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1.
J Virol ; 98(1): e0183023, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38088560

RESUMEN

Usutu virus (USUV) and West Nile virus (WNV) are closely related emerging arboviruses belonging to the Flavivirus genus and posing global public health concerns. Although human infection by these viruses is mainly asymptomatic, both have been associated with neurological disorders such as encephalitis and meningoencephalitis. Since USUV and WNV are transmitted through the bite of an infected mosquito, the skin represents the initial site of virus inoculation and provides the first line of host defense. Although some data on the early stages of WNV skin infection are available, very little is known about USUV. Herein, USUV-skin resident cell interactions were characterized. Using primary human keratinocytes and fibroblasts, an early replication of USUV during the first 24 hours was shown in both skin cells. In human skin explants, a high viral tropism for keratinocytes was observed. USUV infection of these models induced type I and III interferon responses associated with upregulated expression of various interferon-stimulated genes as well as pro-inflammatory cytokine and chemokine genes. Among the four USUV lineages studied, the Europe 2 strain replicated more efficiently in skin cells and induced a higher innate immune response. In vivo, USUV and WNV disseminated quickly from the inoculation site to distal cutaneous tissues. In addition, viral replication and persistence in skin cells were associated with an antiviral response. Taken together, these results provide a better understanding of the pathophysiology of the early steps of USUV infection and suggest that the skin constitutes a major amplifying organ for USUV and WNV infection.IMPORTANCEUsutu virus (USUV) and West Nile virus (WNV) are closely related emerging Flaviviruses transmitted through the bite of an infected mosquito. Since they are directly inoculated within the upper skin layers, the interactions between the virus and skin cells are critical in the pathophysiology of USUV and WNV infection. Here, during the early steps of infection, we showed that USUV can efficiently infect two human resident skin cell types at the inoculation site: the epidermal keratinocytes and the dermal fibroblasts, leading to the induction of an antiviral innate immune response. Moreover, following cutaneous inoculation, we demonstrated that both viruses can rapidly spread, replicate, and persist in all distal cutaneous tissues in mice, a phenomenon associated with a generalized skin inflammatory response. These results highlight the key amplifying and immunological role of the skin during USUV and WNV infection.


Asunto(s)
Infecciones por Flavivirus , Flavivirus , Tropismo Viral , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Animales , Humanos , Ratones , Antivirales , Culicidae , Infecciones por Flavivirus/virología , Interferones , Fiebre del Nilo Occidental/virología , Piel/inmunología , Piel/patología , Piel/virología , Técnicas In Vitro
2.
Neurobiol Dis ; 192: 106416, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38272141

RESUMEN

BACKGROUND: The dysregulation of the gut-brain axis in chronic inflammatory bowel diseases can cause neuro-psychological disturbances, but the underlying mechanisms are still not fully understood. The choroid plexus (CP) maintains brain homeostasis and nourishment through the secretion and clearance of cerebrospinal fluid. Recent research has demonstrated the existence of a CP vascular barrier in mice which is modulated during intestinal inflammation. This study investigates possible correlations between CP modifications and inflammatory activity in patients with Crohn's disease (CD). METHODS: In this prospective study, 17 patients with CD underwent concomitant abdominal and brain 3 T MRI. The volume and permeability of CP were compared with levels of C-reactive protein (CRP), fecal calprotectin (FC), sMARIA and SES-CD scores. RESULTS: The CP volume was negatively correlated with CRP levels (R = -0.643, p-value = 0.024) and FC (R = -0.571, p-value = 0.050). DCE metrics normalized by CP volume were positively correlated with CRP (K-trans: R = 0.587, p-value = 0.045; Vp: R = 0.706, p-value = 0.010; T1: R = 0.699, p-value = 0.011), and FC (Vp: R = 0.606, p-value = 0.037). CONCLUSIONS: Inflammatory activity in patients with CD is associated with changes in CP volume and permeability, thus supporting the hypothesis that intestinal inflammation could affect the brain through the modulation of CP vascular barrier also in humans.


