Medicine and Health Sciences Commons^™

Mitogen-Activated Protein Kinase (Mapk) Blockade Of Bovine Preimplantation Embryogenesis Requires Inhibition Of Both P38 And Extracellular Signal-Regulated Kinase (Erk) Pathways., Pavneesh Madan, Michele D Calder, Andrew J Watson

Obstetrics & Gynaecology Publications

Blastocyst formation, as a critical period during development, is an effective indicator of embryonic health and reproductive efficiency. Out of a number of mechanisms underlying blastocyst formation, highly conserved mitogen-activated protein kinase (MAPK) signaling has emerged as a major mechanism involved in regulating murine preimplantation embryo development. The objective of our study was to ascertain the role of MAPK signaling in regulating bovine development to the blastocyst stage. Using reverse transcriptase PCR and immunohistochemical staining procedures we have demonstrated that mRNA transcripts and polypeptides encoding p38 MAPK pathway constituents are detectable in preimplantation bovine embryos from the one-cell to the …

Investigating The Causes Of Low Birth Weight In Contrasting Ovine Paradigms., J M Wallace, Timothy Regnault, S W Limesand, W W Hay, R V Anthony

Paediatrics Publications

Intrauterine growth restriction (IUGR) still accounts for a large incidence of infant mortality and morbidity worldwide. Many of the circulatory and transport properties of the sheep placenta are similar to those of the human placenta and as such, the pregnant sheep offers an excellent model in which to study the development of IUGR. Two natural models of ovine IUGR are those of hyperthermic exposure during pregnancy, and adolescent overfeeding, also during pregnancy. Both models yield significantly reduced placental weights and an asymmetrically growth-restricted fetus, and display altered maternal hormone concentrations, indicative of an impaired trophoblast capacity. Additionally, impaired placental angiogenesis …

Neonatal Brain: Regional Variability Of In Vivo Mr Imaging Relaxation Rates At 3.0 T-Initial Experience, L. A. Williams, N. Gelman, P. A. Picot, D. S. Lee, J. R. Ewing, V. K. Han, R. T. Thompson

Anatomy and Cell Biology Publications

PURPOSE: To retrospectively investigate regional in vivo magnetic resonance,(MR). imaging transverse and longitudinal relaxation rates at 3.0 T in neonatal brain, the p relationship between these rates, and their potential use for gray matter (G),versus-M white matter (WM) tissue discrimination. MATERIALS AND METHODS: I Informed parental consent for performance of imaging procedures was obtained in each infant. Informed consent for retrospective image analysis was not required; ethics approval was obtained from institutional review board. At 3.0 T, R1 and R2 were measured in brain regions (frontal WM, posterior WM, periventricular WM, frontal GM, posterior GM, basal ganglia, and thalamus) in …

Glutamate Receptors In Perirhinal Cortex Mediate Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

Object recognition is consistently impaired in human amnesia and animal models thereof. Results from subjects with permanent brain damage have revealed the importance of the perirhinal cortex to object recognition memory. Here, we report evidence from rats for interdependent but distinct stages in object recognition memory (encoding, retrieval, and consolidation), which require glutamate receptor activity within perirhinal cortex. Transient blockade of AMPA receptor-mediated synaptic transmission within perirhinal cortex disrupted encoding for short- and long-term memory as well as retrieval and consolidation. In contrast, transient NMDA receptor blockade during encoding affected only long-term object recognition memory; NMDA receptor activity was also …

Effect Of Serum And Cumulus Cell Expansion On Marker Gene Transcripts In Bovine Cumulus-Oocyte Complexes During Maturation In Vitro., Michele D Calder, Anita N Caveney, Marc-Andre Sirard, Andrew J Watson

Obstetrics & Gynaecology Publications

OBJECTIVE: To determine the distribution of transcripts encoding the FSH receptor (FSHr), LH receptor (LHr), connexin 43 (Cx43), cyclooxygenase-2 (COX-2), and prostaglandin E(2) receptors 2 and 3 (EP2 and EP3) within bovine cumulus-oocyte complexes (COCs) and denuded oocytes and investigate the influence of gonadotropins, serum, and cumulus cell expansion on the abundance of transcripts encoding these genes.

