A 16q22.2-q23.1 deletion identified in a male infant with West syndrome

In partial monosomy of the distal part of chromosome 16q, abnormal facial features, intellectual disability (ID), and feeding dysfunction are often reported. However, seizures are not typical and the majority of them were seizure-free. Here we present the case of a 16q22.2-q23.1 interstitial deletion identified in a male patient with severe ID, facial anomalies including forehead protrusions and flat nose bridge, patent ductus arteriosus, bilateral vocal cord atresia treated by tracheotomy, and West syndrome, which were developed 10 months after birth. Although phenobarbital, sodium valproate (VPA), and zonisamide were not effective as monotherapies or combination therapies, the patient's epileptic seizures and electroencephalogram anomalies disappeared following combined therapy with lamotrigine and VPA. Although WW Domain Containing Oxidoreductase (WWOX), which is known as a cause of autosomal recessive epileptic encephalopathy, was included within the 6.8-Mb deleted region which identified by targeted panel sequencing and validated by chromosomal microarray analysis, no pathogenic variants were detected in the other allele of WWOX. Therefore, it is possible that other genes within or outside of the long deleted region or their interactions may cause West syndrome in this patient

Age-related changes in a patient with Pelizaeus-Merzbacher disease by repeated 1H-MRS

Purpose: In this report, we describe a patient with Pelizaeus-Merzbacher disease (PMD) who underwent repeated evaluations by 1H-Magnetic resonance spectroscopy (MRS). Subject: The patient was given a definitive diagnosis of PMD based on genetic testing, which showed overlap of the proteolipid protein 1 (PLP1) gene. The control subjects for 1H-MRS consisted of healthy age-matched children. Methods: All measurements were performed with a clinical 3-tesla magnetic resonance imaging (MRI) system. For 1H-MRS, the center of a voxel was positioned in the right parietal lobe. 1H-MRS was performed when the patient was 2, 6, 14, and 25 months old. Results: The concentration of GABA in early childhood (2 months 1.72 mM, 6 months 2.15 mM) was increased compared with that in normal controls. However, his GABA concentration was normalized at 14 and 25 months. The concentrations of Ins were increased after 6 months. No remarkable changes were seen in the concentration of Cho at any time. Conclusion These results suggest that the changes in metabolite concentrations during growth may reflect the pathological state of PMD. Furthermore, the lack of a change in the Cho concentration may be useful for differentiating PMD from other demyelinating diseases

A case of generalized lymphatic anomaly causing skull-base leakage and bacterial meningitis

Generalized lymphatic anomaly (GLA) is a multifocal lymphatic malformation that affects the skin, thoracic viscera, and bones. A 7-year-old boy presented with fever and disturbance of consciousness, and bacterial meningitis was diagnosed. Computed tomography and magnetic resonance imaging revealed middle skull-base leakage due to lymphatic malformation. Past history included facial palsy due to cystic tumors in the right petrous bone 4 years before onset of meningitis. At that time, pericardial effusion had been found and GLA had been diagnosed by pericardial biopsy. He achieved complete recovery under intensive care with antibiotics and mechanical ventilation. At the 3-year follow-up, the patient was healthy with no recurrence of meningitis. We should consider GLA among the differential diagnoses for osteolytic diseases in the pediatric population

Multi-delay arterial spin labeling brain magnetic resonance imaging study for pediatric autism

Introduction Arterial spin labeling (ASL) is a non-invasive magnetic resonance imaging (MRI) technique that can measure regional cerebral blood flow (rCBF) without radiation exposure. This study aimed to evaluate rCBF in individuals with autism and their age-matched controls, globally and regionally. Methods We performed ASL MRI (3T, pulsed-continuous ASL, 3 delayed ASL imaging sequences) for 33 patients with autism spectrum disorder (ASD) (average age: 7.3 years, range: 2-14 years). Nineteen children (average age: 8.6 years, range: 3-15 years) without ASD and intellectual delay were included as controls. Patients with morphological abnormalities detected on MRI were excluded. Objective analysis was performed with automatic region of interest analysis of the ASL results. The Mann-Whitney U test was used to compare the rCBF results between the groups. Results Compared to the controls, patients with ASD showed a statistically significant decrease in rCBF, respectively, in the insula [left, rCBF 51.8±9.5 mL/100 g/min (mean±SD) versus 59.9±9.8, p=0.0017; right, 51.2±10.1 versus 57.8±8.8, p=0.0354], superior parietal lobule (left, 44.6±8.4 versus 52.0±7.8, p=0.003), superior temporal gyrus (left, 50.0±8.6 versus 56.9±8.6, p=0.007; right, 49.5±8.4 versus 56.4±7.7, p=0.0058), and inferior frontal gyrus (left, 53.0±9.8 versus 59.3±9.9, p=0.0279), which are associated with the mirror neuron system. Conclusions We concluded that patients with ASD showed a statistically significant decline in CBF in regions associated with the mirror neuron system. The advantages of ASL MRI include low invasiveness (no radiation exposure) and short imaging time (approximately 5 min). Studies with larger sample sizes are required to establish the diagnostic value of ASL MRI for ASD

