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Background: Elevated levels of circulating matrix metalloproteinase-9 (MMP-9) have been demonstrated in patients with established coronary artery disease (CAD). The aim of this study was to analyse levels of MMP-9 in a population free from symptomatic CAD and investigate their associations with cardiovascular (CV) risk factors, including C-reactive protein (CRP)., Methods: A cross-sectional study was performed in a population based random sample aged 45-69 (n = 345, 50% women). MMP-9 levels were measured in EDTA-plasma using an ELISA-method. CV risk factors were measured using questionnaires and standard laboratory methods., Results: Plasma MMP-9 was detectable in all participants, mean 38.9 ng/mL (SD 22.1 ng/mL). Among individuals without reported symptomatic CAD a positive association (p<0.001) was seen, for both men and women, of MMP-9 levels regarding total risk load of eight CV risk factors i.e. blood pressure, dyslipidemia, diabetes, obesity, smoking, alcohol intake, physical activity and fruit and vegetable intake. The association was significant also after adjustment for CRP, and was not driven by a single risk factor alone. In regression models adjusted for age, sex, smoking, alcohol intake and CRP, elevated MMP-9 levels were independently positively associated with systolic blood pressure (p = 0.037), smoking (p<0.001), alcohol intake (p = 0.003) and CRP (p<0.001). The correlation coefficient between MMP-9 and CRP was r = 0.24 (p<0.001)., Conclusions: In a population without reported symptomatic CAD, MMP-9 levels were associated with total CV risk load as well as with single risk factors. This was found also after adjustment for CRP.

We present a new five-dimensional (5-D) space representation of diffusion magnetic resonance imaging (dMRI) of high angular resolution. This 5-D space is basically a non-Euclidean space of position and orientation in which crossing fiber tracts can be clearly disentangled, that cannot be separated in three-dimensional position space. This new representation provides many possibilities for processing and analysis since classical methods for scalar images can be extended to higher dimensions even if the spaces are not Euclidean. In this paper, we show examples of how regularization and segmentation of dMRI is simplified with this new representation. The regularization is used with the purpose of denoising and but also to facilitate the segmentation task by using several scales, each scale representing a different level of resolution. We implement in five dimensions the Chan-Vese method combined with active contours without edges for the segmentation and the total variation functional for the regularization. The purpose of this paper is to explore the possibility of segmenting white matter structures directly as entirely separated bundles in this 5-D space. We will present results from a synthetic model and results on real data of a human brain acquired with diffusion spectrum magnetic resonance imaging (MRI), one of the dMRI of high angular resolution available. These results will lead us to the conclusion that this new high-dimensional representation indeed simplifies the problem of segmentation and regularization.

Background: During the last years, neutrophils have emerged as important players in atherogenesis. They are highly activated in peripheral blood of patients with unstable angina. Moreover, a primed state of circulating neutrophils has been proposed in patients with stable angina. Our aim was to investigate the neutrophil activation status in patients with stable coronary artery disease (CAD) at conventional drug treatment., Methodology and Principal Findings: Thirty patients with stable CAD and 30 healthy controls were included using a paired design. The neutrophil expression of CD18 and high-affinity state of CD11b was analysed by flow cytometry before and after stimulation with chemoattractants. Also, the production of reactive oxygen species (ROS) was determined by chemiluminescence. During basal conditions, the neutrophil expression of CD18 or high-affinity state of CD11b did not differ between patients and controls. Chemoattractants (Interleukin-8 and Leukotriene B(4)) did not increase either the expression or the amount of high-affinity CD11b/CD18-integrins in CAD patients compared to controls, and had no effect on the production of ROS. On the other hand, the ROS production in response to C3bi-opsonised yeast particles and the neutrophils' inherent capacity to produce ROS were both significantly decreased in patients., Conclusion/significance: We could not find any evidence that neutrophils in patients with stable CAD were primed, i.e. more prone to activation, compared to cells from healthy controls. According to our data, the circulating neutrophils in CAD patients rather showed an impaired activation status. It remains to be elucidated whether the neutrophil dysfunction in CAD is mainly a marker of chronic disease, an atherogenic factor or a consequence of the drug treatment.

Objectives: To study the prevalence of active cytomegalovirus (CMV) infection in patients with stable and unstable conditions of coronary artery disease (CAD)., Design: Forty patients with acute coronary syndrome (ACS), 50 patients with stable angina and angiographically verified CAD (SA) and 50 clinically healthy controls were included. Monocytes were isolated from peripheral blood and CMV-RNA expression was determined by a nested RT-PCR assay. CMV IgM and IgG antibodies, interleukin-(IL)-6, IL-10 and CRP were measured in serum., Results: The prevalence of active CMV infection was significantly higher in patients with ACS (15%) and in patients with SA (10%) compared with controls (2%) (p<0.001). The presence of an active CMV infection was associated with increased serum concentrations of IL-6., Conclusions: Active CMV infection was found to a larger extent in CAD patients than in healthy controls. The data indicate that CAD patients are more susceptible to reactivation of CMV and put new focus on the role of CMV in atherosclerosis.

Background and Aims: Low circulating levels of carotenoids have been associated with cardiovascular disease. The distribution of different carotenoids in blood may have an impact on the cardioprotective capacity. The aim of the present study was to determine the plasma levels of 6 major carotenoids in patients with coronary artery disease (CAD) and relate the findings to clinical, metabolic and immune parameters., Methods and Results: Plasma levels of oxygenated carotenoids (lutein, zeaxanthin, beta-cryptoxanthin) and hydrocarbon carotenoids (alpha-carotene, beta-carotene, lycopene) were determined in 39 patients with acute coronary syndrome, 50 patients with stable CAD and 50 controls. Serological assays for inflammatory activity and flow cytometrical analysis of lymphocyte subsets were performed. Both patient groups had significantly lower plasma levels of oxygenated carotenoids, in particular lutein+zeaxanthin, compared to controls. Low levels of oxygenated carotenoids were associated with smoking, high body mass index (BMI), low high density lipoprotein (HDL) cholesterol and, to a minor degree, inflammatory activity. Plasma levels of lutein+zeaxanthin were independently associated with the proportions of natural killer (NK) cells, but not with other lymphocytes, in blood., Conclusion: Among carotenoids, lutein+zeaxanthin and beta-cryptoxanthin were significantly reduced in CAD patients independent of clinical setting. The levels were correlated to a number of established cardiovascular risk factors. In addition, the relationship between NK cells and lutein+zeaxanthin may indicate a particular role for certain carotenoids in the immunological scenario of CAD.

