Subcortical and cortical gray matter differences between Kraepelinian and non-Kraepelinian schizophrenia patients identified using voxel-based morphometry

The long-term outcome of schizophrenia patients may differ depending on their brain structure. This would be reflected in significant structural differences between poor-outcome (i.e., Kraepelinian) and non-Kraepelinian patients. To assess this possibility, we have evaluated the degree of deviation in brain structure in Kraepelinian patients with respect to controls and non-Kraepelinian schizophrenia patients. We used voxel-brain morphometry (VBM) to assess the differences in gray matter volume across the brain in the Kraepelinian group with respect to the healthy controls and non-Kraepelinian patients. Twenty-six Kraepelinian and 18 non-Kraepelinian schizophrenia patients and 41 healthy controls were included. With respect to the healthy controls, the Kraepelinian patients showed a very significant decrease in gray matter in the frontal, occipital, and limbic cortices, and, at a subcortical level, bilaterally in the striatum and thalamus. In comparison with the non-Kraepelinian patients, the Kraepelinian individuals continued to show a similar subcortical decrease. Thus, Kraepelinian patients may be characterized by a distinct pattern of brain abnormalities, in particular, in subcortical regions.

Multimodality imaging of chronic ischemia

Although ischemic cardiomyopathy is commonly caused by chronic obstructive coronary disease, the mechanism of the cause is still under investigation. We present echocardiographic strain, magnetic resonance, and histology findings in a chronic ischemia model in preclinical study. This case illustrates the features of multimodality imaging in chronic obstructive coronary disease and gives us great insight into understanding the mechanism of ischemic cardiomyopathy.

Anomalous origin of the three major coronary arteries from a single common ostium

The prevalence of coronary anomalies is about 1.3% among patients who undergo coronary angiography. Although the majority of coronary artery anomalies are incidental findings and are not clinically significant, the interarterial course between the great vessels of the aberrant artery may be responsible for syncope, angina, arrhythmias or sudden death. There are only a few case reports in the literature that describe the origin of all coronary arteries from a single ostium. This type of anomaly has been seen in only 0.024-0.044% of the population. This is a first case where not only was there a common ostium of the left anterior descending artery and right coronary artery without a left main, but an absent left circumflex artery with blood supply of its territory by a posterolateral/marginal branch from the right posterior descending artery and conal branch.

Intestinal current measurement for diagnostic classification of patients with questionable cystic fibrosis: validation and reference data

BACKGROUND

In questionable cystic fibrosis (CF), mild or monosymptomatic phenotypes frequently cause diagnostic difficulties despite detailed algorithms. CF transmembrane conductance regulator (CFTR)-mediated ion transport can be studied ex vivo in rectal biopsies by intestinal current measurement (ICM).

OBJECTIVES

To describe reference values and validate ICM for the diagnostic classification of questionable CF at all patient ages.

METHODS

ICM was performed in 309 rectal biopsies from 130 infants, children and adults including patients with known pancreatic-insufficient (PI)-CF (n=34), pancreatic-sufficient (PS)-CF (n=7), patients with an unclear diagnosis with mild CF symptoms, intermediate sweat test and/or CFTR mutation screening (n=61) and healthy controls (n=28). ICM was correlated to sweat chloride, extensive CFTR genotype and transcript analysis in the diagnostic group. The results were compared with previous ICM data in subjects with CF, congenital bilateral absence of the vas deferens, heterozygotes and controls.

RESULTS

The cumulative chloride secretory response of DeltaI(sc,carbachol), DeltaI(sc,cAMP/forskolin) and DeltaI(sc,histamine) was the best diagnostic ICM parameter (cut-off 34 muA/cm(2) between patients with known PS-CF and controls), differentiating patients with questionable CF into PS-CF (n=6) and 'CF unlikely' (n=55) groups. Extensive genotype analysis detected two mutations (40% disease-causing) in 100% of individuals classified as PS-CF compared with 1.8% in those classified as 'CF unlikely'.

CONCLUSIONS

This comprehensive investigation of CFTR function and genotype underlines the diagnostic value of ICM, especially for confirmation of CF in the absence of two disease-causing CFTR mutations, exclusion of CF despite intermediate sweat test and age groups unsuitable for nasal potential difference measurements. ICM is an important tool for functional assessment in CFTR mutations of unknown clinical relevance.

