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1.  Analysis of grey matter in thalamus and basal ganglia based on EEG α3/α2 frequency ratio reveals specific changes in subjects with mild cognitive impairment 
ASN NEURO  2012;4(7):e00103.
GM (grey matter) changes of thalamus and basal ganglia have been demonstrated to be involved in AD (Alzheimer's disease). Moreover, the increase of a specific EEG (electroencephalogram) marker, α3/α2, have been associated with AD-converters subjects with MCI (mild cognitive impairment). To study the association of prognostic EEG markers with specific GM changes of thalamus and basal ganglia in subjects with MCI to detect biomarkers (morpho-physiological) early predictive of AD and non-AD dementia. Seventy-four adult subjects with MCI underwent EEG recording and high-resolution 3D MRI (three-dimensional magnetic resonance imaging). The α3/α2 ratio was computed for each subject. Three groups were obtained according to increasing tertile values of α3/α2 ratio. GM density differences between groups were investigated using a VBM (voxel-based morphometry) technique. Subjects with higher α3/α2 ratios when compared with subjects with lower and middle α3/α2 ratios showed minor atrophy in the ventral stream of basal ganglia (head of caudate nuclei and accumbens nuclei bilaterally) and of the pulvinar nuclei in the thalamus; The integrated analysis of EEG and morpho-structural markers could be useful in the comprehension of anatomo-physiological underpinning of the MCI entity.
doi:10.1042/AN20120058
PMCID: PMC3522208  PMID: 23126239
Alzheimer's disease; basal ganglia; electroencephalogram (EEG); mild cognitive impairment; thalamus; voxel-based morphometry (VBM); AD, Alzheimer's disease; DARTEL, Diffeomorphic Anatomical Registration using Exponentiated Lie; EEG, electroencephalogram; fMRI, functional magnetic resonance imaging; GM, grey matter; IAF, individual α frequency; MCI, mild cognitive impairment; MMSE, Mini-Mental State Examination; PET, positron-emission tomography; TF, transition frequency; TIV, total intracranial volume; VBM, voxel-based morphometry
2.  Staging Alzheimer’s Disease Progression with Multimodality Neuroimaging 
Progress in neurobiology  2011;95(4):535-546.
Rapid developments in medical neuroimaging have made it possible to reconstruct the trajectory of Alzheimer’s disease (AD) as it spreads through the living brain. The current review focuses on the progressive signature of brain changes throughout the different stages of AD. We integrate recent findings on changes in cortical gray matter volume, white matter fiber tracts, neuropathological alterations, and brain metabolism assessed with molecular positron emission tomography (PET). Neurofibrillary tangles accumulate first in transentorhinal and cholinergic brain areas, and 4-D maps of cortical volume changes show early progressive temporo-parietal cortical thinning. Findings from diffusion tensor imaging (DTI) for assessment fiber tract integrity show cortical disconnection in corresponding brain networks. Importantly, the developmental trajectory of brain changes is not uniform and may be modulated by several factors such as onset of disease mechanisms, risk-associated and protective genes, converging comorbidity, and individual brain reserve. There is a general agreement between in vivo brain maps of cortical atrophy and amyloid pathology assessed through PET, reminiscent of post mortem histopathology studies that paved the way in the staging of AD. The association between in vivo and post mortem findings will clarify the temporal dynamics of pathophysiological alterations in the development of preclinical AD. This will be important in designing effective treatments that target specific underlying disease AD mechanisms.
doi:10.1016/j.pneurobio.2011.06.004
PMCID: PMC3223355  PMID: 21718750
Alzheimer’s disease; AD; mild cognitive impairment; MCI; pre-dementia; pre-clinical; pre-symptomatic; biological markers; neuroimaging; multimodal; neuropathology; neuroanatomy; computational; MRI; fMRI; DTI; VBM; DBM; tractography; drug development; clinical trials; CSF; staging; progression; diagnosis; classification; early detection; prediction; biological activity; ADNI; EADNI; regulatory authorities; FDA; EMEA
3.  Distribution and diversity of mycoplasma plasmids: lessons from cryptic genetic elements 
BMC Microbiology  2012;12:257.
Background
The evolution of mycoplasmas from a common ancestor with Firmicutes has been characterized not only by genome down-sizing but also by horizontal gene transfer between mycoplasma species sharing a common host. The mechanisms of these gene transfers remain unclear because our knowledge of the mycoplasma mobile genetic elements is limited. In particular, only a few plasmids have been described within the Mycoplasma genus.
Results
We have shown that several species of ruminant mycoplasmas carry plasmids that are members of a large family of elements and replicate via a rolling-circle mechanism. All plasmids were isolated from species that either belonged or were closely related to the Mycoplasma mycoides cluster; none was from the Mycoplasma bovis-Mycoplasma agalactiae group. Twenty one plasmids were completely sequenced, named and compared with each other and with the five mycoplasma plasmids previously reported. All plasmids share similar size and genetic organization, and present a mosaic structure. A peculiar case is that of the plasmid pMyBK1 from M. yeatsii; it is larger in size and is predicted to be mobilizable. Its origin of replication and replication protein were identified. In addition, pMyBK1 derivatives were shown to replicate in various species of the M. mycoides cluster, and therefore hold considerable promise for developing gene vectors. The phylogenetic analysis of these plasmids confirms the uniqueness of pMyBK1 and indicates that the other mycoplasma plasmids cluster together, apart from the related replicons found in phytoplasmas and in species of the clade Firmicutes.