Objective: The use of statins has shown several anti-inflammatory actions, including modulatory effects on T cells in vitro. Since the effects on human T cells in vivo are less clarified, our aim was to investigate the effects of simvastatin on human T cells in vivo and ex vivo., Methods and Results: A randomized, double-blind, placebo-controlled study design was applied. Eighty volunteers with mild to moderate hypercholesterolemia received either simvastatin 40 mg or placebo for 6 weeks. The serum levels of C-reactive protein (CRP) were significantly reduced by simvastatin. The proportions of CD4+ and CD8+ T cell subsets expressing early (CD25) or late (HLA-DR) activation markers, as assessed by flow cytometry, were not changed by simvastatin. However, simvastatin tended to increase the density of HLA-DR and L-selectin per CD8+ T cell. The T helper(h)1/Th2 response was evaluated by stimulatory assays followed by intra-cellular staining of interferon-gamma and interleukin-4. Simvastatin treatment did not affect the Th1 response but the results indicated a potential to suppress Th2., Conclusion: Simvastatin treatment resulted in a few discrete changes as regards peripheral T cells. However, the findings do not provide evidence that simvastatin-induced anti-inflammatory actions are related to any significant modulatory effects on human T cells in clinically healthy men with hypercholesterolemia.

Peri-apical radiographs have been used to identify women with low bone mineral density (BMD) in various parts of the skeleton, but their usefulness for men has not been elucidated. The aim of this study was to test if the mandibular bone structure and bone mass in men and women were related to the BMD of the forearms, determined by dual X-ray absorptiometry, in 42 men and 42 women (aged 18-84 yr). Mandibular alveolar thickness was measured in casts, and alveolar 'bone mass' was estimated on digital radiographs using gray-shade distribution. Alveolar bone structure was evaluated visually (trabecular pattern) on analog radiographs and with its bone texture on digitized radiographs. Bone texture was correlated to BMD in both men and women. BMD was correlated to alveolar bone mass and trabecular pattern in women, but not in men. Bone texture and body mass index (BMI) explained 57% of the variance in BMD for men, whereas trabecular pattern and age explained 50% of the variance in BMD for women. Sparse trabeculation was associated with osteopenia. We conclude that alveolar bone texture and BMI are predictors of BMD for men, and age and trabecular pattern are predictors of BMD for women.

Objectives: To investigate for the first time whether the plasma CXCL16 concentration is altered in coronary artery disease (CAD) patients., Background: Accumulating evidence suggests that the novel chemokine/scavenger receptor CXCL16/SR-PSOX is involved in the development of atherosclerosis and CAD., Methods: Using ELISA we assessed the plasma CXCL16 concentration in 40 stable angina pectoris (SAP) patients, 17 unstable angina pectoris/non-ST-elevation myocardial infarction (UAP/non-STEMI) patients, 387 survivors of a first myocardial infarction (MI) and healthy control subjects (44 controls for SAP and UAP/non-STEMI patient groups and 387 controls for post-MI patients)., Results: SAP patients exhibited significantly lower median CXCL16 levels (2111 pg/ml) than the corresponding control subjects (2678 pg/ml) (P=0.0012). UAP/non-STEMI patients also appeared to have lower CXCL16 levels (2192 pg/ml) compared with controls (NS). Patients investigated 3 months after MI tended (P=0.07) to have lower CXCL16 levels (2529 pg/ml) than the corresponding controls (2638 pg/ml). There were no significant correlations between CXCL16 levels and different measures of CAD severity determined by quantitative coronary angiography in post-MI patients. Neither patients nor controls exhibited significant correlations between CXCL16 levels and plasma lipoprotein fractions, inflammatory cytokines, C-reactive protein or numbers of inflammatory cells in peripheral blood., Conclusions: The finding that lower plasma CXCL16 concentration is associated with CAD might indicate a potential atheroprotective function of CXCL16.

The complex structural organization of the white matter of the brain can be depicted in vivo in great detail with advanced diffusion magnetic resonance (MR) imaging schemes. Diffusion MR imaging techniques are increasingly varied, from the simplest and most commonly used technique-the mapping of apparent diffusion coefficient values-to the more complex, such as diffusion tensor imaging, q-ball imaging, diffusion spectrum imaging, and tractography. The type of structural information obtained differs according to the technique used. To fully understand how diffusion MR imaging works, it is helpful to be familiar with the physical principles of water diffusion in the brain and the conceptual basis of each imaging technique. Knowledge of the technique-specific requirements with regard to hardware and acquisition time, as well as the advantages, limitations, and potential interpretation pitfalls of each technique, is especially useful., ((c) RSNA, 2006.)

In diffusion MRI, standard approaches for fibertract identification are based on algorithms that generate lines of coherent diffusion, currently known as tractography. A tract is then identified as a set of such lines selected on some criteria. In the present study, we investigate whether fibertract identification can be formulated as a segmentation task that recognizes a fibertract as a region where diffusion is intense and coherent. Indeed, we show that it is possible to segment efficiently well-known fibertracts with classical image processing methods provided that the problem is formulated in a five-dimensional space of position and orientation. As an example, we choose to adapt to this newly defined high-dimensional non-Euclidean space, called position orientation space, an algorithm based on the hidden Markov random field framework. Structures such as the cerebellar peduncles, corticospinal tract, association bundles can be identified and represented in three dimensions by a back projection technique similar to maximum intensity projection. Potential advantages and drawbacks as compared to classical tractography are discussed; for example, it appears that our formulation handles naturally crossing tracts and is not biased by human intervention.

