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An adult female patient was diagnosed with arginase 1 deficiency (ARG1-D) at 4 years of age, and had been managed with protein restriction combined with sodium benzoate therapy. Though the treatment was successful in ameliorating hyperammonemia, hyperargininemia persisted. After being under control with a strict restriction of dietary protein, severe fall of serum albumin levels appeared and her condition became strikingly worsened. However, after sodium phenylbutyrate (NaPB) therapy was initiated, the clinical condition and metabolic stability was greatly improved. Current management of ARG1-D is aimed at lowering plasma arginine levels. The nitrogen scavengers, such as NaPB can excrete the waste nitrogen not through the urea cycle but via the alternative pathway. The removal of nitrogen via alternative pathway lowers the flux of arginine in the urea cycle. Thereby, the clinical complications due to insufficient amount of protein intake can be prevented. Thus, NaPB therapy can be expected as a useful therapeutic option, particularly in patients with ARG1-D.

Therapeutic hypothermia following neonatal encephalopathy is neuroprotective. However, approximately one in two cooled infants still die or develop permanent neurological impairments. Further understanding of variables associated with the effectiveness of cooling is important to improve the therapeutic regimen. To identify clinical factors associated with short-term outcomes of cooled infants, clinical data of 509 cooled infants registered to the Baby Cooling Registry of Japan between 2012 and 2014 were evaluated. Independent variables of death during the initial hospitalization and survival discharge from the cooling hospital at ≤28 days of life were assessed. Death was associated with higher Thompson scores at admission (p

If the brain structure is assessed at neonatal intensive care units, covert clinical events related with subtle brain injury might be identified. The reduced scattering coefficient of near-infrared light (μS’) obtained using time-resolved near-infrared spectroscopy from the forehead of infants is associated with gestational age, body weight and Apgar scores, presumably reflecting subtle changes of the brain related to foetal growth and birth transition. One hundred twenty-eight preterm and term infants were studied to test whether μS’ obtained from the head at term-equivalent age is associated with foetal growth, birth transition and nutritional status after birth, which are key independent variables of developmental outcomes. As potential independent variables of μS’, birth weight, Apgar scores, age at full enteral feeding and post-conceptional age at the study were assessed to represent foetal growth, birth transition and nutritional status after birth. Subsequently, higher μS’ values were associated with higher Apgar scores (p = 0.003) and earlier establishment of enteral feeding (p

For infants with acute progressive hydrocephalus, invasive drainage of cerebrospinal fluid (CSF) is performed until a ventriculo-peritoneal shunt can be inserted. Surrogate markers of intracranial pressure (ICP) may help optimise the timing of invasive procedures. To assess whether RI with/without fontanel compression helps distinguish between infants with normal (2O), mild (5–11 cmH2O), and moderate (>11 cmH2O) ICP elevation, 74 ICP measures before/after CSF removal and 148 related Doppler measures of the middle cerebral artery were assessed. Higher RI was associated with fontanel compression, elevated ICP, and their interaction (all p

Many extremely preterm infants (born before 28 gestational weeks [GWs]) develop cognitive impairment in later life, although the underlying pathogenesis is not yet completely understood. Our examinations of the developing human neocortex confirmed that neuronal migration continues beyond 23 GWs, the gestational week at which extremely preterm infants have live births. We observed larger numbers of ectopic neurons in the white matter of the neocortex in human extremely preterm infants with brain injury and hypothesized that altered neuronal migration may be associated with cognitive impairment in later life. To confirm whether preterm brain injury affects neuronal migration, we produced brain damage in mouse embryos by occluding the maternal uterine arteries. The mice showed delayed neuronal migration, ectopic neurons in the white matter, altered neuronal alignment, and abnormal corticocortical axonal wiring. Similar to human extremely preterm infants with brain injury, the surviving mice exhibited cognitive deficits. Activation of the affected medial prefrontal cortices of the surviving mice improved working memory deficits, indicating that decreased neuronal activity caused the cognitive deficits. These findings suggest that altered neuronal migration altered by brain injury might contribute to the subsequent development of cognitive impairment in extremely preterm infants.