Conclusions
Our results unraveled a totally new picture of mycoplasma plasmids. Although they probably play a limited role in the gene exchanges that participate in mycoplasma evolution, they are abundant in some species. Evidence for the occurrence of frequent genetic recombination strongly suggests they are transmitted between species sharing a common host or niche.
doi:10.1186/1471-2180-12-257
PMCID: PMC3541243  PMID: 23145790
Mycoplasma,Plasmid,Replication,Rep protein,Gene transfer,Evolution,Expression vector,Mycoplasma mycoides,Mycoplasma capricolum,Mycoplasma yeatsii
4.  The dynamics of Alzheimer's disease biomarkers in the Alzheimer's Disease Neuroimaging Initiative cohort 
Neurobiology of aging  2010;31(8):1263-1274.
The aim of this study was to investigate the dynamics of four of the most validated biomarkers for Alzheimer's disease (AD), cerebro-spinal fluid (CSF) Aβ 1–42, tau, hippocampal volume, and FDG-PET, in patients at different stage of AD. Two hundred twenty-nine cognitively healthy subjects, 154 mild cognitive impairment (MCI) patients converted to AD, and 193 (95 early and 98 late) AD patients were selected from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. For each biomarker, individual values were Z-transformed and plotted against ADAS-cog scores, and sigmoid and linear fits were compared. For most biomarkers the sigmoid model fitted data significantly better than the linear model. Aβ 1–42 time course followed a steep curve, stabilizing early in the disease course. CSF tau and hippocampal volume changed later showing similar monotonous trends, reflecting disease progression. Hippocampal loss trend was steeper and occurred earlier in time in APOE ε4 carriers than in non-carriers. FDG-PET started changing early in time and likely followed a linear decline. In conclusion, this study provides the first evidence in favor of the dynamic biomarker model which has recently been proposed.
doi:10.1016/j.neurobiolaging.2010.04.024
PMCID: PMC3467365  PMID: 20538373
Alzheimer's disease; Alzheimer's Disease Neuroimaging Initiative dataset; Biomarker dynamics; Cerebro-spinal fluid Aβ 42; Tau; Hippocampal volume; FDG-PET
5.  Evolutionary History of Contagious Bovine Pleuropneumonia Using Next Generation Sequencing of Mycoplasma mycoides Subsp. mycoides “Small Colony” 
PLoS ONE  2012;7(10):e46821.
Mycoplasma mycoides subsp. mycoides “Small Colony” (MmmSC) is responsible for contagious bovine pleuropneumonia (CBPP) in bovidae, a notifiable disease to the World Organization for Animal Health (OIE). Although its origin is not documented, the disease was known in Europe in 1773. It reached nearly world-wide distribution in the 19th century through the cattle trade and was eradicated from most continents by stamping-out policies. During the 20th century it persisted in Africa, and it reappeared sporadically in Southern Europe. Yet, classical epidemiology studies failed to explain the re-occurrence of the disease in Europe in the 1990s. The objectives of this study were to obtain a precise phylogeny of this pathogen, reconstruct its evolutionary history, estimate the date of its emergence, and determine the origin of the most recent European outbreaks. A large-scale genomic approach based on next-generation sequencing technologies was applied to construct a robust phylogeny of this extremely monomorphic pathogen by using 20 representative strains of various geographical origins. Sixty two polymorphic genes of the MmmSC core genome were selected, representing 83601 bp in total and resulting in 139 SNPs within the 20 strains. A robust phylogeny was obtained that identified a lineage specific to European strains; African strains were scattered in various branches. Bayesian analysis allowed dating the most recent common ancestor for MmmSC around 1700. The strains circulating in Sub-Saharan Africa today, however, were shown to descend from a strain that existed around 1810. MmmSC emerged recently, about 300 years ago, and was most probably exported from Europe to other continents, including Africa, during the 19th century. Its diversity is now greater in Africa, where CBPP is enzootic, than in Europe, where outbreaks occurred sporadically until 1999 and where CBPP may now be considered eradicated unless MmmSC remains undetected.
doi:10.1371/journal.pone.0046821
PMCID: PMC3468273  PMID: 23071648
6.  Functional Network Disruption in the Degenerative Dementias 
Lancet neurology  2011;10(9):829-843.
Despite considerable advances toward understanding the molecular pathophysiology of the neurodegenerative dementias, the mechanisms linking molecular changes to neuropathology and the latter to clinical symptoms remain largely obscure. Connectivity is a distinctive feature of the brain and the integrity of functional network dynamics is critical for normal functioning. A better understanding of network disruption in the neurodegenerative dementias may help bridge the gap between molecular changes, pathology and symptoms. Recent findings on functional network disruption as assessed with “resting-state” or intrinsic connectivity fMRI and EEG/MEG have shown distinct patterns of network disruption across the major neurodegenerative diseases. These network abnormalities are relatively specific to the clinical syndromes, and in Alzheimer's disease and frontotemporal dementia network disruption tracks the pattern of pathological changes. These findings may have a practical impact on diagnostic accuracy, allowing earlier detection of neurodegenerative diseases even at the pre-symptomatic stage, and tracking of disease progression.
doi:10.1016/S1474-4422(11)70158-2
PMCID: PMC3219874  PMID: 21778116
7.  Conservative versus surgical treatment of osteogenesis imperfecta: a retrospective analysis of 29 patients 
Summary
The aim of our study was to compare the surgical and conservative treatment of patients affected by fragility fractures and deformities of long bones in osteogenesis imperfecta (OI).
