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Advanced connectivity studies in toddlers with Autism Spectrum Disorder (ASD) are increasing and consistently reporting a disruption of brain connectivity. However, most of these studies compare ASD and typically developing subjects, thus providing little information on the specificity of the abnormalities detected in comparison with other developmental disorders (other-DD). We recruited subjects aged below 36 months who received a clinical diagnosis of Neurodevelopmental Disorder (32 ASD and 16 other-DD including intellectual disability and language disorder) according to DSM-IV TR. Structural and diffusion MRI were acquired to perform whole brain probabilistic and anatomically constrained tractography. Network connectivity matrices were built encoding the number of streamlines (DNUM) and the tract-averaged fractional anisotropy (DFA) values connecting each pair of cortical and subcortical regions. Network Based Statistics (NBS) was finally applied on the connectivity matrices to evaluate the network differences between the ASD and other-DD groups. The network differences resulted in an over-connectivity pattern (i.e., higher DNUM and DFA values) in the ASD group with a significance of P < 0.05. No contra-comparison results were found. The over-connectivity pattern in ASD occurred in networks primarily involving the fronto-temporal nodes, known to be crucial for social-skill development and basal ganglia, related to restricted and repetitive behaviours in ASD. To our knowledge, this is the first network-based diffusion study comparing toddlers with ASD and those with other-DD. Results indicate the detection of different connectivity patterns in ASD and other-DD at an age when clinical differential diagnosis is often challenging. Hum Brain Mapp 38:2333-2344, 2017. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A detailed analysis of a Mediterranean tropical-like cyclone (MTLC) that occurred in January 2014 has been conducted. After having identified the cyclone path and its general features, the GLOBO, BOLAM and MOLOCH numerical weather prediction (NWP) models, developed at the National Research Council - Institute of Atmospheric Sciences and Climate (CNR-ISAC) in Bologna, were used to simulate the phenomenon. Particular attention was paid to the Mediterranean phase of the system life cycle as well as to the Atlantic phase, since the cyclone showed a well-defined precursor up to 3 days before the formation of the mean sea-level pressure (MSLP) minimum over the Alboran Sea. The Mediterranean phase was studied using different combinations of the aforementioned models, so as to evaluate the sensitivity to boundary and initial conditions. The analysis of the cyclone thermal phase showed the presence of a deep warm-core quasi-symmetric structure, thus confirming the tropical-like nature of the system. In the Atlantic phase, the precursor, in the form of a low-pressure system, was traced from North America to the Mediterranean. The thermal phase analysis showed evidence of a deep cold-core asymmetric structure during the whole Atlantic phase, while the first contact with the Mediterranean Sea caused a sudden transition to a shallow warm-core structure. The examination of potential vorticity (PV) three-dimensional structure revealed the presence of a PV streamer that formed individually over the Labrador Sea and subsequently interacted with the low-pressure system near the northwestern coast of the Iberian peninsula, favouring the first phase of the cyclone intensification. [ABSTRACT FROM AUTHOR]

