934 resultados para paired comparisons


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Alcoholism is highly prevalent among bipolar disorder (BD) patients, and its presence is associated with a worse outcome and refractoriness to treatment of the mood disorder. The neurobiological underpinnings that characterize this comorbidity are unknown. We sought to investigate the neurochemical profile of the dorsolateral prefrontal cortex (DLPFC) of BD patients with comorbid alcoholism. A short-TE, single-voxel (1)H spectroscopy acquisition at 1.5T from the left DLFPC of 22 alcoholic BD patients, 26 non-alcoholic BD patients and 54 healthy comparison subjects (HC) were obtained. Absolute levels of N-acetyl aspartate, phosphocreatine plus creatine, choline-containing compounds, myo-inositol, glutamate plus glutamine (Glu + Gln) and glutamate were obtained using the water signal as an internal reference. Analysis of co-variance was used to compare metabolite levels among the three groups. In the primary comparison, non-alcoholic BD patients had higher glutamate concentrations compared to alcoholic BD patients. In secondary comparisons integrating interactions between gender and alcoholism, non-alcoholic BD patients presented significantly higher glutamate plus glutamine (Glu + Gln) than alcoholic BD patients and HC. These results appeared to be driven by differences in male subjects. Alcoholic BD patients with additional drug use disorders presented significantly lower myo-inositol than BD patients with alcoholism alone. The co-occurrence of BD and alcoholism may be characterized by neurochemical abnormalities related to the glutamatergic system and to the inositol second messenger system and/or in glial pathology. These abnormalities may be the neurochemical correlate of an increased risk to develop alcoholism in BD, or of a persistently worse clinical and functional status in BD patients in remission from alcoholism, supporting the clinical recommendation that efforts should be made to prevent or early diagnose and treat alcoholism in BD patients. (C) 2009 Elsevier Ltd. All rights reserved.

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Neurobiological models support an involvement of white matter tracts in the pathophysiology of obsessive-compulsive disorder (OCD), but there has been little systematic evaluation of white matter volumes in OCD using magnetic resonance imaging (MRI). We investigated potential differences in the volume of the cingulum bundle (CB) and anterior limb of internal capsule (ALIC) in OCD patients (n = 19) relative to asymptomatic control subjects (n = 15). White matter volumes were assessed using a 1.5T MRI scanner. Between-group comparisons were carried out after spatial normalization and image segmentation using optimized voxel-based morphometry. Correlations between regional white matter volumes in OCD subjects and symptom severity ratings were also investigated. We found significant global white matter reductions in OCD patients compared to control subjects. The voxel-based search for regional abnormalities (with covariance for total white matter volumes) showed no specific white matter volume deficits in brain portions predicted a priori to be affected in OCD (CB and ALIC). However, large clusters of significant positive correlation with OCD severity scores were found bilaterally on the ALIC. These findings provide evidence of OCD-related ALIC abnormalities and suggest a connectivity dysfunction within frontal-striatal-thalamic-cortical circuits. Further studies are warranted to better define the role of such white matter alterations in the pathophysiology of OCD, and may provide clues for a more effectively targeting of neurosurgical treatments for OCD. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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Objective: The purpose of this study was to investigate regional structural abnormalities in the brains of five patients with refractory obsessive-compulsive disorder (OCD) submitted to gamma ventral capsulotomy. Methods: We acquired morphometric magnetic resonance imaging (MRI) data before and after 1 year of radiosurgery using a 1.5-T MRI scanner. Images were spatially normalized and segmented using optimized voxel-based morphometry (VBM) methods. Voxelwise statistical comparisons between pre- and post-surgery MRI scans were performed using a general linear model. Findings in regions predicted a priori to show volumetric changes (orbitofrontal cortex, anterior cingulate gyrus, basal ganglia and thalamus) were reported as significant if surpassing a statistical threshold of p<0.001 (uncorrected for multiple comparisons). Results: We detected a significant regional postoperative increase in gray matter volume in the right inferior frontal gyri (Brodmann area 47, BA47) when comparing all patients pre and postoperatively. Conclusions: Our results support the current theory of frontal-striatal-thalamic-cortical (FSTC) circuitry involvement in OCD pathogenesis. Gamma ventral capsulotomy is associated with neurobiological changes in the inferior orbitofrontal cortex in refractory OCD patients. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objectives: Magnetic resonance imaging (MRI) studies have reported an increased frequency of white matter hyperintensities (WMH) in association with late-onset (LO) depression, and this has supported the notion that vascular-related mechanisms may be implicated in the pathophysiology of LO mood disorders. Recent clinical studies have also suggested a link between LO bipolar disorder (LO-BD) and cerebrovascular risk factors, but this has been little investigated with neuroimaging techniques. In order to ascertain whether there could be a specific association between WMH and LO-BD, we directly compared WMH rates between LO-BD subjects (illness onset 60 years), early-onset BD subjects (EO-BD, illness onset < 60 years), and elderly healthy volunteers. Methods: T2-weighted MRI data were acquired in LO-BD subjects (n = 10, age = 73.60 +/- 4.09), EO-BD patients (n = 49, age = 67.78 +/- 4.44), and healthy subjects (n = 24, age = 69.00 +/- 7.22). WMH rates were assessed using the Scheltens scale. Results: There was a greater prevalence of WMH in LO-BD patients relative to the two other groups in the deep parietal region (p = 0.018) and basal ganglia (p < 0.045). When between-group comparisons of mean WMH scores were conducted taking account of age differences (ANCOVA), there were more severe scores in LO-BD patients relative to the two other groups in deep frontal and parietal regions, as well as in the putamen (p < 0.05). Conclusions: Our results provide empirical support to the proposed link between vascular risk factors and LO-BD. If extended in future studies with larger samples, these. findings may help to clarify the pathophysiological distinctions between bipolar disorder emerging at early and late stages of life.