Asunto(s)
Enfermedad de Crohn , Humanos , Animales , Ratones , Enfermedad de Crohn/diagnóstico por imagen , Enfermedad de Crohn/metabolismo , Plexo Coroideo/diagnóstico por imagen , Plexo Coroideo/metabolismo , Estudios Prospectivos , Eje Cerebro-Intestino , Biomarcadores/metabolismo , Proteína C-Reactiva/análisis , Proteína C-Reactiva/metabolismo , Complejo de Antígeno L1 de Leucocito/metabolismo , Índice de Severidad de la Enfermedad , Inflamación/diagnóstico por imagen , Permeabilidad
3.
Virol J ; 21(1): 163, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044231

RESUMEN

Usutu virus (USUV), an arbovirus from the Flaviviridae family, genus Flavivirus, has recently gained increasing attention because of its potential for emergence. After his discovery in South Africa, USUV spread to other African countries, then emerged in Europe where it was responsible for epizootics. The virus has recently been found in Asia. USUV infection in humans is considered to be most often asymptomatic or to cause mild clinical signs. However, a few cases of neurological complications such as encephalitis or meningo-encephalitis have been reported in both immunocompromised and immunocompetent patients. USUV natural life cycle involves Culex mosquitoes as its main vector, and multiple bird species as natural viral reservoirs or amplifying hosts, humans and horses can be incidental hosts. Phylogenetic studies carried out showed eight lineages, showing an increasing genetic diversity for USUV. This work describes the development and validation of a novel whole-genome amplicon-based sequencing approach to Usutu virus. This study was carried out on different strains from Senegal and Italy. The new approach showed good coverage using samples derived from several vertebrate hosts and may be valuable for Usutu virus genomic surveillance to better understand the dynamics of evolution and transmission of the virus.


Asunto(s)
Infecciones por Flavivirus , Flavivirus , Genoma Viral , Filogenia , Flavivirus/genética , Flavivirus/clasificación , Flavivirus/aislamiento & purificación , Animales , Infecciones por Flavivirus/virología , Infecciones por Flavivirus/veterinaria , Humanos , Senegal , Italia , Aves/virología , ARN Viral/genética , Variación Genética , Culex/virología , Secuenciación Completa del Genoma , Caballos/virología
4.
J Comput Assist Tomogr ; 48(2): 217-221, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37621087

RESUMEN

OBJECTIVE: The increasing number of coronary computed tomography angiography (CCTA) requests raised concerns about dose exposure. New dose reduction strategies based on artificial intelligence have been proposed to overcome limitations of iterative reconstruction (IR) algorithms. Our prospective study sought to explore the added value of deep-learning image reconstruction (DLIR) in comparison with a hybrid IR algorithm (adaptive statistical iterative reconstruction-veo [ASiR-V]) in CCTA, even in clinical challenging scenarios, as obesity, heavily calcified vessels and coronary stents. METHODS: We prospectively included 103 consecutive patients who underwent CCTA. Data sets were reconstructed with ASiR-V and DLIR. For each reconstruction signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) was calculated, and qualitative assessment was made with a four-point Likert scale by two independent and blinded radiologists with different expertise. RESULTS: Both SNR and CNR were significantly higher in DLIR (SNR-DLIR median value [interquartile range] of 13.89 [11.06-16.35] and SNR-ASiR-V 25.42 [22.46-32.22], P < 0.001; CNR-DLIR 16.84 [9.83-27.08] vs CNR-ASiR-V 10.09 [5.69-13.5], P < 0.001).Median qualitative score was 4 for DLIR images versus 3 for ASiR-V ( P < 0.001), with a good interreader reliability [intraclass correlation coefficient(2,1)e intraclass correlation coefficient(3,1) 0.60 for DLIR and 0.62 and 0.73 for ASiR-V].In the obese and in the "calcifications and stents" groups, DLIR showed significantly higher values of SNR (24.23 vs 11.11, P < 0.001 and 24.55 vs 14.09, P < 0.001, respectively) and CNR (16.08 vs 8.04, P = 0.008 and 17.31 vs 10.14, P = 0.003) and image quality. CONCLUSIONS: Deep-learning image reconstruction in CCTA allows better SNR, CNR, and qualitative assessment than ASiR-V, with an added value in the most challenging clinical scenarios.