Mutations in GABRG2, which encodes the γ2 subunit of GABAA receptors, can cause both genetic epilepsy with febrile seizures plus (GEFS+) and Dravet syndrome. Most GABRG2 truncating mutations associated with Dravet syndrome result in premature termination codons (PTCs) and are stably translated into mutant proteins with potential dominant-negative effects. This study involved search for mutations in candidate genes for Dravet syndrome, namely SCN1A, 2A, 1B, 2B, GABRA1, B2, and G2. A heterozygous nonsense mutation (c.118C>T, p.Q40X) in GABRG2 was identified in dizygotic twin girls with Dravet syndrome and their apparently healthy father. Electrophysiological studies with the reconstituted GABAA receptors in HEK cells showed reduced GABA-induced currents when mutated γ2 DNA was cotransfected with wild-type α1 and β2 subunits. In this case, immunohistochemistry using antibodies to the α1 and γ2 subunits of GABAA receptor showed granular staining in the soma. In addition, microinjection of mutated γ2 subunit cDNA into HEK cells severely inhibited intracellular trafficking of GABAA receptor subunits α1 and β2, and retention of these proteins in the endoplasmic reticulum. The mutated γ2 subunit-expressing neurons also showed impaired axonal transport of the α1 and β2 subunits. Our findings suggested that different phenotypes of epilepsy, e.g., GEFS+ and Dravet syndrome (which share similar abnormalities in causative genes) are likely due to impaired axonal transport associated with the dominant-negative effects of GABRG2.

Background Proteolipid protein 1 gene ( PLP1 ) mutations result in a continuum of neurological findings characterized by X-linked hypomyelinating leukodystrophies of the central nervous system, from mild spastic paraplegia type 2 to severe Pelizaeus–Merzbacher disease. Patients We report spastic paraplegia type 2 in three individuals in one family. A 29-year-old man developed progressive spastic quadriplegia from early childhood with dysarthria, ataxia, dysphagia, and intellectual delay, but he displayed no nystagmus. His mother developed adult-onset mild spastic diplegia with dementia developing in later life, whereas his sister exhibited spastic diplegia from childhood, complicated by motor developmental delay and dysphagia. All three individuals had initially mild but progressive neurological phenotypes, no nystagmus, normal brainstem auditory-evoked potentials, and demyelinating peripheral neuropathy, but with varying clinical severity. Results A 33-kb deletion encompassing exon 2 to 7 of PLP1 was identified in all three patients. Cloning of the junction fragment of the genomic recombination revealed a short palindromic sequence at the distal breakpoint, potentially facilitating a double-strand deoxyribonucleic acid break, followed by nonhomologous end joining. X-inactivation study and sequencing of the undeleted PLP1 alleles failed to explain the differences in severity between the two female patients. Conclusions PLP1 partial deletion is a rare cause of spastic paraplegia type 2 and exhibits X-linked dominant inheritance with variable expressivity.

We studied the altered molecular species of lipids in brain and liver tissues, and fibroblasts from patients with Zellweger syndrome (ZS). ZS cerebellum samples contained a higher amount of sphingomyelin with shorter chain fatty acids compared to that in normal controls. The amount of phosphatidylethanolamine (PE) was less than half of that in controls, with the absence of the PE-type of plasmalogen. Gangliosides were accumulated in the brains and fibroblasts of ZS patients. To investigate whether or not impaired beta-oxidation of very long chain fatty acids and/or plasmalogen synthesis affects glycolipids metabolism, RNAi of peroxisomal acylCo-A oxidase (ACOX1) and glyceronephosphate O-acyltransferase (GNPAT) was performed using cultured neural cells. In neuronal F3-Ngn1 cells, ACOX1 and GNPAT silencing up-regulated ceramide galactosyltransferase (UGT8) mRNA expression, and down-regulated UDP-glucose ceramide glucosyltransferase (UGCG). These results suggest that both impaired beta-oxidation of very long chain fatty acids and plasmalogen synthesis affect glycolipid metabolism in neuronal cells.