Background: Plaque rupture is often associated with breakdown of the extracellular matrix in the shoulder region of a plaque. We tested whether plasma concentrations of various matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase-1 (TIMP-1) could serve as markers for plaque instability as well as relationships between plasma MMPs and inflammatory markers., Methods: The study group included 65 men with angiographically verified CAD (45 with stable and 20 with unstable CAD) and 28 healthy controls. Circulating MMP, TIMP-1, C-reactive protein, and cytokine concentrations were measured by ELISA. Leukocyte subtype counts in whole blood were determined, and T-cell subsets and natural killer cells were measured by flow cytometry. Differences in continuous variables between groups were tested by ANOVA with the Scheffé F-test used as a post hoc test, and correlations were analyzed by a linear regression method., Results: The plasma concentration of MMP-7 was increased in patients with stable and unstable CAD, whereas MMP-2 and -3 concentrations were decreased. The plasma concentration of TIMP-1 was significantly increased in patients with unstable CAD. MMP-2, -3, and -7 showed no correlations with established markers of inflammation. However, MMP-2 correlated positively with the number of natural killer cells in patients with stable and unstable CAD., Conclusion: Plasma concentrations of MMPs and TIMPs may be markers of CAD but appear to be differentially regulated.

The association between skeletal bone mineral density (BMD) and mandibular alveolar bone mass has been reported to be rather weak, probably due to local functional factors. Many new investigations are therefore focused on assessing the mandibular bone structure. No long-term structural alterations have been reported in human mandibular bone with the exception of alveolar crest changes related to periodontal disease. The aim of this prospective study was to investigate dentate women to see if possible alterations in the radiographic characteristics of the mandibular alveolar bone are related to changes in BMD. The BMD of 131 women (initial age 22-75 years) was determined in the distal forearm with dual energy X-ray absorptiometry on two occasions separated by an interval of 5 years. Mandibular alveolar bone mass (MABM) was assessed both by the optical density and by the grey-level value on digitized, calibrated, periapical radiographs. The radiographic alveolar bone structure was evaluated with a visual index [Lindh C, Petersson A, Rohlin M. Assessment of the trabecular pattern before endosseous implant treatment: diagnostic outcome of periapical radiography in the mandible. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1996;82:335-43. ] and digitally by the alveolar bone texture. MABM decreased significantly during the 5-year period. Changes in MABM, evaluated by the mean grey-level value of a bone segment between the premolars, were correlated to changes in skeletal BMD (r = 0.33, P < 0.001). Changes in MABM, evaluated by the optical density, did not correlate to changes in skeletal BMD. The overall trabecular pattern did not change during the study period, but small changes in the bone texture were measured. The changes in the bone texture were correlated with BMD change (r = 0.39, P < 0.001). We conclude that changes in the mandibular alveolar bone do reflect changes in the skeletal BMD, and these may be estimated on periapical radiographs by changes in their grey-level value and their texture.

Mitochondrial changes are frequently encountered in sporadic inclusion-body myositis (s-IBM). Cytochrome c oxidase (COX)-deficient muscle fibers and large-scale mitochondrial DNA (mtDNA) deletions are more frequent in s-IBM than in age-matched controls. COX deficient muscle fibers are due to clonal expansion of mtDNA deletions and point mutations in segments of muscle fibers. Such segments range from 75 microm to more than 1,000 microm in length. Clonal expansion of the 4977 bp "common deletion" is a frequent cause of COX deficient muscle fiber segments, but many other deletions also occur. The deletion breakpoints cluster in a few regions that are similar to what is found in human mtDNA deletions in general. Analysis in s-IBM patients of three nuclear genes associated with multiple mtDNA deletions, POLG1, ANT1 and C10orf2, failed to demonstrate any mutations. In s-IBM patients with high number of COX-deficient fibers, the impaired mitochondrial function probably contribute to muscle weakness and wasting. Treatment that has positive effects in mitochondrial myopathies may be tried also in s-IBM.

Background: Natural killer (NK) cells are important components of the innate immune system and have a potential role in the regulation of autoimmunity. In the present study, we evaluated the NK cells in patients with coronary artery disease (CAD) and related the findings to clinical and laboratory parameters of the disease., Methods and Results: We studied 45 patients with acute coronary syndrome (ACS), 50 patients with stable angina and angiographically verified CAD (SA) and 50 healthy controls. The distribution of NK cell subsets was determined by flow cytometry and NK cell-mediated cytotoxicity was quantified ex vivo. Both ACS and SA patients had significantly reduced numbers of CD56(dim) NK cells compared with controls. The patients also exhibited a significant decrease in NK cell activity. The loss in NK cell function was not related to inflammatory activity or metabolic status., Conclusion: Both stable and unstable conditions of CAD were associated with a redistribution of circulating lymphocytes, comprising a significant reduction of CD56(dim) NK cells and a concomitant loss of NK cell function. The findings suggest the presence of a persistent immune aberration in CAD patients independent of their clinical setting or systemic inflammatory state.

Background: Survival of a myocardial infarction and subsequent prognosis are highly dependent on the time between onset of symptoms and medical intervention., Design: This cross-sectional study examines whether patients who used the psychological defence mechanism of denial when faced with symptoms of a first-time myocardial infarction tended to also show a prolonged delay in going to the hospital and to be less willing to participate in a cardiac rehabilitation programme., Methods: One hundred and seven patients, 78 men and 29 women, were enrolled in this study. The sample was divided into two groups depending on whether the patients sought medical help within 4 h after they began experiencing myocardial infarction symptoms (non-delayers) or whether they waited longer (delayers). Denial was measured with the Hackett and Cassem semi-structured interview 3-5 days after the patients entered the hospital. Data on participation (attenders) or not (non-attenders) in the rehabilitation programme was also obtained., Results: Forty-nine patients exhibited a prolonged delay and 76 patients did not attend the rehabilitation programme. Both prolonged delay and a lesser readiness to attend the rehabilitation programme that was offered were related to a greater use of denial. In addition, the great majority of the patients categorized as being high deniers were found to also be both delayers and non-attenders., Conclusions: The results suggest denial to increase the health risks of persons potentially prone to myocardial infarction. If our knowledge about this psychological defence mechanism is increased, we might be able to reach more patients in alternative and individually based cardiac rehabilitation programmes.