Our series consisted of 29 consecutive OI patients treated at our Institute. The series comprised 14 females and 15 males of different ages. The mean age at the time of the first treatment was 8 years (median 6 years; SD ± 15; range 1 to 75). The mean follow-up was 88 months. The Sillence classification was used to classify OI. Fifteen patients were classified as Type I; five as Type III and nine as Type IV.
A total number of 245 procedures were recorded. Of these, 147 were surgical (pinning; intramedullary nailing and plating) while 98 were conservative (cast, braces and bandages). Bisphosphonate use was a major variable in the study. Clinical charts and radiographic films were analyzed for complications (delayed union, nonunion, malunion, hardware loosening). We recorded 58 complications: 13 in Type I; 28 in Type III and 17 in Type IV OI. The rate of each complication was: 15/245 nonunions (6.1%), 14/245 delayed unions (5.7%), 14/245 malunions (5.7%) and 15/245 hardware loosenings (6.1%).
We found no statistically significant differences between surgical and conservative treatments. Type III OI, which is a very crippling form of the disease, was associated with radiographically poorer results than the other types. In our analysis, the two groups were unbalanced and only five patients were treated with bisphosphonates. Nevertheless, bisphosphonate use can be considered a good adjuvant to both the conservative and surgical treatment of OI in order to reduce the rate of complications.
PMCID: PMC3535993  PMID: 23289037
osteogenesis imperfecta; surgical treatment; conservative treatment; complications; bisphosphonates
8.  Quantitative EEG Markers in Mild Cognitive Impairment: Degenerative versus Vascular Brain Impairment 
We evaluated the relationship between brain rhythmicity and both the cerebrovascular damage (CVD) and amygdalohippocampal complex (AHC) atrophy, as revealed by scalp electroencephalography (EEG) in a cohort of subjects with mild cognitive impairment (MCI). All MCI subjects underwent EEG recording and magnetic resonance imaging. EEGs were recorded at rest. Relative power was separately computed for delta, theta, alpha1, alpha2, and alpha3 frequency bands. In the spectral band power the severity of CVD was associated with increased delta power and decreased alpha2 power. No association of vascular damage was observed with alpha3 power. Moreover, the theta/alpha1 ratio could be a reliable index for the estimation of the individual extent of CV damage. On the other side, the group with moderate hippocampal atrophy showed the highest increase of alpha2 and alpha3 power. Moreover, when the amygdalar and hippocampal volumes are separately considered, within amygdalohippocampal complex (AHC), the increase of theta/gamma ratio is best associated with amygdalar atrophy whereas alpha3/alpha2 ratio is best associated with hippocampal atrophy. CVD and AHC damages are associated with specific EEG markers. So far, these EEG markers could have a prospective value in differential diagnosis between vascular and degenerative MCI.
doi:10.1155/2012/917537
PMCID: PMC3412101  PMID: 22900229
9.  Steps to standardization and validation of hippocampal volumetry as a biomarker in clinical trials and diagnostic criteria for Alzheimer’s disease 
Alzheimer's & Dementia  2011;7(4):474-485.e4.
Background
The promise of Alzheimer’s disease (AD) biomarkers has led to their incorporation in new diagnostic criteria and in therapeutic trials; however, significant barriers exist to widespread use. Chief among these is the lack of internationally accepted standards for quantitative metrics. Hippocampal volumetry is the most widely studied quantitative magnetic resonance imaging (MRI) measure in AD and thus represents the most rational target for an initial effort at standardization.
Methods and Results
The authors of this position paper propose a path toward this goal. The steps include: 1) Establish and empower an oversight board to manage and assess the effort, 2) Adopt the standardized definition of anatomic hippocampal boundaries on MRI arising from the EADC-ADNI hippocampal harmonization effort as a Reference Standard, 3) Establish a scientifically appropriate, publicly available Reference Standard Dataset based on manual delineation of the hippocampus in an appropriate sample of subjects (ADNI), and 4) Define minimum technical and prognostic performance metrics for validation of new measurement techniques using the Reference Standard Dataset as a benchmark.
Conclusions
Although manual delineation of the hippocampus is the best available reference standard, practical application of hippocampal volumetry will require automated methods. Our intent is to establish a mechanism for credentialing automated software applications to achieve internationally recognized accuracy and prognostic performance standards that lead to the systematic evaluation and then widespread acceptance and use of hippocampal volumetry. The standardization and assay validation process outlined for hippocampal volumetry is envisioned as a template that could be applied to other imaging biomarkers.
doi:10.1016/j.jalz.2011.04.007
PMCID: PMC3396131  PMID: 21784356
Alzheimer’s disease; biomarkers; Magnetic resonance imaging; hippocampus; biomarker standards
10.  Alloprosthetic Composite is a Suitable Reconstruction After Periacetabular Tumor Resection 
Background
Resection of a tumor of the pelvis is most disabling when the acetabulum is excised and a durable reconstruction of the defect is hard to achieve. All available methods are associated with frequent complications. Few large series have been published, and fewer have focused entirely on complete resections of the acetabulum. The use of an allograft-prosthetic composite allows customization on the operating table. However, while such composites restore anatomy and function of the pelvis the use of pelvic allografts is controversial and the durability is unknown.
