Biomedical subjects

Attilio Grop

Publications and source records attributed to Attilio Grop.

6 recordsLinked to original sources

PubMed2006

Positivity of cytomegalovirus antibodies predicts a better clinical and radiological outcome in multiple sclerosis patients.

OBJECTIVES: To establish the relationship between the presence and titer of virus-specific serum- and cerebrospinal fluid (CSF)-antibodies in multiple sclerosis (MS) patients and disease severity measured with different quantitative magnetic resonance imaging (MRI) techniques. METHODS: We investigated an association between clinical and MRI measures of disease activity and the presence and titer of IgG antibodies against seven common viruses (measles, rubella, herpes simplex virus type 1 and 2, varicella zoster virus, cytomegalovirus (CMV) and Epstein-Barr virus). One hundred and forty (90 female/50 male) patients with definite MS and 131 age and sex-matched controls participated in the study. Antibody positivity and titer were ascertained by the enzyme linked immunosorbent assay (ELISA) technique and clinical assessment was performed by evaluating the expanded disability status scale (EDSS) score and the lifetime relapse rate (LRR). T1- and T2-lesion loads (LL) and the brain parenchymal fraction (BPF) were calculated. RESULTS: Multiple analyses showed that there was an association between antibody positivity against CMV and higher titer and better clinical and MRI outcomes. The cluster analyses indicated that patients positive for antibodies against CMV had significantly older age at onset (uncorr p = 0.001 and corr p = 0.009), lower LRR (uncorr p = 0.003 and corr p = 0.03) and higher BPF (uncorr p = 0.004 and pcorr p = 0.04). CMV-positive patients who had higher antibody titer showed lower T2-LL (uncorr p = 0.003 and corr p = 0.03) and higher BPF (uncorr p = 0.006 and corr p = 0.05). DISCUSSION: Surprisingly, our results focused attention on the 'protective' role of a particular virus. CMV is probably capable of triggering some immunomodulating/immune evasion mechanisms which may decrease immune reactivity in MS patients. Further studies are needed to confirm and elucidate our study results on a larger sample of MS patients and in animal model studies.

Adolescent↗

PubMed2005

Reproducibility and accuracy of quantitative magnetic resonance imaging techniques of whole-brain atrophy measurement in multiple sclerosis.

BACKGROUND AND PURPOSE: Whole-brain atrophy is of growing interest as an outcome measure in multiple sclerosis (MS) clinical trials. The authors compared the reproducibility and accuracy of 3 quantitative techniques of measurement in patients with MS. METHODS: Thirty-four patients with relapsing-remitting MS (median Expanded Disability Status Scale disability score = 1.5) were studied. Brain parenchymal fraction (BPF) was quantified on spin-echo 2-dimensional T1-weighted axial 5-mm slice thickness sequences by semiautomated (Buffalo, Trieste) or automated (SIENAX) algorithms. RESULTS: Mean +/- SD BPFs were 0.830 +/- 0.04 with Buffalo, 0.824 +/- 0.04 with Trieste, and 0.826 +/- 0.04 with SIENAX methods (P = nonsignificant [NS]). Mean BPF scan-rescan coefficient of variation (COV) was 0.41% for Buffalo, 0.44% for Trieste, and 0.32% for SIENAX (P =NS).The semiautomated methods showed higher accuracy than the automated method in brain extraction (masking; P = .001). The errors of skull stripping included scalp, skull bone marrow, inferior parts of temporal lobes anterior to the brain stem, face structures, sagittal sinuses, eyes, and optic nerves. Buffalo (r = -0.37, P = .034) and Trieste (r = -.36, P = .039) BPFs showed stronger cor relation with disability than SIENAX (r = -0.16, P = .219). These differences were statistically significant (P = .0031 for Buffalo and P = .0037 for Trieste BPF). CONCLUSIONS: This study showed a high reproducibility of both semiautomated and automated methods for brain atrophy measurement. The semiautomated methods showed higher accuracy than the automated SIENAX method did in the evaluation of brain extraction, especially in infratentorial and cortical regions, where operator interaction during the masking processes was essential.

Adult↗

PubMed2004

Short-term brain atrophy changes in relapsing-remitting multiple sclerosis.

The objective of this study was to establish whether the time interval of 3 months is sufficient to detect whole-brain atrophy changes in patients with relapsing-remitting (RR) multiple sclerosis (MS). Another aim was to assess the value of monthly gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) and of different Gd-enhancement patterns as predictors of brain atrophy. Thirty patients with RRMS (mean disease duration 4.9 years, mean age 34.4 years and mean Expanded Disability Status Scale [EDSS] 1.4) were assessed at baseline and monthly for a period of 3 months with clinical and MRI examinations. Calculations of baseline and monthly absolute and percent changes of MRI measures have been obtained using two semiautomated (Buffalo and Trieste) and one automated (SPM99) segmentation method. Changes of brain parenchymal fraction (BPF) were investigated according to Gd-enhancement patterns. Mean absolute and percent changes of BPF did not significantly differ at any time point in the study for any of the three methods. There was slight but not significant decrease of BPF from baseline to month 3: -0.0004 (0.05%), p=0.093 for Trieste; -0.0006 (0.07%), p=0.078 for Buffalo; and -0.0006 (0.08%), p=0.081 for SPM99 method. In ring-enhancement positive patients, there was a significant difference between baseline and month 3 changes of BPF, EDSS, and number of relapses. Over the study period, we did not demonstrate differences between changes of BPF according to the presence of Gd enhancement. Longitudinally, multiple regression analysis demonstrated that the only clinical or MRI parameter that predicted BPF decrease was the mean absolute change of ring-enhancing lesion load (R=0.62, p=0.003). The noteworthy findings of this study are (1) the observation that a significant brain atrophy progression cannot be detected over a 3-month period in RRMS; (2) the demonstration that the ring-enhancement pattern may contribute to more severe brain tissue loss in the short term; and (3) the lack of relationship between the presence and duration of Gd-enhancement activity and brain volume changes in the short term.