The EU Water Framework Directive will require river-basin management plans in order to achieve good ecological status and find the most cost-efficient nitrogen (N) leaching abatement measures. Detailed scenario calculations based on modeling methods will be valuable in this regard. This paper describes the approach and an application with a coefficient method based on the simulation model SOILNDB for quantification of N leaching from arable land and for prediction of the effect of abatement scenarios for the Rönneå catchment (1900 km2) in southern Sweden. Cost calculations for the different measures were also performed. The results indicate that the individual measures-cover crop and spring plowing, late termination of ley and fallow, and spring application of manure-would only reduce N leaching by between 5% and 8%. If all measures were combined and winter crops replaced by their corresponding spring variants, a 21% reduction in N leaching would be possible. However, this would require total fulfillment of the suggested measures.

In this paper, we present a 3D geometric flow designed to segment the main core of fiber tracts in diffusion tensor magnetic resonance images. The fundamental assumption of our fiber segmentation technique is that adjacent voxels in a tract have similar properties of diffusion. The fiber segmentation is carried out with a front propagation algorithm constructed to fill the whole fiber tract. The front is a 3D surface that evolves with a propagation speed proportional to a measure indicating the similarity of diffusion between the tensors lying on the surface and their neighbors in the direction of propagation. We use a level set implementation to assure a stable and accurate evolution of the surface and to handle changes of topology of the surface during the evolution process. The fiber tract segmentation method does not need a regularized tensor field since the surface is automatically smoothed as it propagates. The smoothing is done by an intrinsic surface force, based on the minimal principal curvature. This segmentation can be used for obtaining quantitative measures of the diffusion in the fiber tracts and it can also be used for white matter registration and for surgical planning.

Background: Fibrous cap thickness (FCT) is an important determinant of atheroma stability. We evaluated the feasibility and potential clinical implications of measuring the FCT of internal carotid artery plaques with a new ultrasound system based on boundary detection by dynamic programming., Methods and Results: We assessed agreement between ultrasound-obtained FCT values and those measured histologically in 20 patients (symptomatic [S]=9, asymptomatic [AS]=11) who underwent carotid endarterectomy for stenosing (>70%) carotid atheromas. We subsequently measured in vivo the FCT of 58 stenosing internal carotid artery plaques (S=22, AS=36) in 54 patients. The accuracy in discriminating symptomatic from asymptomatic plaques was assessed by receiver operating characteristic curves for the minimal, mean, and maximal FCT. Decision FCT thresholds that provided the best correct classification rates were identified. Agreement between ultrasound and histology was excellent, and interobserver variability was small. Ultrasound showed that symptomatic atheromas had thinner fibrous caps (S versus AS, median [95% CI]: minimal FCT=0.42 [0.34 to 0.48] versus 0.50 [0.44 to 0.53] mm, P=0.024; mean FCT=0.58 [0.52 to 0.63] versus 0.79 [0.69 to 0.85] mm, P<0.0001; maximal FCT=0.73 [0.66 to 0.92] versus 1.04 [0.94 to 1.20] mm, P<0.0001). Mean FCT measurement demonstrated the best discriminatory accuracy (area under the curve [95% CI]: minimal 0.74 [0.61 to 0.87]; mean 0.88 [0.79 to 0.97]; maximal 0.82 [0.71 to 0.93]). The decision threshold of 0.65 mm (mean FTC) demonstrated the best correct classification rate (82.8%; positive predictive value 75%, negative predictive value 88.2%)., Conclusions: FCT measurement of carotid atheroma with ultrasound is feasible. Discrimination of symptomatic from asymptomatic plaques with mean FCT values is good. Prospective studies should determine whether this ultrasound marker is reliable.

Despite political efforts, diffuse pollution from agriculture continues to be the single largest source of nitrogen (N) emissions into the aquatic environment in many countries and regions. This fact, and the recent enactment of a new Swedish environmental code, led to the design of a study targeted at the evaluation of new N pollution abatement strategies. An actor game was chosen as the key component of the study, with a focus on four major goals: to test the implementability of legally binding environmental quality standards for nitrate concentration in groundwater and N transport to the sea, to find sets of agriculturally feasible and cost-effective measures to decrease N loads, to investigate the possibilities for collective action through negotiated and institutionalized actor cooperation, and to investigate the role of mathematical modeling in environmental N management. Characteristics from the agriculturally dominated catchment of Genevadsån (224 km2) on the southwest coast of Sweden served as the playing field for the actor game. The most noteworthy result from the study was that it appeared to be possible to meet ambitious environmental N standards with less economically drastic measures than anticipated by most of the participants. The actor game was shown to be a good method for learning about the new Swedish environmental code and its application and for gaining deeper insight into the issues of N management. In addition, the actor game functioned as an arena for gaining a more thorough understanding of the views of different stakeholders.

Several lines of evidence indicate that increased inflammatory activity in peripheral blood is associated with the acute coronary syndrome. Systemic inflammation in clinically stable conditions of coronary artery disease has been less studied. We examined cytokine profiles in 20 patients who had acute coronary syndrome, 45 who had angiographically verified coronary artery disease and stable angina pectoris, and 45 healthy controls. Circulating levels of C-reactive protein, interleukin-1 receptor antagonist, interleukin-2 receptor, interleukin-6, interleukin-10, and interleukin-18 were determined. Subpopulations of peripheral immune cells, including neutrophil-platelet aggregates, were analyzed by 3-color flow cytometry using a panel of monoclonal antibodies. Patients who had acute coronary syndrome and stable angina pectoris had significantly higher levels of C-reactive protein, interleukin-6, and interleukin-1 receptor antagonist than did controls, whereas levels of interleukin-2 receptor, interleukin-10, and interleukin-18 were similar across groups. Patients had significantly more neutrophils, and the numbers of neutrophil-platelet aggregates were particularly large in patients who had stable angina pectoris. High levels of C-reactive protein, interleukin-6, and interleukin-1 receptor antagonist in patients were significantly related to numbers of neutrophils and neutrophil-platelet aggregates but not to other immune cell subpopulations. The data suggest that the interaction between neutrophils and platelets is an important component of proinflammatory activity seen in peripheral blood of stable and unstable forms of coronary artery disease.