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Background White-matter hyperintensities have been associated with both schizophrenia and mood disorders, particularly bipolar disorder, but results are inconsistent across studies. Aims To examine whether white-matter hyperintensities are a vulnerability marker for psychosis or are specifically associated with bipolar disorder. Method T-2-weighted magnetic resonance imaging data were acquired in 129 individuals with first-episode psychosis (either affective or non-affective psychoses) and 102 controls who were randomly selected from the same geographical areas. visual white-matter hyperintensity ratings were used for group and subgroup comparisons. Results There were no statistically significant between-group differences in white-matter hyperintensity frequency or severity scores. No significant correlations were found between white-matter hyperintensity scores and duration of illness, duration of untreated psychosis, or severity of psychotic, manic or depressive symptoms. Conclusions White-matter hyperintensities are not associated with vulnerability to psychosis in general, or specifically with affective psychoses. Further, first-episode psychosis investigations using more quantitative methods are warranted to confirm these findings. Declaration of interest None. Funding detailed in Acknowledgements.

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Although abnonnalities in brain structures involved in the neurobiology of fear and anxiety have been implicated in the pathophysiology of panic disorder (PD), relatively few studies have made use of voxel-based morphometry (VBM) magnetic resonance imaging (MRI) to determine structural brain abnormalities in PD. We have assessed gray matter volume in 19 PD patients and 20 healthy volunteers using VBM. Images were acquired using a 1.5 T MRI scanner, and were spatially normalized and segmented using optimized VBM. Statistical comparisons were performed using the general linear model. A relative increase in gay matter volume was found in the left insula of PD patients compared with controls. Additional structures showing differential increases were the left superior temporal gyrus, the midbrain, and the pons. A relative gray matter deficit was found in the right anterior cingulate cortex. The insula and anterior cingulate abnormalities may be relevant to the pathophysiology of PD, since these structures participate in the evaluation process that ascribes negative emotional meaning to potentially distressing cognitive and interoceptive sensory information. The abnormal brain stem structures may be involved in the generation of panic attacks. (C) 2007 Elsevier Ireland Ltd. All rights reserved.

