan 1, 1990 and Jun 15, 2011 with GA > 34 completed weeks (N=69,852). Oxygen saturation was calculated from the cord PO2 and pH data, while fractional O2 extraction was calculated from …


The Fatigue Paradox: Team Perceptions Of Physician Fatigue, Emily Field, Lorelei Lingard, Richard Cherry, Julie Ann Van Koughnett, Sandra Deluca, Taryn Taylor Dec 2021

The Fatigue Paradox: Team Perceptions Of Physician Fatigue, Emily Field, Lorelei Lingard, Richard Cherry, Julie Ann Van Koughnett, Sandra Deluca, Taryn Taylor

Obstetrics & Gynaecology Publications

OBJECTIVES: Ongoing calls to implement fatigue risk management in residency education assume a shared understanding of physician fatigue as a workplace hazard, yet we lack empirical evidence that all health care team members maintain this assumption. Thus, this study seeks to explore how health care team members understand the role of physician fatigue in an effort to inform the implementation of fatigue risk management in residency training and medical practice.

METHODS: This study uses constructivist grounded theory to explore perceptions of workplace fatigue and its impact on clinical practice. We conducted individual semi-structured interviews with physicians, nurses and senior residents …


Structural Distress: Experiences Of Moral Distress Related To Structural Stigma During The Covid-19 Pandemic, Javeed Sukhera, Chetana Kulkarni, Taryn Taylor Aug 2021

Structural Distress: Experiences Of Moral Distress Related To Structural Stigma During The Covid-19 Pandemic, Javeed Sukhera, Chetana Kulkarni, Taryn Taylor

Obstetrics & Gynaecology Publications

INTRODUCTION: The COVID-19 pandemic has taken a significant toll on the health of structurally vulnerable patient populations as well as healthcare workers. The concepts of structural stigma and moral distress are important and interrelated, yet rarely explored or researched in medical education. Structural stigma refers to how discrimination towards certain groups is enacted through policy and practice. Moral distress describes the tension and conflict that health workers experience when they are unable to fulfil their duties due to circumstances outside of their control. In this study, the authors explored how resident physicians perceive moral distress in relation to structural stigma. …


Water-Fat Magnetic Resonance Imaging Of Adipose Tissue Compartments In The Normal Third Trimester Fetus, Stephanie A Giza, Tianna L Koreman, Simran Sethi, Michael R Miller, Debbie A Penava, Genevieve D Eastabrook, Charles A Mckenzie, Barbra De Vrijer Jun 2021

Water-Fat Magnetic Resonance Imaging Of Adipose Tissue Compartments In The Normal Third Trimester Fetus, Stephanie A Giza, Tianna L Koreman, Simran Sethi, Michael R Miller, Debbie A Penava, Genevieve D Eastabrook, Charles A Mckenzie, Barbra De Vrijer

Obstetrics & Gynaecology Publications

BACKGROUND: Assessment of fetal adipose tissue gives information about the future metabolic health of an individual, with evidence that the development of this tissue has regional heterogeneity.

OBJECTIVE: To assess differences in the proton density fat fraction (PDFF) between fetal adipose tissue compartments in the third trimester using water-fat magnetic resonance imaging (MRI).

MATERIALS AND METHODS: Water-fat MRI was performed in a 1.5-T scanner. Fetal adipose tissue was segmented into cheeks, thorax, abdomen, upper arms, forearms, thighs and lower legs. PDFF and R2* values were measured in each compartment.

RESULTS: Twenty-eight women with singleton pregnancies were imaged between 28 and …


Effects Of Maternal Obesity And Gestational Diabetes Mellitus On The Placenta: Current Knowledge And Targets For Therapeutic Interventions, Samantha Bedell, Janine Hutson, Barbra De Vrijer, Genevieve Eastabrook Jan 2021

Effects Of Maternal Obesity And Gestational Diabetes Mellitus On The Placenta: Current Knowledge And Targets For Therapeutic Interventions, Samantha Bedell, Janine Hutson, Barbra De Vrijer, Genevieve Eastabrook