DESIGN: Prospective controlled animal study.

SETTING: University research laboratory.

PATIENT(S): Animal models for human studies.

INTERVENTION(S): Cumulus-oocyte complexes were treated in culture with serum and gonadotropin-supplemented media to examine the effects to mRNA transcript levels.

MAIN OUTCOME MEASURE(S): Variation in mRNA transcript levels. …

Stage At Diagnosis And Cancer Survival For Indigenous Australians In The Northern Territory, John R. Condon, Tony Barnes, Bruce K. Armstrong, Sid Selva-Nayagam, J. Mark Elwood

Aboriginal Policy Research Consortium International (APRCi)

Objective: To investigate whether Indigenous Australians with cancer have more advanced disease at diagnosis than other Australians, and whether late diagnosis explains lower Indigenous cancer survival rates. Design: Retrospective cohort study.

Setting and participants: Indigenous and non-Indigenous people diagnosed with cancers of the colon and rectum, lung, breast or cervix and non-Hodgkin lymphoma in the Northern Territory of Australia in 1991–2000. Main outcome measures: SEER summary stage of cancer at diagnosis (local, regional or distant spread), cause-specific cancer survival rates and relative risk of cancer death.

Results: Diagnosis with advanced disease (regional or distant spread) was more common for Indigenous …

Learning To Like: A Role For Human Orbitofrontal Cortex In Conditioned Reward, Sylvia M L Cox, Alexandre Andrade, Ingrid Johnsrude

Brain and Mind Institute Researchers' Publications

A great deal of human behavior and motivation is based on the intrinsic emotional significance of rewarding or aversive events, as well as on the associations formed between such emotional events and concurrent environmental stimuli. Recent functional neuroimaging studies have implicated the ventral striatum, orbitofrontal cortex (OFC), and amygdala in the representation of reward values and/or in the anticipation of rewarding events. Here, we use functional magnetic resonance imaging to compare brain activation during the presentation of reward with that during presentation of (conditioned) stimuli that have been paired previously with reward. Specifically, we aimed to investigate conditioned reward in …

A Contralateral Preference In The Lateral Occipital Area: Sensory And Attentional Mechanisms., Matthias Niemeier, Herbert C Goltz, Anil Kuchinad, Douglas B Tweed, Tutis Vilis

Brain and Mind Institute Researchers' Publications

Here we examined the level of the lateral occipital (LO) area within the processing stream of the ventral visual cortex. An important determinant of an area's level of processing is whether it codes visual elements on both sides of the visual field, as do higher visual areas, or prefers those in the contralateral visual field, as do early visual areas. The former would suggest that LO, on one side, combines bilateral visual elements into a whole, while the latter suggests that it codes only the parts of forms. We showed that LO has a relative preference for visual objects in …

Transient Inactivation Of Perirhinal Cortex Disrupts Encoding, Retrieval, And Consolidation Of Object Recognition Memory., Boyer D Winters, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

Damage to perirhinal cortex (PRh) impairs object recognition memory in humans, monkeys, and rats when tested in tasks such as delayed nonmatching to sample, visual paired comparison, and its rodent analog, the spontaneous object recognition task. In the present study, we have capitalized on the discrete one-trial nature of the spontaneous object recognition task to investigate the role of PRh in several distinct stages of object recognition memory. In a series of experiments, transient inactivation of PRh was accomplished with bilateral infusions of lidocaine directly into PRh immediately before the sample phase (encoding), immediately before the choice phase (retrieval), or …

Inhibiting Gene Expression At Transcription Start Sites In Chromosomal Dna With Antigene Rnas, Daniel Hardy

Data and Test Instruments

No abstract provided.

