Medicine and Health Sciences Commons^™

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. …

The Effects Of Field-Of-View And Patient Size On Ct Numbers From Cone-Beam Computed Tomography., Katrina Y T Seet, Arvand Barghi, Slav Yartsev, Jacob Van Dyk

Oncology Publications

Cone-beam computed tomography (CBCT) is used for patient alignment before treatment and is ideal for use in adaptive radiotherapy to account for tumor shrinkage, organ deformation and weight loss. However, CBCT images are prone to artifacts such as streaking and cupping effects, reducing image quality and CT number accuracy. Our goal was to determine the optimum combination of cone-beam imaging options to increase the accuracy of image CT numbers. Several phantoms with and without inserts of known relative electron densities were imaged using the Varian on-board imaging system. It was found that CT numbers are most influenced by the selection …

What Factors Predict Outcome At Relapse After Previous Esophagectomy And Adjuvant Therapy In High-Risk Esophageal Cancer?, Edward Yu, Patricia Tai, Richard Malthaner, Larry Stitt, George Rodrigues, Rashid Dar, Brian Yaremko, Jawaid Younus, Michael Sanatani, Mark Vincent, Brian Dingle, Dalilah Fortin, Richard Inculet

Oncology Presentations

Management of patients who have disease relapse after completion of surgery and adjuvant chemo-radiation (CRT) is controversial.

Some oncologists would advocate intensive therapeutic intervention due to promising experience on treatment for recurrence disease while others would recommend palliative support due to the concerns for poor patient outcome post disease recurrence.

In Addition, it is not clear if patient outcome is improved post adjuvant CRT when patients at risk have resection margin involvement and if time interval to recurrence can affect patient survival post relapse.

The present study was conducted to determine what factors will affect patient outcome at relapse after …

Effects Of Genistein Following Fractionated Lung Irradiation In Mice., Andrea E Para, Andrea Bezjak, Ivan W T Yeung, Jacob Van Dyk, Richard P Hill

Oncology Publications

BACKGROUND AND PURPOSE: This study investigated protection of lung injury by genistein following fractionated doses of radiation and its effect on tumor response.

MATERIAL AND METHODS: C3H/HeJ mice were irradiated (100 kVp X-rays) with 9 fractions of 3.1 Gy over 30 days (approximately equivalent to 10 Gy single dose) and were maintained on a genistein diet ( approximately 10mg/kg). Damage was assessed over 28 weeks in lung cells by a cytokinesis block micronucleus (MN) assay and by changes in breathing rate and histology. Tumor protection was assessed using a colony assay to determine cell survival following in situ irradiation of …

Intrauterine Growth Restriction Increases Fetal Hepatic Gluconeogenic Capacity And Reduces Messenger Ribonucleic Acid Translation Initiation And Nutrient Sensing In Fetal Liver And Skeletal Muscle., Stephanie R Thorn, Timothy Regnault, Laura D Brown, Paul J Rozance, Jane Keng, Michael Roper, Randall B Wilkening, William W Hay, Jacob E Friedman

Paediatrics Publications

Expression of key metabolic genes and proteins involved in mRNA translation, energy sensing, and glucose metabolism in liver and skeletal muscle were investigated in a late-gestation fetal sheep model of placental insufficiency intrauterine growth restriction (PI-IUGR). PI-IUGR fetuses weighed 55% less; had reduced oxygen, glucose, isoleucine, insulin, and IGF-I levels; and had 40% reduction in net branched chain amino acid uptake. In PI-IUGR skeletal muscle, levels of insulin receptor were increased 80%, whereas phosphoinositide-3 kinase (p85) and protein kinase B (AKT2) were reduced by 40%. Expression of eukaryotic initiation factor-4e was reduced 45% in liver, suggesting a unique mechanism limiting …

Switching And Selecting Atypical Antipsychotic Drugs: Quetiapine, Amresh Srivastava

Psychiatry Presentations

No abstract provided.

