Combined transesophageal and surface MRI provides optimal imaging in aortic atherosclerosis.

OBJECTIVE: Surface magnetic resonance imaging (MRI) for aortic plaque assessment is limited by the trade-off between penetration depth and signal-to-noise ratio (SNR). For imaging the deep seated aorta, a combined surface and transesophageal MRI (TEMRI) technique was developed 1) to determine the individual contribution of TEMRI and surface coils to the combined signal, 2) to measure the signal improvement of a combined surface and TEMRI over surface MRI, and 3) to assess for reproducibility of plaque dimension analysis. METHODS AND RESULTS: In 24 patients six black blood proton-density/T2-weighted fast-spin echo images were obtained using three surface and one TEMRI coil for SNR measurements. Reproducibility of plaque dimensions (combined surface and TEMRI) was measured in 10 patients. TEMRI contributed 68% of the signal in the aortic arch and descending aorta, whereas the overall signal gain using the combined technique was up to 225%. Plaque volume measurements had an intraclass correlation coefficient of as high as 0.97. CONCLUSION: Plaque volume measurements for the quantification of aortic plaque size are highly reproducible for combined surface and TEMRI. The TEMRI coil contributes considerably to the aortic MR signal. The combined surface and TEMRI approach improves aortic signal significantly as compared to surface coils alone. CONDENSED ABSTRACT: Conventional MRI aortic plaque visualization is limited by the penetration depth of MRI surface coils and may lead to suboptimal image quality with insufficient reproducibility. By combining a transesophageal MRI (TEMRI) with surface MRI coils we enhanced local and overall image SNR for improved image quality and reproducibility.

Late diagnosis and vulnerabilities of the elderly living with HIV/AIDS

OBJECTIVE To identify vulnerabilities of elderly people with HIV/AIDS and the trajectory that they follow until reaching the diagnosis of the disease. METHOD Qualitative research conducted in specialized clinics in the state of São Paulo, from January to June 2011. Semi-structured interviews were conducted with 11 elderly people who were found to be infected with the virus at the age of 60 years or older. The interviews were analyzed using content analysis. RESULTS In this process four categories emerged, then analyzed with reference to the theoretical framework of vulnerability. CONCLUSION Late diagnosis of HIV infection or AIDS among the elderly happens in the secondary or tertiary service. Issues related to sexual life of the elderly are only questioned by health professionals after the diagnosis, also the time that condom use becomes absolute. It is believed that the investigation of the vulnerability of the elderly to HIV/AIDS allows for carrying out appropriate interventions for this population.

Effect of age on intraoperative cerebrovascular autoregulation and near-infrared spectroscopy-derived cerebral oxygenation.

Background. Age is an important risk factor for perioperative cerebral complications such as stroke, postoperative cognitive dysfunction, and delirium. We explored the hypothesis that intraoperative cerebrovascular autoregulation is less efficient and brain tissue oxygenation lower in elderly patients, thus, increasing the vulnerability of elderly brains to systemic insults such as hypotension.Methods. We monitored intraoperative cerebral perfusion in 50 patients aged 18-40 and 77 patients >65 yr at two Swiss university hospitals. Mean arterial pressure (MAP) was measured continuously using a plethysmographic method. An index of cerebrovascular autoregulation (Mx) was calculated based on changes in transcranial Doppler flow velocity due to changes in MAP. Cerebral oxygenation was assessed by the tissue oxygenation index (TOI) using near-infrared spectroscopy. End-tidal CO(2), O(2), and sevoflurane concentrations and peripheral oxygen saturation were recorded continuously. Standardized anaesthesia was administered in all patients (thiopental, sevoflurane, fentanyl, atracurium).Results. Autoregulation was less efficient in patients aged >65 yr [by 0.10 (SE 0.04; P=0.020)] in a multivariable linear regression analysis. This difference was not attributable to differences in MAP, end-tidal CO2, or higher doses of sevoflurane. TOI was not significantly associated with age, sevoflurane dose, or Mx but increased with increasing flow velocity [by 0.09 (SE 0.04; P=0.028)] and increasing MAP [by 0.11 (SE 0.05; P=0.043)].Conclusions. Our results do not support the hypothesis that older patients' brains are more vulnerable to systemic insults. The difference of autoregulation between the two groups was small and most likely clinically insignificant.