Questions/purposes
We therefore examined (1) the frequency of allograft and prosthetic failure, (2) positive and negative factors influencing the survival of the allograft prosthetic composite, and (3) function of patients with this reconstruction.
Patients and Methods
We retrospectively evaluated 35 patients who had resection of the entire acetabulum and reconstruction with an allograft-prosthetic composite. Function was scored by the Musculoskeletal Tumor Society system. Followup in 24 survivors averaged 120 months (range, 61–188 months).
Results
Greater than 75% of the allografts were still in place at last followup, and the original prosthetic reconstruction was still in place in 56%. Infection was an important negative factor for allograft survival. The average functional score was 72%, with better mean scores for patients who had reconstruction with a stemmed cup and an artificial ligament (average 89%).
Conclusions
An allograft-prosthetic composite provides a versatile substitution of the pelvis and hip, with functional scores approximately 75% of normal.
Level of Evidence
Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
doi:10.1007/s11999-011-1799-9
PMCID: PMC3069274  PMID: 21312077
11.  Local amygdala structural differences with 3T MRI in patients with Alzheimer disease 
Neurology  2011;76(8):727-733.
Objective:
Histologic studies show that the amygdala is affected by Alzheimer disease (AD) pathology, and its medial aspect is the most involved. We aimed to assess in vivo local structural differences in the amygdala of patients with AD using high-field MRI.
Methods:
A total of 19 patients with AD (mean age 76, SD 6 years, mean Mini-Mental State Examination score [MMSE] 13, SD 4) and 19 healthy elderly controls (age 74, SD 5, MMSE 29, SD 1) were enrolled. The radial atrophy mapping technique was used to reconstruct the 3-dimensional surface of the amygdala. Maps of surface tissue loss in patients with AD vs controls were computed and statistically tested with permutation tests thresholded at p < 0.05, to correct for multiple comparisons. A digital atlas of the amygdalar nuclei was used to infer which nuclei were involved.
Results:
Both amygdalar volumes were significantly smaller in patients with AD (right 1,508 mm3, SD 418; left 1,646, SD 419) than controls (right 2,129 mm3, SD 316; left 2,077, SD 376; p < 0.002). In the dorsomedial part, significant local tissue loss (20%–30%) was mapped in the medial and central nuclei. Ventrally, the lateral nucleus (La) and the basolateral ventral medial nucleus (BLVM) were also involved (20%–30% loss).
Conclusions:
We found in vivo local structural differences in the amygdala of patients with AD. The nuclei involved have known connections to the hippocampus (BLVM, La) and olfactory system (medial nucleus) and with cholinergic pathways (central nucleus). This pattern is consistent with the known pathophysiology of neural systems affected by AD.
doi:10.1212/WNL.0b013e31820d62d9
PMCID: PMC3053328  PMID: 21339500
12.  Specific EEG Changes Associated with Atrophy of Hippocampus in Subjects with Mild Cognitive Impairment and Alzheimer's Disease 
We evaluated the association between hippocampal atrophy and increase of the EEG markers alpha3/alpha2 relative power ratio in mild cognitive impairment (MCI) and Alzheimer's disease patients. Seventy-nine subjects with MCI and 11 patients with AD underwent EEG recording and MRI scan. The MCI group was subdivided in three subgroups according to growing hippocampal atrophy. The groups were characterized by alpha3/alpha2 relative power ratio. In AD patients group mapped hippocampal regions were computed and related with alpha3/alpha2 power ratio. Results show that the increase of alpha3/alpha2 power ratio is correlated with atrophy of hippocampus both in MCI and in Alzheimer's disease patients. This finding confirms the possible diagnostic role of EEG markers as diagnostic and prognostic factors in patient with prodromal and declared Alzheimer's disease.
doi:10.1155/2012/253153
PMCID: PMC3296269  PMID: 22506130
13.  Mapping the structural brain changes in Alzheimer’s disease: The independent contribution of two imaging modalities 
Journal of Alzheimer's Disease  2011;26(Suppl 3):263-274.
The macrostructural atrophy of Alzheimer’s disease (AD) has been fully described. Current literature reports that also microstructural alterations occur in AD since the early stages. However, whether the microstructural changes offer unique information independent from macrostructural atrophy is unclear. Aim of this study is to define the independent contribution of macrostructural atrophy and microstructural alterations on AD pathology.
The study involved 17 moderate to severe AD patients and 13 healthy controls. All participants underwent conventional and non conventional MRI (respectively, diffusion-weighted and T1-weighted MR scanning). We processed the images in order to obtain gray and white matter volumes to assess macrostructural atrophy, and fractional anisotropy and mean diffusivity to assess the microstructural damage. Analyses of covariance between patients and controls were performed to investigate microstructural tissue damage independent of macrostructural tissue loss, and viceversa, voxel by voxel.
We observed microstructural differences, independent of macrostructural atrophy, between patients and controls in temporal and retrosplenial regions, as well as in thalamus, corticopontine tracts, striatum and precentral gyrus. Volumetric differences, independent of microstructural alterations, were observed mainly in the entorhinal cortex, posterior cingulum, and splenium.
