Analysis of protein complexes using mass spectrometry.

The versatile combination of affinity purification and mass spectrometry (AP-MS) has recently been applied to the detailed characterization of many protein complexes and large protein-interaction networks. The combination of AP-MS with other techniques, such as biochemical fractionation, intact mass measurement and chemical crosslinking, can help to decipher the supramolecular organization of protein complexes. AP-MS can also be combined with quantitative proteomics approaches to better understand the dynamics of protein-complex assembly.

Do culturally sensitive services for Chinese in-patients make a difference?

Hospitals in large cities provide services to an increasingly diverse linguistic and cultural clientele. Some strategies adopted to improve services to non-English speaking populations include the use of bilingual social workers, interpreters and printed translation tools. In order to identify gaps in culturally sensitive care in a Canadian teaching hospital, this study surveyed a consecutive sample of 279 Chinese in-patients to determine satisfaction with hospital experience, levels of information about hospital routines and awareness of on-site Chinese cultural services.

Identification and analysis of in vitro cultured CD45-positive cells capable of multi-lineage differentiation.

We report on a subset of cells that co-purify with CD45-positive/Lineage minus (CD45(pos)/Lin(minus)) hematopoietic cells that are capable of in vitro differentiation into multi-potential cells including cells with neuroectoderm properties. Although these cells are CD45 positive and have properties similar to CD45-negative mesenchymal progenitor cells (MPC) derived from bone marrow (BM), they are neither hematopoietic cells nor mesenchymal cells. These CD45(pos)/Lin(minus) cells can be expanded in vitro, express the stem cell genes Oct-4 and Nanog and can be induced to differentiate into endothelial cells, osteoblasts, muscle cells and neural cells at frequencies similar to those reported for bone marrow mesenchymal cells.

Construct validity of computer-assisted assessment: quantification of movement processes during a vascular anastomosis on a live porcine model.

Background: Movement processes for 2 different suturing techniques within a single surgical task were quantified.

Methods: Junior (postgraduate years 1-2) and senior residents (postgraduate year 3 and higher) were tested on their ability to perform a vascular anastomosis on a live porcine model 1 week after a guided practice session. Two phases of 2 suturing techniques (parachute and running) were identified, and performance was evaluated during each phase using computer hand motion analysis (CHMA) and expert-based measures.

A randomized, controlled trial of heparin versus placebo infusion to prolong the usability of peripherally placed percutaneous central venous catheters (PCVCs) in neonates: the HIP (Heparin Infusion for PCVC) study.

Background: Mechanical and infectious complications shorten the effective duration of peripherally inserted central venous catheters. Heparin use to prevent such complications and prolong the usability of peripherally inserted central venous catheters is inconclusive.

Objective: Our goal was to evaluate the effectiveness of heparin in prolonging the usability of peripherally inserted central venous catheters in neonates.

Morbidity and mortality of patients with invasive group A streptococcal infections admitted to the ICU.

Study Objectives: To describe the clinical features and outcome of patients with invasive group A streptococcal (GAS) infections admitted to the ICU.

Design: Prospective, population-based surveillance for invasive GAS infections was conducted in Ontario from January 1992 until June 2002. All 62 patients meeting clinical and/or histopathologic criteria for invasive GAS who were admitted to the ICUs of four university-affiliated hospitals in Toronto, Canada were included.

Cartilage T2 assessment: differentiation of normal hyaline cartilage and reparative tissue after arthroscopic cartilage repair in equine subjects.

Purpose: To prospectively assess T2 mapping characteristics of normal articular cartilage and of cartilage at sites of arthroscopic repair, including comparison with histologic results and collagen organization assessed at polarized light microscopy (PLM).

Materials And Methods: Study protocol was compliant with the Canadian Council on Animal Care Guidelines and approved by the institutional animal care committee. Arthroscopic osteochondral autograft transplantation (OAT) and microfracture arthroplasty (MFx) were performed in knees of 10 equine subjects (seven female, three male; age range, 3-5 years).

The eggshell is required for meiotic fidelity, polar-body extrusion and polarization of the C. elegans embryo.

Background: Fertilization restores the diploid state and begins the process by which the single-cell oocyte is converted into a polarized, multicellular organism. In the nematode, Caenorhabditis elegans, two of the earliest events following fertilization are secretion of the chitinous eggshell and completion of meiosis, and in this report we demonstrate that the eggshell is essential for multiple developmental events at the one-cell stage.

Results: We show that the GLD (Germline differentiation abnormal)-1-regulated hexosamine pathway enzyme, glucosamine-6-phosphate N-acetyltransferase (GNA)-2, is required for synthesis of uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc), the substrate for eggshell chitin synthesis by chitin synthase-1 (CHS-1).

Coordinated steroid hormone-dependent and independent expression of multiple kallikreins in breast cancer cell lines.

The regulation of gene expression by steroid hormones plays an important role in the normal development and function of many organs, as well in the pathogenesis of endocrine-related cancers. Previous experiments have shown that many kallikrein genes are under steroid hormone regulation in breast cancer cell lines. We here examine the coordinated expression of multiple kallikrein genes in several breast cancer cell lines after steroid hormone stimulation.

Economic analysis of psychosocial group therapy in women with metastatic breast cancer.