Asunto(s)
Angiografía por Tomografía Computarizada , Aprendizaje Profundo , Humanos , Inteligencia Artificial , Estudios Prospectivos , Reproducibilidad de los Resultados , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Dosis de Radiación , Algoritmos , Procesamiento de Imagen Asistido por Computador
6.
Emerg Infect Dis ; 29(5): 1020-1024, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37081588

RESUMEN

During November 2021-May 2022, we identified 37 clinical cases of Streptococcus equi subspecies zooepidemicus infections in central Italy. Epidemiologic investigations and whole-genome sequencing showed unpasteurized fresh dairy products were the outbreak source. Early diagnosis by using sequencing technology prevented the spread of life-threatening S. equi subsp. zooepidemicus infections.


Asunto(s)
Productos Lácteos , Infecciones Estreptocócicas , Streptococcus equi , Humanos , Brotes de Enfermedades , Italia/epidemiología , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/diagnóstico , Streptococcus equi/genética
7.
PLoS Biol ; 18(4): e3000673, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32343693

RESUMEN

The mechanisms underlying virus emergence are rarely well understood, making the appearance of outbreaks largely unpredictable. Bluetongue virus serotype 8 (BTV-8), an arthropod-borne virus of ruminants, emerged in livestock in northern Europe in 2006, spreading to most European countries by 2009 and causing losses of billions of euros. Although the outbreak was successfully controlled through vaccination by early 2010, puzzlingly, a closely related BTV-8 strain re-emerged in France in 2015, triggering a second outbreak that is still ongoing. The origin of this virus and the mechanisms underlying its re-emergence are unknown. Here, we performed phylogenetic analyses of 164 whole BTV-8 genomes sampled throughout the two outbreaks. We demonstrate consistent clock-like virus evolution during both epizootics but found negligible evolutionary change between them. We estimate that the ancestor of the second outbreak dates from the height of the first outbreak in 2008. This implies that the virus had not been replicating for multiple years prior to its re-emergence in 2015. Given the absence of any known natural mechanism that could explain BTV-8 persistence over this long period without replication, we hypothesise that the second outbreak could have been initiated by accidental exposure of livestock to frozen material contaminated with virus from approximately 2008. Our work highlights new targets for pathogen surveillance programmes in livestock and illustrates the power of genomic epidemiology to identify pathways of infectious disease emergence.


Asunto(s)
Virus de la Lengua Azul/fisiología , Lengua Azul/virología , Genoma Viral , Animales , Evolución Biológica , Lengua Azul/epidemiología , Virus de la Lengua Azul/genética , Brotes de Enfermedades , Europa (Continente)/epidemiología , Francia , Ganado/virología , Mutación , Filogenia
8.
Eur Radiol ; 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38057593