The BioImage Study: novel approaches to risk assessment in the primary prevention of atherosclerotic cardiovascular disease--study design and objectives

The identification of asymptomatic individuals at risk for near-term atherothrombotic events to ensure optimal preventive treatment remains a challenging goal. In the BioImage Study, novel approaches are tested in a typical health-plan population. Based on certain demographic and risk characteristics on file with Humana Inc, a total of 7,687 men 55 to 80 years of age and women 60 to 80 years of age without evidence of atherothrombotic disease but presumed to be at risk for near-term atherothrombotic events were enrolled between January 2008 and June 2009. Those who met the prespecified eligibility criteria were randomized to a telephonic health survey only (survey only: n = 865), standard risk assessment (Framingham only: n = 718), or comprehensive risk assessment in a dedicated mobile facility equipped with advanced imaging tools (n = 6,104). Baseline examination included assessment of cardiovascular risk factors and screening for subclinical (asymptomatic) atherosclerosis with quantification of coronary artery calcification by computed tomography (CT), measurement of intima-media thickness, presence of carotid atherosclerotic plaques and abdominal aortic aneurysm by ultrasound, and ankle brachial index. Participants with one or more abnormal screening test results underwent advanced imaging with contrast-enhanced magnetic resonance imaging for carotid and aortic plaques, contrast-enhanced coronary CT angiography for luminal stenosis and noncalcified plaques, and 18F-fluorodeoxyglucose-positron emission tomography/CT for carotid and aortic plaque inflammation. Plasma, PAXgene RNA, and DNA samples were obtained, frozen, and stored for future biomarker discovery studies. All individuals will be followed until 600 major atherothrombotic events have occurred in those undergoing imaging. The BioImage Study will help identify those patients with subclinical atherosclerosis who are at risk for near-term atherothrombotic events and enable a more personalized management of care.

Microvascular dysfunction in hypertrophic cardiomyopathy evaluated by cardiac magnetic resonance and computed tomography

A 36-year-old woman with hypertrophic cardiomyopathy (HCM) was referred for the evaluation of chest pain. A stress cardiac magnetic resonance showed severe hypertrophy of the anteroseptal wall with severe ischaemia induced after adenosine infusion. LV size and function were normal. On delayed enhancement imaging, extensive, patchy areas of hyperenhancement in the hypertrophic segments were observed. A 64-slice computed tomography scan showed no evidence of significant coronary disease. Microvascular dysfunction in HCM may be a predisposing factor for myocardial ischaemia, leading to an increased risk of sudden death. However, the pathophysiological mechanisms remain largely unknown as well as whether the extension of the hypertrophy is associated with poor perfusion reserve. Non-invasive imaging modalities may be helpful in the identification of the underlying substrate determining the risk in these patients.

Spreading of persistent infections in heterogeneous populations

Up to now, the effects of having heterogeneous networks of contacts have been studied mostly for diseases which are not persistent in time, i.e., for diseases where the infectious period can be considered very small compared to the lifetime of an individual. Moreover, all these previous results have been obtained for closed populations, where the number of individuals does not change during the whole duration of the epidemics. Here, we go one step further and analyze, both analytically and numerically, a radically different kind of diseases: those that are persistent and can last for an individual's lifetime. To be more specific, we particularize to the case of tuberculosis' (TB) infection dynamics, where the infection remains latent for a period of time before showing up and spreading to other individuals. We introduce an epidemiological model for TB-like persistent infections taking into account the heterogeneity inherent to the population structure. This sort of dynamics introduces new analytical and numerical challenges that we are able to sort out. Our results show that also for persistent diseases the epidemic threshold depends on the ratio of the first two moments of the degree distribution so that it goes to zero in a class of scale-free networks when the system approaches the thermodynamic limit.