PURPOSE The level of residual cognitive function in patients with early brain injury is a key factor limiting rehabilitation and the quality of life. Although understanding residual function is necessary for appropriate rehabilitation, the extent of its effects on cognitive improvement remains unknown. This study evaluated cognitive function in patients with severe motor and intellectual disabilities after early brain injuries due to cerebral hemorrhage or periventricular leukomalacia. We focused on neural responses to hearing the subject's own name (SON). According to previous studies, differences in response to SON are associated with several types of cognitive dysfunction. METHODS We examined healthy subjects (aged 21.4 ± 1.10 years; control) and patients with a previous brain injury (aged 13-27 years at the time of our analysis) resulting in periventricular leukomalacia or a cerebral hemorrhage during the perinatal period or childhood. We recorded EEG responses to the SON and to other Japanese words, obtaining EEG-evoked potentials with wavelet transformations. RESULTS Compared with healthy controls, beta power (not alpha power) revealed differences in response to SON by patients with brain injury, especially those with cerebral hemorrhage. CONCLUSIONS We suggest that alpha and beta power differences reflect different cognitive functions and that the SON response reveals more than one process. Beta powers may reflect the intellectual disability of cognitive function in response to self-relevant stimuli, especially in patients with cerebral hemorrhage. Meanwhile, alpha powers did not differ from those of the healthy controls, suggesting that the patients perhaps paid attention to their own names.

MRI of preterm infants at term commonly reveals subtle brain lesions such as diffuse white matter injury, which are linked with later cognitive impairments. The timing and mechanism of such injury remains unclear. The reduced scattering coefficient of near-infrared light (μs’) has been shown to correlate linearly with gestational age in neonates. To identify clinical variables associated with brain μs’, 60 preterm and full-term infants were studied within 7 days of birth. Dependence of μs’ obtained from the frontal head on clinical variables was assessed. In the univariate analysis, smaller μs’ was associated with antenatal glucocorticoid, emergency Caesarean section, requirement for mechanical ventilation, smaller gestational age, smaller body sizes, low 1- and 5-minute Apgar scores, higher cord blood pH and PO2, and higher blood HCO3− at the time of study. Multivariate analysis revealed that smaller gestational age, requirement for mechanical ventilation, and higher HCO3− at the time of study were correlated with smaller μs’. Brain μs’ depended on variables associated with physiological maturation and pathological conditions of the brain. Further longitudinal studies may help identify pathological events and clinical conditions responsible for subtle brain injury and subsequent cognitive impairments following preterm birth.

Regional brain sizes of very-preterm infants at term-equivalent age differ from those of term-born peers, which have been linked with later cognitive impairments. However, dependence of regional brain volume loss on gestational age has not been studied in detail. To investigate the spatial pattern of brain growth in neonates without destructive brain lesions, head MRI of 189 neonates with a wide range of gestational age (24–42 weeks gestation) was assessed using simple metrics measurements. Dependence of MRI findings on gestational age at birth (Agebirth) and the corrected age at MRI scan (AgeMRI) were assessed. The head circumference was positively correlated with AgeMRI, but not Agebirth. The bi-parietal width, deep grey matter area and the trans-cerebellar diameter were positively correlated with both Agebirth and AgeMRI. The callosal thickness (positive), atrial width of lateral ventricle (negative) and the inter-hemispheric distance (negative) were exclusively correlated with Agebirth. The callosal thickness and cerebral/cerebellar transverse diameters showed predominant dependence on Agebirth over AgeMRI, suggesting that brain growth after preterm-birth was considerably restricted or even became negligible compared with that in utero. Such growth restriction after preterm birth may extensively affect relatively more matured infants, considering the linear relationships observed between brain sizes and Agebirth.