We present a method for segmenting white matter tracts from high angular resolution diffusion MR. images by representing the data in a 5 dimensional space of position and orientation. Whereas crossing fiber tracts cannot be separated in 3D position space, they clearly disentangle in 5D position-orientation space. The segmentation is done using a 5D level set method applied to hyper-surfaces evolving in 5D position-orientation space. In this paper we present a methodology for constructing the position-orientation space. We then show how to implement the standard level set method in such a non-Euclidean high dimensional space. The level set theory is basically defined for N-dimensions but there are several practical implementation details to consider, such as mean curvature. Finally, we will show results from a synthetic model and a few preliminary results on real data of a human brain acquired by high angular resolution diffusion MRI.

Background: Angiotensin II (Ang II) increases levels of aldosterone and plasminogen activator inhibitor-1 (PAI-1). Both aldosterone and PAI-1 seem to promote cardiovascular (CV) injury. Our objective was to determine the roles of PAI-1 and aldosterone in the development of myocardial and renal damage in a model with high Ang II and low nitric oxide (NO) availability, a pattern seen in patients with heart failure, diabetes mellitus, and arteriosclerosis., Methods and Results: Mice on a moderately high sodium diet were treated with the NO synthase inhibitor NG-nitro-l-arginine methyl ester (L-NAME) for 14 days plus Ang II during days 8 through 14. The roles of aldosterone and PAI-1 in the development of CV injury were assessed using the mineralocorticoid receptor antagonist spironolactone (0, 1.5, 15, and 50 mg x 100 g(-1) x day(-1)) and PAI-1-deficient mice (PAI-1-/-). Ang II/L-NAME-treated mice showed glomerular ischemia, proteinuria, and necrosis of myocytes and vascular smooth muscle cells with an associated mixed inflammatory response, deposition of loose collagen, and neovascularization. Compared with saline-drinking mice, Ang II/L-NAME-treated mice had significantly increased heart to body weight (HW/BW) ratios, cardiac and renal damage assessed by histological examination, PAI-1 immunoreactivity, and proteinuria. Spironolactone treatment decreased PAI-1 immunoreactivity and reduced in a dose-dependent fashion cardiac and renal damage. PAI-1-/- animals had a similar degree of CV injury as PAI-1+/+ animals., Conclusions: Mineralocorticoid receptor antagonism, but not PAI-1 deficiency, protected mice from developing Ang II/L-NAME-mediated myocardial and vascular injury and proteinuria, suggesting that aldosterone, but not PAI-1, plays a key role in the development of early Ang II/L-NAME-induced cardiovascular injury.

Objectives: The nature of the immune response in coronary artery disease (CAD) is not fully defined. One pathogen that has been linked to atherogenesis, cytomegalovirus (CMV), is known to exert strong and long-lasting effects on peripheral T cells. In the present study, we investigated the effect of prior CMV infection on the immune system in CAD patients., Subjects: Patients with stable angina and angiographically verified CAD (n=43) and clinically healthy controls (n=69) were included., Methods: The expression of CD57 and CD28 on peripheral CD4+ and CD8+ T cells was evaluated with three-colour flow cytometry. The findings were related to serological markers of inflammation, T-cell activation and CMV seropositivity., Results: An expansion of CD8+ T cells expressing CD57 but lacking CD28 was seen in the patient group. The numbers of CD8+ CD57+ and CD8+ CD28-T-cell subsets were independently related to CMV seropositivity (P<0.001) but also to CAD per se (P<0.05). Serum concentrations of C-reactive protein (CRP) and soluble interleukin-2 receptor (sIL-2R) were elevated in the patients but not related to CMV or CD8+ T-cell subsets., Conclusion: A pronounced shift in peripheral T-cell homeostasis was observed in CAD patients. Primarily CMV infection but also CAD per se contributed to the expansion of CD8+ T-cell subsets. The T-cell changes were not related to a systemic inflammatory response but should rather be considered as markers of a chronic antigen exposure and/or immunosenescence in CAD.

Several approaches have been used to trace axonal trajectories from diffusion MRI data. If such techniques were first developed in a deterministic framework reducing the diffusion information to one single main direction, more recent approaches emerged that were statistical in nature and that took into account the whole diffusion information. Based on diffusion tensor MRI data coming from normal brains, this paper presents how brain connectivity could be modelled globally by means of a random walk algorithm. The mass of connections thus generated was then virtually dissected to uncover different tracts. Corticospinal, corticobulbar, and corticothalamic tracts, the corpus callosum, the limbic system, several cortical association bundles, the cerebellar peduncles, and the medial lemniscus were all investigated. The results were then displayed in the form of an in vivo brain connectivity atlas. The connectivity pattern and the individual fibre tracts were then compared to known anatomical data; a good matching was found.

Background and Aim: Low serum levels of antioxidant vitamins are associated with coronary artery disease (CAD). An immunomodulatory effect of antioxidants has been proposed. The aim of the study was to investigate whether an increased immune response in CAD patients was associated with suppressed circulating levels of antioxidant vitamins., Methods and Results: Forty-four men with stable angina and angiographically verified CAD were included as well as 69 healthy controls. T cell subsets in peripheral blood were quantified by 3-colour flow cytometry. C-reactive protein (CRP), soluble interleukin-2 receptor (sIL-2R) and the lipophilic antioxidants alpha-tocopherol, beta-carotene and lycopene were determined in serum. Compared with controls, patients had signs of an enhanced inflammatory activity assessed by significantly increased levels of CRP, sIL-2R and CD4+CD25+T cell subsets. Patients also had significantly lower beta-carotene and lycopene levels whereas a-tocopherol levels did not differ. The increased inflammatory/immune parameters in patients showed a significant inverse relationship to serum beta-carotene but not to lycopene or alpha-tocopherol., Conclusions: Low serum beta-carotene in CAD patients reflects activation of the immune system. Inflammation should be considered as an important confounding factor when analysing data on beta-carotene and CAD.