Focal dependent pleural thickening at MDCT: pleural lesion or functional abnormality?

PURPOSE: To describe the characteristics of reversible focal pleural thickenings (PTs) mimicking real plaques, that firstly suggest asbestos exposure or pleural metastasis; to propose an imaging strategy and propose an explanation for their mechanism of formation. PATIENTS AND METHODS: Retrospective review of data from 19 patients with PTs fitting the description of pleural plaques at chest computed tomography (CT) and presenting modifications (clearance or appearance) of at least one PT at an additional chest examination in prone position. RESULTS: A total of 152 PTs were recorded on the first chest CT examinations with a range of two to 19 pleural opacities per patient. All PTs had a posterior distribution in the lower lobes. On the additional acquisitions, 144 PTs disappeared. Seventeen patients presented complete regression of PTs and two patients presented persistence of eight PTs. CONCLUSION: Additional low dose acquisition in prone position should be performed in all patients presenting with focal PT in a dependent and basal location. This may allow to exclude a pleural plaque in case of asbestos exposure but also a pleural metastasis in oncologic patients. These reversible dependent PTs could be related to physiological focal accumulation of lymphatic fluid in subpleural area.

The Pseudomonas aeruginosa toxin L-2-amino-4-methoxy-trans-3-butenoic acid inhibits growth and induces encystment in Acanthamoeba castellanii.

L-2-Amino-4-methoxy-trans-3-butenoic acid (AMB) is a toxic antimetabolite produced by the opportunistic pathogen Pseudomonas aeruginosa. To evaluate its importance as a potential virulence factor, we tested the host response towards AMB using an Acanthamoeba castellanii cell model. We found that AMB (at concentrations ≥ 0.5 mM) caused amoebal encystment in salt buffer, while inhibiting amoebal growth in rich medium in a dose-dependent manner. However, no difference in amoebal plaque formation was observed on bacterial lawns of wild type and AMB-negative P. aeruginosa strains. We thereby conclude that AMB may eventually act as a virulence factor, but only at relatively high concentrations.

PPARgamma but not PPARalpha ligands are potent repressors of major histocompatibility complex class II induction in atheroma-associated cells.

Peroxisome proliferator-activated receptors (PPARs) are essential in glucose and lipid metabolism and are implicated in metabolic disorders predisposing to atherosclerosis, such as diabetes and dyslipidemia. Conversely, antidiabetic glitazones and hypolipidemic fibrate drugs, known as PPARgamma and PPARalpha ligands, respectively, reduce the process of atherosclerotic lesion formation, which involves chronic immunoinflammatory processes. Major histocompatibility complex class II (MHC-II) molecules, expressed on the surface of specialized cells, are directly involved in the activation of T lymphocytes and in the control of the immune response. Interestingly, expression of MHC-II has recently been observed in atherosclerotic plaques, and it can be induced by the proinflammatory cytokine interferon-gamma (IFN-gamma) in vascular cells. To explore a possible role for PPAR ligands in the regulation of the immune response, we investigated whether PPAR activation affects MHC-II expression in atheroma-associated cells. In the present study, we demonstrate that PPARgamma but not PPARalpha ligands act as inhibitors of IFN-gamma-induced MHC-II expression and thus as repressors of MHC-II-mediated T-cell activation. All different types of PPARgamma ligands tested inhibit MHC-II. This effect of PPARgamma ligands is due to a specific inhibition of promoter IV of CIITA and does not concern constitutive expression of MHC-II. Thus, the beneficial effects of antidiabetic PPARgamma activators on atherosclerotic plaque development may be partly explained by their repression of MHC-II expression and subsequent inhibition of T-lymphocyte activation.

