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Full-Text Articles in Medicine and Health Sciences
The Impact Of Maternal Diabetes On Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For Fetal-Placental Development, Sheryl Choo, Barbra De Vrijer, Timothy R H Regnault, Hilary K Brown, Larry Stitt, Bryan S Richardson
The Impact Of Maternal Diabetes On Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For Fetal-Placental Development, Sheryl Choo, Barbra De Vrijer, Timothy R H Regnault, Hilary K Brown, Larry Stitt, Bryan S Richardson
Obstetrics & Gynaecology Publications
Introduction
We determined the impact of gestational diabetes (GDM) and pre-existing diabetes (DM) on birth/placental weight and cord oxygen values with implications for placental efficiency and fetal-placental growth and development.
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 = 69,854). Oxygen saturation was calculated from the cord PO2 and pH data, while fetal O2 extraction was calculated from the oxygen saturation data. The effect of diabetic status on birth/placental weight and cord oxygen values …
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
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
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
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
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
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
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
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
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 …
Oocyte Peptides As Paracrine Tools For Ovarian Stimulation And Oocyte Maturation., David G Mottershead, Andrew J Watson
Oocyte Peptides As Paracrine Tools For Ovarian Stimulation And Oocyte Maturation., David G Mottershead, Andrew J Watson
Obstetrics & Gynaecology Publications
Recent studies report the production and isolation of a stable bioactive recombinant human bone morphogenetic protein 15 (rhBMP15) that is appropriately processed in HEK-293 cells and activates the SMAD 1/5/8 pathway in mouse granulosa cell cultures. Further, the purified rhBMP15 induces the expression of genes associated with cumulus expansion. Thanks to recent research, we have a greater understanding of the importance of the dialogue that occurs between the oocyte and the granulosa cell layer with regard to regulating folliculogenesis and the acquisition of oocyte developmental competence and maturation. BMP15 is one of the critical components of these intra-follicular communication pathways. …
Genomic Rna Profiling And The Programme Controlling Preimplantation Mammalian Development., Christine E Bell, Michele D Calder, Andrew J Watson
Genomic Rna Profiling And The Programme Controlling Preimplantation Mammalian Development., Christine E Bell, Michele D Calder, Andrew J Watson
Obstetrics & Gynaecology Publications
Preimplantation development shifts from a maternal to embryonic programme rapidly after fertilization. Although the majority of oogenetic products are lost during the maternal to embryonic transition (MET), several do survive this interval to contribute directly to supporting preimplantation development. Embryonic genome activation (EGA) is characterized by the transient expression of several genes that are necessary for MET, and while EGA represents the first major wave of gene expression, a second mid-preimplantation wave of transcription that supports development to the blastocyst stage has been discovered. The application of genomic approaches has greatly assisted in the discovery of stage specific gene expression …
Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan
Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan
Obstetrics & Gynaecology Publications
Preimplantation development directs the formation of an implantation- or attachment-competent embryo so that metabolic interactions with the uterus can occur, pregnancy can be initiated, and fetal development can be sustained. The preimplantation embryo exhibits a form of autonomous development fueled by products provided by the oocyte and also from activation of the embryo's genome. Despite this autonomy, the preimplantation embryo is highly influenced by factors in the external environment and in extreme situations, such as those presented by embryo culture or nuclear transfer, the ability of the embryo to adapt to the changing environmental conditions or chromatin to become reprogrammed …
Oocyte Cytoplasmic Maturation: A Key Mediator Of Oocyte And Embryo Developmental Competence., A J Watson
Oocyte Cytoplasmic Maturation: A Key Mediator Of Oocyte And Embryo Developmental Competence., A J Watson
Obstetrics & Gynaecology Publications
Efforts have intensified to successfully mature and inseminate oocytes in vitro and then culture ensuing embryos to transferable stages from a large number of mammalian species. Success varies, but generally even for the most successful species it is only possible to obtain a maximum of a 40 to 50% development of zygotes to the blastocyst stage. Reduced oocyte developmental competence is suggested as a primary reason for the reduced potential of in vitro-produced embryos. The vast majority of in vitro-matured oocytes are meiotically competent; however, many do not attain an optimal oocyte diameter before insemination. Variations in oocyte in vitro …
Roles Of Na,K-Atpase In Early Development And Trophectoderm Differentiation., Gerald M Kidder, Andrew J Watson
Roles Of Na,K-Atpase In Early Development And Trophectoderm Differentiation., Gerald M Kidder, Andrew J Watson
Obstetrics & Gynaecology Publications