Objectives: To evaluate the effects of long-term home self-treatment with thoracic epidural analgesia (TEA) on angina, quality of life, and safety., Design: Prospective consecutive pilot study., Setting: Department of Cardiology, Heart Center, Linköping University Hospital., Participants: Between January 1998 and January 2000, 37 consecutive patients with refractory angina began treatment with TEA, using a subcutaneously tunnelled epidural catheter., Interventions: The patients were trained to provide self-treatment at home with intermittent injections of bupivacaine. Data were collected until January 2001, and the follow-up for each patient was 1 to 3 years., Measurements and Main Results: All but 1 of the patients improved symptomatically. The improvement was maintained throughout the treatment period (4 days to 3 years). The Canadian Cardiovascular Society angina class decreased from 3.6 to 1.7, frequency of anginal attacks decreased from 46 to 7 a week, nitroglycerin intake decreased from 32 to 5 a week, and the overall self-rated quality of life assessed by visual analog scale increased from 24 to 76 (all p < 0.001). No serious catheter-related complications occurred; however, 51% of the catheters became displaced and a new one had to be inserted during the study., Conclusion: Long-term self-administered home treatment with TEA seems to be an effective and safe adjuvant treatment for patients with refractory angina. It produces symptomatic relief of angina and improves the quality of life., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

In a randomized, double-blind trial in 3086 patients with unstable angina pectoris or non-Q wave myocardial infarction we investigated if 80 mg of atorvastatin daily could improve outcome of cardiovascular events during a short period of time (16 weeks) compared with placebo. Baseline LDL cholesterol was 3.2 mmol L-1 (124 mg dL-1) and decreased by 40% to 1.9 mmol L-1 (72 mg dL-1) during atorvastatin treatment. The primary endpoint, which was a composite of death, non-fatal acute myocardial infarction, cardiac arrest with resuscitation or recurrent symptomatic myocardial ischaemia with objective evidence and requiring emergency rehospitalization occurred in 228 patients (14.8%) in the atorvastatin group and 269 patients (17.4%) in the placebo group. The relative risk was 0.84 and 95% confidence interval was 0.70-1.00 (P = 0.048). Thus for patients with acute coronary syndromes, lipid-lowering therapy with high dose atorvastatin reduces recurrent ischaemic events in the short-term. A possible mechanism behind this rapid clinical effect induced by statin treatment is on inflammatory processes. Recent studies strongly suggest that acute T-cell activation is involved in the pathogenesis of unstable angina. In another study we investigated whether circulating T cells showed signs of activation in patients with stable angina pectoris (SA). Systemic venous blood samples were taken from 38 men with SA and 42 healthy controls. The T-cell receptor expression was assessed by three-colour flow cytometry using monoclonal antibodies against CD3,CD4, CD8, CD25 and human leucocyte antigen (HLA)-DR. Soluble interleukin-2 receptor (sIL-2R) was measured as the circulating form in serum. Levels of circulating CD3+ and CD4+ T cells tended to be higher in patients compared with controls. Patients were also shown to have a significant increase in CD4+ T cells expressing the activation markers CD25 (P < 0.05) and HLA-DR (P < 0.01). Furthermore, serum levels of sIL-2R were significantly higher (P < 0.001) in patients than in controls. We also observed that the T-cell response was more pronounced in patients without simvastatin treatment (n = 18) compared with simvastatin-treated patients (n = 20). In conclusion, our findings indicate that a continuous immune system activation takes place in patients with chronic angina pectoris, predominantly involving proliferation of CD4+ T cells. Statin treatment seems to be able to decrease this inflammatory response.

Wild-type apolipoprotein A-I (apo A-I)-derived amyloid commonly occurs in atherosclerotic plaques. To clarify apo A-I amyloid formation, plasma levels of apo A-I and cholesterol were related to the presence of amyloid in atherosclerotic plaques in 15 patients with peripheral atherosclerosis, subjected to arterial reconstruction. Plasma levels of apo A-I and high-density lipoprotein (HDL) cholesterol were slightly higher in patients with apo A-I-derived amyloid than in those without, but the difference was not significant. Levels of low-density lipoprotein cholesterol and total cholesterol were significantly higher in the group with amyloid. High concentrations of apo A-I in the arterial intima are probably of greater importance to amyloid formation than high plasma levels of the protein. During atherosclerosis, the acute phase reactant serum amyloid A may displace apo A-I from HDL, leading to increased concentration of lipid-free apo A-I in the intima and conformational changes of apo A-I, which make it more fibrillogenic. Some forms of amyloid fibrils have been shown to be cytotoxic. Apo A-I-derived amyloid is possibly a pathogenically important factor in atherosclerosis.

In some respects, atherosclerosis resembles autoimmune disease. Since many autoimmune diseases are associated with certain histocompatibility leukocyte antigen (HLA) class II alleles, we have looked for a similar HLA association with atherosclerosis. In the first phase, genomic typing was performed in 52 men with coronary artery disease. In the second phase, 50 men with early onset (before 50 years of age) coronary artery disease were studied. 12 DRB1 and 4 DQB1 alleles were determined by restriction fragment length polymorphism analysis. No significant difference in frequency of the examined alleles was observed in any of the patient groups compared to healthy controls. The plasma level of lipoprotein(a) (Lp(a)) is considered an important risk factor for early coronary heart disease. A linkage between inherited high levels of Lp(a) and certain HLA class II genotypes has been suggested. In the present study, Lp(a) levels were measured in men with early onset of coronary artery disease. 11 (23%) Study patients and 3 (7%) control subjects had Lp(a) levels above 450 mg/l. However, no correlation between high Lp(a) levels and certain HLA genotypes was found. Summarized, these findings indicate that atherosclerosis, especially early onset coronary atherosclerosis, is not a disease associated with particular HLA alleles.