Mitogen-Activated Protein Kinase (Mapk) Pathways Mediate Embryonic Responses To Culture Medium Osmolarity By Regulating Aquaporin 3 And 9 Expression And Localization, As Well As Embryonic Apoptosis., Christine E Bell, Nathalie M K Larivière, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

BACKGROUND: In order to advance the development of culture conditions and increase the potential for supporting normal preimplantation embryo development in vitro, it is critical to define the mechanisms that early embryos utilize to survive in culture. We investigated the mechanisms that embryos employ in response to culture medium osmolarity. We hypothesized that mitogen-activated protein kinase (MAPK) pathways mediate responses to hyperosmotic stress by regulating Aquaporin (AQP) 3 and 9 expression as well as embryonic apoptosis.

METHODS: Real-time reverse transcription and polymerase chain reaction and whole-mount immunofluorescence were used to determine the relative mRNA levels and protein localization patterns of …

A Dominant Loss-Of-Function Gja1 (Cx43) Mutant Impairs Parturition In The Mouse, Dan Tong, Xuerong Lu, Hong-Xing Wang, Isabelle Plante, Ed Lui, Dale W. Laird, Donglin Bai, Gerald M. Kidder

Physiology and Pharmacology Publications

Expression of GJA1 (commonly known as connexin43 or Cx43), a major myometrial gap junction protein, is upregulated before the onset of delivery, suggesting an essential role for Cx43-mediated gap junctional intercellular communication (GJIC) in normal uterine contraction during parturition. To determine how a disease-linked Cx43 mutation affects myometrial function, we studied a mutant mouse model carrying an autosomal dominant mutation (Gja1Jrt) in the gene encoding Cx43 that displays features of the human genetic disease oculodentodigital dysplasia. We found that Cx43 level, specifically the phosphorylated species of the protein, is significantly reduced in the myometrium of the mutant mice (Gja1Jrt/+), as …

Clinical Field-Strength Mri Of Amyloid Plaques Induced By Low-Level Cholesterol Feeding In Rabbits, John A. Ronald, Yuanxin Chen, Lisa Bernas, Hagen H. Kitzler, Kem A. Rogers, Robert A. Hegele, Brian K. Rutt

Robarts Imaging Publications

Two significant barriers have limited the development of effective treatment of Alzheimer’s disease. First, for many cases the aetiology is unknown and likely multi-factorial. Among these factors, hypercholesterolemia is a known risk predictor and has been linked to the formation of b-amyloid plaques, a pathological hallmark this disease. Second, standardized diagnostic tools are unable to definitively diagnose this disease prior to death; hence new diagnostic tools are urgently needed. Magnetic resonance imaging (MRI) using high field-strength scanners has shown promise for direct visualization of b-amyloid plaques, allowing in vivo longitudinal tracking of disease progression in mouse models. Here, we present …

Oogenesis Defects In A Mutant Mouse Model Of Oculodentodigital Dysplasia, Dan Tong, Deanne Colley, Renee Thoo, Tony Y. Li, Isabelle Plante, Dale W. Laird, Donglin Bai, Gerald M. Kidder

Physiology and Pharmacology Publications

The essential role of connexin43 (Cx43) during oogenesis has been demonstrated by the severe germ cell deficiency and arrested folliculogenesis observed in Cx43 knockout mice. Recently, another mutant mouse strain became available (Gja1Jrt/+) that carries the dominant loss-of-function Cx43 mutation, Cx43G60S. Gja1Jrt/+ mice display features of the human disease, oculodentodigital dysplasia (ODDD), caused by mutations in the GJA1 gene. We have used this new mutant strain to study how a disease-linked Cx43 mutant affects oogenesis. We found that female mutant mice are subfertile with significantly reduced mating success and small litters. The phosphorylated species of the Cx43 protein are reduced …

Snai1 And Snai2 Are Asymmetrically Expressed At The 2-Cell Stage And Become Segregated To The Te In The Mouse Blastocyst., Christine E Bell, Andrew J Watson

Obstetrics & Gynaecology Publications

SNAI1 and SNAI2 are transcription factors that initiate Epithelial-to-Mesenchymal cell transitions throughout development and in cancer metastasis. Here we show novel expression of SNAI1 and SNAI2 throughout mouse preimplantation development revealing asymmetrical localization of both SNAI1 and SNAI2 in individual blastomeres beginning at the 2-cell stage through to the 8-cell stage where SNAI1 and SNAI2 are then only detected in outer cells and not inner cells of the blastocyst. This study implicates SNAI1 and SNAI2 in the lineage segregation of the trophectoderm and inner cell mass, and provides new insight into these oncogenes.

