Assessment of factors that confound MRI and neuropathological correlation of human postmortem brain tissue

In spite of considerable technical advance in MRI techniques, the optical resolution of these methods are still limited. Consequently, the delineation of cytoarchitectonic fields based on probabilistic maps and brain volume changes, as well as small-scale changes seen in MRI scans need to be verified by neuronanatomical/neuropathological diagnostic tools. To attend the current interdisciplinary needs of the scientific community, brain banks have to broaden their scope in order to provide high quality tissue suitable for neuroimaging- neuropathology/anatomy correlation studies. The Brain Bank of the Brazilian Aging Brain Research Group (BBBABSG) of the University of Sao Paulo Medical School (USPMS) collaborates with researchers interested in neuroimaging-neuropathological correlation studies providing brains submitted to postmortem MRI in-situ. In this paper we describe and discuss the parameters established by the BBBABSG to select and to handle brains for fine-scale neuroimaging-neuropathological correlation studies, and to exclude inappropriate/unsuitable autopsy brains. We tried to assess the impact of the postmortem time and storage of the corpse on the quality of the MRI scans and to establish fixation protocols that are the most appropriate to these correlation studies. After investigation of a total of 36 brains, postmortem interval and low body temperature proved to be the main factors determining the quality of routine MRI protocols. Perfusion fixation of the brains after autopsy by mannitol 20% followed by formalin 20% was the best method for preserving the original brain shape and volume, and for allowing further routine and immunohistochemical staining. Taken to together, these parameters offer a methodological progress in screening and processing of human postmortem tissue in order to guarantee high quality material for unbiased correlation studies and to avoid expenditures by post-imaging analyses and histological processing of brain tissue.

Altered expression of the costimulatory molecules CD80, CD86, CD152, PD-1 and ICOS on T-cells from paracoccidioidomycosis patients: Lack of correlation with T-cell hyporesponsiveness

T-cell proliferative hypo responsiveness, a hallmark of paracoccidioidomycosis immune responses, underlies host`s failure in controlling fungus spread, being reversible with antifungal treatment. The mechanisms leading to this hypoproliferation are not well known. Since costimulatory molecules have been shown to profoundly regulate T-cell immune responses, we investigated the hypothesis that the determinants of the responder versus tolerant state may be the regulated expression of, or signaling by, costimulatory molecules. Expression of CD80, CD86, CD28, CD152, ICOS and PD-1 costimulatory molecules were examined on T-cells and monocytes harvested from stimulated and unstimulated PBMC cultures of active paracoccidioidomycosis patients and healthy individuals cured of past paracoccidioidomycosis. Stimuli were gp43, the immunodominant component of Paracoccidioides brasiliensis, and a Candida antigen. While CD28 expression, critical for optimal T-cell activation, was comparable between patients and controls, CD152, PD-1 and ICOS, which preferentially deliver negative signaling, were overexpressed on patients` stimulated and unstimutated T-cells. PBMC cultures were carried out in presence of the respective blocking antibodies which, however, failed to restore T-cell proliferation. CD80 and CD86 were equally expressed on patients` and controls` monocytes, but overexpressed on patients` T-cells. Blockade with the respective blocking antibodies on day 4 of the culture also did not restore T-cell proliferation, while, on day 0, differentially inhibited Candida and gp43 responses, suggesting that different antigens require different costimulatory pathways for antigen presentation. Our data favors the hypothesis, raised from other foreign antigen models, that prolonged in vivo antigen exposure leads to an adaptive tolerance T-cell state which is hardly reverted in vitro. (C) 2008 Elsevier Inc. All rights reserved.

Mitochondrial DNA depletion and its correlation with TFAM, TFB1M, TFB2M and POLG in human diffusely infiltrating astrocytomas

Mitochondrial DNA (mtDNA) alterations and their clinical and pathological implications have been analyzed in several human malignancies. A marked decrease in mtDNA copy number along with the increase in malignancy was observed in diffusely infiltrating astrocytomas (24 WHO grade II, 18 grade III, and 78 grade IV or GBM) compared to non-neoplastic brain tissues, being mostly depleted in GBM. Although high relative gene expression levels of mtDNA replication regulators (mitochondrial polymerase catalytic subunit (POLG), transcription factors A (TFAM), B1 (TFB1M) and B2 (TFB2M)) were detected, it cannot successfully revert the mtDNA depletion observed in our samples. On the other hand, a strong correlation among the expression levels of mitochondrial transcription factors corroborates with the TFAM role in the direct control of TFB1M and TFB2M during initiation of mtDNA replication. POLG expression was related to decreased mtDNA copy number, and its overexpression associated with TFAM expression levels also have an impact on long-term survival among GBM patients, interpreted as a potential predictive factor for better prognosis. (C) 2010 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