Before implantation into the uterine wall, the mammalian embryo undergoes a period of cell division, cell shape change, and cell differentiation leading to the formation of an outer epithelium, the trophectoderm. The trophectoderm is the part of the embryo that initiates uterine contact and, after transformation to become the trophoblast, uterine invasion. Similar to the kidney nephron, the trophectoderm is a transporting epithelium with distinct apical and basolateral membrane domains; its function is to facilitate transepithelial Na+ and fluid transport for blastocoel formation. That transport is driven by Na,K-adenosine triphosphatase (ATPase) localized in basolateral membranes of the trophectoderm. Preimplantation embryos …
Rgs14 Is A Mitotic Spindle Protein Essential From The First Division Of The Mammalian Zygote., Luke Martin-Mccaffrey, Francis S Willard, Antonio J Oliveira-Dos-Santos, David R C Natale, Bryan E Snow, Randall J Kimple, Agnieszka Pajak, Andrew J Watson, Lina Dagnino, Josef M Penninger, David P Siderovski, Sudhir J A D'Souza
Rgs14 Is A Mitotic Spindle Protein Essential From The First Division Of The Mammalian Zygote., Luke Martin-Mccaffrey, Francis S Willard, Antonio J Oliveira-Dos-Santos, David R C Natale, Bryan E Snow, Randall J Kimple, Agnieszka Pajak, Andrew J Watson, Lina Dagnino, Josef M Penninger, David P Siderovski, Sudhir J A D'Souza
Obstetrics & Gynaecology Publications
Heterotrimeric G protein alpha subunits, RGS proteins, and GoLoco motif proteins have been recently implicated in the control of mitotic spindle dynamics in C. elegans and D. melanogaster. Here we show that "regulator of G protein signaling-14" (RGS14) is expressed by the mouse embryonic genome immediately prior to the first mitosis, where it colocalizes with the anastral mitotic apparatus of the mouse zygote. Loss of Rgs14 expression in the mouse zygote results in cytofragmentation and failure to progress to the 2-cell stage. RGS14 is found in all tissues and segregates to the nucleus in interphase and to the mitotic spindle …
Responsiveness Of Bovine Cumulus-Oocyte-Complexes (Coc) To Porcine And Recombinant Human Fsh, And The Effect Of Coc Quality On Gonadotropin Receptor And Cx43 Marker Gene Mrnas During Maturation In Vitro., Michele D Calder, Anita N Caveney, Lawrence C Smith, Andrew J Watson
Responsiveness Of Bovine Cumulus-Oocyte-Complexes (Coc) To Porcine And Recombinant Human Fsh, And The Effect Of Coc Quality On Gonadotropin Receptor And Cx43 Marker Gene Mrnas During Maturation In Vitro., Michele D Calder, Anita N Caveney, Lawrence C Smith, Andrew J Watson
Obstetrics & Gynaecology Publications
Substantially less development to the blastocyst stage occurs in vitro than in vivo and this may be due to deficiencies in oocyte competence. Although a large proportion of bovine oocytes undergo spontaneous nuclear maturation, less is known about requirements for proper cytoplasmic maturation. Commonly, supraphysiological concentrations of FSH and LH are added to maturation media to improve cumulus expansion, fertilization and embryonic development. Therefore, various concentrations of porcine FSH (pFSH) and recombinant human FSH (rhFSH) were investigated for their effect on bovine cumulus expansion in vitro. Expression of FSHr, LHr and Cx43 mRNAs was determined in cumulus-oocyte complexes to determine …
Regulation Of Blastocyst Formation., A J Watson, L C Barcroft
Regulation Of Blastocyst Formation., A J Watson, L C Barcroft
Obstetrics & Gynaecology Publications
Preimplantation or pre-attachment development encompasses the "free"-living period of mammalian embryogenesis, which directs development of the zygote through to the blastocyst stage. Blastocyst formation is essential for implantation, establishment of pregnancy and is a principal determinant of embryo quality prior to embryo transfer. Cavitation (blastocyst formation) is driven by the expression of specific sets of gene products that direct the acquisition of cell polarity within the trophectoderm, which is both the first epithelium of development and the outer cell layer encircling the inner cell mass of the blastocyst. Critical gene families controlling these events include: the E-cadherin-catenin cell adhesion family, …
Trophectoderm Differentiation In The Bovine Embryo: Characterization Of A Polarized Epithelium., L C Barcroft, A Hay-Schmidt, A Caveney, E Gilfoyle, E W Overstrom, P Hyttel, A J Watson
Trophectoderm Differentiation In The Bovine Embryo: Characterization Of A Polarized Epithelium., L C Barcroft, A Hay-Schmidt, A Caveney, E Gilfoyle, E W Overstrom, P Hyttel, A J Watson
Obstetrics & Gynaecology Publications
Blastocytst formation is dependent on the differentiation of a transporting epithelium, the trophectoderm, which is coordinated by the embryonic expression and cell adhesive properties of E-cadherin. The trophectoderm shares differentiative characteristics with all epithelial tissues, including E-cadherin-mediated cell adhesion, tight junction formation, and polarized distribution of intramembrane proteins, including the Na-K ATPase. The present study was conducted to characterize the mRNA expression and distribution of polypeptides encoding E-cadherin, beta-catenin, and the tight junction associated protein, zonula occludens protein 1, in pre-attachment bovine embryos, in vitro. Immunocytochemistry and gene specific reverse transcription--polymerase chain reaction methods were used. Transcripts for E-cadherin and …
How To Make A Blastocyst., A J Watson, G M Kidder, G A Schultz
How To Make A Blastocyst., A J Watson, G M Kidder, G A Schultz
Obstetrics & Gynaecology Publications
Several of the new reproductive technologies have been cultivated from our current understanding of the genetic programming and cellular processes that are involved in the major morphogenetic events of mammalian preimplantation development. Research directed at characterizing the patterns of gene expression during early development has shown that the embryo is initially under maternal control and later superseded by new transcriptional activity provided by the activation of the embryonic genome. Several embryonic transcripts encoding: (i) growth factors, (ii) cell junctions, (iii) plasma membrane ion transporters, and (iv) cell adhesion molecules have been identified as contributing directly to the progression of the …