Implosion experiments using glass ablators for direct-drive inertial confinement fusion

Direct-drive implosions with 20-microm-thick glass shells were conducted on the Omega Laser Facility to test the performance of high-Z glass ablators for direct-drive, inertial confinement fusion. The x-ray signal caused by hot electrons generated by two-plasmon-decay instability was reduced by more than approximately 40x and hot-electron temperature by approximately 2x in the glass compared to plastic ablators at ignition-relevant drive intensities of approximately 1x10(15) W/cm2, suggesting reduced target preheat. The measured absorption and compression were close to 1D predictions. The measured soft x-ray production in the spectral range of approximately 2 to 4 keV was approximately 2x to 3x lower than 1D predictions, indicating that the shell preheat caused by soft x-rays is less than predicted. A direct-drive-ignition design based on glass ablators is introduced.

Voxel-based morphometry comparison between first episodes of psychosis with and without evolution to schizophrenia

First episodes (FE) of psychosis may evolve or not to schizophrenia in ensuing years, but there is a lack of reliable predictors of which patients will have to face such an unfavorable outcome. Given the replicated structural alterations of the brain in schizophrenia, it seems advisable to assess whether the alterations of this kind that can be detected at the time of an initial psychotic episode are different depending on the outcome of the patients. To this end, here we applied voxel-based morphometry to assess whether the degree of cerebral abnormalities differ between 30 FE patients who evolved to schizophrenia in the ensuing 2years and another 14 FE patients who could not be diagnosed as such during that period. Forty-one controls were also included in the study. We found that the FE patients who evolved to schizophrenia had a significantly lower GM value than the controls bilaterally in the left dorsolateral prefrontal (BA 9) and in left anterior cingulate (BA 33) regions while the FE patients who did not develop schizophrenia showed a distinct, right-sided pattern of deviation (visual cortex, superior temporal gyrus and inferior frontal). The direct comparison between FE patients who evolved or not evolved to schizophrenia did not reveal significant differences. Taken together, our results support the notion that brain abnormalities may be different in psychotic FE patients depending on their evolution in the medium term.

Imaging techniques and the evaluation of the right heart and the pulmonary circulation

Since the right side of the heart and the pulmonary circulation are regarded as secondary components of the circulatory system, their role in disease has traditionally not received the same attention as their counterparts in the systemic circulation. This was partly because precise noninvasive study of these structures was difficult. For many years, chest radiography and invasive angiography were the only techniques available for imaging the minor circulation. The development of transthoracic echocardiography and nuclear techniques has produced a significant leap forward for noninvasive imaging, particularly of the right ventricle. More recently, novel echocardiographic techniques, and advances in computed tomography and magnetic resonance imaging, in particular, have expanded our diagnostic armamentarium and provided new insights into the anatomy and function of the pulmonary circulation in both health and disease. This article contains a review of the current status of techniques for imaging the right side of the heart and the pulmonary circulation.

The cardioprotection granted by metoprolol is restricted to its administration prior to coronary reperfusion

BACKGROUND

Myocardial infarct size is a strong predictor of cardiovascular events. Intravenous metoprolol before coronary reperfusion has been shown to reduce infarct size; however, it is unknown whether oral metoprolol initiated early after reperfusion, as clinical guidelines recommend, is similarly cardioprotective. We compared the extent of myocardial salvage associated with intravenous pre-reperfusion-metoprolol administration in comparison with oral post-reperfusion-metoprolol or placebo. We also studied the effect on suspected markers of reperfusion injury.

METHODS

Thirty Yorkshire-pigs underwent a reperfused myocardial infarction, being randomized to pre-reperfusion-metoprolol, post-reperfusion-metoprolol or placebo. Cardiac magnetic resonance imaging was performed in eighteen pigs at day 3 for the quantification of salvaged myocardium. The amounts of at-risk and infarcted myocardium were quantified using T2-weighted and post-contrast delayed enhancement imaging, respectively. Twelve animals were sacrificed after 24h for reperfusion injury analysis.

RESULTS

The pre-reperfusion-metoprolol group had significantly larger salvaged myocardium than the post-reperfusion-metoprolol or the placebo groups (31 ± 4%, 13 ± 6%, and 7 ± 3% of myocardium at-risk respectively). Post-mortem analyses suggest lesser myocardial reperfusion injury in the pre-reperfusion-metoprolol in comparison with the other 2 groups (lower neutrophil infiltration, decreased myocardial apoptosis, and higher activation of the salvage-kinase phospho-Akt). Salvaged myocardium and reperfusion injury pair wise comparisons proved there were significant differences between the pre-reperfusion-metoprolol and the other 2 groups, but not among the latter two.