RESUMEN

OBJECTIVE: To quantify the distribution of cauda equina nerve roots in supine and upright positions using manual measurements and radiomics features both in normal subjects and in lumbar spinal canal stenosis (LSCS) patients. METHODS: We retrospectively recruited patients who underwent weight-bearing MRI in supine and upright positions for back pain. 3D T2-weighted isotropic acquisition (3D-HYCE) sequences were used to develop a 3D convolutional neural network for identification and segmentation of lumbar vertebrae. Para-axial reformatted images perpendicular to the spinal canal and parallel to each vertebral endplate were automatically extracted. From each level, we computed the maximum antero-posterior (AP) and latero-lateral (LL) dispersion of nerve roots; further, radiomics features were extracted to quantify standardized metrics of nerve root distribution. RESULTS: We included 16 patients with LSCS and 20 normal subjects. In normal subjects, nerve root AP dispersion significantly increased from supine to upright position (p < 0.001, L2-L5 levels), and radiomics features showed an increase in non-uniformity. In LSCS subjects, in the upright position AP dispersion of nerve roots and entropy-related features increased caudally to the stenosis level (p < 0.001) and decreased cranially (p < 0.001). Moreover, entropy-related radiomics features negatively correlated with pre-operative Pain Numerical Rating Scale. Comparison between normal subjects and LSCS patients showed a difference in AP dispersion and increase of variance cranially to the stenosis level (p < 0.001) in the upright position. CONCLUSIONS: Nerve root distribution inside the dural sac changed between supine and upright positions, and radiomics features were able to quantify the differences between normal and LSCS subjects. CLINICAL RELEVANCE STATEMENT: The distribution of cauda equina nerve roots and the redundant nerve root sign significantly varies between supine and upright positions in normal subjects and spinal canal stenosis patients, respectively. Radiomics features quantify nerve root dispersion and correlates with pain severity. KEY POINTS: • Weight-bearing MRI depicts spatial distribution of the cauda equina in both supine and upright positions in normal subjects and spinal stenosis patients. • Radiomics features can quantify the effects of spinal stenosis on the dispersion of the cauda equina in the dural sac. • In the orthostatic position, dispersion of nerve roots is different in lumbar spinal stenosis patients compared to that in normal subjects; entropy-related features negatively correlated with pre-operative Pain Numerical Rating Scale.

9.
Radiol Med ; 128(6): 744-754, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37147473

RESUMEN

PURPOSE: Radiomics of vertebral bone structure is a promising technique for identification of osteoporosis. We aimed at assessing the accuracy of machine learning in identifying physiological changes related to subjects' sex and age through analysis of radiomics features from CT images of lumbar vertebrae, and define its generalizability across different scanners. MATERIALS AND METHODS: We annotated spherical volumes-of-interest (VOIs) in the center of the vertebral body for each lumbar vertebra in 233 subjects who had undergone lumbar CT for back pain on 3 different scanners, and we evaluated radiomics features from each VOI. Subjects with history of bone metabolism disorders, cancer, and vertebral fractures were excluded. We performed machine learning classification and regression models to identify subjects' sex and age respectively, and we computed a voting model which combined predictions. RESULTS: The model was trained on 173 subjects and tested on an internal validation dataset of 60. Radiomics was able to identify subjects' sex within single CT scanner (ROC AUC: up to 0.9714), with lower performance on the combined dataset of the 3 scanners (ROC AUC: 0.5545). Higher consistency among different scanners was found in identification of subjects' age (R2 0.568 on all scanners, MAD 7.232 years), with highest results on a single CT scanner (R2 0.667, MAD 3.296 years). CONCLUSION: Radiomics features are able to extract biometric data from lumbar trabecular bone, and determine bone modifications related to subjects' sex and age with great accuracy. However, acquisition from different CT scanners reduces the accuracy of the analysis.


Asunto(s)
Enfermedades Óseas Metabólicas , Tomografía Computarizada por Rayos X , Humanos , Niño , Tomografía Computarizada por Rayos X/métodos , Vértebras Lumbares/diagnóstico por imagen , Estudios Retrospectivos
10.
Anal Bioanal Chem ; 414(28): 8093-8105, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36136115

RESUMEN

The measure of hair cortisol concentration (HCC) is becoming an emerging approach to monitor mid-/long-term stress in animals, so it is more and more important to develop accurate and reliable methods. In the light of this, the aim of the present study was to compare mane HCCs of 47 horses with different managements, by means of an immunoassay (ELISA) and liquid chromatography coupled to hybrid high-resolution mass spectrometry (LC-HRMS/MS). After the washing step, the ground hair was extracted with methanol. The extract was evaporated and redissolved in two different aqueous solutions, depending on the detection technique. The methods were validated according to EMA guideline for bioanalytical method validation, in the range 2-50 pg mg-1 (ELISA) and 1-100 pg mg-1 (LC-HRMS/MS). Satisfactory quantitative performances were obtained for both of the approaches, but this latter demonstrated better precision. The detected concentrations in real samples were encompassing the range 1.3-8.8 pg mg-1 and 2.0-17.9 pg mg-1 by means of LC-HRMS/MS and ELISA, respectively. Overall, HCCs measured with ELISA technique were 1.6 times higher. The overestimation of immunoassay results might be caused by cross-reactivity phenomena of laboratory reagents and other structurally similar hormones present in the mane.