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Objective: To investigate a possible association between a 3`UTR VNTR polymorphism of the dopamine transporter gene (SLC6A3) and ADHD in a Brazilian sample of adult patients. Method: Study Case-control with 102 ADHD adult outpatients (DSM-IV criteria) and 479 healthy controls. The primers` sequence used were: 3`UTR-Forward: 5`TGT GGT GAT GGG AAC GGC CTG AG 3` and 3`UTR-Reverse: 5`CTT CCT GGA GGT CAC GGC TCA AGG 3`. Alleles of the 3`UTR were coded according to their number of repeats: 6- repeat 320 bp (allele 6), 8- repeat 400 bp (allele 8), 9-repeat 480 bp (allele 9), 10- repeat 480 bp (allele 10), and 11- repeat 520 bp (allele 11). Results: There were no allelic (chi(2) = 2.67, 5df, p = .75) and genotypic (chi(2) = 7.20, 1df, p = .61) association between adult ADHD and VNTR 3`UTR polymorphism of SLC6A3. Conclusion: Our findings do not support SLC6A3 as marker genetic susceptibility factor in adult ADHD. More comprehensive polymorphism coverage within the SLC6A3 region should be conducted in larger samples, including comparisons in clinical subgroups, and in samples with different ethnic backgrounds. (J. of Att. Dis. 2011; 15(4) 305-309)

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Pseudomyxoma peritonei (PMP) is a clinical condition initially thought to be related to ovarian mucinous tumors; however, immunohistochemistry and molecular biology techniques have convincingly made the link to appendiceal mucinous neoplasms, resulting in changes in histologic and clinical approaches. The objective of this study was to compare the immunohistochemical profile of ovarian tumors associated with PMP and intestinal mucinous ovarian neoplasms without PMP. The study was retrospective and included 28 intestinal ovarian mucinous tumors selected from the files of the Division of Surgical Pathology of the University of Sao Paulo Medical School, from 1996 to 2005. Seven cases were associated with PMP of disseminated peritoneal adenomucinosis-type and all presented borderline histology. Immunohistochemical staining for mucin genes products (MUC1, MUC2, MUC5AC, and MUC6), CK7, CK20, CA19.9, and CA125 were performed in tissue microarrays. Of note, we detected differences in the expression of MUC2 and CK20 between cases with and without PMP. Comparisons of borderline histology with that of benign/malignant tumors also revealed differences in MUC2 and CK20. Our results confirm that there is a distinct profile of intestinal ovarian tumors associated with pseudomyxoma, particularly with respect to the expression of the gel-forming mucin MUC2. The profile of borderline tumors, even in cases without PMP, was distinct from that of other primary mucinous tumors of the intestinal type, suggesting that borderline histology may represent a secondary tumor or a less aggressive variant of PMP. An appendiceal origin seems the most probable for this group of neoplasias.

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Objective: Micro RNA (miRNA) is a class of small noncoding RNA that plays a major role in the regulation of gene expression, which has been related to cancer behavior. The possibility of analyzing miRNA from the archives of pathology laboratories is exciting, as it allows for large retrospective studies. Formalin is the most common fixative used in the surgical pathology routine, and its promotion of nucleic acid degradation is well known. Our aim is to compare miRNA profiles from formalin-fixed paraffin embedded (FFPE) tissues with fresh-frozen prostate cancer tissues. Methods: The expression of 14 miRNAs was determined by quantitative real time polymerase chain reaction (qRT-PCR) in 5 paired fresh-frozen and FFPE tissues, which were representative of prostate carcinoma. Results: There was a very good correlation of the miRNA expression of miR-let7c and miR-32 between the fresh-frozen and FFPE tissues, with Pearson`s correlation coefficients of 0.927 (P = 0.023) and 0.960 (P = 0.010), respectively. For the remaining miRNAs, the correlation was good with Spearman correlation coefficient of 0.638 (P < 0.001). Conclusion: Analysis of miRNAs from routinely processed and stored FFPE prostate tissue is feasible for some miRNAs using qRT-PCR. Further studies should be conducted to confirm the reliability of using stock tissues for miRNA expression determination. (C) 2011 Elsevier Inc. All rights reserved.