Understanding child neglect in a gender context: a study performed in a Brazilian city

OBJECTIVETo describe the phenomenon of child neglect and understand it in a gender context.METHODRetrospective, quantitative, and exploratory study that analyzed reports of violence by a child and adolescent protection network in a Brazilian city. The theoretical and methodological basis applied was TIPESC (Theory of Nursing Praxical Intervention in Collective Health), with a gender emphasis.RESULTSNeglect of children under the age of ten represents more than half the reports received over all the years studied; more boys than girls suffered neglect and 41.4% of the reports of neglect involved children under than age of three; women were identified as being solely responsible in 67.9%, and as accessories in 17.3% of the incidents reported.CONCLUSIONChild neglect is a complex matter, the gender subordinate status inflicted on these children and their mothers who are responsible for their care underscore the social vulnerability of this group.

Setting up a Common European Asylum System : Report on the application of existing instruments and proposals for the new system

The study assesses firstly the evaluation process of the first generation of asylum instruments while underlining the possibilities to improve it. It analyses secondly the asylum "acquis" regarding distribution of refugees between Member States, the eligibility for protection, the status of protected persons regarding detention and vulnerability, asylum procedures and the external dimension by formulating short-term recommendations of each area. Its last part is devoted to the long term evolution of the Common European Asylum System regarding the legal context including the accession of the EU to the Geneva Convention, the institutional perspectives including the new European Support Office, the jurisdictional perspective, the substantive perspective, the distributive perspective and the external perspective.

Impaired glutathione synthesis in schizophrenia: convergent genetic and functional evidence

Schizophrenia is a complex multifactorial brain disorder with a genetic component. Convergent evidence has implicated oxidative stress and glutathione (GSH) deficits in the pathogenesis of this disease. The aim of the present study was to test whether schizophrenia is associated with a deficit of GSH synthesis. Cultured skin fibroblasts from schizophrenia patients and control subjects were challenged with oxidative stress, and parameters of the rate-limiting enzyme for the GSH synthesis, the glutamate cysteine ligase (GCL), were measured. Stressed cells of patients had a 26% (P = 0.002) decreased GCL activity as compared with controls. This reduction correlated with a 29% (P < 0.001) decreased protein expression of the catalytic GCL subunit (GCLC). Genetic analysis of a trinucleotide repeat (TNR) polymorphism in the GCLC gene showed a significant association with schizophrenia in two independent case-control studies. The most common TNR genotype 7/7 was more frequent in controls [odds ratio (OR) = 0.6, P = 0.003], whereas the rarest TNR genotype 8/8 was three times more frequent in patients (OR = 3.0, P = 0.007). Moreover, subjects with disease-associated genotypes had lower GCLC protein expression (P = 0.017), GCL activity (P = 0.037), and GSH contents (P = 0.004) than subjects with genotypes that were more frequent in controls. Taken together, the study provides genetic and functional evidence that an impaired capacity to synthesize GSH under conditions of oxidative stress is a vulnerability factor for schizophrenia.

Neuroticism modifies psychophysiological responses to fearful films

Background: Neuroticism is a personality component frequently found in anxious and depressive psychiatric disorders. The influence of neuroticism on negative emotions could be due to its action on stimuli related to fear and sadness, but this remains debated. Our goal was thus to better understand the impact of neuroticism through verbal and physiological assessment in response to stimuli inducing fear and sadness as compared to another negative emotion (disgust).¦Methods: Fifteen low neurotic and 18 high neurotic subjects were assessed on an emotional attending task by using film excerpts inducing fear, disgust, and sadness. We recorded skin conductance response (SCR) and corrugator muscle activity (frowning) as indices of emotional expression.¦Results: SCR was larger in high neurotic subjects than in low neurotics for fear relative to sadness and disgust. Moreover, corrugator activity and SCR were larger in high than in low neurotic subjects when fear was induced.¦Conclusion: After decades of evidence that individuals higher in neuroticism experience more intense emotional reactions to even minor stressors, our results indicate that they show greater SCR and expressive reactivity specifically to stimuli evoking fear rather than to those inducing sadness or disgust. Fear processing seems mainly under the influence of neuroticism. This modulation of autonomic activity by neurotics in response to threat/fear may explain their increased vulnerability to anxious psychopathologies such as PTSD (post traumatic stress disorder).

