Genetic landscape of Rett syndrome-like phenotypes revealed by whole exome sequencing.

BACKGROUND: Rett syndrome (RTT) is a characteristic neurological disease presenting with regressive loss of neurodevelopmental milestones. Typical RTT is generally caused by abnormality of methyl-CpG binding protein 2 (MECP2). Our objective to investigate the genetic landscape of MECP2-negative typical/atypical RTT and RTT-like phenotypes using whole exome sequencing (WES). METHODS: We performed WES on 77 MECP2-negative patients either with typical RTT (n=11), atypical RTT (n=22) or RTT-like phenotypes (n=44) incompatible with the RTT criteria. RESULTS: Pathogenic or likely pathogenic single-nucleotide variants in 28 known genes were found in 39 of 77 (50.6%) patients. WES-based CNV analysis revealed pathogenic deletions involving six known genes (including MECP2) in 8 of 77 (10.4%) patients. Overall, diagnostic yield was 47 of 77 (61.0 %). Furthermore, strong candidate variants were found in four novel genes: a de novo variant in each of ATPase H+ transporting V0 subunit A1 (ATP6V0A1), ubiquitin-specific peptidase 8 (USP8) and microtubule-associated serine/threonine kinase 3 (MAST3), as well as biallelic variants in nuclear receptor corepressor 2 (NCOR2). CONCLUSIONS: Our study provides a new landscape including additional genetic variants contributing to RTT-like phenotypes, highlighting the importance of comprehensive genetic analysis.

Factors associated with sleep duration among pupils.

BACKGROUND: Sleep shortage has been pervasive among pupils. METHODS: Multiple regression analysis was used to analyze 2,722 questionnaires obtained from grade 5 to 12 pupils, to determine factors associated with sleep duration. RESULTS: Significant regression formulae for sleep duration were obtained for all school types: adjusted R2 / P value were 0.14/<0.001 for elementary school; 0.11/<0.001 for junior high school; 0.06/<0.001 for high school. Longer after-school activities (standardized regression coefficient/ P value were -0.22/<0.001 for elementary school; -0.10/<0.01 for junior high school; -0.18/<0.001 for high school) and more sleepiness (-0.09/<0.001 for elementary school; -0.07/<0.05 for junior high school; -0.07/<0.05 for high school) were significantly associated with reduced sleep duration for all school types. In both elementary and junior high schools, the higher grade (-0.53/<0.001 for elementary school; -0.10/<0.01 for junior high school), and longer weekday screen time (-0.15/<0.001 for elementary school; -0.19/<0.001 for junior high school) were also significantly associated with sleep loss. In elementary school, irregular dinner (-0.07/<0.05), breakfast skipping (-0.11/<0.001), longer weekend screen time (-0.09/<0.05) and better self-reported academic performance (0.07/<0.05) also revealed significant associations with sleep loss. In high school, reduction of sleep duration was also significantly associated with higher standardized body mass index (-0.08/<0.05). CONCLUSIONS: Excessive after-school activity might be considered in association with pupils' sleep reduction.

Insufficient sleep syndrome: An unrecognized but important clinical entity.

BACKGROUND: A sleep clinic for adults and children was established in the Tokyo Bay Urayasu Ichikawa Medical Centre, in August 2012. Given that few sleep clinics are available in Japan specifically for children, this clinic provides the opportunity to provide data on child patients with sleep problems. METHODS: Records of patients who visited the sleep clinic at the Tokyo Bay Urayasu Ichikawa Medical Centre aged ≤20 years at the first visit were retrospectively examined, along with the initial and final diagnoses. RESULTS: Of 2,157 patients who visited the sleep clinic at Tokyo Bay Urayasu Ichikawa Medical Centre between August 2012 and March 2017, 181 were ≤20 years old. In these 181 patients, the most frequent final diagnosis was insufficient sleep syndrome (ISS), n = 56, followed by circadian rhythm sleep-wake disorder, n = 28; insomnia, n = 28; and sleep-related movement disorder, n = 15. CONCLUSIONS: Insufficient sleep produces various brain dysfunctions in both adults and children, and is associated with behavioral, cognitive and physical problems, as well as with atypical early development. Insufficient sleep has also been reported to cause obesity. Insufficient sleep-induced obesity is often associated with the occurrence of metabolic syndrome. More effort is needed to ensure that children are receiving sufficient sleep.

E2A and CBP/p300 act in synergy to promote chromatin accessibility of the immunoglobulin κ locus.