This paper presents a case of typical hyperlipoproteinemia type I in a young woman. Her serum triglycerides varied between 2 and 90 mmol/l and she had substantial amounts of apolipoprotein B-48 in fasting plasma. She had no detectable lipoprotein lipase (LPL) activity in post-heparin plasma (less than 0.2 percent of normal). Southern blot analysis suggested no major defect in her LPL gene and Northern blot analysis of adipose tissue RNA showed normal-sized LPL-mRNA. A 2-h [35S]methionine incorporation experiment with adipose tissue pieces in vitro showed that she produced normal-sized LPL and had LPL catalytic activity in the tissue. The amounts were, however, only 5-10% of control. No detectable LPL radioactivity or catalytic activity was released from patient tissue even in the presence of heparin in the incubations. Immunofluorescent staining of adipose tissue biopsies from the patient showed LPL immunoreactivity only in adipocytes and little or none within the capillaries. Treatment of immunoprecipitated labeled LPL with endoglycosidase H showed that the oligosaccharide chains on her enzyme were of the high-mannose type and not processed as in controls. Taken together the data suggest that the patient synthesizes a relatively normal LPL protein which is core-glycosylated and folded into active enzyme as in normal subjects, but is not effectively transported via the Golgi to the cell surface.

Lipoprotein lipase (LPL) (EC 3.1.1.34) hydrolyzes triacylglycerols of very low density lipoproteins and chylomicrons. It is produced by several cell types, including macrophages, which are frequent in atherosclerotic lesions. The atherosclerotic plaque also contains activated T lymphocytes. We therefore investigated the possible regulatory effect of the T lymphocyte-derived lymphokine interferon-gamma (IFN-gamma) on macrophage LPL. Human monocyte-derived macrophages were treated with recombinant IFN-gamma or conditioned medium from activated peripheral blood mononuclear cells for 3 days. LPL activity was thereafter measured in the culture medium and in cell homogenates. The enzyme protein was detected at a cellular level by immunocytochemistry and immunopredicipitation. Recombinant IFN-gamma caused a profound decrease in macrophage LPL secretion. The IFN-gamma-treated cells, however, still contained immunodetectable enzyme and the decrease in secretion was apparently only partly due to an inhibited synthesis. Conditioned medium from activated peripheral blood mononuclear cells also drastically decreased the macrophage LPL secretion. When the conditioned medium was treated with antibodies against IFN-gamma, its down-regulating effect on macrophage LPL was totally removed. The data indicate that IFN-gamma is inhibiting macrophage LPL at least in part via a reduction of LPL synthesis. A local release of IFN-gamma may be important in the pathogenesis of atherosclerosis by affecting the lipid accumulation in the lesion.

To summarize, it is possible that T cell activation in the plaque has four different effects: a direct inhibition of smooth muscle proliferation mediated by IFN-gamma, an indirect stimulation of smooth muscle proliferation via IFN-induced macrophage activation, an induction of responsiveness to PDGF by induction of PDGF receptor expression, and finally, an up-regulation of HDL receptors. The net effect of T cell activation during the vascular response to injury may, therefore, depend on the balance between these mechanisms in any given situation during lesion development. T cell activation may itself be regulated by apolipoprotein E-containing LDL, which thus could form a direct link between lipoprotein accumulation and immune activation. We have recently tried to assess the effect of T cell activation during the response to experimental arterial injury with the use of a drug model. Cyclosporin A is a drug that specifically inhibits T cell activation. Rats treated with cyclosporin A for a short period had significantly smaller intimal lesions than did controls after balloon injury. This could be due to an inhibition of T cell activation, resulting in an inhibition of monocyte-macrophage activation and thereby loss of an important stimulus for intimal cell proliferation. When interpreting these results, one must, however, bear in mind that cyclosporin A could exert as yet unknown nonimmune vascular effects. It is also worth stressing that cell proliferation in the human atherosclerotic plaque may not be as high as in experimental animal lesions. In fact, cell replication may be a very rare event in the average advanced atherosclerotic plaque. Cell proliferation may, however, be associated with an episodic growth of lesions, and growth factor-mediated responses could, therefore, be important for the eventual clinical outcome in the individual patient. In conclusion, cytokines produced during the immune response affect growth and differentiation of vascular cells and could modulate both the response to injury and the local lipid metabolism in an atherosclerotic plaque There is indirect support for paracrine secretion of several of these factors in the atherosclerotic plaque, and activated T lymphocytes and macrophages are abundant in the plaque. This points to the possibility that specific immune responses are associated with the development of atherosclerosis. It is unknown, however, to what extent such immune responses occur or which antigens may elicit these responses.

The cellular composition of human atherosclerotic plaques was analyzed by immunologic techniques. Plaques were removed from the internal carotid artery during surgery, and a panel of monoclonal antibodies was used to identify cell types. Macrophages stained by Anti-Leu-M3 were found throughout the plaque, particularly in the lipid core region, where 60% of the cells reacted with this antibody. T cells expressing the T3 antigen were most abundant in the fibrous cap, where they constituted 20% of the cell population. T cells were also isolated from the plaque and detected by a rosetting test; many of these T cells were activated, as indicated by the expression of HLA-DR. Other types of leukocytes were uncommon in the plaque. An antibody to the intermediate filament protein, desmin, was used as a marker for smooth muscle cells since some, but not all, vascular smooth muscle cells contain this protein. The desmin-positive cells were uncommon in the nonatherosclerotic intima but were more numerous in the plaque. In conclusion, atherosclerotic plaques are heterogeneous with respect to cellular composition. The smooth muscle cell dominates in the fibrous cap, which also contains many T cells; the lipid core is dominated by macrophages. We suggest that interactions between smooth muscle cells and blood-borne cells are important in the pathogenesis of atherosclerosis.