Obstetrics & Gynaecology Publications

Obesity and gestational diabetes mellitus (GDM) are becoming more common among pregnant women worldwide and are individually associated with a number of placenta-mediated obstetric complications, including preeclampsia, macrosomia, intrauterine growth restriction and stillbirth. The placenta serves several functions throughout pregnancy and is the main exchange site for the transfer of nutrients and gas from mother to fetus. In pregnancies complicated by maternal obesity or GDM, the placenta is exposed to environmental changes, such as increased inflammation and oxidative stress, dyslipidemia, and altered hormone levels. These changes can affect placental development and function and lead to abnormal fetal growth and development …


Maternal Obesity Reduces Placental Autophagy Marker Expression In Uncomplicated Pregnancies, Matthew Cohen, Emily Guo, Aidan Pucchio, Barbra De Vrijer, Trevor G Shepherd, Genevieve Eastabrook Aug 2020

Maternal Obesity Reduces Placental Autophagy Marker Expression In Uncomplicated Pregnancies, Matthew Cohen, Emily Guo, Aidan Pucchio, Barbra De Vrijer, Trevor G Shepherd, Genevieve Eastabrook

Obstetrics & Gynaecology Publications

AIM: Obesity has been associated with changes in autophagy and its increasing prevalence among pregnant women is implicated in higher rates of placental-mediated complications of pregnancy such as pre-eclampsia and intrauterine growth restriction. Autophagy is involved in normal placentation, thus changes in autophagy may lead to impaired placental function and development. The aim of this study was to investigate the connection between obesity and autophagy in the placenta in otherwise uncomplicated pregnancies.

METHODS: Immunohistochemistry and western blot analysis were done on placental and omental samples from obese (body mass index [BMI] ≥30 kg/m

RESULTS: As pre-pregnancy BMI increased, there was …


Labour Progression In Obese Women: Are Women With Increased Body Mass Index Having Unnecessary Cesarean Sections?, Caroline Shenouda, Aloka Wijesooriya, Amanda Toufeili, Michael R Miller, Debbie Penava, Barbra De Vrijer Mar 2020

Labour Progression In Obese Women: Are Women With Increased Body Mass Index Having Unnecessary Cesarean Sections?, Caroline Shenouda, Aloka Wijesooriya, Amanda Toufeili, Michael R Miller, Debbie Penava, Barbra De Vrijer

Obstetrics & Gynaecology Publications

OBJECTIVE: This study sought to determine whether obese pregnant women undergo cesarean sections without an adequate trial of labour. This may affect future birth and pregnancy outcomes.

METHODS: A retrospective analysis was done on 526 parturients at Victoria Hospital in London, Ontario. Women were categorized according to parity and pre-pregnancy body mass index (BMI; normal weight, BMI 18.5-24.9 kg/m

RESULTS: Obese class II and III primiparous women required an additional 1.62 and 2.67 hours (P = 0.012), respectively, to reach a dilation of 10 cm compared with their normal weight counterparts; obese class II and III multiparous women required an …


Perseverance, Faith And Stoicism: A Qualitative Study Of Medical Student Perspectives On Managing Fatigue, Taryn S Taylor, Alexandra L Raynard, Lorelei Lingard Dec 2019

Perseverance, Faith And Stoicism: A Qualitative Study Of Medical Student Perspectives On Managing Fatigue, Taryn S Taylor, Alexandra L Raynard, Lorelei Lingard

Obstetrics & Gynaecology Publications

CONTEXT: Fatigue risk management (FRM) strategies offer a potential solution to the widespread problem of fatigued trainees in the clinical workplace. These strategies assume a shared perception that fatigue is hazardous. Despite the growing body of evidence suggesting that fatigue leads to burnout and medical errors, previous research suggests that residents perceive fatigue as a personal, surmountable burden rather than an occupational hazard. Before we can implement FRM, we need a better understanding of when and how such problematic notions of fatigue are adopted by medical trainees. Thus, we sought to explore how third-year medical students understand and manage the …