Suzaku Detection of Diffuse Hard X-Ray Emission outside Vela X

Vela X is a large, 3x2 degrees, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we find hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index is measured to be constant at Gamma~2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.Comment: 18 pages, 7 figures, accepted for publication in PASJ (Suzaku Special Issue

Low X-ray Efficiency of a Young High-B Pulsar PSR J1208-6238 Observed with Chandra

High magnetic field (high-B) pulsars are key sources to bridge magnetars and conventional rotation powered pulsars, and thus to understand the origin of magnetar activities. We have estimated a tight upper-limit on the X-ray flux of one of the youngest high-B pulsars PSR J1208-6238 for the first time; a Chandra 10 ks observation shows no significant source. Depending on the emission models, the 3sigma upper-limit on the intrinsic 0.5-7 keV flux to (2.2-10.0)e-14 erg/s/cm2.Comment: 7 pages, 6 figures, Ap&SS, accepte

Measuring the Broad-band X-Ray Spectrum from 400 eV to 40 keV in the Southwest Part of the Supernova Remnant RX J1713.7-3946

We report on results from Suzaku broadband X-ray observations of the southwest part of the Galactic supernova remnant (SNR) RX J1713.7-3946 with an energy coverage of 0.4-40 keV. The X-ray spectrum, presumably of synchrotron origin, is known to be completely lineless, making this SNR ideally suited for a detailed study of the X-ray spectral shape formed through efficient particle acceleration at high speed shocks. With a sensitive hard X-ray measurement from the HXD PIN on board Suzaku, we determine the hard X-ray spectrum in the 12--40 keV range to be described by a power law with photon index Gamma = 3.2+/- 0.2, significantly steeper than the soft X-ray index of Gamma = 2.4+/- 0.05 measured previously with ASCA and other missions. We find that a simple power law fails to describe the full spectral range of 0.4-40 keV and instead a power-law with an exponential cutoff with hard index Gamma = 1.50+/- 0.09 and high-energy cutoff epsilon_c = 1.2+/- 0.3 keV formally provides an excellent fit over the full bandpass. If we use the so-called SRCUT model, as an alternative model, it gives the best-fit rolloff energy of epsilon_{roll} = 0.95+/- 0.04 keV. Together with the TeV gamma-ray spectrum ranging from 0.3 to 100 TeV obtained recently by HESS observations, our Suzaku observations of RX J1713.7-3946 provide stringent constraints on the highest energy particles accelerated in a supernova shock.Comment: 11 pages, 11 figures, accepted for publication in Publications of the Astronomical Society of Japan (PASJ

Chandra View of Pulsar Wind Nebula Tori

The results from a systematic study of eleven pulsar wind nebulae with a torus structure observed with the Chandra X-ray observatory are presented. A significant observational correlation is found between the radius of the tori, r, and the spin-down luminosity of the pulsars, Edot. A logarithmic linear fit between the two parameters yields log r = (0.57 +- 0.22) log Edot -22.3 +- 8.0 with a correlation coefficient of 0.82, where the units of r and Edot are pc and ergs s^-1, respectively. The value obtained for the Edot dependency of r is consistent with a square root law, which is theoretically expected. This is the first observational evidence of this dependency, and provides a useful tool to estimate the spin-down energies of pulsars without direct detections of pulsation. Applications of this dependency to some other samples are also shown.Comment: 8 pages, 2 figures, ApJ in pres

Discovery of Extended X-Ray emission from the unidentified TeV source HESS J1614-518 using the Suzaku Satellite

We report the Suzaku results of HESS J1614-518, which is the brightest extended TeV gamma-ray source discovered in the Galactic plane survey conducted using the H.E.S.S. telescope. We discovered three X-ray objects in the field of view of the X-ray Imaging Spectrometer (XIS), which were designated as Suzaku J1614-5141 (src A), Suzaku J1614-5152 (src B), and Suzaku J1614-5148 (src C). Src A is an extended source located at the peak position of HESS J1614-518, and therefore it is a plausible counterpart to HESS J1614-518. The X-ray flux in the 2-10 keV band is 5e-13 erg/s/cm^2, which is an order of magnitude smaller than the TeV flux. The photon index is 1.7, which is smaller than the canonical value of synchrotron emissions from high-energy electrons found in some supernova remnants. These findings present a challenge to models in which the origin of the TeV emission is the inverse Compton scattering of the cosmic microwave background by accelerated electrons that emit X-rays via synchrotron emission. Src B is located at a relatively dim region in the TeV band image; however, its hydrogen column density is the same as that of src A. Therefore, src B may also be physically related to HESS J1614-518. Src C is a foreground late-type B star. We also discovered a soft extended X-ray emission near HESS J1614-518.Comment: Accepted for publication in PASJ vol. 60 Suzaku Special Issue