Objective To determine the morphological characteristics and pathogenic factors of cerebellar injury in extremely low birth weight infants (ELBWI). Subjects and methods Neuroimaging examination was performed on 17 eligible surviving ELBWI. Their MR images were assessed and classified its pattern of cerebellar injuries. Brain pathology was examined on 15 patients, who isolated this neuroimaging subjects. The trend of brain pathologies was revealed. Results Four types of morphological pattern were recognized: (i) the absence of major portions in the cerebellum (6/17 cases); (ii) focal cerebellar tissue loss (2/17); (iii) unilateral cerebellar atrophy/hypoplasia (3/17); (iv) small cerebellum with entrapped fourth ventricle (6/17). In cerebellar pathology, the most common findings were focal or widespread cerebellar subarachnoid hemorrhage (12/15) and olivocerebellar degeneration (12/15). In addition, one-third of the cases indicated remote cerebellar parenchymal hemorrhage. Conclusion In MRI-defined lesions, the absence of major portions or focal tissue loss was associated with cerebellar parenchymal hemorrhage and/or hemorrhagic infarction, that is destructive lesion. On the other hand, small cerebellum or unilateral atrophy/hypoplasia, that is impaired development, may be related to the cerebellar neuron loss due to hemosiderin deposits in the surface of the cerebellum. The cerebellar injury in ELBWI is probably caused by not only environmental factors such as hemorrhage, hypoxia-ischemia, or other deleterious effect, but also immaturity of the rapidly growing cerebellum in particular gestational age.

OBJECTIVE: A prospective study was performed to assess the relationship between the appearance of cerebral MRI at term and the cognitive functioning at 9 years old in very preterm born infants. METHODS: Seventy-six very preterm born infants (birth weight RESULTS: Mildly low scores on the different IQ indices ( CONCLUSIONS: In a cohort of very preterm born infants, abnormal white matter appearance on term MRI showed consistent associations with cognitive impairments at 9 years old, further supporting the benefit of obtaining term MRI for very preterm born infants.

Background: In order to clarify the correlation between morphological characteristics and clinical features in epilepsy patients with unilateral hippocampal abnormality, morphological and morphometric magnetic resonance imaging studies were performed. Methods: We selected a series of childhood-onset epilepsy patients with unilateral hippocampal abnormality. The volume of hippocampal formation and anterior temporal lobe were measured, and the hippocampal morphology was compared with their clinical features. The morphological characteristics of the hippocampal formation were classified into three groups: group I, diffuse and severe volume reduction of the hippocampal formation and anterior temporal lobe with abnormal signal; group II, focal atrophy or focal abnormal signal in the hippocampal formation; and group III, no significant volume reduction but an enlargement of the temporal horn. Results: All of the patients in group I had a history of status epilepticus in infancy. Temporal lobe epilepsy (TLE) was found in three of four patients. Group II contained TLE in three and frontal lobe epilepsy in one. One patient with intractable TLE had a history of status epilepticus in infancy. Group III contained miscellaneous epilepsies, including benign partial epilepsy with centro-temporal spikes in three of seven patients. Five patients in group III showed some characteristic features of hippocampal malrotation, which refers to incomplete hippocampal infolding. Conclusions: Diffuse and severe volume reduction of the hippocampal formation and anterior temporal lobe with unilateral hippocampal sclerosis was strongly associated with status epilepticus in infancy. Both hippocampal sclerosis and hippocampal malrotation suggest significant roles in the pathogenesis of epilepsy.

〔目的〕ダウン症候群（DS）の大脳皮質・白質の発達と加齢を抗Protein Gene Product 9.5（PGP9.5）抗体を用いて，免疫組織化学的に明らかにし神経の可塑性について考察した．〔対象〕DS群のヒト脳組織で大脳（前頭葉）24例（在胎19週から63歳）とした．〔方法〕抗PGP9.5抗体を用いて免疫組織化学的染色を行った．蛋白の発現を半定量的に判定し，脳病変のない正常発達群との比較検討を行った．〔結果〕DS群の乳幼児期大脳皮質では，第3・5層の錐体細胞層でPGP9.5の発現が減弱していたが，第2・4層の顆粒細胞層での発現は比較的正常発達群と類似していた．DS群青年期以降の大脳皮質の顆粒細胞層，錐体細胞層におけるPGP9.5陽性細胞は，正常発達群よりも増強していた．更に，DS群成人期では，アルツハイマー型病変の中にPGP9.5が強陽性を示す神経細胞が散在していた．〔結語〕DS群のPGP9.5陽性細胞の発現が正常発達群より減弱していることは，樹状突起やシナプスの発達遅滞を示唆し，顆粒細胞層での発現は，錐体細胞層の減弱に対する代償機能であると考えられた．学童期以降におこるPGP9.5の発現増強は，樹状突起の萎縮やスパインの減少に対する可塑性や神経細胞の活性化とも考えられた．DS群成人期では，神経細胞変性の一方で，残された正常細胞が再活性していることが示唆された．

Neuropathology and neuroimaging of long-term survival cases of arginase deficiency are rarely reported. The magnetic resonance imaging (MRI) of our case showed severe multicystic white matter lesions with cortical atrophy, which were more severe compared with previous reports. In this patient, low-protein diet successfully reduced hyperammonemia, but hyperargininemia persisted. These severe neurological and MRI findings may be explained by a compound heterozygote, inheriting both of severe mutant alleles from her parents.