Modification Of Xenoantigens On Porcine Erythrocytes For Xenotransfusion, Jay Doucet

Data and Test Instruments

Removal of cell membrane α-gal(1–3)β-galGlcNac epitopes (called α-gal) by chemical and enzymatic methods and chemical masking of other xenoantigens was performed to examine the impact on porcine erythrocyte (PRBC) antigenicity for xenotransfusion.PRBCs were subjected to removal of membrane α-gal with α-galactosidase, covalent attachment of cyanuric acid-linked methoxypolyethylene glycol (PEGylation), or both. PRBC integrity was assessed by light and electron microscopy, osmotic fragility, and determination of p50. Effects of treatment were measured by hemagglutination, complement fixation, flow cytometric assay of IgG/M binding, cross-match testing to human sera and51Cr red cell survival in mice.PEGylation reduced hemagglutination titers moderately, although α-galactosidase treatment reduced …

Extended Vs. Small Field Irradiation In High Risk Post Esophagectomy Patients Receiving Combined Chemoradiation Therapy: A Decade Experience In Treatment Of Esophageal Cancer, Edward Yu, Patricia Tai, George Rodrigues, Robert Ash, Larry Stitt, Rashid A. Dar, Pauline Truong, Gregory M. Videtic, Richard Malthaner, Richard Inculet, Anna Tomiak, Jawaid Younus, Brian Dingle, Walter Kocha, Mark Vincent

Oncology Presentations

OBJECTIVE: To assess the impact of extended field irradiation with anastomotic coverage on local recurrence in high risk resected esophageal cancerpatients.

METHODS: From 1989-1999, high risk resected esophageal cancer cases receiving post-resection chemoradiation were reviewed. Adjuvant chemotherapy consisted of four cycles of fluorouracil-based regimens. Loco-regional irradiation with or without coverage of anastomotic site had radiation a dose range from 45-60 Gyat 1.8-2.0 Gy/fraction given with initial anterior-posterior/posterior-anterior arrangement with either extended (with anastomotic coverage), or small (without anastomotic coverage) field followed by oblique fields for boost.

RESULTS: One hundred eighty-eight charts were reviewed. Seventy-two patients were eligible for post-resection chemoradiation. …

Robot Assisted Ultrasound Imaged Guided Interstitial Lung Brachytherapy In A Porcine Model, Richard A. Malthaner, Edward Yu, Jerry J. Battista, Chris Blake, Donal Downey, Aaron Fenster

Oncology Presentations

We set out to see if permanent interstitial brachytherapy seeds could be safely and reproducibly inserted thoracoscopicaly with the ZEUS Robotic system and intraoperative ultrasound into in-vivo porcine lungs.

Uwomj Volume 74, No. 1, Western University

University of Western Ontario Medical Journal

Schulich School of Medicine & Dentistry

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 …

Treatment Patterns For Cancer In Western Australia: Does Being Indigenous Make A Difference?, Sonja E. Hall, Caroline E. Bulsara, Max K. Bulsara, Timothy G. Leahy, Margaret R. Culbong, Delia Hendrie, C D'Arcy J. Holman

Aboriginal Policy Research Consortium International (APRCi)

Objective: To examine whether hospital patients with cancer who were identified as Indigenous were as likely to receive surgery for the cancer as non-Indigenous patients. Design, setting and patients: Epidemiological survey of all Western Australian (WA) patients who had a cancer registration in the state-based WA Record Linkage Project that mentioned cancer of the breast (1982–2000) or cancer of the lung or prostate (1982–2001).

Main outcome measures: The likelihoods of receiving breast-conserving surgery or mastectomy for breast cancer, lung surgery for lung cancer, or radical or non-radical prostatectomy for prostate cancer were compared between the Indigenous and non-Indigenous populations using …

Living Donor Liver Transplantation: Surgical Techniques And Innovations, Vivian Mcalister

Data and Test Instruments

A colleague and I attended a talk about a set of liver transplant experiments in mice, which the speaker had designed to undermine a commonly held immunological belief. My companion (who should have known better) afterward asked me rhetorically, "What's next? Heart transplantation in a tadpole?"When does the awe-inspiring give way to the commonplace? Technically wonderful surgery is considered ordinary not because it is commonly done but because the holder of this opinion has no image of the technique.Not long ago, resectional hepatic surgery was followed by the development of orthotopic liver transplantation. Although both techniques have matured into conventional …