Direct Genetics Referral Pathway For High-Grade Serous Ovarian Cancer Patients: The "Opt-Out" Process, Jacob Mcgee, Teresa M. Peart, Norine Foley, Monique Bertrand, Michel Prefontaine, Akira Sugimoto, Helen Ettler, Stephen Welch, Karen Panabaker Jan 2019

Direct Genetics Referral Pathway For High-Grade Serous Ovarian Cancer Patients: The "Opt-Out" Process, Jacob Mcgee, Teresa M. Peart, Norine Foley, Monique Bertrand, Michel Prefontaine, Akira Sugimoto, Helen Ettler, Stephen Welch, Karen Panabaker

Obstetrics & Gynaecology Publications

Purpose. In order to meet a clinical need for better pathways to access genetic testing for ovarian cancer patients, we implemented and reviewed an opt-out referral process for genetic consultation whereby a referral is automatically sent to genetics following a pathological diagnosis of HGSC. Methods. Following implementation of the opt-out referral process, each month a list of new cases of HGSC was generated from the synoptic pathology report and forwarded directly to the Cancer Genetics clinic. Using an advanced directive, patients were automatically referred for genetic counselling two months after surgery. If the patient declined genetic counselling (opted-out) after discussion …


Preeclampsia Biomarkers: An Assessment Of Maternal Cardiometabolic Health, Genevieve Eastabrook, Tuba Aksoy, Samantha Bedell, Debbie Penava, Barbra De Vrijer Jul 2017

Preeclampsia Biomarkers: An Assessment Of Maternal Cardiometabolic Health, Genevieve Eastabrook, Tuba Aksoy, Samantha Bedell, Debbie Penava, Barbra De Vrijer

Obstetrics & Gynaecology Publications

No abstract provided.


Effects Of American Ginseng On Preimplantation Development And Pregnancy In Mice., Danyka Belanger, Michele D Calder, Alessandra Gianetto-Berruti, Edmund M Lui, Andrew J Watson, Valter Feyles Jul 2016

Effects Of American Ginseng On Preimplantation Development And Pregnancy In Mice., Danyka Belanger, Michele D Calder, Alessandra Gianetto-Berruti, Edmund M Lui, Andrew J Watson, Valter Feyles

Obstetrics & Gynaecology Publications

In North America, a high proportion of pregnant women use herbal medications including North American ginseng. This medicinal plant contains high amounts of triterpene saponins (ginsenosides), which are the main bioactive compounds. It is important to assess ginseng's impact on all reproductive functions to ensure the safety of pregnant women and fetuses. In this study, we defined the concentration-responsive effects of North American alcoholic and aqueous ginseng extracts on preimplantation development in vitro and on pregnancy and post-partum development in the mouse. Two-cell mouse embryos were cultured with 5 different concentrations of whole ginseng root extracts, or ginsenosides Rb1, Rg1 …


P66shc, A Key Regulator Of Metabolism And Mitochondrial Ros Production, Is Dysregulated By Mouse Embryo Culture., Nicole A Edwards, Andrew J Watson, Dean H Betts Jul 2016

P66shc, A Key Regulator Of Metabolism And Mitochondrial Ros Production, Is Dysregulated By Mouse Embryo Culture., Nicole A Edwards, Andrew J Watson, Dean H Betts

Obstetrics & Gynaecology Publications

STUDY QUESTION: Do high oxygen tension and high glucose concentrations dysregulate p66Shc (Src homologous-collagen homologue adaptor protein) expression during mouse preimplantation embryo culture?

SUMMARY ANSWER: Compared with mouse blastocysts in vivo, P66Shc mRNA and protein levels in blastocysts maintained in vitro increased under high oxygen tension (21%), but not high glucose concentration.

WHAT IS KNOWN ALREADY: Growth in culture adversely impacts preimplantation embryo development and alters the expression levels of the oxidative stress adaptor protein p66Shc, but it is not known if p66Shc expression is linked to metabolic changes observed in cultured embryos.