Asunto(s)
Cabello , Hidrocortisona , Caballos , Animales , Hidrocortisona/análisis , Cromatografía Liquida/métodos , Cabello/química , Espectrometría de Masas , Ensayo de Inmunoadsorción Enzimática , Inmunoensayo
11.
MAGMA ; 35(3): 467-483, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34665370

RESUMEN

OBJECTIVE: In this study we address the automatic segmentation of selected muscles of the thigh and leg through a supervised deep learning approach. MATERIAL AND METHODS: The application of quantitative imaging in neuromuscular diseases requires the availability of regions of interest (ROI) drawn on muscles to extract quantitative parameters. Up to now, manual drawing of ROIs has been considered the gold standard in clinical studies, with no clear and universally accepted standardized procedure for segmentation. Several automatic methods, based mainly on machine learning and deep learning algorithms, have recently been proposed to discriminate between skeletal muscle, bone, subcutaneous and intermuscular adipose tissue. We develop a supervised deep learning approach based on a unified framework for ROI segmentation. RESULTS: The proposed network generates segmentation maps with high accuracy, consisting in Dice Scores ranging from 0.89 to 0.95, with respect to "ground truth" manually segmented labelled images, also showing high average performance in both mild and severe cases of disease involvement (i.e. entity of fatty replacement). DISCUSSION: The presented results are promising and potentially translatable to different skeletal muscle groups and other MRI sequences with different contrast and resolution.


Asunto(s)
Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Pierna/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Músculo Esquelético/diagnóstico por imagen , Muslo/diagnóstico por imagen
12.
Hum Brain Mapp ; 42(13): 4348-4361, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34087040

RESUMEN

Deep gray matter nuclei are the synaptic relays, responsible to route signals between specific brain areas. Dentate nuclei (DNs) represent the main output channel of the cerebellum and yet are often unexplored especially in humans. We developed a multimodal MRI approach to identify DNs topography on the basis of their connectivity as well as their microstructural features. Based on results, we defined DN parcellations deputed to motor and to higher-order functions in humans in vivo. Whole-brain probabilistic tractography was performed on 25 healthy subjects from the Human Connectome Project to infer DN parcellations based on their connectivity with either the cerebral or the cerebellar cortex, in turn. A third DN atlas was created inputting microstructural diffusion-derived metrics in an unsupervised fuzzy c-means classification algorithm. All analyses were performed in native space, with probability atlas maps generated in standard space. Cerebellar lobule-specific connectivity identified one motor parcellation, accounting for about 30% of the DN volume, and two non-motor parcellations, one cognitive and one sensory, which occupied the remaining volume. The other two approaches provided overlapping results in terms of geometrical distribution with those identified with cerebellar lobule-specific connectivity, although with some differences in volumes. A gender effect was observed with respect to motor areas and higher-order function representations. This is the first study that indicates that more than half of the DN volumes is involved in non-motor functions and that connectivity-based and microstructure-based atlases provide complementary information. These results represent a step-ahead for the interpretation of pathological conditions involving cerebro-cerebellar circuits.