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Study design: Single-blind randomized, controlled clinical study. Objectives: To evaluate, using kinematic gait analysis, the results obtained from gait training on a treadmill with body weight support versus those obtained with conventional gait training and physiotherapy. Setting: Thirty patients with sequelae from traumatic incomplete spinal cord injuries at least 12 months earlier; patients were able to walk and were classified according to motor function as ASIA (American Spinal Injury Association) impairment scale C or D. Methods: Patients were divided randomly into two groups of 15 patients by the drawing of opaque envelopes: group A (weight support) and group B (conventional). After an initial assessment, both groups underwent 30 sessions of gait training. Sessions occurred twice a week, lasted for 30min each and continued for four months. All of the patients were evaluated by a single blinded examiner using movement analysis to measure angular and linear kinematic gait parameters. Six patients (three from group A and three from group B) were excluded because they attended fewer than 85% of the training sessions. Results: There were no statistically significant differences in intra-group comparisons among the spatial-temporal variables in group B. In group A, the following significant differences in the studied spatial-temporal variables were observed: increases in velocity, distance, cadence, step length, swing phase and gait cycle duration, in addition to a reduction in stance phase. There were also no significant differences in intra-group comparisons among the angular variables in group B. However, group A achieved significant improvements in maximum hip extension and plantar flexion during stance. Conclusion: Gait training with body weight support was more effective than conventional physiotherapy for improving the spatial-temporal and kinematic gait parameters among patients with incomplete spinal cord injuries. Spinal Cord (2011) 49, 1001-1007; doi:10.1038/sc.2011.37; published online 3 May 2011

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Obstetric complications play a role in the pathophysiology of schizophrenia. However, the biological consequences during neurodevelopment until adulthood are unknown. Microarrays have been used for expression profiling in four brain regions of a rat model of neonatal hypoxia as a common factor of obstetric complications. Animals were repeatedly exposed to chronic hypoxia from postnatal (PD) day 4 through day 8 and killed at the age of 150 days. Additional groups of rats were treated with clozapine from PD 120-150. Self-spotted chips containing 340 cDNAs related to the glutamate system (""glutamate chips"") were used. The data show differential (up and down) regulations of numerous genes in frontal (FR), temporal (TE) and parietal cortex (PAR), and in caudate putamen (CPU), but evidently many more genes are upregulated in frontal and temporal cortex, whereas in parietal cortex the majority of genes are downregulated. Because of their primary presynaptic occurrence, five differentially expressed genes (CPX1, NPY, NRXN1, SNAP-25, and STX1A) have been selected for comparisons with clozapine-treated animals by qRT-PCR. Complexin 1 is upregulated in FR and TE cortex but unchanged in PAR by hypoxic treatment. Clozapine downregulates it in FR but upregulates it in PAR cortex. Similarly, syntaxin 1A was upregulated in FR, but downregulated in TE and unchanged in PAR cortex, whereas clozapine downregulated it in FR but upregulated it in PAR cortex. Hence, hypoxia alters gene expression regionally specific, which is in agreement with reports on differentially expressed presynaptic genes in schizophrenia. Chronic clozapine treatment may contribute to normalize synaptic connectivity.

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The microtubule-associated protein Tau promotes the assembly and stability of microtubules in neuronal cells. Six Tau isoforms are expressed in adult human brain. All six isoforms become abnormally hyperphosphorylated and form neurofibrillary tangles in Alzheimer disease (AD) brains. In AD, reduced activity of phospholipase A(2) (PLA(2)), specifically of calcium-dependent cytosolic PLA(2) (cPLA(2)) and calcium-independent intracellular PLA(2) (iPLA(2)), was reported in the cerebral cortex and hippocampus, which positively correlated with the density of neurofibrillary tangles. We previously demonstrated that treatment of cultured neurons with a dual cPLA(2) and iPLA(2) inhibitor, methyl arachidonyl fluorophosphonate (MAFP), decreased total Tau levels and increased Tau phosphorylation at Ser(214) site. The aim of this study was to conduct a preliminary investigation into the effects of in vivo infusion of MAFP into rat brain on PLA(2) activity and total Tau levels in the postmortem frontal cortex and dorsal hippocampus. PLA(2) activity was measured by radioenzymatic assay and Tau levels were determined by Western blotting using the anti-Tau 6 isoforms antibody. MAFP significantly inhibited PLA(2) activity in the frontal cortex and hippocampus. The reactivity to the antibody revealed three Tau protein bands with apparent molecular weight of close to 40, 43 and 46 kDa in both brain areas. MAFP decreased the 46 kDa band intensity in the frontal cortex, and the 43 and 46 kDa band intensities in the hippocampus. The results indicate that in vivo PLA(2) inhibition in rat brain decreases the levels of total (nonphosphorylated plus phosphorylated) Tau protein and corroborate our previous in vitro findings.