STUDY DESIGN, SAMPLES/MATERIALS, METHODS: We used a …


Principles Of Fatigue In Residency Education: A Qualitative Study, Taryn S Taylor, Christopher J Watling, Pim W Teunissen, Tim Dornan, Lorelei Lingard Jan 2016

Principles Of Fatigue In Residency Education: A Qualitative Study, Taryn S Taylor, Christopher J Watling, Pim W Teunissen, Tim Dornan, Lorelei Lingard

Obstetrics & Gynaecology Publications

BACKGROUND: Proposals to implement fatigue-management strategies in residency education assume that medicine shares the view of other risk-adverse industries that fatigue is hazardous. This view is an essential underpinning of fatigue-management strategies that other industries have embedded as part of their workplace occupational health and safety programs. We sought to explore how residents understand fatigue in the context of their training environment.

METHODS: We interviewed 21 residents in 7 surgical and nonsurgical programs at Western University in 2014. All participants met the inclusion criteria of routinely working 24-hour call shifts while enrolled in their training program. Data collection and analysis …


Evidence For Differential Viral Oncolytic Efficacy In An In Vitro Model Of Epithelial Ovarian Cancer Metastasis, Jessica G. Tong, Yudith Ramos Valdes, John W. Barrett, John C. Bell, David Stojdl, Grant Mcfadden, J. Andrea Mccart, Gabriel E. Dimattia, Trevor G. Shepherd Sep 2015

Evidence For Differential Viral Oncolytic Efficacy In An In Vitro Model Of Epithelial Ovarian Cancer Metastasis, Jessica G. Tong, Yudith Ramos Valdes, John W. Barrett, John C. Bell, David Stojdl, Grant Mcfadden, J. Andrea Mccart, Gabriel E. Dimattia, Trevor G. Shepherd

Obstetrics & Gynaecology Publications

Epithelial ovarian cancer is unique among most carcinomas in that metastasis occurs by direct dissemination of malignant cells traversing throughout the intraperitoneal fluid. Accordingly, we test new therapeutic strategies using an in vitro three-dimensional spheroid suspension culture model that mimics key steps of this metastatic process. In the present study, we sought to uncover the differential oncolytic efficacy among three different viruses—Myxoma virus, double-deleted vaccinia virus, and Maraba virus—using three ovarian cancer cell lines in our metastasis model system. Herein, we demonstrate that Maraba virus effectively infects, replicates, and kills epithelial ovarian cancer (EOC) cells in proliferating adherent cells and …


Simulated Diabetic Ketoacidosis Therapy In Vitro Elicits Brain Cell Swelling Via Sodium-Hydrogen Exchange And Anion Transport., Keeley L Rose, Andrew J Watson, Thomas A Drysdale, Gediminas Cepinskas, Melissa Chan, C Anthony Rupar, Douglas D Fraser Aug 2015

Simulated Diabetic Ketoacidosis Therapy In Vitro Elicits Brain Cell Swelling Via Sodium-Hydrogen Exchange And Anion Transport., Keeley L Rose, Andrew J Watson, Thomas A Drysdale, Gediminas Cepinskas, Melissa Chan, C Anthony Rupar, Douglas D Fraser

Obstetrics & Gynaecology Publications

A common complication of type 1 diabetes mellitus is diabetic ketoacidosis (DKA), a state of severe insulin deficiency. A potentially harmful consequence of DKA therapy in children is cerebral edema (DKA-CE); however, the mechanisms of therapy-induced DKA-CE are unknown. Our aims were to identify the DKA treatment factors and membrane mechanisms that might contribute specifically to brain cell swelling. To this end, DKA was induced in juvenile mice with the administration of the pancreatic toxins streptozocin and alloxan. Brain slices were prepared and exposed to DKA-like conditions in vitro. Cell volume changes were imaged in response to simulated DKA therapy. …


Implantation Failure In Female Kiss1-/- Mice Is Independent Of Their Hypogonadic State And Can Be Partially Rescued By Leukemia Inhibitory Factor., Michele Calder, Yee-Ming Chan, Renju Raj, Macarena Pampillo, Adrienne Elbert, Michelle Noonan, Carolina Gillio-Meina, Claudia Caligioni, Nathalie G Bérubé, Moshmi Bhattacharya, Andrew J Watson, Stephanie B Seminara, Andy V Babwah Aug 2014