Asunto(s)
Corteza Cerebelosa/anatomía & histología , Núcleos Cerebelosos/anatomía & histología , Imagen de Difusión Tensora/métodos , Red Nerviosa/anatomía & histología , Adulto , Femenino , Humanos , Masculino
13.
J Neuroinflammation ; 18(1): 11, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407600

RESUMEN

BACKGROUND: Usutu virus (USUV) is an emerging neurotropic arthropod-borne virus recently involved in massive die offs of wild birds predominantly reported in Europe. Although primarily asymptomatic or presenting mild clinical signs, humans infected by USUV can develop neuroinvasive pathologies (including encephalitis and meningoencephalitis). Similar to other flaviviruses, such as West Nile virus, USUV is capable of reaching the central nervous system. However, the neuropathogenesis of USUV is still poorly understood, and the virulence of the specific USUV lineages is currently unknown. One of the major complexities of the study of USUV pathogenesis is the presence of a great diversity of lineages circulating at the same time and in the same location. METHODS: The aim of this work was to determine the neurovirulence of isolates from the six main lineages circulating in Europe using mouse model and several neuronal cell lines (neurons, microglia, pericytes, brain endothelial cells, astrocytes, and in vitro Blood-Brain Barrier model). RESULTS: Our results indicate that all strains are neurotropic but have different virulence profiles. The Europe 2 strain, previously described as being involved in several clinical cases, induced the shortest survival time and highest mortality in vivo and appeared to be more virulent and persistent in microglial, astrocytes, and brain endothelial cells, while also inducing an atypical cytopathic effect. Moreover, an amino acid substitution (D3425E) was specifically identified in the RNA-dependent RNA polymerase domain of the NS5 protein of this lineage. CONCLUSIONS: Altogether, these data show a broad neurotropism for USUV in the central nervous system with lineage-dependent virulence. Our results will help to better understand the biological and epidemiological diversity of USUV infection.


Asunto(s)
Flavivirus/fisiología , Flavivirus/patogenicidad , Inmunocompetencia/fisiología , Neuronas/fisiología , Neuronas/virología , Animales , Animales Recién Nacidos , Aves , Línea Celular Transformada , Chlorocebus aethiops , Flavivirus/aislamiento & purificación , Infecciones por Flavivirus/diagnóstico , Infecciones por Flavivirus/epidemiología , Humanos , Ratones , Células Vero , Virulencia/fisiología
14.
J Virol ; 95(1)2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33028716

RESUMEN

Genome segmentation is mainly thought to facilitate reassortment. Here, we show that segmentation can also allow differences in segment abundance in populations of bluetongue virus (BTV). BTV has a genome consisting in 10 segments, and its cycle primarily involves periodic alternation between ruminants and Culicoides biting midges. We have developed a reverse transcription-quantitative PCR (RT-qPCR) approach to quantify each segment in wild BTV populations sampled in both ruminants and midges during an epizootic. Segment frequencies deviated from equimolarity in all hosts. Interestingly, segment frequencies were reproducible and distinct between ruminants and biting midges. Beyond a putative regulatory role in virus expression, this phenomenon could lead to different evolution rates between segments.IMPORTANCE The variation in viral gene frequencies remains a largely unexplored aspect of within-host genetics. This phenomenon is often considered to be specific to multipartite viruses. Multipartite viruses have segmented genomes, but in contrast to segmented viruses, their segments are each encapsidated alone in a virion. A main hypothesis explaining the evolution of multipartism is that, compared to segmented viruses, it facilitates the regulation of segment abundancy, and the genes the segments carry, within a host. These differences in gene frequencies could allow for expression regulation. Here, we show that wild populations of a segmented virus, bluetongue virus (BTV), also present unequal segment frequencies. BTV cycles between ruminants and Culicoides biting midges. As expected from a role in expression regulation, segment frequencies tended to show specific values that differed between ruminants and midges. Our results expand previous knowledge on gene frequency variation and call for studies on its role and conservation beyond multipartite viruses.