Cross-cultural adaptation and validation of a Brazilian Portuguese version of the chronic pain grade

To verify the reliability and validity of a Brazilian Portuguese version of the chronic pain grade (CPG-Br). Cultural adaptation was made in accordance with established guidelines, with modifications aiming at improving this process. Adaptations were made based on interviews with 45 chronic pain patients from So Paulo city. Validation was studied by concurrent application of the short-form-36 health survey (SF-36) and other questionnaires to 283 participants with chronic pain from the general population. Temporal stability was verified by a second application to 131 individuals. Factor analysis resulted in a two-factor solution with factors named characteristic pain intensity and activity limitation due to pain. Alpha coefficients of 0.78 and 0.70 and intraclass correlation coefficients of 0.76 and 0.72 for each factor indicated good internal consistency and temporal stability. Significant correlations between CPG-Br and SF-36, Roland-Morris disability questionnaire and neck disability index scores were noted. A consistent linear trend was also observed between pain grades and SF-36 scores. Frequency of use of pain medications and of pain-related medical visits increased with pain grade. This Brazilian Portuguese version of the chronic pain grade, tested on a sample of the Brazilian population, demonstrated good reliability and validity.

Acromegaly: correlation between expression of somatostatin receptor subtypes and response to octreotide-lar treatment

About one-third of acromegalics are resistant to the clinically available somatostatin analogs (SA). The resistance is related to density reduction or different expression of somatostatin receptor subtypes (SSTR). This study analyzes SSTR`s expression in somatotrophinomas, comparing to SA response, hormonal levels, and tumor volume. We analyzed 39 somatotrophinomas; 49% were treated with SA. The most expressed SSTR was SSTR5, SSTR3, SSTR2, SSTR1, and SSTR4, respectively. SSTR1 and SSTR2 had higher expression in patients that had normalized GH and IGF-I. SSTR3 was more expressed in patients with tumor reduction. There was a positive correlation between the percentage of tumor reduction and SSTR1, SSTR2 and SSTR3 expression. Also, a positive correlation between SSTR2 mRNA expression and the immunohistochemical reactivity of SSTR2 was found. Our study confirmed the association between the SA response to GH and IGF-I and the SSTR2. Additionally, this finding was also demonstrated in relation to SSTR1.

Correlation of fungi and endotoxin with PM2.5 and meteorological parameters in atmosphere of Sao Paulo, Brazil

Particulate matter, especially PM2.5, is associated with increased morbidity and mortality from respiratory diseases. Studies that focus on the chemical composition of the material are frequent in the literature, but those that characterize the biological fraction are rare. The objectives of this study were to characterize samples collected in Sao Paulo, Brazil on the quantity of fungi and endotoxins associated with PM2.5, correlating with the mass of particulate matter, chemical composition and meteorological parameters. We did that by Principal Component Analysis (PCA) and multiple linear regressions. The results have shown that fungi and endotoxins represent significant portion of PM2.5, reaching average concentrations of 772.23 spores mu g(-1) of PM2.5 (SD: 400.37) and 5.52 EU mg(-1) of PM2.5 (SD: 4.51 EU mg(-1)), respectively. Hyaline basidiospores, Cladosporium and total spore counts were correlated to factor Ba/Ca/Fe/Zn/K/Si of PM2.5 (p < 0.05). Genera Pen/Asp were correlated to the total mass of PM2.5 (p < 0.05) and colorless ascospores were correlated to humidity (p < 0.05). Endotoxin was positively correlated with the atmospheric temperature (p < 0.05). This study has shown that bioaerosol is present in considerable amounts in PM2.5 in the atmosphere of Sao Paulo, Brazil. Some fungi were correlated with soil particle resuspension and mass of particulate matter. Therefore, the relative contribution of bioaerosol in PM2.5 should be considered in future studies aimed at evaluating the clinical impact of exposure to air pollution. (C) 2010 Elsevier Ltd. All rights reserved.

Circulating levels of brain-derived neurotrophic factor: correlation with mood, cognition and motor function

Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the CNS, where it plays several pivotal roles in synaptic plasticity and neuronal survival. As a consequence, BDNF has become a key target in the physiopathology of several neurological and psychiatric diseases. Recent studies have consistently reported altered levels of BDNF in the circulation (i.e., serum or plasma) of patients with major depression, bipolar disorder, Alzheimer`s disease, Huntington`s disease and Parkinson`s disease. Correlations between serum BDNF levels and affective, cognitive and motor symptoms have also been described. BDNF appears to be an unspecific biomarker of neuropsychiatric disorders characterized by neurodegenerative changes.