High prevalence of peripheral atherosclerosis in a rapidly developing country.

Cardiovascular disease is rapidly increasing in developing countries experiencing epidemiological transition. We investigated the prevalence of peripheral atherosclerosis in a rapidly developing country and compared our findings with data previously reported in Western populations. A cardiovascular risk factor survey was conducted in 1067 individuals aged 25-64 randomly selected from the general population of Seychelles. High-resolution ultrasonography of the right and left carotid and femoral arteries was performed in a random subgroup of 503 subjects (245 men and 258 women). In each of the four arteries, arterial wall thickness (in plaque-free segments) and atherosclerotic plaques (i.e. focal wall thickening at least 1.0 mm thick) were measured separately. The prevalence of peripheral atherosclerosis was high in this population. For instance, at least one plaque > or =1.0 mm was found in, respectively, 34.9 and 27.5% of men and women aged 25-34 and at least one plaque > or =2.5 mm was found in, respectively, 58.2 and 36.9% of men and women aged 55-64. With reference to data found in the literature, the prevalence of carotid atherosclerosis appeared to be significantly higher in Seychelles than in Western populations. This study provides further evidence for the importance of cardiovascular disease in developing countries. Determinants should be identified and relevant prevention and control programs implemented.

Lésions endothéliales des ballons de contre-pulsion intra-aortique [Endothelial lesions caused by intra-aortic counterpulsation balloons]

Intra-aortic balloon pump (IABP) is the most frequently used mechanical circulatory support. Repeated trauma on the aortic wall has been reported as a cause of balloon perforation by endothelial denudation of atheromatous plaque. This study analyses the effect of IABP on the endothelium of the calf aorta. In 12 calves (mean weight: 72 +/- 6 kg) an IABP was inserted by femoral route and left during 6 hours on internal mode with a frequency of 80 cycles/min. The animals were sacrificed after the procedure (n = 4), at postoperative day (POD) 7 (n = 4), and at POD 14 (n = 4). In the aorta facing the balloon, nine transmural samples were taken proximally (n = 3), at mid height (n = 3) and distally (n = 3), for histological analysis of the percentage of aortic surface covered with endothelium. The percentage of aortic surface covered with endothelium at POD 0, 7 and 14 was proximally: 72.5 +/- 27.5%, 83.7 +/- 16.9% and 93.3 +/- 8.9% respectively; at mid-height: 50.8 +/- 30.7%, 65 +/- 25% and 95 +/- 5%; and distally: 31.4 +/- 20.1%, 48.3 +/- 34.4% and 85 +/- 10%. A large portion of the aortic endothelium is abraded after 6 hours of IAB pumping. This effect is more important at the distal level of the aorta. After two weeks, most of the endothelium has regenerated.

Clustering of health behaviours in adult survivors of childhood cancer and the general population.