Asunto(s)
Virus de la Lengua Azul/genética , Lengua Azul/virología , Genoma Viral/genética , Animales , Lengua Azul/transmisión , Ceratopogonidae/virología , Variaciones en el Número de Copia de ADN , Dosificación de Gen , Especificidad del Huésped , Insectos Vectores/virología , Ovinos
15.
J Magn Reson Imaging ; 51(1): 234-249, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31179595

RESUMEN

BACKGROUND: Fiber tracking with diffusion-weighted MRI has become an essential tool for estimating in vivo brain white matter architecture. Fiber tracking results are sensitive to the choice of processing method and tracking criteria. PURPOSE: To assess the variability for an algorithm in group studies reproducibility is of critical context. However, reproducibility does not assess the validity of the brain connections. Phantom studies provide concrete quantitative comparisons of methods relative to absolute ground truths, yet do no capture variabilities because of in vivo physiological factors. The ISMRM 2017 TraCED challenge was created to fulfill the gap. STUDY TYPE: A systematic review of algorithms and tract reproducibility studies. SUBJECTS: Single healthy volunteers. FIELD STRENGTH/SEQUENCE: 3.0T, two different scanners by the same manufacturer. The multishell acquisition included b-values of 1000, 2000, and 3000 s/mm2 with 20, 45, and 64 diffusion gradient directions per shell, respectively. ASSESSMENT: Nine international groups submitted 46 tractography algorithm entries each consisting 16 tracts per scan. The algorithms were assessed using intraclass correlation (ICC) and the Dice similarity measure. STATISTICAL TESTS: Containment analysis was performed to assess if the submitted algorithms had containment within tracts of larger volume submissions. This also serves the purpose to detect if spurious submissions had been made. RESULTS: The top five submissions had high ICC and Dice >0.88. Reproducibility was high within the top five submissions when assessed across sessions or across scanners: 0.87-0.97. Containment analysis shows that the top five submissions are contained within larger volume submissions. From the total of 16 tracts as an outcome relatively the number of tracts with high, moderate, and low reproducibility were 8, 4, and 4. DATA CONCLUSION: The different methods clearly result in fundamentally different tract structures at the more conservative specificity choices. Data and challenge infrastructure remain available for continued analysis and provide a platform for comparison. LEVEL OF EVIDENCE: 5 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2020;51:234-249.


Asunto(s)
Encéfalo/anatomía & histología , Imagen de Difusión Tensora/métodos , Imagen de Difusión por Resonancia Magnética , Humanos , Valores de Referencia , Reproducibilidad de los Resultados
16.
Cereb Cortex ; 29(3): 1351-1368, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30615116

RESUMEN

Action observation (AO) is crucial for motor planning, imitation learning, and social interaction, but it is not clear whether and how an action execution-observation network (AEON) processes the effort of others engaged in performing actions. In this functional magnetic resonance imaging (fMRI) study, we used a "squeeze ball" task involving different grip forces to investigate whether AEON activation showed similar patterns when executing the task or observing others performing it. Both in action execution, AE (subjects performed the visuomotor task) and action observation, AO (subjects watched a video of the task being performed by someone else), the fMRI signal was detected in cerebral and cerebellar regions. These responses showed various relationships with force mapping onto specific areas of the sensorimotor and cognitive systems. Conjunction analysis of AE and AO was repeated for the "0th" order and linear and nonlinear responses, and revealed multiple AEON nodes remapping the detection of actions, and also effort, of another person onto the observer's own cerebrocerebellar system. This result implies that the AEON exploits the cerebellum, which is known to process sensorimotor predictions and simulations, performing an internal assessment of forces and integrating information into high-level schemes, providing a crucial substrate for action imitation.


Asunto(s)
Encéfalo/fisiología , Cerebelo/fisiología , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología , Adulto , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/fisiología , Adulto Joven
17.
J Virol ; 92(19)2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30021901