High-Resolution Genomic Mapping Reveals Consistent Amplification of the Fibroblast Growth Factor Receptor Substrate 2 Gene in Well-Differentiated and Dedifferentiated Liposarcoma

Well-differentiated liposarcoma (WDLS) is one of the most common malignant mesenchymal tumors and dedifferentiated liposarcoma (DDLS) is a malignant tumor consisting of both WDLS and a transformed nonlipogenic sarcomatous component. Cytogenetically, WDLS is characterized by the presence of ring or giant rod chromosomes containing several amplified genes, including MDM2, TSPAN31 CDK4, and others mainly derived from chromosome bands 12q13-15. However, the 12q13-15 amplicon is large and discontinuous. The focus of this study was to identify novel critical genes that are consistently amplified in primary (nonrecurrent) WDLS and with potential relevance for future targeted therapy. Using a high-resolution (5.0 kb) ""single nucleotide polymorphism""/copy number variation microarray to screen the whole genome in a series of primary WDLS, two consistently amplified areas were found on chromosome 12: one region containing the MDM2 and CPM genes, and another region containing the FRS2 gene. Based on these findings, we further validated FRS2 amplification in both WDLS and DDLS. Fluorescence in situ hybridization confirmed FRS2 amplification in all WDLS and DDLS tested (n = 57). Real time PCR showed FRS2 mRNA transcriptional upregulation in WDLS (n = 19) and DDLS (n = 13) but not in lipoma (n = 5) and normal fat (n = 9). Immunoblotting revealed high expression levels of phospho-FRS2 at 1436 and slightly overexpression of total FRS2 protein in liposarcoma but not in normal fat or preadipocytes. Considering the critical role of FRS2 in mediating fibroblast growth factor receptor signaling, our findings indicate that FRS2 signaling should be further investigated as a potential therapeutic target for liposarcoma. (C) 2011 Wiley-Liss, Inc.

Transvaginal US after Bowel Preparation for Deeply Infiltrating Endometriosis: Protocol, Imaging Appearances, and Laparoscopic Correlation

Deeply infiltrating endometriosis (DIE) is a common gynecologic disease that is characterized by a difficult and delayed diagnosis. Radiologic mapping of the DIE lesion sites is crucial for case management, patient counseling, and surgical planning. Transvaginal ultrasonography (US) is the initial imaging modality for investigating DIE and has been the focus of several recent studies. DIE typically manifests at imaging as hypoechogenic nodules throughout the affected sites and thickening of the intestinal wall, with some lesions showing a mixed pattern due to cystic areas. Transvaginal US performed after bowel preparation improves the ability to diagnose intestinal lesions and provides invaluable details, including which layers of the intestine are affected and the distance between the lesion and the anal border. It is vital that radiologists be familiar with the technical aspects of this modality and with the US manifestations of DIE lesions. Transvaginal US performed after bowel preparation should be the first-line imaging modality for the evaluation of women with suspected endometriosis. (C) RSNA, 2010 . radiographics.rsna.org

Decreased recent thymus emigrant number in rheumatoid factor-negative polyarticular juvenile idiopathic arthritis

Objectives To determine TCR excision circle (TREC) levels, a marker of recent thymic emigrants, in the peripheral lymphocyte pool of rheumatoid factor-negative (RF circle divide) polyarticular juvenile idiopathic arthritis (JIA) children. Materials and methods We studied TREC levels in peripheral blood mononuclear cells (PBMC) in 30 RF circle divide polyarticular JIA children with active disease and in 30 age- and gender-matched healthy controls. Signal-joint TREC concentration was determined by real-time quantitative-PCR as the number of TREC copies/mu g PBMC DNA gauged by a standard curve with known number of TREC-containing plasmids. Results TREC levels in PBMC were significantly lower in JIA (4.90 +/- 3.86 x 10(4) TRECs/mu g DNA) as compared to controls (10.45 +/- 8.45 x 10(4) TRECs/mu g DNA, p=0.001). There was an inverse correlation between age and TREC levels in healthy children (r=-0.438, p=0.016) but not in JIA. No clinical association was observed between TREC levels and disease activity and use of oral steroids and methotrexate. Conclusions The finding of decreased PBMC TREC levels in RF circle divide polyarticular JIA children is consistent with a low proportion of recent thymus emigrants. This may interfere with the equilibrium between populations of polyclonal and naive T cells versus oligoclonal memory auto-reactive T cells and, therefore, may hinder the maintenance of immune tolerance in this disease.