Measures of microstructural damage provide unique information not obtainable with volumetric mapping in regions known to be pivotal in AD as well as in others thought to be spared. This work expands the understanding of the topography of pathological changes in AD that can be captured with imaging techniques.
doi:10.3233/JAD-2011-0040
PMCID: PMC3267543  PMID: 21971466
Diffusion Tensor Imaging (DTI); Alzheimer’s disease (AD); Microstructure; Fractional Anisotropy (FA); Mean Diffusivity (MD)
14.  Injection of Demineralized Bone Matrix With Bone Marrow Concentrate Improves Healing in Unicameral Bone Cyst 
Background
Unicameral bone cysts are benign lesions that usually spontaneously regress with skeletal maturity; however, the high risk of pathologic fractures often justifies treatment that could reinforce a weakened bone cortex. Various treatments have been proposed but there is no consensus regarding the best procedure.
Questions/purposes
We compared the healing rates and failures of two methods of cure based on multiple injections of corticosteroid or a single injection of demineralized bone matrix (DBM) in association with bone marrow concentrate (BMC).
Methods
We retrospectively reviewed 184 patients who had one of the two treatments for unicameral bone cysts with cortical erosion. Clinical records were reviewed for treatment failures and radiographs for healing in all patients. The minimum followup was 12 months for the Steroids Group (mean, 48 months; range, 12–120 months) and 12 months for the DBM + BMC Group (mean, 20 months; range, 12–28 months).
Results
After one treatment we observed a lower healing rate of cysts treated with multiple injections of steroids compared with the healing after the first injection of DBM + BMC (21% versus 58%, respectively). At last followup, 38% healed with steroids and 71% with DBM + BMC. The rate of failure after one steroid injection was higher than after a single injection of BDM + BMC (63% versus 24%, respectively). We observed no difference in fracture rates after treatment between the two groups.
Conclusions
A single injection of DBM added with autologous bone marrow concentrate appears to provide a higher healing rate with a lower number of failures compared with a single injection of steroids.
Level of Evidence
Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
doi:10.1007/s11999-010-1430-5
PMCID: PMC2947677  PMID: 20568027
15.  Volumetric Differences in Mapped Hippocampal Regions Correlate with Increase of High Alpha Rhythm in Alzheimer's Disease 
Objective. The increase of high alpha relative to low alpha power has been recently demonstrated as a reliable EEG marker of hippocampal atrophy conversion of patients with mild cognitive impairment (MCI) in Alzheimer's disease (AD). In the present study we test the reliability of this EEG index in subjects with AD. Methods. Correlation between EEG markers and volumetric differences in mapped hippocampal regions was estimated in AD patients. Results. Results show that the increase of alpha3/alpha2 power ratio is correlated with atrophy of mapped hippocampal regions in Alzheimer's disease. Conclusions. The findings confirm the possible diagnostic role of EEG markers.
doi:10.4061/2011/208218
PMCID: PMC3132513  PMID: 21760984
16.  Electroencephalographic Rhythms in Alzheimer's Disease 
Physiological brain aging is characterized by synapses loss and neurodegeneration that slowly lead to an age-related decline of cognition. Neural/synaptic redundancy and plastic remodelling of brain networking, also due to mental and physical training, promotes maintenance of brain activity in healthy elderly subjects for everyday life and good social behaviour and intellectual capabilities. However, age is the major risk factor for most common neurodegenerative disorders that impact on cognition, like Alzheimer's disease (AD). Brain electromagnetic activity is a feature of neuronal network function in various brain regions. Modern neurophysiological techniques, such as electroencephalography (EEG) and event-related potentials (ERPs), are useful tools in the investigation of brain cognitive function in normal and pathological aging with an excellent time resolution. These techniques can index normal and abnormal brain aging analysis of corticocortical connectivity and neuronal synchronization of rhythmic oscillations at various frequencies. The present review suggests that discrimination between physiological and pathological brain aging clearly emerges at the group level, with suggested applications also at the level of single individual. The possibility of combining the use of EEG together with biological/neuropsychological markers and structural/functional imaging is promising for a low-cost, non-invasive, and widely available assessment of groups of individuals at-risk.
doi:10.4061/2011/927573
PMCID: PMC3100729  PMID: 21629714
17.  The clinical use of structural MRI in Alzheimer disease 
Nature reviews. Neurology  2010;6(2):67-77.
Structural imaging based on magnetic resonance is an integral part of the clinical assessment of patients with suspected Alzheimer dementia. Prospective data on the natural history of change in structural markers from preclinical to overt stages of Alzheimer disease are radically changing how the disease is conceptualized, and will influence its future diagnosis and treatment. Atrophy of medial temporal structures is now considered to be a valid diagnostic marker at the mild cognitive impairment stage. Structural imaging is also included in diagnostic criteria for the most prevalent non-Alzheimer dementias, reflecting its value in differential diagnosis. In addition, rates of whole-brain and hippocampal atrophy are sensitive markers of neurodegeneration, and are increasingly used as outcome measures in trials of potentially disease-modifying therapies. Large multicenter studies are currently investigating the value of other imaging and nonimaging markers as adjuncts to clinical assessment in diagnosis and monitoring of progression. The utility of structural imaging and other markers will be increased by standardization of acquisition and analysis methods, and by development of robust algorithms for automated assessment.
