26 results match your criteria: "Loeb Health Research Institute at the Ottawa Hospital[Affiliation]"

The immunogenicity of DNA vaccines is due in part to the presence of stimulatory CpG motifs, which may actually be essential to their function. CpG motifs are unmethylated cytosine-guanine dinucleotides within a certain flanking base context and such sequences are commonly found in bacterial but not mammalian DNA. It appears that through evolutionary adaptation, the vertebrate immune system developed the ability to recognize these sequences as a "danger signal" and respond by rapid activation of the innate immune system.

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Development and evaluation of a decision aid for patients with stage IV non-small cell lung cancer.

Health Expect

June 2000

Sisters of Charity of Ottawa Health Service, Ottawa, Canada; Ottawa Hospital-Civic Campus, Ottawa, Canada; University of Ottawa, Ottawa, Canada; Clinical Epidemiology Unit, Loeb Health Research Institute at the Ottawa Hospital-Civic Campus, Ottawa, Canada; Ottawa Regional Cancer Centre, Ottawa, Canada; Ottawa Regional Women's Breast Health Centre, Ottawa Hospital-Civic Campus, Ottawa, Canada.

Although guidelines for treating stage IV non-small cell lung cancer suggest that the patient's values should be considered in decision-making, there are no practical tools available to assist them with their decision-making. OBJECTIVE: To develop and evaluate a decision aid that incorporates patient values. DESIGN AND SAMPLE: (1) Before/after evaluation with patients referred to a regional cancer centre.

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The binding of Ku antigen to homeodomain proteins promotes their phosphorylation by DNA-dependent protein kinase.

J Biol Chem

May 2001

Department of Medicine, The Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Ottawa, Ontario K1Y 4E9, Canada.

The Ku antigen (70- and 80-kDa subunits) is a regulatory subunit of DNA-dependent protein kinase (DNA-PK) that promotes the recruitment of the catalytic subunit of DNA-PK (DNA-PKcs) to DNA ends and to specific DNA sequences from which the kinase is activated. Ku and DNA-PKcs plays essential roles in double-stranded DNA break repair and V(D)J recombination and have been implicated in the regulation of specific gene transcription. In a yeast two-hybrid screen of a Jurkat T cell cDNA library, we have identified a specific interaction between the 70-kDa subunit of Ku heterodimer and the homeodomain of HOXC4, a homeodomain protein expressed in the hematopoietic system.

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Synthetic oligodeoxynucleotides (ODN) containing immunostimulatory CpG motifs (CpG ODN) are potent adjuvants in mice when delivered by parenteral (intramuscular, subcutaneous) and mucosal (intranasal, oral and intrarectal) routes. We have recently shown that with mucosal delivery non-CpG ODN can also have immunostimulatory properties which, in contrast to the Th1-bias characteristic of CpG ODN, are predominantly Th2-like. Herein, using hepatitis B surface antigen (HBsAg) and tetanus toxoid (TT) as model antigens in BALB/c mice, we have examined a number of different ODN (CpG, non-CpG, poly-T, poly-CG) to determine their effects on immune responses after mucosal (oral) and parenteral (IM) immunizations.

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DNA immunization is a relatively new vaccination strategy that involves the direct introduction into the host of plasmid DNA encoding the desired antigen. The DNA enters host cells and results in immune responses following in vivo expression of the antigen. Although DNA-based immunization works well in animal models for the induction of both humoral and cell-mediated immune responses, its success in humans has been limited.

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The testicular germ-cell protease PC4 is also expressed in macrophage-like cells of the ovary.

J Reprod Immunol

February 2001

Molecular Medicine and Diseases of Aging Center, The Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Ont., KIY 4E9, Canada.

PC4 is a serine protease primarily expressed in spermatids. We have produced PC4-deficient mice carrying an insertion of the bacterial gene for beta galactosidase under the PC4 gene promoter. Male mice lacking PC4 (-/-) exhibit severely reduced fertility.

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Glucocorticoid receptor homodimers and glucocorticoid-mineralocorticoid receptor heterodimers form in the cytoplasm through alternative dimerization interfaces.

Mol Cell Biol

February 2001

Department of Graduate Program in Biochemistry, The Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada K1Y 4E9.

Steroid hormone receptors act to regulate specific gene transcription primarily as steroid-specific dimers bound to palindromic DNA response elements. DNA-dependent dimerization contacts mediated between the receptor DNA binding domains stabilize DNA binding. Additionally, some steroid receptors dimerize prior to their arrival on DNA through interactions mediated through the receptor ligand binding domain.

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Adipose cell apoptosis: death in the energy depot.

Int J Obes Relat Metab Disord

November 2000

Department of Medicine and Biochemistry, Microbiology and Immunology, Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Canada.

Apoptosis is critical for mammalian tissue homeostasis, and its disruption has been linked to a wide variety of disorders, including cancer, neurodegenerative disease, autoimmune disease and diabetes. This review will focus on recent investigations that have begun to address the potential role of apoptosis in adipose tissue growth. Evidence for apoptosis occurring in mature adipocytes has been obtained through the use of in vitro cell culture models as well as in vivo studies in rodents and humans.

