Dynamic X-Ray Diffraction Technique for Measuring the Crystal Lattice Response in Semicrystalline Polymers against Mechanical Excitations

Dynamic mechanical and crystallographic features which are associated with mechanical excitations on the bulk specimen of the semicrystalline polymers are generalized on the basis of factors such as mechanical dispersions of orientation of crystallites and deformation of the crystal superstructure. The latter factor may further be divided into inter-lamellae and intra-lamella responses within the superstructure such as spherulite. The present paper describes the theory and techniques set up to observe the intralamella response in the semicrystalline polymers against mechanical excitations by means of a dynamic x-ray diffraction technique. This observation is required to measure the inphase and out-of-phase components of the angular vibration of the diffraction maximum raised by the forced sinusoidal strain of the test specimen. For this purpose, it was shown that a twin detector technique could successfnlly be applicable where the diffraction peak shift was amplified by simultaneous measurements of the shoulder intensities of the diffraction perk at the higher and the lower diffraction angles to the peak maximum

Dynamic X-ray Diffraction Technique for Measuring Rheo-optical Properties of Crystalline Polymeric Materials

A dynamic X-ray diffraction technique, which can follow the responses of polymer crystals (crystallization, orientation, and lattice deformation) to a mechanical excitation of sinusoidal strain induced to a bulk specimen, was described. The descriptions for such responses are qualitatively made by using a narrow sector technique, which can measure the X-ray diffraction intensity distribution at a particular phase angle of the sinusoidal strain as a function of static and dynamic strains, temperature, and angular frequency. A typical result is demonstrated in terms of the investigation of orientationcrystallization phenomena of natural rubber vulcanizates. More quantitative descriptions can be made by using a half-circle sector technique, which can measure the in-phase and out-of phase components of the dynamic X-ray diffraction intensity distribution. From these, one can obtain the dynamic strain-induced crystallization and orientation coefficients and the dynamic response of lattice deformation of a specific crystal plane both as functions of temperature and frequency. After a brief survey of the principle of the half-circle sector technique, frequency dependence of the dynamic strain-induced crystallization coefficients of the (002) and (200) crystal planes of natural rubber vulcanizates is demonstrated in terms of the two frequency dispersion regions around 10⁻² and 10¹ Hz at a room temperature. The former and latter dispersions must be correlated with the crystallization processes of the so-called α- and γ-filaments, respectively. In addition, frequency and temperature dispersions of the dynamic strain-induced orientation coefficient and the dynamic response of lattice deformation of the (110) crystal plane of polyethylene are demonstrated in relation to the so-called a₁ and a₂ dispersions of dynamic mechanical modulus function of this material

Effective treatment of a 13-year-old boy with steroid-dependent ocular myasthenia gravis using tacrolimus

Over the past several years, tacrolimus has attracted attention as a new therapeutic drug for myasthenia gravis (MG), but few reports have considered its use for MG in pediatric patients, and most of these have focused on severe systemic MG. In this case report, we used tacrolimus to successfully treat a 13-year-old boy with ocular MG who had suffered from severe steroid complications, including a failure of thrive and osteoporosis. He first showed symptoms of ocular MG at age 2 years 3 months. At age 13 years, he was receiving PSL (3.75 mg/day), but the symptoms of ocular MG recurred. We increased the dosage of oral PSL up to 30 mg/day, and three courses of mPSL pulse therapy were applied, but these therapies had only limited effect, and his symptoms worsened. Tacrolimus was started at 0.4mg/day (0.011mg/kg/day), and every two weeks the dose was gradually increased by 0.2mg/day. His symptoms of MG began to improve three weeks after the initial administration of tacrolimus. Approximately three months after the start of tacrolimus administration, PSL was discontinued. Currently, at one year and four months after the start of tacrolimus administration, while slight ptosis is observed in the evening, it does not influence his daily life, and his condition remains comparable to that when he stopped taking PSL. No adverse effects of tacrolimus have been recognized. In pediatric patients with steroid-dependent ocular MG without thymectomy, tacrolimus may be a safe and effective alternative to steroid and thymectomy

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

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

Chromosome 1p36 deletion syndrome detected by NGS

Although chromosome 1p36 deletion syndrome is considered clinically recognizable based on characteristic features, the clinical manifestations of patients during infancy are often not consistent with those observed later in life. We report a 4-month-old girl who showed multiple congenital anomalies and developmental delay, but no clinical signs of syndromic disease caused by a terminal deletion in 1p36.32-p36.33 that was first identified by targeted-exome sequencing for molecular diagnosis

Findings of brain 99mTc-ECD SPECT in high-functioning autism : 3-dimensional stereotactic ROI template analysis of brain SPECT