doi:10.1038/nrneurol.2009.215
PMCID: PMC2938772  PMID: 20139996
18.  Anatomical Substrate and Scalp EEG Markers are Correlated in Subjects with Cognitive Impairment and Alzheimer's Disease 
Dementia is a syndromic diagnosis, encompassing various stage of severity and different anatomo-physiological substrates. The hippocampus is one of the first and most affected brain regions affected by both Alzheimer's disease (AD) and mild cognitive impairment (MCI). Moreover, chronic cerebrovascular disease (CVD) is one of the major risk factor for developing dementia. Recent studies have demonstrated different relationship between the anatomical substrate and scalp electroencephalography (EEG) markers. Indeed, modifications of EEG rhythmicity is not proportional to the hippocampal atrophy, whereas changes in EEG activity are directly proportional to the load of subcortical CVD. The computation of the EEG spectral power and the analysis of the functional coupling of brain areas, through linear coherence, are two of the most known processing methods in EEG research. Two specific EEG markers, theta/gamma and alpha3/alpha2 frequency ratio have been reliable associated to the atrophy of amygdalo–hippocampal complex. Moreover, theta/gamma ratio has been related to MCI conversion in dementia and alpha3/alpha2 ratio has been specifically related to MCI conversion in AD. The functional coupling of brain areas is also modulated by hippocampal atrophy. In the MCI subjects, hippocampal atrophy is linked to an increase of interhemispheric coherence seen on frontal and temporal regions whereas subcortical CVD is linked to a decrease of coherence in fronto-parietal regions. In the present study the most significant results of recent studies on correlation between scalp EEG, cognitive decline, and anatomical substrate have been reviewed, with particular attention to the relationships between EEG changes and hippocampal atrophy. The following review is not intended to provide a comprehensive summary of the literature. Rather it identifies and discusses selected studies that are designed to find the specific correlation between scalp EEG markers and anatomo-pathological substrate. The principal aim is to propose a plausible neurophysiological theoretical model of the cognitive decline as mirrored by both structural and functional tools of research.
doi:10.3389/fpsyt.2010.00152
PMCID: PMC3059622  PMID: 21423459
EEG markers; Alzheimer's disease; mild cognitive impairment; alpha rhythm; theta rhythm
19.  Microstructural diffusion changes are independent of macrostructural volume loss in moderate to severe Alzheimer's disease 
Although it is established that Alzheimer's disease (AD) leads to cerebral macrostructural atrophy, microstructural diffusion changes have also been observed, but it is not yet known whether these changes offer unique information about the disease pathology. Thus, a multimodal imaging study was conducted to determine the independent contribution of each modality in moderate to severe AD.
17 patients with moderate-severe AD and 13 healthy volunteers underwent diffusion-weighted and T1-weighted MR scanning. Images were processed to obtain measures of macrostructural atrophy (GM and WM volumes) and microstructural damage (fractional anisotropy and mean diffusivity). Microstructural diffusion changes independent of macrostructural loss were investigated using an ANCOVA where macrostructural maps were used as voxel-wise covariates. The reverse ANCOVA model was also assessed, where macrostructural loss was the dependent variable and microstructural DTI maps were the imaging covariates.
Diffusion differences between patients and controls were observed after controlling for volumetric differences in medial temporal, retrosplenial regions, anterior commissure, corona radiata, internal capsule, thalamus, corticopontine tracts, cerebral peduncle, striatum and precentral gyrus. Independent volumetric differences were observed in the entorhinal cortex, inferior temporal lobe, posterior cingulate cortex, splenium and cerebellum.
While it is well known that AD is associated with pronounced volumetric change, this study suggests that measures of microstructure provide unique information not obtainable with volumetric mapping in regions known to be pivotal in AD and in those thought to be spared. As such this work provides great understanding of the topography of pathological changes in AD that can be captured with imaging.
doi:10.3233/JAD-2010-1295
PMCID: PMC2889147  PMID: 20157252
Diffusion Weighted Imaging (DWI); Alzheimer's disease (AD); Microstructure; Fractional Anisotropy (FA); Mean Diffusivity (MD)
20.  Autoimmune Hepatitis and Celiac Disease: Case Report Showing an Entero-Hepatic Link 
Case Reports in Gastroenterology  2010;4(3):469-475.
Celiac disease is an autoimmune disorder primarily targeting the small bowel, although extraintestinal extensions have been reported. The autoimmune processes can affect the liver with manifestations such as primary biliary cirrhosis and autoimmune hepatitis. We describe a 61-year-old woman with celiac disease and an increased levels of aminotransferases. The persistence of increased levels of aminotransferases after 1 year of gluten-free diet and the positivity for an anti-nuclear and anti-double-strand DNA antibodies led to a misdiagnosis of systemic lupus erythematosus-related hepatitis. Based on these findings the patient was placed on steroids, which after a few months were stopped because of the onset of diabetes mellitus. Soon after steroid withdrawal, the patient had a marked increase in aminotransferases and γ-globulins, and a liver biopsy revealed chronic active hepatitis. A course of three months of steroids and azathioprine normalized both biochemical and clinical parameters. Currently the patient is symptom-free and doing well. In conclusion, a hypertransaminasemia persisting after a gluten-free diet should be interpreted as a sign of coexisting autoimmune liver disease. Any autoantibody positivity (in this case to ANA and anti-dsDNA) should be carefully considered in order to avoid misdiagnosis delaying appropriate clinical management.
doi:10.1159/000321992
PMCID: PMC2988861  PMID: 21103207
Celiac disease; Autoimmune hepatitis; Hypertransaminasemia; γ-Globulins; Anti-dsDNA antibodies
21.  The Role of the Orthopaedic Specialist 
In recent years, cell therapy for bone regeneration has been found to have different indications in orthopaedic surgery, such as delayed fracture consolidation and the treatment of bone cysts and osteonecrosis.