Purpose: Metastatic breast cancer is associated with psychological distress in one-third of patients. We examined the impact of group psychosocial support on health care costs in metastatic breast cancer. Psychosocial interventions have been shown to reduce psychological distress in these patients.

Nitroglycerin attenuates human endothelial progenitor cell differentiation, function, and survival.

Endothelial progenitor cells (EPCs) participate in angiogenesis and the response to chronic ischemia. Risk factors and cardiovascular disease attenuate EPC number, function, and survival. Continuous therapy with nitroglycerin (glyceryl trinitrate; GTN) is associated with increased vascular oxidative stress, leading to nitrate tolerance and endothelial dysfunction.

Prenatal US and MR imaging findings of lissencephaly: review of fetal cerebral sulcal development.

The cerebral cortex develops in three overlapping stages: cell proliferation, neuronal migration, and cortical organization. Abnormal neuronal migration may result in lissencephaly, which is characterized by either the absence (agyria) or the paucity (pachygyria) of cerebral convolutions. The two main clinicopathologic types of lissencephaly may be differentiated according to their prenatal imaging features.

Sequence-specific recognition of RNA hairpins by the SAM domain of Vts1p.

The SAM domain of the Saccharomyces cerevisiae post-transcriptional regulator Vts1p epitomizes a subfamily of SAM domains conserved from yeast to humans that function as sequence-specific RNA-binding domains. Here we report the 2.0-A X-ray structure of the Vts1p SAM domain bound to a high-affinity RNA ligand.

The effects of vanadium treatment on bone in diabetic and non-diabetic rats.

Vanadium-based drugs lower glucose by enhancing the effects of insulin. Oral vanadium drugs are being tested for the treatment of diabetes. Vanadium accumulates in bone, though it is not known if incorporated vanadium affects bone quality.

Formation of a nucleus pulposus-cartilage endplate construct in vitro.

Intervertebral disc (IVD) degeneration is a common problem and treatment options for persistent symptomatic disease are limited. Tissue engineering is being explored for its ability to reconstitute the functional components of the IVD. The purpose of this study was to determine whether it was possible to form in vitro a triphasic construct consisting of nucleus pulposus (NP), cartilage endplate (CEP), and a porous calcium polyphosphate (CPP) bone substitute.

CO: A chemical ontology for identification of functional groups and semantic comparison of small molecules.

A novel chemical ontology based on chemical functional groups automatically, objectively assigned by a computer program, was developed to categorize small molecules. It has been applied to PubChem and the small molecule interaction database to demonstrate its utility as a basic pharmacophore search system. Molecules can be compared using a semantic similarity score based on functional group assignments rather than 3D shape, which succeeds in identifying small molecules known to bind a common binding site.

Increased subcortical patellar signal intensity at T2-weighted MR imaging: a subacute finding after knee injury.

Purpose: To investigate the temporal prevalence of a rim of increased signal intensity in the subcortical part of the patella at T2-weighted magnetic resonance (MR) imaging after arthroscopic knee surgery or knee injury.

Materials And Methods: The prospective and retrospective components of the study were performed after receiving approval from the institutional research ethics board. Written informed consent was obtained for the prospective component of the study.

Effect of vitamin C and L-NMMA on the inotropic response to dobutamine in patients with heart failure.

The positive effect of vitamin C on left ventricular (LV) inotropic responses to dobutamine, observed in patients with preserved LV function, is lost in heart failure (HF). We tested the hypothesis that in HF, endogenous nitric oxide (NO) opposes the positive effect of vitamin C on adrenergically stimulated contractility by examining the effects of vitamin C on dobutamine responses during NO synthase inhibition. In 11 HF patients, a micromanometer-tipped catheter was inserted into the LV and an infusion catheter was positioned in the left main coronary artery.

Plk4 haploinsufficiency causes mitotic infidelity and carcinogenesis.

The polo-like kinase Plk4 (also called Sak) is required for late mitotic progression, cell survival and postgastrulation embryonic development. Here we identified a phenotype resulting from Plk4 haploinsufficiency in Plk4 heterozygous cells and mice. Plk4+/- embryonic fibroblasts had increased centrosomal amplification, multipolar spindle formation and aneuploidy compared with wild-type cells.

Prevalence and characterization of invasive isolates of Streptococcus pyogenes with reduced susceptibility to fluoroquinolones.

Fluoroquinolone susceptibility testing was performed on invasive group A streptococcus isolates from 1992-1993 and 2003 from Ontario, Canada. None were nonsusceptible to levofloxacin. Two of 153 (1.

Sak/Plk4 and mitotic fidelity.

Sak/Plk4 differs from other polo-like kinases in having only a single polo box, which assumes a novel dimer fold that localizes to the nucleolus, centrosomes and the cleavage furrow. Sak expression increases gradually in S through M phase, and Sak is destroyed by APC/C dependent proteolysis. Sak-deficient mouse embryos arrest at E7.

Cre recombinase specificity defined by the tau locus.

We generated a transgenic mouse line (tau::Cre) by targeting the Cre to the tau locus (Mapt). Based on previous reports on the expression of Tau during development, we expected the Cre recombinase to be expressed in a neuron-specific and pan-neuronal manner. However, intercrosses between the tau::Cre and the Cre-activatable reporter animals resulted in offspring with recombination either restricted to the nervous system or throughout the entire conceptus, indicating expression of Tau early in development.