Indications For Resection Of Metastatic Liver Lesions, Vivian Mcalister

Surgery Presentations

No abstract provided.

Pancreatic Cancer: Define Unresectable, Vivian Mcalister

Surgery Presentations

No abstract provided.

Grasping And Lifting Different Materials, Gavin Buckingham, Jonathan S. Cant, Melvyn A. Goodale

Psychology Presentations

The material from which an object is made can determine how heavy it feels (Seashore, 1899). Interestingly, a metal block that has been adjusted to have the same size and mass as a polystyrene block will feel lighter than the polystyrene block. We recently showed that participants experiencing this material-weight illusion’ (MWI) do not apply forces that match their perceptual experience of heaviness ‐ just like in the size‐weight illusion ( Flanagan & Beltzner, 2000).

Our previous study showed that forces on early trials were scaled to each participant’s expectations of how much a particular block should weigh ‐ excessive …

A Dissociation Between Perception And Action In The Material‐Weight Illusion, Gavin Buckingham, Jonathan S. Cant, Kai-Ling C. Kao, Melvyn A. Goodale

Psychology Presentations

We examined what forces are applied to objects that elicit this illusion when they are lifted.We predicted that:

(1) Forces on early trials will scale to each participant’s expectations of how much a particular block will weigh ‐ excessive force will be applied to the metal block and insufficient force applied to the polystyrene block.

(2) Forces on later trials will scale to the real weight of each block ‐ identical levels of force applied to all the blocks.

(3) MWI will persist throughout ‐ polystyrene block will feel the heaviest, metal block will feel the lightest.

Adaptive Radiation Therapy For Localized Mesothelioma With Mediastinal Metastasis Using Helical Tomotherapy., James Renaud, Slav Yartsev, A Rashid Dar, Jacob Van Dyk

Oncology Publications

The purpose of this study was to compare 2 adaptive radiotherapy strategies with helical tomotherapy. A patient having mesothelioma with mediastinal nodes was treated using helical tomotherapy with pretreatment megavoltage CT (MVCT) imaging. Gross tumor volumes (GTVs) were outlined on every MVCT study. Two alternatives for adapting the treatment were investigated: (1) keeping the prescribed dose to the targets while reducing the dose to the OARs and (2) escalating the target dose while maintaining the original level of healthy tissue sparing. Intensity modulated radiotherapy (step-and-shoot IMRT) and 3D conformal radiotherapy (3DCRT) plans for the patient were generated and compared. The …

Identification Of Wnt/Β-Catenin Signaling Pathway Components In Human Cumulus Cells, Hong-Xing Wang, Francis R. Tekpetey, Gerald M. Kidder

Physiology and Pharmacology Publications

Signaling via the conserved WNT/β-CATENIN pathway controls diverse developmental processes. To explore its potential role in the ovary, we investigated the expression of WNTs, frizzled (FZD) receptors and other pathway components in human cumulus cells obtained from oocytes collected for in vitro fertilization. Proteins were detected in cultured cells using immunofluorescence microscopy. Protein–protein interactions were analyzed by means of immunoprecipitation. WNT2, FZD2, FZD3 and FZD9 were identified but WNT1, WNT4 and FZD4 were not detected. WNT2 is co-expressed with FZD2, FZD3 and FZD9. Co-immunoprecipitation using WNT2 antibody demonstrated that WNT2 interacts with both FZD3 and FZD9, but only FZD9 antibody …