Contrast-enhanced magnetic resonance imaging identifies focal regions of intramyocardial fibrosis, in patients with severe aortic valve disease: Correlation with quantitative histopathology

Background Chronic aortic valve disease (AVD) is characterized by progressive accumulation of interstitial myocardial fibrosis (MF). However, assessment of MF accumulation has only been possible through histologic analyses of endomyocardial biopsies. We sought to evaluate contrast-enhanced magnetic resonance imaging (ce-MRI) as a noninvasive method to identify the presence of increased MF in patients with severe AVD. Methods Seventy patients scheduled to undergo aortic valve replacement surgery were examined by cine and ce-MRI in a 1.5-T scanner. Cine images were used for the assessment of left ventricular (LV) volumes, mass, and function. Delayed-enhancement images were used to characterize the regions of MF. In addition, histologic analyses of myocardial samples obtained during aortic valve replacement surgery were used for direct quantification of interstitial MF. Ten additional subjects who died of noncardiac causes served as controls for the quantitative histologic analyses. Results Interstitial MF determined by histopathologic analysis was higher in patients with AVID than in controls (2.7% +/- 2.0% vs 0.6% +/- 0.2%, P =.001). When compared with histopathologic results, ce-MRI demonstrated a sensitivity of 74%, a specificity of 81%, and an accuracy of 76% to identify AVD patients with increased interstitial MF There was a significant inverse correlation between interstitial MF and LV ejection fraction (r = -0.67, P <.0001). Accordingly, patients with identifiable focal regions of MF by ce-MRI exhibited worse LV systolic function than those without MF (45% +/- 14% vs 65% +/- 14%, P <.0001). Conclusions Contrast-enhanced MRI allows for the noninvasive detection of focal regions of MF in patients with severe AVD. Moreover, patients with identifiable MF by ce-MRI exhibited worse LV functional parameters. (Am Heart J 2009; 157:361-8.)

No correlation and low agreement of imaging and inflammatory atherosclerosis` markers in familial hypercholesterolemia

Our purpose was to study the determinants of coronary and carotid subclinical atherosclerosis, aortic stiffness and their relation with inflammatory biomarkers in familial hypercholesterolemia (FH) subjects. Furthermore, we evaluated the agreement degree of imaging and inflammatory markers` severity used for coronary heart disease (CHD) prediction. Coronary calcium scores (CCS), carotid intima media thickness (IMT), carotid-femoral pulse wave velocity (PWV), C reactive protein (CRP) and white blood cells count (WBC) were determined in 89 FH patients (39 +/- 14 years, mean LDL-C=279 mg/dl) and in 31 normal subjects (NL). The following values were considered as imaging and biomarkers` severity: CCS > 75th% for age and sex, IMT > 900 mu m, PWV > 12 m/s, and CRP > 3 mg/l. Coronary artery calcification (CAC) prevalence and severity, IMT, PWV and WBC values were higher in FH than in NL (all parameters, p < 0.05). After multivariate analysis, the following variables were considered independent determinants of (1) IMT: systolic blood pressure, 10-year CHD risk by Framingham risk scores (FRS) and apolipoprotein B (r(2)=0.33); (2) PWV: age (r(2)=0.35); (3) CAC as a continuous variable: male gender and LDL-cholesterol year score (LYS) (r(2)=0.32); (4) presence of CAC as dichotomous variable: FRS (p=0.0027) and LYS (p=0.0228). With the exception of a moderate agreement degree between IMT and PWV severity (kappa=0.5) all other markers had only a slight agreement level (kappa < 0.1). In conclusion, clinical parameters poorly explained IMT, CAC and PWV variability in FH subjects. Furthermore, imaging markers and inflammatory biomarkers presented a poor agreement degree of their severity for CHD prediction. (C) 2007 Elsevier Ireland Ltd. All rights reserved.

Impaired interhemispheric interactions in patients with major depression

Previous studies have shown that patients with major depression have an interhemispheric imbalance between right and left prefrontal and motor cortex. We aimed to investigate the interhemispheric interactions in patients with major depression using repetitive transcranial magnetic stimulation (rTMS). Thirteen patients with major depression and 14 age-matched healthy subjects participated in this study. Corticospinal excitability before and after 1 Hz rTMS (applied to the left primary motor cortex) was assessed in the left and right motor cortex and these results were compared with those in healthy subjects. There was a significant difference in the interhemispheric effects between patients with depression and healthy subjects. In healthy subjects, 1 Hz rTMS significantly decreased corticospinal excitability in the stimulated, left hemisphere and increased it in the contralateral, right hemisphere. In depressed subjects, 1 Hz rTMS also decreased corticospinal excitability in the left hemisphere; however, it induced no significant changes in corticospinal excitability in the contralateral, right hemisphere. In addition, there was a significant correlation between the degree of interhemispheric modulation and the severity of the depression as indexed by the Beck Depression Inventory scores. Our findings showing a decreased interhemispheric modulation in patients with major depression are consistent with the notion that mood disorders are associated with slow interhemispheric switching mechanisms.