V(D)J recombination of Ig and TCR genes is strictly regulated in a lineage- and stage-specific manner by the accessibility of target gene chromatin to the recombinases RAG1 and RAG2. It has been shown that enforced expression of the basic helix-loop-helix protein, E2A, together with RAG1/2 in a nonlymphoid cell line BOSC23 can induce V(D)J recombination in endogenous Igκ and TCR loci by increasing chromatin accessibility of target gene segments. In this study, we demonstrate that ectopically expressed E2A proteins in BOSC23 cells have the ability to bind directly to the promoter and recombination signal sequence of Vκ genes and to recruit histone acetyltransferase CBP/p300. Overexpression of CBP/p300 in conjunction with E2A results in enhancement of E2A-induced histone acetylation, germline transcription, and Igκ rearrangement. Conversely, knockdown of endogenous CBP/p300 expression by small interfering RNA leads to a decrease in histone acetylation, germline transcription and Igκ rearrangement. Furthermore, analyses using a mouse pre-B cell line revealed that endogenous E2A proteins also bind to a distinct set of Vκ genes and regulatory regions in the mouse Igκ locus and act to increase histone acetylation by recruiting p300, confirming the similar findings observed with BOSC23 cells. These observations indicate that E2A plays critical roles in inducing Igκ rearrangement by directly binding to and increasing chromatin accessibility at target gene segments.

Development of Surgical System Using Bellows-Type Foldable Five-Fingered Robot Hand Inserted through a 20-mm Port.

The purpose of this study was to develop a robotic hand to assist with large organs, instead of using a surgeon, in laparoscopic surgery. Grasping, pinching, and exclusion were performed by three subjects with no medical knowledge. The results indicate that the proposed system can perform surgical operations in hand-assisted laparoscopic surgery when the subjects are proficient. However, the thumb mechanism and the wrist control method were required improvement because it was difficult to approach organs. Surgeons were asked to operate the robotic hand while watching the laparoscope image, and they were able to grasp and pinch with little practice.

Zonisamide eradicated paroxysmal headache with EEG abnormalities triggered by hypertensive encephalopathy due to purpura nephritic syndrome.

Generally, prognosis of hypertensive encephalopathy in childhood is favorable. We reported a 5-year-old girl who presented with a headache attack and EEG abnormalities after hypertensive encephalopathy due to purpura nephritis. The patient had suffered from hypertensive encephalopathy due to purpura nephritis, which soon ameliorated. Five months later, she developed attacks of headache, vomiting and disturbed consciousness with left side-predominant EEG abnormalities. Although carbamazepine and sodium valproate failed to improve her condition, zonisamide eradicated both the symptoms and EEG abnormalities, and an attack has not reoccurred for 5 years since completion of her treatment. It is noteworthy that delayed-onset complications can occur in child hypertensive encephalopathy, cases of which should be followed up prudently. Zonisamide should be considered for treatment of attacks of headaches with an epileptic character.

Protracted juvenile neuronal ceroid lipofuscinosis--an autopsy report and immunohistochemical analysis.

The juvenile form of neuronal ceroid lipofuscinosis (JNCL) is caused by mutations in the CLN3 gene, and is characterized by progressive loss of vision and development of motor deficits. A few patients exhibit a more protracted clinical course and are diagnosed with protracted JNCL (PJNCL). Here, we report the autopsy in a case of PJNCL in a 55-year-old male and immunohistochemical examination of the involvement of oxidative stress and glutamate excitotoxicity in neurodegeneration. The patient was born to consanguineous parents (I assume this means that the parents were related. If not, then the sentence will need to be changed again.) and had brothers with similar neurological disease. He showed mental retardation and visual impairment in the first decade which gradually developed along with motor dysfunction for over 40 years. At autopsy, the cerebral pyramidal neurons revealed deposition of lipopigments, which demonstrated 'finger print' and curvilinear profiles on electron microscopy. He also exhibited cerebellar cortical atrophy, fibrillary gliosis in the white matter, and rarefication in the globus pallidus. Immunohistochemically, the number of neurons immunoreactive for advanced glycation end product was elevated in the cerebellar cortex and midbrain. Immunoreactivity for excitatory amino acid transporter 1 was reduced in the cerebellar dentate and inferior olivary nuclei. These findings suggest that oxidative damage to proteins and disturbed glutamate transport can be involved in PJNCL.

Fluctuating hearing loss, episodic headache, and stroke with platelet hyperaggregability: coexistence of auditory neuropathy and cochlear hearing loss.

We encountered a 10-year-old girl with fluctuating sensorineural hearing loss, episodic headache, and white matter stroke. Strenuous exercise, febrile illness, and general anesthesia all temporarily worsened hearing. Audiologic findings were asymmetric: left-sided retrocochlear dysfunction consistent with auditory neuropathy contrasted with cochlear hearing loss in the right ear. Platelets obtained during a headache-free period showed excessive responsiveness to collagen in vitro, while episodic elevations of thromboxane B(2) and thrombin-antithrombin III complex were noted in blood sampled during headache. Treatment of hyperaggregability of platelets with aspirin and antioxidant vitamins relieved headache, while adenosine triphosphate administration improved hearing thresholds. In this patient, hearing impairment and white matter strokes appeared to respectively related to impaired blood flow to the cochlea and white matter caused by platelet dysfunction triggered by physiologic stresses.