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Early after stroke, there is loss of intracortical facilitation (ICF) and increase in short-interval intracortical inhibition (SICI) in the primary motor cortex (M1) contralateral to a cerebellar infarct. Our goal was to investigate intracortical M1 function in the chronic stage following cerebellar infarcts (> 4 months). We measured resting motor threshold (rMT), SICI, ICF, and ratios between motor-evoked potential amplitudes (MEP) and supramaximal M response amplitudes (MEP/M; %), after transcranial magnetic stimulation was applied to the M1 contralateral (M1(contralesional)) and ipsilateral (M1(ipsilesional)) to the cerebellar infarct in patients and to both M1s of healthy age-matched volunteers. SICI was decreased in M1(contralesional) compared to M1(ipsilesional) in the patient group in the absence of side-to-side differences in controls. There were no significant interhemispheric or between-group differences in rMT, ICF, or MEP/M (%). Our results document disinhibition of M1(contralesional) in the chronic phase after cerebellar stroke.

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Few studies have investigated in vivo changes of the cholinergic basal forebrain in Alzheimer`s disease (AD) and amnestic mild cognitive impairment (MCI), an at risk stage of AD. Even less is known about alterations of cortical projecting fiber tracts associated with basal forebrain atrophy. In this study, we determined regional atrophy within the basal forebrain in 21 patients with AD and 16 subjects with MCI compared to 20 healthy elderly subjects using deformation-based morphometry of MRI scans. We assessed effects of basal forebrain atrophy on fiber tracts derived from high-resolution diffusion tensor imaging (DTI) using tract-based spatial statistics. We localized significant effects relative to a map of cholinergic nuclei in MRI standard space as determined from a postmortem brain. Patients with AD and MCI subjects showed reduced volumes in basal forebrain areas corresponding to anterior medial and lateral, intermediate and posterior nuclei of the Nucleus basalis of Meynert (NbM) as well as in the diagonal band of Broca nuclei (P < 0.01). Effects in MCI subjects were spatially more restricted than in AD, but occurred at similar locations. The volume of the right antero-lateral NbM nucleus was correlated with intracortical projecting fiber tract integrity such as the corpus callosum, cingulate, and the superior longitudinal, inferior longitudinal, inferior fronto-occipital, and uncinate fasciculus (P < 0.05, corrected for multiple comparisons). Our findings suggest that a multimodal MRI-DTI approach is supportive to determine atrophy of cholinergic nuclei and its effect on intracortical projecting fiber tracts in AD. Hum Brain Mapp 32: 1349-1362, 2011. (C) 2010 Wiley-Liss, Inc.

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Background: Perioperative complications following robotic-assisted radical prostatectomy (RARP) have been previously reported in recent series. Few studies, however, have used standardized systems to classify surgical complications, and that inconsistency has hampered accurate comparisons between different series or surgical approaches. Objective: To assess trends in the incidence and to classify perioperative surgical complications following RARP in 2500 consecutive patients. Design, setting, and participants: We analyzed 2500 patients who underwent RARP for treatment of clinically localized prostate cancer (PCa) from August 2002 to February 2009. Data were prospectively collected in a customized database and retrospectively analyzed. Intervention: All patients underwent RARP performed by a single surgeon. Measurements: The data were collected prospectively in a customized database. Complications were classified using the Clavien grading system. To evaluate trends regarding complications and radiologic anastomotic leaks, we compared eight groups of 300 patients each, categorized according the surgeon`s experience (number of cases). Results and limitations: Our median operative time was 90 min (interquartile range [IQR]: 75-100 min). The median estimated blood loss was 100 ml (IQR: 100-150 ml). Our conversion rate was 0.08%, comprising two procedures converted to standard laparoscopy due to robot malfunction. One hundred and forty complications were observed in 127 patients (5.08%). The following percentages of patients presented graded complications: grade 1, 2.24%; grade 2, 1.8%; grade 3a, 0.08%; grade 3b, 0.48%; grade 4a, 0.40%. There were no cases of multiple organ dysfunction or death (grades 4b and 5). There were significant decreases in the overall complication rates (p = 0.0034) and in the number of anastomotic leaks (p < 0.001) as the surgeon`s experience increased. Conclusions: RARP is a safe option for treatment of clinically localized PCa, presenting low complication rates in experienced hands. Although the robotic system provides the surgeon with enhanced vision and dexterity, proficiency is only accomplished with consistent surgical volume; complication rates demonstrated a tendency to decrease as the surgeon`s experience increased. (C) 2010 European Association of Urology. Published by Elsevier B. V. All rights reserved.