The aims of regenerative medicine are to obtain healing in the shortest possible time, to use a mini-invasive approach and to reduce management costs.
Delayed consolidation can be defined radiographically as a fracture callus that is poorly evident or absent six months after osteosynthesis and its incidence ranges from 5 to 10% of long-bone fractures; to demonstrate the efficacy of regenerative therapy, we treated six patients aged between 19 and 53 years (mean 39 years) using a mini-invasive technique, preparing the fracture rim and applying, to the site, demineralised bone matrix (DBM) and mesenchymal stem cells (MSCs) obtained by harvesting bone marrow blood from the iliac crest. The sites treated were the tibia and the femur. Osteosynthesis was performed using an endomedullary nail in one case, an external fixing device in two, and a plate in three. Before our treatment, carried out between 4 and15 months after osteosynthesis (mean 8 months), all the patients were experiencing pain and none was completely loading the limb. The follow-up duration ranged from 3 to 18 months (mean 6 months) with checkups performed at 3, 6 and 12 months. Three months after the operation, five of the patients were completely loading the treated limb without pain and showed inter-fragment thickening on radiographic examination that allowed removal of the external fixing device in the two patients in whom it had been used, and at 12 months’ follow up showed complete clinical-radiographic healing.
The application of DBM and MSCs through mini-invasive surgery, performed a short time after osteosynthesis, reduced the healing time in patients with delayed consolidation and considerably reduced the costs of managing the condition itself.
Another field of application for regenerative medicine is the treatment of simple bone cysts, benign bone lesions that regress spontaneously when skeletal maturity is reached; nevertheless, their treatment is justified by the high risk of pathological fracture. To date, numerous techniques have been proposed to treat this disease, from curettage and bone grafting to cycles of cortisone injections. However, these techniques have limitations; either they are highly invasive or they involve a number of procedures carried out in close succession.
In 2007, we began a study comparing two groups of patients: the first treated with multiple cortisone injections and the second with a single injection of DBM associated with MSCs. The minimum follow up was 12 months. The mean follow up was 48 months (range 12–120 months) in the first group, and 19 months (range 12–29 months) in the second. The sites treated were the humerus (137 and 44 respectively) and femur (42 and 16 respectively).
At the end of the treatment, only 38% of the patients treated with cortisone could be defined healed, compared with 67% of those treated with DBM and MSCs. The treatment with a single injection of DBM and MSCs was thus found to be more effective in reducing healing times in patients with simple bone cysts.
Regenerative medicine is also indicated in hip osteonecrosis (ON). We treated 15 patients aged between 17 and 50 years (mean 32 years) with a mini-invasive technique involving decompression of the necrotic area and infiltration of DBM, MSCs and platelet-rich fibrin (PRF). Using the Ficat staging system, the ON was graded IIa–IIb in eight patients and III–IV in seven, with follow up lasting a mean of 6 months (range 3–14); checkups were scheduled at 3, 6 and 12 months. The mean Harris Hip Score showed an improvement: the score of the patients graded IIa–IIb rose from the 61 recorded preoperatively to 75 at 3 months, 82 at 6 months, and 98 at 12 months, whereas that of the patients graded III–IV rose from 57 preoperatively to 75 at 3 months, 76 at 6 months, and 86 at 12 months.
Even though the follow ups conducted are still short and the sample of patients small, the preliminary results of this study on the use of MSCs associated with DBM and PRF are promising.
All this suggests that the use of cells, in regenerative medicine, might be considered an effective and economic treatment possibility in orthopaedics.
PMCID: PMC3213792
22.  Mapping the effect of APOE ε4 on gray matter loss in Alzheimer's disease in vivo 
NeuroImage  2009;45(4):1090-1098.
Previous studies suggest that in Alzheimer's disease (AD) the Apolipoprotein E (APOE) ε4 allele is associated with greater vulnerability of medial temporal lobe structures. However, less is known about its effect on the whole cortical mantle. Here we aimed to identify APOE-related patterns of cortical atrophy in AD using an advanced computational anatomy technique. We studied 15 AD patients carriers (ε4+, age:72±10SD years, MMSE:20±3SD) and 14 non-carriers (ε4-, age:69±9, MMSE:20±5) of the ε4 allele and compared them to 29 age-and-sex matched controls (age:70±9, MMSE:28±1). Each subject underwent a clinical evaluation, a neuropsychological battery, and high-resolution MRI. UCLA's cortical pattern matching technique was used to identify regions of local cortical atrophy. ε4+ and ε4- patients showed similar performance on neuropsychological tests (p>.05, t-test). Diffuse cortical atrophy was detected for both ε4+ (p=.0001, permutation test) and ε4- patients (p=.0001, permutation test) relative to controls, and overall gray matter loss was about 15% in each patients group. Differences in gray matter loss between carriers and non-carriers mapped to the temporal cortex and right occipital pole (20% greater loss in carriers) and to the posterior cingulate, left orbitofrontal and dorsal fronto-parietal cortex (5-15% greater loss in non-carriers). APOE effect in AD was not significant (p>.74, ANOVA), but a significant APOE by region (temporal vs fronto-parietal cortex) interaction was detected (p=.002, ANOVA), in both early and late-onset patients (p<.05, ANOVA). We conclude that the ε4 allele modulates disease phenotype in AD, being associated with a pattern of differential temporal and fronto-parietal vulnerability.
doi:10.1016/j.neuroimage.2009.01.009
PMCID: PMC2739903  PMID: 19349226
Apolipoprotein E; Alzheimer disease; cortical atrophy; computational neuroanatomy; MRI
23.  Medial temporal atrophy but not memory deficit predicts progression to dementia in patients with mild cognitive impairment 
Background
The diagnosis of mild cognitive impairment (MCI) is clinically unhelpful, as many patients with MCI develop dementia but many do not.