[Treatment of sleep apnea syndrome in a Down syndrome patient with behavioral problems by noninvasive positive pressure ventilation: a successful case report].

The use of noninvasive positive pressure ventilation (NPPV) is increasingly accepted as a treatment of respiratory problems in patients with neuromuscular disease. However, its use in mentally retarded and un-cooperative patients has not been reported. We report here the evaluation and treatment of sleep apnea in a Down syndrome patient. After recovering from a life threatening respiratory failure the patient had persistent sleep apnea syndrome. Limited examinations disclosed that he had two types of apnea; obstructive and central type apnea. Our treatment was a diet with intake restricted up to 1,000 kcal per day for the obstructive apnea, and NPPV with low dosage of oxygen for the obstructive and central apnea. With these treatments in one year's hospitalization, his quality of life was significantly improved. He has continued the treatment in the outpatient department and enjoys a better quality of life both at home and in the community. The successful treatment of this case may become an example of the more extensive use of NPPV for such respiratory problems in handicapped children and adults with behavioral problems.

Clinical and genetic features of acute encephalopathy in children taking theophylline.

BACKGROUND: Theophylline has recently been suspected as a risk factor of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD), although there has been no systematic study on the relationship between acute encephalopathy in children taking theophylline (AET) and AESD. METHODS: We recruited 16 Japanese patients (11 male and 5 female, median age of 2 years and 7 months) with AET from 2008 to 2013. We evaluated their clinical features, such as the duration of first seizure, biphasic clinical course and cranial CT/MRI imaging and compared them with those of AESD. We analyzed the polymorphisms or mutations of genes which are associated with AESD. RESULTS: Clinically, 12 patients had neurological and/or radiological features of AESD. Only one patient died, whereas all 15 surviving patients were left with motor and/or intellectual deficits. Genetically, 14 patients had at least one of the following polymorphisms or mutations associated with AESD: thermolabile variation of the carnitine palmitoyltransferase 2 (CPT2) gene, polymorphism causing high expression of the adenosine receptor A2A (ADORA2A) gene, and heterozygous missense mutation of the voltage gated sodium channel 1A (SCN1A) and 2A (SCN2A) gene. CONCLUSIONS: Our results demonstrate that AET overlaps with AESD, and that AET is a multifactorial disorder sharing a genetic background with AESD.

[An infant with diffuse axonal injury].

Development of MRI enabled accurate and rapid diagnosis of head traumas which had been impossible with the conventional CT. The diagnosis of posttraumatic diffuse axonal injury (DAI) is a typical example. Most of the reported cases of DAI in childhood are of relatively older age, and DAI is rare in infancy. We report here a 1-year-9-month-old infant with DAI. After falling from two meters in height, he presented consciousness disturbance and a seizure that necessitated artificial respiration for half a day. He recovered completely without sequelae. Brain CT on arrival to the ER department was unremarkable, but MRI scans shortly thereafter showed typical findings of DAI. In childhood, DAI tends to be milder than in adult-hood, which may be explained by the age-dependent frequency of traffic accidents, and by anatomical and functional factors of a infant's brain. A large number of infantile cases should be accumulated to draw a more clearcut conclusion.

The pedunculopontine nucleus in developmental disorders of the basal ganglia.

The pedunculopontine nucleus (PPN), which is located in the upper brainstem, contains cholinergic and non-cholinergic neurons, and has afferent and efferent connections to the basal ganglia and spinal cord. The PPN is known to be affected in adult-onset basal ganglia diseases, and we speculated that the PPN might be similarly insulted in developmental basal ganglia disorders. We immunohistochemically examined the expression patterns of acetylcholine esterase and tyrosine hydroxylase, markers of acetylcholinergic and catecholaminergic neurons, respectively, in the PPN pars dissipata (PPNd) of controls and patients with bilirubin encephalopathy (BE) and perinatal hypoxic ischemic encephalopathy with localized basal ganglia lesion (HIEbg). Controls showed an age-dependent change in the percentages of acetylcholinergic and catecholaminergic neurons. Three out of six BE cases and three out of six HIEbg cases showed a reduction in the percentage of acetylcholinergic neurons in the PPNd. Additionally, three BE cases demonstrated an increase in the percentage of catecholaminergic neurons. It is likely that the relative proportions of acetylcholinergic and catecholaminergic neurons in the PPN can be altered in developmental basal ganglia disorders.