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We have previously reported that synthetic oligodeoxynucleotides containing immunostimulatory CpG motifs (CpG ODN) are potent adjuvants to protein administered by intramuscular (IM) injection or intranasal (IN) inhalation to BALB/c mice. Herein, we have evaluated oral delivery of CpG ODN with purified hepatitis B surface antigen (HBsAg) or tetanus toxoid (TT) to determine its potential as an adjuvant to oral vaccines. CpG ODN augmented systemic (IgG in plasma, CTL, T-cell proliferation) and mucosal (IgA in lung, vaginal or gut washes, feces and saliva) immune responses against both antigens.

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Distal-less-related homeobox genes of vertebrates: evolution, function, and regulation.

Biochem Cell Biol

April 2001

Loeb Health Research Institute at the Ottawa Hospital, Dept. of Medicine, University of Ottawa, ON, Canada.

Homeobox genes of the Distal-less family have been identified in virtually all metazoan groups where they play roles in the ontogeny of these animals. The vertebrate Distal-less related genes (Dlx genes) are thought to have arisen as a result of a tandem gene duplication event followed by a number of larger genomic scale duplications and thus represent an interesting model with which to study the evolution of clustered gene families. Dlx genes are involved in the development of the forebrain, branchial arches, sensory organs, and limbs.

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Dlx homeobox genes of vertebrates are often organised as physically linked pairs in which the two genes are transcribed convergently (tail-to-tail arrangement). Three such Dlx pairs have been found in mouse, human, and zebrafish and are thought to have originated from the duplication of an ancestral gene pair. These pairs include Dlx1/Dlx2, Dlx7/Dlx3, and Dlx6/Dlx5 (the zebrafish orthologue of Dlx5 is named dlx4).

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We have previously demonstrated that synthetic oligodeoxynucleotides (ODN) containing immunostimulatory CpG motifs (CpG ODN) are potent adjuvants in mice when delivered by intramuscular, intranasal and subcutaneous routes. Herein, using tetanus toxoid (TT) as a model antigen in BALB/c mice, we compared the ability of CpG ODN to induce mucosal and systemic humoral immune responses when antigen was delivered by three different routes: intrarectal, intranasal and oral. Results showed differences in immune responses with the three routes and also revealed that non-CpG "control" ODN had adjuvant effects when used at mucosal sites.

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Chemokines, in addition to their characterized functions as immune modulators, also play a role in developmental processes such as neural cell migration. Although, chemokines have been described in human, mouse and other vertebrate species, they have yet to be characterized in zebrafish. In this paper, we report the isolation and expression analysis of scyba, a zebrafish gene encoding a CXC-type chemokine protein.

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Application of DNA vaccine technology to aquaculture.

Adv Drug Deliv Rev

September 2000

Loeb Health Research Institute at the Ottawa Hospital, 725 Parkdale Avenue, Ottawa, Ontario, Canada K1Y 4E9.

The aquaculture industry needs to augment its global production and efficiency to meet the increasing consumer needs for fish and shellfish products. Unfortunately, infectious diseases have been a major impediment to the development and profitability of fish farms. While vaccines offer the most efficient way to control infectious pathogens, current products have only been successful against some diseases.

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One of the most exciting developments in the field of vaccine research in recent years has been DNA vaccines, with which immune responses are induced subsequent to the in vivo expression of antigen from directly introduced plasmid DNA. Strong immune responses have been demonstrated in a number of animal models against many viral, bacterial and parasitic pathogens, and several human clinical trials have been undertaken. The strong and long-lasting antigen-specific humoral (antibodies) and cell-mediated (T help, other cytokine functions and cytotoxic T cells) immune responses induced by DNA vaccines appear to be due to the sustained in vivo expression of antigen, efficient antigen presentation and the presence of stimulatory CpG motifs.

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Functional TSH receptor in human abdominal preadipocytes and orbital fibroblasts.

Am J Physiol Cell Physiol

August 2000

Departments of Medicine and Biochemistry, Microbiology, and Immunology, Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Canada.

Controversy continues about whether, and to what levels of abundance, thyroid-stimulating hormone receptors (TSHR) are found in human tissues other than the thyroid gland. Restricted expression to the thyroid and orbit would suggest that TSHR represents the target autoantigen in thyroid-associated ophthalmopathy. A more generalized pattern of tissue expression would be inconsistent with TSHR acting as the autoantigen that is solely responsible for selectively targeting the immune system to the orbit.

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Oligonucleotides containing immunostimulatory CpG motifs (CpG ODN) have been shown to be potent Th1-type adjuvants for augmenting antigen-specific responses in mice against hepatitis B surface antigen (HBsAg). The hepatitis B virus (HBV) infects only humans and great apes and appears to exist among wild chimpanzees and orangutans. An outbreak of HBV among orangutans being rehabilitated for re-introduction to the jungle caused the death of several animals.