Hereditary spastic paraplegias (HSP) are a group of neurodegenerative disorders characterized by progressive lower extremity spastic weakness. SPG7, SPG4 and SPG3A are some of the autosomal genes recently found as mutated in recessive or dominant forms of HSP in childhood. SPG31 is more often associated with a pure spastic paraplegia phenotype, but genotype-phenotype correlation is still unclear. The aims of the current study was: (i) to verify the mutational frequency of SPG4, SPG3A, SPG31 and SPG7 genes in our very-well-selected childhood sample, and (ii) to improve our knowledge about the clinical and electrophysiological HSP phenotypes and their possible correlation with a specific mutation. A sample of 14 Italian children affected by pure HSP (mean age at diagnosis 5.9 years) was extensively investigated with electrophysiological, neuroradiological and genetic tests. Three SPG4 mutations were identified in three patients: two novel missense mutations, both sporadic, and one multiexonic deletion already reported. A novel large deletion in SPG31 gene involving exons 2-5 was also detected in one young patient. No mutations in the SPG7 and in the SPG3A genes were found. Our data confirm that HSP represent a heterogeneous group of genetic neurodegenerative disorders, also in sporadic or autosomal recessive early onset forms. Multiplex Ligation-dependent Probe Amplification-based mutation screening for SPG4 and SPG31 genes would be added to sequencing-based screening of SPG4, SPG31 and SPG3A genes in the routine diagnosis of HSP children. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective The occurrence of fetal intracranial hemorrhage before labor has been repeatedly observed. The aim of this study was to evaluate the sonographic appearance of fetal intracranial hemorrhage in relation to its location. Possible causative factors were also evaluated. Design Five consecutive cases of fetal intracranial hemorrhage were identified at a single ultrasound unit between 1996 and 1999. In utero magnetic resonance imaging was also performed in four of these cases. Autopsy was performed after pregnancy termination or intrauterine fetal death (one case of each), and neurological follow-up was initiated in the three surviving infants. Results Hydrocephaly was the predominant sonographic finding associated with intraventricular or subependymal hemorrhage; sonography provided the correct diagnosis in the former (two cases), whereas magnetic resonance imaging was necessary in the latter. Massive intraparenchymal hemorrhage was depicted as an irregular echoic mass, whereas extradural hemorrhage had a cystic appearance. History of minor maternal physical trauma without maternal or placental injury was elicited in all cases. Ultrasound examinations performed before or shortly after the trauma were available in all cases and showed normal fetal anatomy. Conclusions The sonographic appearance of fetal intracranial hemorrhage is variable, depending on its location. Even though sonography detected an intracranial anomaly in all cases, magnetic resonance imaging was necessary to establish the hemorrhagic nature of isolated subependymal and extradural hemorrhage. The similarity of histories involving minor maternal physical trauma in all cases, together with the absence of any known factor predisposing to fetal hemorrhage, may suggest that trauma is at least a contributing factor to the pathogenesis of fetal intracranial hemorrhage. [ABSTRACT FROM AUTHOR]

Upper gastrointestinal bleeding is a leading cause of death in patients with liver cirrhosis. In most cases haemorrhage originates from oesophageal varices or from congestive gastropathy, and the evaluation of the bleeding risk is based on oesophagogastroduodenoscopic data. The aim of this prospective study was to determine whether the measurement of portal flow velocity by Duplex-Doppler, compared with endoscopic data, can help in detecting patients with cirrhosis at risk of bleeding. One hundred and seventy-three patients underwent endoscopy to ascertain the size of the varices and the severity of congestive gastropathy. For each patient maximal portal flow velocity measurements were obtained. No difference in portal flow velocity was observed between patients with or without oesophageal varices or congestive gastropathy. During a 2-year observation period, 27 patients (15.6%) had at least one episode of acute digestive bleeding. Stepwise multiple logistic regression analysis demonstrated a correlation between oesophageal varices and congestive gastropathy endoscopic grading and the incidence of bleeding; only the former was entered into the final regression equation (p>0.001). No relationship between the max portal flow velocity value and incidence of bleeding was found. This study shows that portal flow velocity is unrelated to the degree of the endoscopic abnormalities in patients with liver cirrhosis and that it has no value in the identification of patients with cirrhosis at risk of upper gastrointestinal bleeding. [ABSTRACT FROM AUTHOR]

This study investigated whether functional transcranial Doppler ultrasound (fTCD) is a suitable tool for studying hemispheric lateralization of language in patients with pre-perinatal left hemisphere (LH) lesions and right hemiparesis. Eighteen left-hemisphere-damaged children and young adults and 18 healthy controls were assessed by fTCD and fMRI to evaluate hemispheric activation during two language tasks: a fTCD animation description task and a fMRI covert rhyme generation task. Lateralization indices (LIs), measured by the two methods, differed significantly between the two groups, for a clear LH dominance in healthy participants and a prevalent activation of right hemisphere in more than 80% of brain-damaged patients. Distribution of participants in terms of left, right, and bilateral lateralization was highly concordant between fTCD and fMRI values. Moreover, right hemisphere language dominance in patients with left hemispheric lesions was significantly associated with severity of cortical and subcortical damage in LH. This study suggests that fTCD is an easily applicable tool that might be a valid alternative to fMRI for large-scale studies of patients with congenital brain lesions., (© 2017 The British Psychological Society.)