Health Care In Canada: Provinces Versus The Federal Government, Vivian Mcalister

Data and Test Instruments

Transcript: Listen to today's Commentary Introduction: Who speaks best for health care: Paul Martin or the provincial premiers? Vivian McAlister is a transplant surgeon and a professor of surgery in London, Ontario. On Commentary, he says move over Ottawa..the provinces should take the lead in improving medicare. Vivian McAlister: During last month's election campaign Paul Martin set himself up as the saviour of medicare. He was reinforcing an old theme: that Ottawa must keep a close eye on the provinces lest they experiment - looking for different ways to provide health care. The prime minister conveniently ignored the fact that …

Individual And Regional Determinants Of Mammography Uptake, Anita Kothari, Stephen Birch

Health Studies Publications

Background: Analysis of mammography utilization has traditionally been performed from an individual-level perspective. The purpose of this study was to explore the combined influence of individual- and regional-level determinants of mammography utilization.

Methods: Logistic hierarchical multilevel modelling was used to investigate the influences of region of residence and individual characteristics on mammography utilization. Socioeconomic status information about health planning regions was derived from the 1996 Canadian Census. Individual-level information was extracted from the 1996 National Population Health Survey.

Results: After controlling for individual-level education, regions with fewer high school graduates had lower levels of mammography utilization. A cross-level interaction between …

Double Dissociation Between The Effects Of Peri-Postrhinal Cortex And Hippocampal Lesions On Tests Of Object Recognition And Spatial Memory: Heterogeneity Of Function Within The Temporal Lobe., Boyer D Winters, Suzanna E Forwood, Rosemary A Cowell, Lisa M Saksida, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

It is widely believed that declarative memory is mediated by a medial temporal lobe memory system consisting of several distinct structures, including the hippocampus and perirhinal cortex. The strong version of this view assumes a high degree of functional homogeneity and serial organization within the medial temporal lobe, such that double dissociations between individual structures should not be possible. In the present study, we tested for a functional double dissociation between the hippocampus and peri-postrhinal cortex in a single experiment. Rats with bilateral excitotoxic lesions of either the hippocampus or peri-postrhinal cortex were assessed in tests of spatial memory (radial …

Deletion Of The Na/K-Atpase Alpha1-Subunit Gene (Atp1a1) Does Not Prevent Cavitation Of The Preimplantation Mouse Embryo., L C Barcroft, A E Moseley, J B Lingrel, A J Watson

Obstetrics & Gynaecology Publications

Increases in Na/K-ATPase activity occur concurrently with the onset of cavitation and are associated with increases in Na(+)-pump subunit mRNA and protein expression. We have hypothesized that the alpha1-isozyme of the Na/K-ATPase is required to mediate blastocyst formation. We have tested this hypothesis by characterizing preimplantation development in mice with a targeted disruption of the Na/K-ATPase alpha1-subunit (Atp1a1) using embryos acquired from matings between Atp1a1 heterozygous mice. Mouse embryos homozygous for a null mutation in the Na/K-ATPase alpha1-subunit gene are able to undergo compaction and cavitation. These findings demonstrate that trophectoderm transport mechanisms are maintained in the absence of the …

Transplant First

Data and Test Instruments

No abstract provided.

P38 Mapk Signaling During Murine Preimplantation Development., David R Natale, Andrew J M Paliga, Frank Beier, S J A D'Souza, Andrew J Watson

Obstetrics & Gynaecology Publications

Mitogen-activated protein kinase (MAPK) pathways mediate some important cellular processes and are likely to also regulate preimplantation development. The role of p38 MAP kinase signaling during murine preimplantation development was investigated in the present study. p38 MAPK, p38-regulated or -activated kinase (PRAK; MK5), map kinase-activated protein kinase 2 (MK2), and heat shock protein 25 (hsp25) mRNAs and proteins were detected throughout preimplantation development. Two-cell stage embryos cultured in the presence of SB220025 and SB203580 (specific inhibitors of p38 MAPK alpha/beta), progressed to the eight-cell stage with the same frequency as controls; however, treated embryos halted their development at the 8- …