RESUMEN

Arboviruses can cause a variety of clinical signs, including febrile illness, arthritis, encephalitis, and hemorrhagic fever. The recent Zika epidemic highlighted the possibility that arboviruses may also negatively affect the male reproductive tract. In this study, we focused on bluetongue virus (BTV), the causative agent of bluetongue and one of the major arboviruses of ruminants. We show that rams that recovered from bluetongue displayed signs of testicular degeneration and azoospermia up to 100 days after the initial infection. Importantly, testicular degeneration was induced in rams experimentally infected with either a high (BTV-1IT2006)- or a low (BTV-1IT2013)-virulence strain of BTV. Rams infected with the low-virulence BTV strain displayed testicular lesions in the absence of other major clinical signs. Testicular lesions in BTV-infected rams were due to viral replication in the endothelial cells of the peritubular areas of the testes, resulting in stimulation of a type I interferon response, reduction of testosterone biosynthesis by Leydig cells and destruction of Sertoli cells and the blood-testis barrier in more severe cases. Hence, BTV induces testicular degeneration and disruption of spermatogenesis by replicating solely in the endothelial cells of the peritubular areas unlike other gonadotropic viruses. This study shows that a naturally occurring arboviral disease can cause testicular degeneration and affect male fertility at least temporarily.IMPORTANCE During the recent Zika epidemic, it has become apparent that arboviruses could potentially cause reproductive health problems in male patients. Little is known regarding the effects that arboviruses have on the male reproductive tract. Here, we studied bluetongue virus (BTV), an arbovirus of ruminants, and its effects on the testes of rams. We show that BTV was able to induce testicular degeneration in naturally and experimentally infected rams. Testicular degeneration was caused by BTV replication in the endothelial cells of the peritubular area surrounding the seminiferous tubules (the functional unit of the testes) and was associated with a localized type I interferon response, destruction of the cells supporting the developing germinal cells (Sertoli cells), and reduction of testosterone synthesis. As a result of BTV infection, rams became azoospermic. This study highlights that problems in the male reproductive tract caused by arboviruses could be more common than previously thought.


Asunto(s)
Virus de la Lengua Azul/patogenicidad , Lengua Azul/complicaciones , Endotelio Vascular/patología , Infertilidad Masculina/etiología , Enfermedades de las Ovejas/etiología , Espermatogénesis , Testículo/patología , Animales , Lengua Azul/patología , Lengua Azul/virología , Endotelio Vascular/metabolismo , Endotelio Vascular/virología , Infertilidad Masculina/patología , Masculino , Ovinos , Enfermedades de las Ovejas/patología , Testículo/metabolismo , Testículo/virología , Testosterona/análisis , Virulencia , Replicación Viral
18.
J Med Virol ; 90(10): 1666-1668, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29797606

RESUMEN

A collection of 3069 human sera collected in the area of the municipality of Modena, Emilia Romagna, Italy, was retrospectively investigated for specific antibodies against Usutu (USUV) and West Nile viruses (WNV). All the samples resulting positive using a preliminary screening test were analyzed with the plaque reduction neutralization test. Overall, 24 sera were confirmed as positive for USUV (0.78%) and 13 for WNV (0.42%). The results suggest that in 2012, USUV was circulating more than WNV in North-eastern Italy.


Asunto(s)
Anticuerpos Antivirales/sangre , Flavivirus/inmunología , Virus del Nilo Occidental/inmunología , Anticuerpos Neutralizantes/sangre , Donantes de Sangre , Humanos , Italia/epidemiología , Pruebas de Neutralización , Estudios Retrospectivos , Estudios Seroepidemiológicos
19.
Euro Surveill ; 23(32)2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30107870

RESUMEN

In Italy, the 2018 West Nile virus transmission season started early with a high number of cases reported. One-Health surveillance, within the Italian West Nile national preparedness and response plan, detected viral circulation 9 days before symptom-onset of the first confirmed human case; triggering timely implementation of blood and transplant safety measures. This is an example of how functional coordination allows health authorities to use early warning triggers from surveillance systems to implement preventive measures.


Asunto(s)
Culicidae/virología , Vigilancia de la Población , Fiebre del Nilo Occidental/diagnóstico , Fiebre del Nilo Occidental/transmisión , Virus del Nilo Occidental/aislamiento & purificación , Animales , Brotes de Enfermedades , Humanos , Italia/epidemiología , Estaciones del Año , Fiebre del Nilo Occidental/epidemiología
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