BACKGROUND: Little is known about engagement in multiple health behaviours in childhood cancer survivors. METHODS: Using latent class analysis, we identified health behaviour patterns in 835 adult survivors of childhood cancer (age 20-35 years) and 1670 age- and sex-matched controls from the general population. Behaviour groups were determined from replies to questions on smoking, drinking, cannabis use, sporting activities, diet, sun protection and skin examination. RESULTS: The model identified four health behaviour patterns: 'risk-avoidance', with a generally healthy behaviour; 'moderate drinking', with higher levels of sporting activities, but moderate alcohol-consumption; 'risk-taking', engaging in several risk behaviours; and 'smoking', smoking but not drinking. Similar proportions of survivors and controls fell into the 'risk-avoiding' (42% vs 44%) and the 'risk-taking' cluster (14% vs 12%), but more survivors were in the 'moderate drinking' (39% vs 28%) and fewer in the 'smoking' cluster (5% vs 16%). Determinants of health behaviour clusters were gender, migration background, income and therapy. CONCLUSION: A comparable proportion of childhood cancer survivors as in the general population engage in multiple health-compromising behaviours. Because of increased vulnerability of survivors, multiple risk behaviours should be addressed in targeted health interventions.

Psychogenic seizures and frontal disconnection: EEG synchronisation study.

Objective Psychogenic non-epileptic seizures (PNES) are paroxysmal events that, in contrast to epileptic seizures, are related to psychological causes without the presence of epileptiform EEG changes. Recent models suggest a multifactorial basis for PNES. A potentially paramount, but currently poorly understood factor is the interplay between psychiatric features and a specific vulnerability of the brain leading to a clinical picture that resembles epilepsy. Hypothesising that functional cerebral network abnormalities may predispose to the clinical phenotype, the authors undertook a characterisation of the functional connectivity in PNES patients. Methods The authors analysed the whole-head surface topography of multivariate phase synchronisation (MPS) in interictal high-density EEG of 13 PNES patients as compared with 13 age- and sex-matched controls. MPS mapping reduces the wealth of dynamic data obtained from high-density EEG to easily readable synchronisation maps, which provide an unbiased overview of any changes in functional connectivity associated with distributed cortical abnormalities. The authors computed MPS maps for both Laplacian and common-average-reference EEGs. Results In a between-group comparison, only patchy, non-uniform changes in MPS survived conservative statistical testing. However, against the background of these unimpressive group results, the authors found widespread inverse correlations between individual PNES frequency and MPS within the prefrontal and parietal cortices. Interpretation PNES appears to be associated with decreased prefrontal and parietal synchronisation, possibly reflecting dysfunction of networks within these regions.

Epiphytic lichens as surrogates for biodiversity and ecosystem resilience in native oakwoods of the Baixo Tamega region (Northern Portugal)

In the last 50 years, concern about the loss of lichen diversity associated with forest management and forest fragmentation has led to many studies designed to assess patterns and monitor trends of lichen biodiversity in forests worldwide. However there are surprisingly few studies focusing on the effect of natural disturbance for epiphytic lichens in forest ecosystems and, especially, on how these changes affect the relationships between epiphytic lichens and other organisms. The major goal of this thesis was to characterize and valuate the epiphytic lichens in the Baixo Tamega region (northern Portugal) and to assess its vulnerability to several drivers of change, particularly fire. The study area is located in Aboboreira and Castelo, a mountain area with 105 km2 and a top altitude of approximately 1000 m.a.s.l. In this region, fire is one of the worst natural catastrophes not only because of its high frequency and wide extension but also because of their enormous destructive effects. This thesis has included three case studies that proved the need to develop management and conservation actions for the area. In the first study we assessed the epiphytic lichen diversity in the oak woods of the Aboboreira and Castelo mountains. Results have revealed high diversity value and presence of a lichen community that has suffered general decline throughout Europe. The second study has addressed the impact of fire over epiphytic lichens and community recovering patterns. Results observed along the fire gradient showed that the most common and abundant lichen species establish themselves early in post-fire gradient while “old-growth” associated lichens tend to recover slowly along the same gradient. The third study intended to evaluate the potential use of selected lichen species or groups as biodiversity surrogates, in a scenario of fire-controlled ecological changes. Results showed that the use of epiphytic lichens as surrogates of bryophyte and vascular plant diversity should consider not only species richeness and composition, but also occurrence of disturbing factors, such fire. among the studied groups, lichen genera is the only group that can be used as surrogate of total epiphytic lichen diversity, independently of fire induced changes