CONCLUSIONS

The intravenous administration of metoprolol before coronary reperfusion results in larger myocardial salvage than its oral administration initiated early after reperfusion. If confirmed in the clinical setting, the timing and route of β-blocker initiation could be revisited.

Noninvasive evaluation of a coronary-pulmonary artery fistula

Coronary angiography can be used to identify the size and anatomical features of coronaryartery fistulas (CAF), but it may fail to depict the drainage site of the CAF or its relation to other structures. In our case, the combined use of CT and CMR provided all the necessary information forclinical management.

Evaluation of cardiac valves using multidetector CT

Cardiac CT is an accurate and reasonable alternative modality for valvular imaging. It is used primarily for the evaluation of coronary artery disease; however, important information regarding valvular anatomy and function can be derived from CT. Calcification is a common CT finding in various valvular abnormalities and carries important diagnostic and prognostic value. In addition, valvular morphology, stenosis, and regurgitation also are detected on contrast enhanced scans, with good correlation with trans-thoracic echocardiography and other techniques.

[Visualizing arterial macrophage warfare with nuclear magnetic resonance, positron-emission tomography and computerized tomography]

The macrophage is the principal immune cell found in atherosclerotic plaque. Although its function is to phagocytose foreign bodies present in the vascular endothelium, it can undergo a process of sustained activation that gives rise to a pattern of chronic inflammation, which may even trigger an acute coronary syndrome. The cellular response underlying this disease process is mediated by a complex molecular signaling cascade. Cytokines released by activated macrophages ultimately produce significant tissue damage by perpetuating the ongoing inflammatory response. Recent studies have shown that a defective interaction between the macrophage and its substrate could provide a mechanism for destabilizing atherosclerotic plaque by stimulating digestion of the artery and promoting plaque rupture. A key element in the life cycle of macrophages is that, when they cannot effectively remove the foreign bodies that have resulted in their activation, they initiate cell death (i.e., apoptosis), thereby releasing substances into the extracellular milieu that are even more toxic than inflammatory mediators. The significant advances in noninvasive molecular imaging techniques that have taken place in recent years have helped to unravel fundamental features of macrophage biology and have made it possible to explore the potential benefits of specific therapeutic interventions. Nanomarkers designed to home in on specific molecular targets have enabled imaging techniques to be used not only to study the pathophysiological mechanisms of atherosclerotic disease but also to diagnose such disease, and have made it possible to imagine the development of a form of nanomedicine based on administering treatment that can target a single cell type.

The CFTR frameshift mutation 3905insT and its effect at transcript and protein level

Cystic fibrosis (CF) is one of the most common genetic diseases in the Caucasian population and is characterized by chronic obstructive pulmonary disease, exocrine pancreatic insufficiency, and elevation of sodium and chloride concentrations in the sweat and infertility in men. The disease is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, which encodes a protein that functions as chloride channel at the apical membrane of different epithelia. Owing to the high genotypic and phenotypic disease heterogeneity, effects and consequences of the majority of the CFTR mutations have not yet been studied. Recently, the frameshift mutation 3905insT was identified as the second most frequent mutation in the Swiss population and found to be associated with a severe phenotype. The frameshift mutation produces a premature termination codon (PTC) in exon 20, and transcripts bearing this PTC are potential targets for degradation through nonsense-mediated mRNA decay (NMD) and/or for exon skipping through nonsense-associated alternative splicing (NAS). Using RT-PCR analysis in lymphocytes and different tissue types from patients carrying the mutation, we showed that the PTC introduced by the mutation does neither elicit a degradation of the mRNA through NMD nor an alternative splicing through NAS. Moreover, immunocytochemical analysis in nasal epithelial cells revealed a significantly reduced amount of CFTR at the apical membrane providing a possible molecular explanation for the more severe phenotype observed in F508del/3905insT compound heterozygotes compared with F508del homozygotes. However, further experiments are needed to elucidate the fate of the 3905insT CFTR in the cell after its biosynthesis.