Very little is known about the action observation network and the mirror neuron system (AON/MNS) in children and its age-related properties compared with those observed in adults. In the present fMRI study we explored the activation of areas belonging to the AON/MNS in children and adults during observation of complex hand-grasping actions, as compared to observation of simple grasping acts executed with the left and the right hand, seen from a first person perspective. The results indicate that during the action observation tasks in children there was activation of a cortical network similar to that found in adults, including the premotor cortex, the posterior part of the inferior frontal gyrus and the posterior parietal lobe. However, the activation in children was more widespread and showed a higher inter-subject variability compared with adults. Furthermore, the activated network seems more lateralized to the left hemisphere in adults and more bilateral in children, with a linear growth of lateralization index as a function of age. Finally, in children the activation in the anterior intraparietal cortex (AIP) of each hemisphere was higher during observation of the contralateral hand (hand identity effect) and during the observation of complex actions relative to simple grasping acts, confirming the role of AIP for action-related hand identity previously described in adults. These results support the assumption that structure and size of action representations are sensitive to mechanisms of development and show physiological plasticity. These properties of the AON/MNS could constitute a powerful tool for spontaneous reorganization and recovery of motor deficits after brain injury in children and in adults, as well as for specific rehabilitation programmes., (© 2015 John Wiley & Sons Ltd.)

Navigational and reaching spaces are known to involve different cognitive strategies and brain networks, whose development in humans is still debated. In fact, high-level spatial processing, including allocentric location encoding, is already available to very young children, but navigational strategies are not mature until late childhood. The Magic Carpet (MC) is a new electronic device translating the traditional Corsi Block-tapping Test (CBT) to navigational space. In this study, the MC and the CBT were used to assess spatial memory for navigation and for reaching, respectively. Our hypothesis was that school-age children would not treat MC stimuli as navigational paths, assimilating them to reaching sequences. Ninety-one healthy children aged 6 to 11 years and 18 adults were enrolled. Overall short-term memory performance (span) on both tests, effects of sequence geometry, and error patterns according to a new classification were studied. Span increased with age on both tests, but relatively more in navigational than in reaching space, particularly in males. Sequence geometry specifically influenced navigation, not reaching. The number of body rotations along the path affected MC performance in children more than in adults, and in women more than in men. Error patterns indicated that navigational sequences were increasingly retained as global paths across development, in contrast to separately stored reaching locations. A sequence of spatial locations can be coded as a navigational path only if a cognitive switch from a reaching mode to a navigation mode occurs. This implies the integration of egocentric and allocentric reference frames, of visual and idiothetic cues, and access to long-term memory. This switch is not yet fulfilled at school age due to immature executive functions., (© 2014 John Wiley & Sons Ltd.)

We report on a 9.5-year-old Italian boy affected by creatine transporter deficit (CT1), due to a de novo mutation in SLC6A8 gene. The patient was investigated by means of a comprehensive neuropsychological protocol and presented with an unusual alteration of speech and expressive-language function, associated with mental retardation, that differed from CT1 patients described to date. In particular, he exhibited a developmental apraxia of speech (DAS) with motor planning and execution deficit, while receptive language was consistent with his mental age., ((c) 2007 Wiley-Liss, Inc.)

The clinical phenotype of patients with ring chromosome 22 includes mental retardation with severe language impairment, hypotonia, and dysmorphic facial features. In recent years an increasing number of patients with microscopic as well as cryptic terminal deletion involving band 22q13 have been described and their phenotype shows clinical features overlapping with patients with ring chromosome 22. Loss of DNA in the 22q13.3 region may lead to a clinically recognizable syndrome named "22q13.3 deletion syndrome." We report a patient with a ring chromosome 22 who has hypotonia, profound mental retardation, language impairment, dysmorphic features, and behavioral disorders. To check if the critical region responsible for "22q13.3 deletion syndrome" was absent in this ring, a fluorescent in situ hybridization (FISH) analysis using a probe corresponding to the ARSA locus was performed. In our patient, only one ARSA signal could be detected, indicating that the deletion encompassed the critical 22q13.3 region. A more detailed analysis of the deletion extent then was performed using a panel of fluorescent probes located within 22q13. These experiments allowed the identification of the breakpoint between CTA-299D3 and RP5-925J7 probe, located in 22q13.32. Deletion extent could be estimated to be about 2.5 Mb, and this larger deletion may explain the severity of clinical features observed in our patient.