Implantation Failure In Female Kiss1-/- Mice Is Independent Of Their Hypogonadic State And Can Be Partially Rescued By Leukemia Inhibitory Factor., Michele Calder, Yee-Ming Chan, Renju Raj, Macarena Pampillo, Adrienne Elbert, Michelle Noonan, Carolina Gillio-Meina, Claudia Caligioni, Nathalie G Bérubé, Moshmi Bhattacharya, Andrew J Watson, Stephanie B Seminara, Andy V Babwah

Obstetrics & Gynaecology Publications

The hypothalamic kisspeptin signaling system is a major positive regulator of the reproductive neuroendocrine axis, and loss of Kiss1 in the mouse results in infertility, a condition generally attributed to its hypogonadotropic hypogonadism. We demonstrate that in Kiss1(-/-) female mice, acute replacement of gonadotropins and estradiol restores ovulation, mating, and fertilization; however, these mice are still unable to achieve pregnancy because embryos fail to implant. Progesterone treatment did not overcome this defect. Kiss1(+/-) embryos transferred to a wild-type female mouse can successfully implant, demonstrating the defect is due to maternal factors. Kisspeptin and its receptor are expressed in the mouse …


Stress-Inducible Phosphoprotein 1 Has Unique Cochaperone Activity During Development And Regulates Cellular Response To Ischemia Via The Prion Protein., Flavio H Beraldo, Iaci N Soares, Daniela F Goncalves, Jue Fan, Anu A Thomas, Tiago G Santos, Amro H Mohammad, Martin Roffé, Michele D Calder, Simona Nikolova, Glaucia N Hajj, Andre L Guimaraes, Andre R Massensini, Ian Welch, Dean H Betts, Robert Gros, Maria Drangova, Andrew J Watson, Robert Bartha, Vania F Prado, Vilma R Martins, Marco A M Prado Sep 2013

Stress-Inducible Phosphoprotein 1 Has Unique Cochaperone Activity During Development And Regulates Cellular Response To Ischemia Via The Prion Protein., Flavio H Beraldo, Iaci N Soares, Daniela F Goncalves, Jue Fan, Anu A Thomas, Tiago G Santos, Amro H Mohammad, Martin Roffé, Michele D Calder, Simona Nikolova, Glaucia N Hajj, Andre L Guimaraes, Andre R Massensini, Ian Welch, Dean H Betts, Robert Gros, Maria Drangova, Andrew J Watson, Robert Bartha, Vania F Prado, Vilma R Martins, Marco A M Prado

Obstetrics & Gynaecology Publications

Stress-inducible phosphoprotein 1 (STI1) is part of the chaperone machinery, but it also functions as an extracellular ligand for the prion protein. However, the physiological relevance of these STI1 activities in vivo is unknown. Here, we show that in the absence of embryonic STI1, several Hsp90 client proteins are decreased by 50%, although Hsp90 levels are unaffected. Mutant STI1 mice showed increased caspase-3 activation and 50% impairment in cellular proliferation. Moreover, placental disruption and lack of cellular viability were linked to embryonic death by E10.5 in STI1-mutant mice. Rescue of embryonic lethality in these mutants, by transgenic expression of the …


Endogenous Folate Accumulation In Oocytes And Preimplantation Embryos And Its Epigenetic Implications., Mellissa R W Mann, Andrew J Watson Sep 2013

Endogenous Folate Accumulation In Oocytes And Preimplantation Embryos And Its Epigenetic Implications., Mellissa R W Mann, Andrew J Watson

Obstetrics & Gynaecology Publications

No abstract provided.