Adult↗

PubMed2004

MMP-9 microsatellite polymorphism and multiple sclerosis.

A polymorphism (PM) in the microsatellite of the promoter region of matrix metalloproteinase 9 (MMP-9), modulating its expression, could play a role in susceptibility to multiple sclerosis (MS). MMP-9 PM was determined in 95 patients with MS (MS Group) and 95 age- and sex-matched controls (Control Group). Comparison of allelic frequencies showed that a higher number of CA repeats characterized the MS group (P<0.0001) and prevalence of carriers of > or =22 CA repeats was higher in the MS than in the Control Group (OR 3.4, 95% CI: 1.7-6.8, P<0.0001). An earlier age at disease onset was a characteristic of patients with >22 CA repeats (33+/-10 vs. 28+/-10, P=0.027). No differences were found in the main MRI parameters.

Adolescent↗

PubMed2004

Frontal parenchymal atrophy measures in multiple sclerosis.

The aim of this study was to establish whether, in a cross-sectional study, the normalized measures of whole and regional brain atrophy correlate better with tests assessing the cognitive function than the absolute brain atrophy measures. The neuropsychological performances and disability have been assessed in 39 patients with relapsing-remitting multiple sclerosis (MS). T1- and T2-lesion load (LL) of total brain and frontal lobes (FLs) were measured using a reproducible semiautomated technique. The whole brain volume and the regional brain parenchymal volume (RBPV) of FLs were obtained using a computerized interactive program, which incorporates semiautomated and automated segmentation processes. Normalized measures of brain atrophy, i.e., brain parenchymal fraction (BPF) and regional brain parenchymal fraction (RBPF) of FLs, were calculated. The scan-rescan, inter- and intrarater coefficient of variation (COV) and intraclass correlation coefficient (ICC) have been estimated. The RBPF of FLs showed an acceptable level of reproducibility which ranged from 1.7% for intrarater variability to 3.2% for scan-rescan variability. The mean ICC was 0.88 (CI 0.82-0.93). The RBPF of FLs demonstrated stronger magnitudes of correlation with neuropsychological functioning, disability and quantitative MRI lesion measures than RBPV. These differences were statistically significant: P<0.001 for Stroop Color Word Interference test, P<0.001 for Paced Auditory Serial Addition Test, P=0.04 for Standard Raven Progressive Matrices, P=0.049 for Expanded Disability Status Scale, P=0.01 for T2-LL of FLs and P<0.001 for T1-LL of FLs. BPF demonstrated significant correlations with tests assessing cognitive functions, whereas BPAV did not. The correlation analysis results were supported by the results of multiple regression analysis which showed that only the normalized brain atrophy measures were associated with tests exploring the cognitive functions. These data suggest that RBPF is a reproducible and sensitive method for measuring frontal parenchymal atrophy. The normalized measures of whole and regional brain parenchymal atrophy should be preferred to absolute measures in future studies that correlate neuropsychological performances and brain atrophy measures in patients with MS.

Adult↗

PubMed2003

Normalized regional brain atrophy measurements in multiple sclerosis.

There is still a controversy regarding the best regional brain atrophy measurements in multiple sclerosis (MS) studies. The aim of this study was to establish whether, in a cross-sectional study, the normalized measurements of regional brain atrophy correlate better with the MRI-defined regional brain lesions than the absolute measurements of regional brain atrophy. We assessed 45 patients with clinically definite relapsing-remitting (RR) MS (median disease duration 12 years), and measured T1-lesion load (LL) and T2-LL of frontal lobes and pons, using a reproducible semi-automated technique. The regional brain parenchymal volume (RBPV) of frontal lobes and pons was obtained by use of a computerized interactive program, which incorporates semi-automated and automated segmentation processes. A normalized measurement, the regional brain parenchymal fraction (RBPF), was calculated as the ratio of RBPV to the total volume of the parenchyma and the cerebrospinal fluid (CSF) in the frontal lobes and in the region of the pons. The total regional brain volume fraction (TRBVF) was obtained after we had corrected for the total volume of the parenchyma and the CSF in the frontal lobes and in the region of the pons for the total intracranial volume. The mean coefficient of variation (CV) for RBPF of the pons was 1% for intra-observer reproducibility and 1.4% for inter-observer reproducibility. Generally, the normalized measurements of regional brain atrophy correlated with regional brain volumes and disability better than did the absolute measurements. RBPF and TRBVF correlated with T2-LL of the pons (r=-0.37, P=0.011, and r= -0.40, P=0.0005 respectively) and with T1-LL of the pons (r=-0.27, P=0.046, and r=-0.31, P=0.04, respectively), whereas RBPV did not (r=-0.18, P = NS). T1-LL of the frontal lobes was related to RBPF (r=-0.32, P=0.033) and TRBVF (r=-0.29, P=0.05), but not to RBPV (R=-0.27, P= NS). There was only a trend of correlation between T2-LL of the frontal lobes and RBPF (r=-0.27, P=0.06) and TRBVF (r=-0.28, P=0.057), and no correlation with RBPV (r=-0.23, P= NS). The magnitude of correlation between the expanded disability status scale (EDSS) and pontine and frontal lobe RBPF and TRBVF was more than twice as high as the correlation between EDSS and RBPV of the same regions. These data suggest that normalized regional brain atrophy measurements are preferable to absolute regional measurements in cross-sectional studies.

Adult↗