The arterial response to injury is dominated by proliferation of smooth muscle cells and infiltration of blood-borne cells in the vascular intima. Arterial smooth muscle cell proliferation is under growth factor control, but how this regulation operates in vivo is unclear. We studied the effect on arterial response to mechanical injury of cyclosporin A, a drug that inhibits T-lymphocyte activation. Cyclosporin A treatment at surgery caused a persistent inhibition of the intimal proliferative lesion. Cyclosporin A also inhibited expression of Ia antigens on smooth muscle cells in situ but had no direct effects on smooth muscle cell proliferation in culture. Therefore, the inhibition of intimal cell proliferation appears to be mediated via the immune system.

Class II antigens of the major histocompatibility complex (MHC) are normally expressed only by cells of the immune system. They may, however, also appear on other cells, both in vivo and in vitro. We have studied class II MHC antigen expression on human arterial smooth muscle cells using immunocytochemical analysis of surgical biopsies. The class II antigens, HLA-DQ and HLA-DR are virtually absent from cells of normal arteries, but appear in atherosclerotically transformed tissue, where the majority of cells express HLA-DR, and one-third of the cells express HLA-DQ. These atherosclerotic plaques are composed of a heterogeneous population of cells, which includes smooth muscle cells, macrophages, and T cells. Among smooth muscle cells containing the muscle-specific intermediate filament protein desmin, one-third of the cells express HLA-DR and almost as many express HLA-DQ. These cells also contain the invariant gamma chain, which is associated with class II antigens during intracellular transport. Plaque macrophages, in contrast, are usually of the DQ-DR+ phenotype. The patterns of class II antigen expression are discussed in relation to cell differentiation and pathogenesis of disease.

It was recently shown that the human atherosclerotic plaque contains significant amounts of T lymphocytes, and also that smooth muscle cells in these plaques express class II MHC (Ia) antigens. These antigens are not normally present on smooth muscle cells but are inducible by interferon-gamma, a secretory product of activated T cells. Therefore, T cell activation in the plaque was analyzed by immunofluorescent detection of activation markers on T cells isolated from the plaques and in cryostat sections of carotid endarterectomy specimens. Of cells isolated from the plaque, 5% exhibited the E rosettes characteristic of T cells. One third of these cells expressed HLA-DR and VLA-1 (very late activation antigen-1), which in T cells are synthesized only in the activated state. T cells were also identified in sections using immunofluorescent detection of the T cell-specific surface protein, CD3 (Leu-4), with rhodamine labeled second-step antibodies. The frequency of activated T cells was then determined by staining the same, or serial, sections with antibodies to HLA-DR or to the interleukin-2 receptor, followed by biotin-avidin-FITC detection. Of the T cells in the plaque, 34% and 6%, respectively, expressed these cell surface proteins. Taken together, these results indicated that a substantial proportion of the T cells in atherosclerotic plaque are in an activated state. The activation pattern, with a high frequency of HLA-DR and VLA-1 expression and a much lower frequency of interleukin-2 receptor expression, was similar to that reported to occur in chronic inflammatory conditions. Interferon-gamma could be detected in and around some of the lymphocytes, suggesting that paracrine secretion of this lymphokine may occur in the plaque. T cells may be activated locally, presumably by antigen(s) presented in the context of class II MHC expressing smooth muscle cells and/or macrophages, in the atherosclerotic lesion. Such activated T cells may in turn modulate the functions of other cells in the plaque.

The atherosclerotic plaque is composed of vascular smooth muscle cells and of macrophages and lymphocytes derived from the blood. We have recently shown that smooth muscle cells express class II MHC (Ia) antigens in the atherosclerotic plaque but not in the normal vessel wall. In the present study, we have tested whether there is a relationship between arterial injury and smooth muscle Ia expression. Rat carotid arteries were deendothelialized with a balloon catheter, and the rat Ia antigens, I-A and I-E, were detected by immunocytochemistry. Leukocytes and smooth muscle cells were identified by monoclonal antibodies to cell type-specific antigens. Normal rat carotids were always I-A and I-E negative, but approximately 10% of the cells became I-A-positive and 5% I-E positive during the response to injury. Ia expression was limited to non-replicating smooth muscle cells, suggesting that Ia is expressed as part of an activation response in a nondividing subfraction of the cells. The frequency of Ia-positive smooth muscle cells was maximal at 2 weeks postinjury, which coincided with maximal leukocyte infiltration and with the appearance of T lymphocytes in the neointima. This suggests that T cells induce Ia expression in smooth muscle cells. This was confirmed in cell culture experiments, where conditioned media from activated T lymphocytes induced Ia antigens in arterial smooth muscle cells. A similar induction of Ia expression was induced by recombinant gamma interferon, suggesting that this lymphokine may be responsible for smooth muscle Ia expression also in vivo.

The complete sequences of the yeast a mating-type locus, MATa, and of the silent alpha cassette, HML alpha, have been determined. A segment of 642 nucleotides is unique to MATa, and a corresponding segment of 747 nucleotides is unique to MAT alpha. The major mRNAs (a1, a2, alpha 1 and alpha 2) encoded by MATa and MAT alpha have been aligned with the DNA sequence. The a1 mRNA is encoded entirely within the a-specific DNA sequence. The a2 mRNA, which is transcribed divergently from a1 mRNA, is encoded in a region common to both Mata and Mat alpha. The alpha 1 and alpha 2 mRNAs are also transcribed divergently and have their 5' starts about 240 nucleotides apart within the alpha-specific sequence. The amino acid sequences of the MAT proteins have been predicted from the DNA sequences. An unanticipated conclusion is that the a1 protein, containing 148 amino acids, results from readthrough of a UGA at codon 45. Polymorphic forms of the homologous outer segments of the HML alpha, MAT alpha, MATa and HMRa sequences suggest that the boundaries of the segments involved in mating-type switching are immediately adjacent to the a-specific and alpha-specific sequences.

Several recent studies demonstrate that T lymphocytes and monocytes enter the vessel wall during pathologic conditions and accumulate both in atherosclerotic and arteritic lesions. This brief review summarizes our phenotypic analysis of such T lymphocytes. Effects of T lymphocytes and their secretory products (lymphokines) on vascular cells are discussed on the basis of both cell culture studies and animal experiments. Finally, the role of complement activation for recruitment of blood-borne cells is evaluated.