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The ability to augment protective immune responses with minimal side effects is quintessential for a good adjuvant. This study has compared various adjuvants that are used in animal research (Freund's complete and incomplete adjuvants, Titermax Gold), are licensed for human use (alum), or are in clinical testing for humans (monophosphoryl lipid, CpG DNA), for their ability to augment humoral responses to a model antigen (hepatitis B surface antigen) and for the degree of damage they caused in the injected muscle. According to the data, the adjuvant combination CpG DNA+alum had the greatest potential to augment immune responses with minimal side effects at the injection site.

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A highly conserved enhancer in the Dlx5/Dlx6 intergenic region is the site of cross-regulatory interactions between Dlx genes in the embryonic forebrain.

J Neurosci

January 2000

Loeb Health Research Institute at the Ottawa Hospital and Department of Medicine, University of Ottawa, Ottawa, Ontario K1Y 4E9, Canada.

Four Dlx homeobox genes, Dlx1, Dlx2, Dlx5, and Dlx6 are expressed in the same primordia of the mouse forebrain with temporally overlapping patterns. The four genes are organized as two tail-to-tail pairs, Dlx1/Dlx2 and Dlx5/Dlx6, a genomic arrangement conserved in distantly related vertebrates like zebrafish. The Dlx5/Dlx6 intergenic region contains two sequences of a few hundred base pairs, remarkably well conserved between mouse and zebrafish.

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DNA vaccines can induce potent humoral and cellular immune responses in numerous animal models. Most DNA vaccines have been administered parenterally; however, more effective protection against mucosal pathogens could be achieved with mucosal immunization. This review concentrates on the use of DNA vaccines for the induction of mucosal immunity.

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The mucosal surfaces are the primary sites for transmission of most infectious diseases. However, most conventional vaccines are administered parenterally [e.g.

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Developmental effects of ectopic expression of the glucocorticoid receptor DNA binding domain are alleviated by an amino acid substitution that interferes with homeodomain binding.

Mol Cell Biol

October 1999

Department of Medicine, Microbiology, and Immunology, The Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada K1Y 4E9.

Steroid hormone receptors are distinguished from other members of the nuclear hormone receptor family through their association with heat shock proteins and immunophilins in the absence of ligands. Heat shock protein association represses steroid receptor DNA binding and protein-protein interactions with other transcription factors and facilitates hormone binding. In this study, we investigated the hormone-dependent interaction between the DNA binding domain (DBD) of the glucocorticoid receptor (GR) and the POU domains of octamer transcription factors 1 and 2 (Oct-1 and Oct-2, respectively).

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Background: In spite of the large number of studies that have evaluated DNA-based immunization, few have directly compared the immune responses generated by different routes of immunization, particularly in non-human primates. Here we examine the ability of a hepatitis B surface antigen (HBsAg)-encoding plasmid to induce immune responses in mice and non-human primates (rhesus monkeys: Macaca mulatta) after delivery by a number of routes.

Materials And Methods: Eight different injected [intraperitoneal (IP), intradermal (ID), intravenous (IV), intramuscular (IM), intraperineal (IPER), subcutaneous (SC), sublingual (SL), vaginal wall (VW)] and six noninjected [intranasal inhalation (INH), intranasal instillation (INS), intrarectal (IR), intravaginal (IVAG), ocular (Oc), oral feeding (oral)] routes and the gene gun (GG) were used to deliver HBsAg-expressing plasmid DNA to BALB/c mice.

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Ku antigen-DNA conformation determines the activation of DNA-dependent protein kinase and DNA sequence-directed repression of mouse mammary tumor virus transcription.

Mol Cell Biol

June 1999

Departments of Medicine, Microbiology and Immunology, The Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada.

Mouse mammary tumor virus (MMTV) transcription is repressed by DNA-dependent protein kinase (DNA-PK) through a DNA sequence element, NRE1, in the viral long terminal repeat that is a sequence-specific DNA binding site for the Ku antigen subunit of the kinase. While Ku is an essential component of the active kinase, how the catalytic subunit of DNA-PK (DNA-PKcs) is regulated through its association with Ku is only beginning to be understood. We report that activation of DNA-PKcs and the repression of MMTV transcription from NRE1 are dependent upon Ku conformation, the manipulation of DNA structure by Ku, and the contact of Ku80 with DNA.

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Discrimination between NL1- and NL2-mediated nuclear localization of the glucocorticoid receptor.

Mol Cell Biol

February 1999

Department of Graduate Program in Biochemistry, The Loeb Health Research Institute at the Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada.

Glucocorticoid receptor (GR) cycles between a free liganded form that is localized to the nucleus and a heat shock protein (hsp)-immunophilin-complexed, unliganded form that is usually localized to the cytoplasm but that can also be nuclear. In addition, rapid nucleocytoplasmic exchange or shuttling of the receptor underlies its localization. Nuclear import of liganded GR is mediated through a well-characterized sequence, NL1, adjacent to the receptor DNA binding domain and a second, uncharacterized motif, NL2, that overlaps with the ligand binding domain.

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