Objective
To identify clinical instruments easily applicable in the clinical routine that might be useful to predict progression to dementia in patients with MCI assessed in the outpatient facility of a memory clinic.
Participants and methods
52 dementia‐free patients (mean (standard deviation) age 70 (6) years; 56% women) with MCI, and 65 healthy controls (age 69 (6) years; 54% women) underwent brain magnetic resonance scan with standardised visual assessment of medial temporal atrophy (MTA) and subcortical cerebrovascular lesions (SVLs). Follow‐up assessment occurred 15.4 (SD 3.4) months after baseline to detect incident dementia and improvement, defined as normal neuropsychological performance on follow‐up.
Results
Patients were classified into three groups according to the presence of memory disturbance only (MCI Mem), other neuropsychological deficits (MCI Oth) or both (MCI Mem+). MCI Mem and Mem+ showed MTA more frequently (31% and 47% v 5% and 14% of controls and MCI Oth, p<0.001). 11 patients developed dementia (annual rate 16.5%) and 7 improved on follow‐up. The only independent predictor of progression was MTA (odds ratio (OR) 7.1, 95% confidence interval (CI) 1.4 to 35.0), whereas predictors of improvement were the absence of memory impairment (OR 18.5, 95% CI 2.0 to 171.3) and normal MRI scan (OR 10.0, 95% CI 1.7 to 60.2).
Conclusion
Neuropsychological patterns identify groups of patients with MCI showing specific clinical features and risk of progression to dementia. MTA clinically rated with a visual scale is the most relevant predictor of progression and improvement.
doi:10.1136/jnnp.2005.082651
PMCID: PMC2077364  PMID: 16891386
24.  The pilot European Alzheimer’s Disease Neuroimaging Initiative (E-ADNI) of the European Alzheimer’s Disease Consortium 
Background
In North-America, the Alzheimer’s Disease Neuroimaging Initiative (ADNI) has established a platform to track the brain changes of Alzheimer’s disease. A pilot study has been carried out in Europe to test the feasibility of the adoption of the ADNI platform (pilot E-ADNI).
Methods
Seven academic sites of the European Alzheimer’s Disease Consortium (EADC) enrolled 19 patients with MCI, 22 with AD, and 18 older healthy persons using the ADNI clinical and neuropsychological battery. ADNI compliant MR scans, CSF and blood samples were shipped to central repositories. Medial temporal atrophy (MTA) and white matter hyperintensities (WMH) were assessed by a single rater using visual rating scales.
Results
Recruitment rate was 3.5 subjects per month per site. The cognitive, behavioural and neuropsychological features of the European subjects were very similar to their US counterparts. 3D T1-weighted MRI sequences were successfully performed on all subjects and CSF samples obtained from 77%, 68%, and 83% of AD, MCI, and controls. Mean MTA score showed a significant increase from controls (left, right: 0.4, 0.3) to MCI (0.9, 0.8) to AD (2.3, 2.0), while mean WMH score did not differ among the three diagnostic groups (between 0.7 and 0.9). The distribution of both MRI markers was comparable to matched US ADNI subjects.
Conclusions
Academic EADC centres can adopt the ADNI platform to enrol MCI and AD patients and older controls with global cognitive and structural imaging features remarkably similar to those of the US ADNI.
doi:10.1016/j.jalz.2008.04.009
PMCID: PMC2657833  PMID: 18631976
Alzheimer’s disease; mild cognitive impairment; imaging; CSF; ADNI; EADC
25.  Mild cognitive impairment (MCI) in medical practice: a critical review of the concept and new diagnostic procedure. Report of the MCI Working Group of the European Consortium on Alzheimer's Disease 
Mild cognitive impairment (MCI) was proposed as a nosological entity referring to elderly people with mild cognitive deficit but no dementia. MCI is a heterogeneous clinical entity with multiple sources of heterogeneity. The concept of MCI was reviewed and a diagnostic procedure with three different stages was proposed by the European Consortium on Alzheimer's Disease Working Group on MCI. Firstly, MCI should correspond to cognitive complaints coming from the patients or their families; the reporting of a relative decline in cognitive functioning during the past year by a patient or informant; cognitive disorders as evidenced by clinical evaluation; absence of major repercussions on daily life; and absence of dementia. These criteria, similar to those defined during an international workshop in Stockholm, make it possible to identify an MCI syndrome, which is the first stage of the diagnostic procedure. Secondly, subtypes of MCI had to be recognised. Finally, the aetiopathogenic subtype could be identified. Identifying patients at a high risk for progression to dementia and establishing more specific and adapted therapeutic strategies at an early stage, together with more structured overall management, is made possible by the diagnostic procedure proposed.
doi:10.1136/jnnp.2005.085332
PMCID: PMC2077456  PMID: 16549412

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