P38 Mapk Regulates Cavitation And Tight Junction Function In The Mouse Blastocyst., Christine E Bell, Andrew J Watson Jan 2013

P38 Mapk Regulates Cavitation And Tight Junction Function In The Mouse Blastocyst., Christine E Bell, Andrew J Watson

Obstetrics & Gynaecology Publications

UNLABELLED: Blastocyst formation is essential for implantation and maintenance of pregnancy and is dependent on the expression and coordinated function of a series of proteins involved in establishing and maintaining the trans-trophectoderm ion gradient that enables blastocyst expansion. These consist of Na/K-ATPase, adherens junctions, tight junctions (TJ) and aquaporins (AQP). While their role in supporting blastocyst formation is established, the intracellular signaling pathways that coordinate their function is unclear. The p38 MAPK pathway plays a role in regulating these proteins in other cell types and is required for embryo development at the 8-16 cell stage, but its role has not …


Embryo Collection Induces Transient Activation Of Xbp1 Arm Of The Er Stress Response While Embryo Vitrification Does Not., Tamara Abraham, Christopher L Pin, Andrew J Watson May 2012

Embryo Collection Induces Transient Activation Of Xbp1 Arm Of The Er Stress Response While Embryo Vitrification Does Not., Tamara Abraham, Christopher L Pin, Andrew J Watson

Obstetrics & Gynaecology Publications

Embryo cryopreservation has become a standard procedure in the practice of assisted reproduction. While routinely performed in IVF labs, the effects of embryo vitrification on the molecular mechanisms governing preimplantation development remain largely unknown. The endoplasmic reticulum stress (ER stress) response is an evolutionary conserved mechanism that cells employ to manage ER stress. ER stress can be defined as an imbalance between protein synthesis and secretion within the ER. The primary focus of this study was to investigate whether standard embryo manipulations, including embryo collection, culture and vitrification, result in activation of the ER stress pathway in vitro and to …


Outer Space And Oocyte Developmental Competence., Andrew J Watson Mar 2012

Outer Space And Oocyte Developmental Competence., Andrew J Watson

Obstetrics & Gynaecology Publications

No abstract provided.


Culture Medium, Gas Atmosphere And Mapk Inhibition Affect Regulation Of Rna-Binding Protein Targets During Mouse Preimplantation Development., Michele D Calder, Patricia H Watson, Andrew J Watson Nov 2011

Culture Medium, Gas Atmosphere And Mapk Inhibition Affect Regulation Of Rna-Binding Protein Targets During Mouse Preimplantation Development., Michele D Calder, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

During oogenesis, mammalian oocytes accumulate maternal mRNAs that support the embryo until embryonic genome activation. RNA-binding proteins (RBP) may regulate the stability and turnover of maternal and embryonic mRNAs. We hypothesised that varying embryo culture conditions, such as culture medium, oxygen tension and MAPK inhibition, affects regulation of RBPs and their targets during preimplantation development. STAU1, ELAVL1, KHSRP and ZFP36 proteins and mRNAs were detected throughout mouse preimplantation development, whereas Elavl2 mRNA decreased after the two-cell stage. Potential target mRNAs of RBP regulation, Gclc, Slc2a1 and Slc7a1 were detected during mouse preimplantation development. Gclc mRNA was significantly elevated in embryos …


Ouabain Stimulates A Na+/K+-Atpase-Mediated Sfk-Activated Signalling Pathway That Regulates Tight Junction Function In The Mouse Blastocyst., Holly Giannatselis, Michele Calder, Andrew J Watson Jan 2011

Ouabain Stimulates A Na+/K+-Atpase-Mediated Sfk-Activated Signalling Pathway That Regulates Tight Junction Function In The Mouse Blastocyst., Holly Giannatselis, Michele Calder, Andrew J Watson

Obstetrics & Gynaecology Publications

The Na(+)/K(+)-ATPase plays a pivotal role during preimplantation development; it establishes a trans-epithelial ionic gradient that facilitates the formation of the fluid-filled blastocyst cavity, crucial for implantation and successful pregnancy. The Na(+)/K(+)-ATPase is also implicated in regulating tight junctions and cardiotonic steroid (CTS)-induced signal transduction via SRC. We investigated the expression of SRC family kinase (SFK) members, Src and Yes, during preimplantation development and determined whether SFK activity is required for blastocyst formation. Embryos were collected following super-ovulation of CD1 or MF1 female mice. RT-PCR was used to detect SFK mRNAs encoding Src and Yes throughout preimplantation development. SRC and …