Somatotopic Representation Of Action Words In Human Motor And Premotor Cortex, Olaf Hauk, Ingrid Johnsrude, Friedemann Pulvermüller

Brain and Mind Institute Researchers' Publications

Since the early days of research into language and the brain, word meaning was assumed to be processed in specific brain regions, which most modern neuroscientists localize to the left temporal lobe. Here we use event-related fMRI to show that action words referring to face, arm, or leg actions (e.g., to lick, pick, or kick), when presented in a passive reading task, differentially activated areas along the motor strip that either were directly adjacent to or overlapped with areas activated by actual movement of the tongue, fingers, or feet. These results demonstrate that the referential meaning of action words has …

Uwomj Volume 73, No. 1, 2004, Western University

University of Western Ontario Medical Journal

Schulich School of Medicine & Dentistry

Characteristics Of Aboriginal Injecting Drug Users In Sydney, Australia: Prison History, Hepatitis C Status And Drug Treatment Experiences, Carolyn Day, Joanne Ross, Kate Dolan

Aboriginal Policy Research Consortium International (APRCi)

Australian Aboriginals are overrepresented in prisons and tend to be overrepresented in studies of injecting drug users (IDU). The aim of this study was to examine differences between Aboriginal and non-Aboriginal IDUs in terms of gender, prison history and hepatitis C status and testing. Secondary analyses were conducted on data from three cross-sectional studies of IDUs. These studies employed similar methodologies, with recruitment being through needle and syringe programs, methadone clinics, snowballing and street intercepts. All studies were coordinated through the National Drug and Alcohol Research Centre. Aboriginal people were overrepresented in all studies, were more likely to have been …

Living Donor Liver Transplantation: Surgical Techniques And Innovations By Koichi Tanaka, Yukihiro Inomaka, And Satoshi Kaihara, Vivian Mcalister

Data and Test Instruments

Living-donor liver transplantation combines the techniques of hepatic resection and transplantation. The principal difference between living donation of liver and resection is the absolute requirement in the former to maintain the integrity of the liver on each side of the dividing line. To do this, the surgeon must retain the vascular supply and drainage of both sides throughout the dissection, up to the moment of graft removal. In this book, Tanaka and colleagues take us through the surgery in a manner that is at once detailed and exciting, through the generous use of magnificent electronic photography.

Review Of Surgical Limits: The Life Of Gordon Murray By Shelly Mckellar, Vivian Mcalister

Data and Test Instruments

Gordon Murray ranks as Canada’s greatest surgical pioneer, to whom history has been most unkind. Shelley McKellar has written a surgical biography that goes a long way toward explaining how this came about, and gives us a good opportunity to reassess Murray’s extraordinary career.

A Null Mutation For Tissue Inhibitor Of Metalloproteinases-3 (Timp-3) Impairs Murine Bronchiole Branching Morphogenesis., Sean E Gill, M Cynthia Pape, Rama Khokha, Andrew J Watson, Kevin J Leco

Obstetrics & Gynaecology Publications

Tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) degradation by matrix metalloproteinases (MMPs). We have examined the role of TIMP-3 on ECM homeostasis and bronchiole branching morphogenesis during murine embryogenesis. Employing an in vitro organ culture system, we found decreased bronchiolar branching in null lungs when compared with wild type (WT) counterparts after 2 days in culture. When a synthetic inhibitor of MMPs at low dose was added to the culture system, branching was augmented regardless of genotype. Gelatin and in situ zymography revealed that null lungs exhibited enhanced activation of MMPs throughout lung development. We analysed the impact …

Seek And Ye Shall Find, Vivian Mcalister

Data and Test Instruments

The United States has relaxed its ban on the importation of Canadian meat cuts from cattle less than 30 months of age. Mexico, too, is reopening its borders to Canadian beef.The principal argument Canada has used to reassure its trading partners is that only one older cow, and none of the 2,700 animals with which that cow came into contact, tested positive for mad-cow disease. Meanwhile, the Canadian Food Inspection Agency has detailed measures it is taking to prevent mad-cow disease, or bovine spongiform encephalopathy, "from entering Canada." Surveillance and testing of animals has been increased.But it's folly to try …