The aim of this study is confirmation of an abnormal regional cerebral blood flow (rCBF) pattern in high-functioning autism (HFA). Confirmation of an abnormal rCBF pattern in HFA may be useful for elucidate of its pathophysiology and a differential diagnosis, such as with attention-deficit / hyper activity disorder (AD/HD).Brain 99mTc-ECDSPECTwas performed in 16 cases of HFA. The HFA group consisted of 16 cases of HFA. They were all male, with an IQ of 76～126. They had normal brain MRI findings, and had an age of 9～14 years. We examined abnormal rCBF in HFA by comparing the results to those in the control group. The control group consisted of 1male and 4 females cryptogenic epilepsy patients with normal intelligence. They have no problems in learning at school or mental or behavioral traits. They had normal brain MRI or SPECT findings, and had an age of 7～15 years. 3-dimensional stereotactic ROI template (3DSRT) was used to analyze SPECT data. We calculated the ‘relative rCBF (%)’ (RI count of each segment ×100 / Sum of RI count of the corresponding hemisphere), and compared the values between the two groups. We found a significantly low ‘relative rCBF (%)’ in the left temporal region in the HFA group. We also calculated the ‘L/R ratio’ (the ‘relative rCBF(%)’ of a segment on the left side / the ‘relative rCBF (%)’ of the corresponding segment on the right side), and compared the value for each segment between the two groups. There were no significant differences in any segments between the two groups. We also checked for differences in the ‘relative rCBF (%)’ between segments on the right side and corresponding segments on the left side in both the HFA and control groups. We found significant rightltleft perfusion in the angular region and significant leftltright perfusion in the pericallosal, thalamus, and hippocampus region in the HFA group. We also found significant rightltleft perfusion in the temporal region in the control group. Significant hypoperfusion in the left temporal region due to an unidentified underlying brain pathology and abnormal laterality in the angular, temporal (lack of rightltleft perfusion), pericallosal, thalamus, and hippocampus regions may influence the symptoms of autism

NGS utility for diagnosis of MCA/ID

Background : In clinical practice, a large proportion of patients with multiple congenital anomalies and/or intellectual disabilities (MCA/ID) lacks a specific diagnosis. Recently, next-generation sequencing (NGS) has become an efficient strategy for genetic diagnosis of patients with MCA/ID. Objective : To review the utility of NGS for the diagnosis of patients with MCA/ID. Method : Patients with MCA/ID were recruited between 2013 and 2017. Molecular diagnosis was performed using NGS-based targeted panel sequencing for 4,813 genes. Promising causative variants underwent confirmation by Sanger sequencing or chromosomal microarray. Results : Eighteen patients with MCA/ID were enrolled in this study. Of them, 8 cases (44%) were diagnosed by targeted panel sequencing. Most of diagnosed patients were able to receive better counseling and more appropriate medical management. Conclusion : NGS-based targeted panel sequencing seems to be an effective testing strategy for diagnosis of patients with MCA/ID

MRS Study of ACC in Asperger's Syndrome

Purpose Proton magnetic resonance spectroscopy (1H MRS) is a noninvasive neuroimaging method to quantify biochemical metabolites in vivo and it can serve as a powerful tool to monitor neurobiochemical profiles in the brain. Asperger's syndrome (AS) is a type of autism spectrum disorder, which is characterized by impaired social skills and restrictive, repetitive patterns of interest and activities, while intellectual levels and language skills are relatively preserved. Despite clinical aspects have been well-characterized, neurometabolic profiling in the brain of AS remains to be clear. The present study used proton magnetic resonance spectroscopy (1H MRS) to investigate whether pediatric AS is associated with measurable neurometabolic abnormalities that can contribute new information on the neurobiological underpinnings of the disorder. Methods Study participants consisted of 34 children with AS (2-12 years old; mean age 5.2 (±2.0); 28 boys) and 19 typically developed children (2-11 years old; mean age 5.6 (±2.6); 12 boys) who served as the normal control group. The 1H MRS data were obtained from two regions of interest: the anterior cingulate cortex (ACC) and left cerebellum. Results In the ACC, levels of N-acetylaspartate (NAA), total creatine (tCr), total choline-containing compounds (tCho) and myo-Inositol (mI) were significantly decreased in children with AS compared to controls. On the other hand, no significant group differences in any of the metabolites were found in the left cerebellum. Neither age nor sex accounted for the metabolic findings in the regions. Conclusion The finding of decreased levels of NAA, tCr, tCho, and mI in the ACC but not in left cerebellar voxels in the AS, suggests a lower ACC neuronal density in the present AS cohort compared to controls