Myocardial infarct size quantification by MR imaging early after coronary artery occlusion in dogs

The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium.     

Working profiles of dental hygienists in public and private practice in Finland and Norway

Abstract: Aim: The aim was to compare the working profiles of Finnish and Norwegian dental hygienists in public and private practice. To this end, we compared the procedures performed, the type of patients and the time devoted to different tasks. Subjects and methods: A questionnaire survey was originally conducted among a representative sample of dental hygienists in Finland (n = 595) and all authorized dental hygienists in Norway (n = 1 138) in 2004. The questionnaires collected data on the dental hygienists’ age, gender, year of graduation, working experience, work sector (private or public), working time spent on different activities and patient groups. The questionnaire also assessed how frequently the dental hygienists performed 25 different treatment measures. Results: The Norwegian dental hygienists spent 45.4% of their clinical time on check‐ups, whereas the Finns spent 49.9% of their time scaling. Dental hygienists in Finland and Norway working in the public sector spent 42.9% and 74.6% of their working time dealing with children and youth respectively. Conclusions: The working profiles of dental hygienists in Finland and Norway were quite similar, although differences in distribution by activities, type of patients and treatment measures do exist. The main activity of the dental hygienists was clinical work. The most commonly practised clinical activity among Finnish dental hygienists was scaling, and among Norwegians, check‐ups. Public dental hygienists in both countries dealt mainly with children and youths. Oral hygiene instruction was the most commonly reported treatment measure among both Finns and Norwegians.     

CT colonography and transient bacteraemia: implications for antibiotic prophylaxis

Objectives  

To determine the prevalence of transient bacteraemia after CT colonography (CTC).     

Quantitative coronary arteriography: design and validation

The authors assessed the performance of an automatic and rapid coronary quantification method by evaluating its accuracy in a stenosis phantom. Measurements were obtained with a lucite phantom with 2-, 3-, and 4-mm vessel diameters and concentric stenoses of 33%, 50%, 67%, and 75%. Direct digital angiographic images as well as 10 X 10 spot films and 35-mm cine angiography films were acquired with and without structural noise and mask subtraction. The films were digitized with magnification factors of one and two. An interactive analysis program was used to automatically determine the vessel edges with a Gaussian fit to the cross-sectional density profiles perpendicular to the center line of the vessel. Relative changes of the densitometric cross-sectional area along the vessel were used to assess the percentage of stenosis. Densitometric measurements were comparable in both digital and cine angiograms (r = .99 and r = .98, respectively); however, diameter measurements showed a higher variability and were dependent on the amount of magnification applied to the images.     

Expansion of peripheral blood CD5+ B cells is associated with mild disease in chronic hepatitis C virus infection

BACKGROUND/AIMS: Hepatitis C virus (HCV) infection is associated with the development of chronic liver disease and extra-hepatic manifestations, which include autoantibody production, immune-mediated diseases such as cryoglobulinaemia and B-cell lymphoproliferation. Recent identification of intra-hepatic clonal B cells capable of rheumatoid factor production, selective infection of B cells over T cells and of an HCV receptor on B lymphocytes strongly supports a central role for these cells in the immune response to HCV infection. In particular, CD5+ B cells which are capable of producing natural antibodies with autoreactive specificities are likely to be important in the development of HCV-associated autoimmunity and lymphoproliferation. METHODS: We have investigated the presence of CD5+ B cells in a unique cohort of HCV-infected women who were infected with a single inoculum of HCV genotype 1b following immunisation with contaminated anti-D immunoglobulin in 1977. RESULTS: CD5+ B cells are significantly increased in chronic HCV infection (37.66+/-1.92%) as compared with those with resolved infection (25.33+/-1.90%). High levels of CD5+ B cells were associated with the production of rheumatoid factor. The number of peripheral blood CD5+ B cells correlated negatively with histological activity index. CONCLUSIONS: The expansion of this B cell population in patients with active HCV infection may give rise to immune-mediated sequelae associated with HCV infection. This expanded population of CD5+ B cells may protect against the development of progressive liver disease.