To elucidate the neuropathological mechanism of Zellweger syndrome (ZS), we studied changes in the molecular species of glycerophospholipids in the cerebral tissue by thin-layer chromatography (TLC) and fast atom bombardment mass spectrometry (FABMS). First, we estimated the amount of plasmalogens by TLC. Plasmalogen-type phosphatidyl ethanolamine (PE) accounted for 30% of the total PE in the control brain, but was absent in the ZS brain. Plasmalogen-type phosphatidyl choline (PC) was undetectable in both control and ZS brains. Next, we analyzed plasmalogen-type PE by FABMS. Oleic (18:1), arachidonic (20:4) and docosapentanoic (22:5) acids were present in the control gray matter, but not in the ZS gray matter. In compensation for the defect of plasmalogen, the level of diacyl PE with polyunsaturated fatty acids, 20:4, 22:4, 22:5 and 22:6, was higher in the ZS brain than that in the control brain. These results indicate an alteration in the molecular species of PE, which may cause abnormal neural membrane fluidity and excessive vulnerability to oxygen stress.

〔目的〕発達期神経細胞に強く発現するPGP9.5抗体を用いて，PVL症例の大脳における発達を明らかにすることを目的とし，神経の可塑性と再生について考察した。〔対象〕慢性期PVLを認めた剖検ヒト脳組織15例（在胎24週から生後2歳1ヶ月）とした。〔方法〕PGP9.5抗体を用いて免疫組織化学的染色を行った。蛋白の発現を半定量的組織化学的に判定し，正常発達群との比較検討を行った。〔結果〕PGP9.5に対する免疫反応はPVLのタイプによって異なっていた。限局型における大脳皮質錐体細胞層ではPGP9.5陽性細胞は減弱していた。また，顆粒細胞層ではPGP9.5陽性細胞は増強していた。また，PVL病巣内部および周囲の大脳白質においてもPGP9.5免疫反応が増強して観察された。〔結論〕慢性期PVL症例における免疫反応増強は，損傷されたPVL病巣組織に代償する可塑性像と考えられた。

The lipid composition and molecular species of phospholipids were examined in the brain of a patient with Zellweger syndrome (ZS), and were compared with those of control infants. In the cerebral gray matter of the ZS patient, the amounts of ceramide monohexoside and cholesterol ester were larger than those of controls. By contrast, the amount of ceramide monohexoside in the white matter was smaller in the ZS patient than that in the age-matched control. Although the amount of phosphatidylcholine (PC) plus phosphatidylserine (PS) was the same, dipalmitoyl PC and PS were increased in both the gray and white matter of the ZS cerebrum. These alterations in the molecular species of brain lipids may play crucial roles in the pathogenesis of ZS.

Nestin is a cytoskeletal protein expressed by neural stem cells, and by immature neurons and glial cells. In an effort to explore the potential of the infant brain for repair and plasticity, we immunohistochemically studied nestin expression in the human cerebral cortex of control subjects and of patients with periventricular leukomalacia. During normal development, nestin immunoreactivity of the cortical gray and white matter was detectable throughout the fetal period, and disappeared around birth. In brain with periventricular leukomalacia, nestin expression was altered in a time- and space-dependent manner. In the cortical gray matter, neuronal immunoreactivity was often reduced in the subacute stage, but was increased in chronic and remote stages. In the white matter near a lesion of periventricular leukomalacia, glial immunoreactivity was increased in all stages. In many cases, neurons and axons far from a lesion also showed an altered expression of nestin. These findings indicate that in brain with periventricular leukomalacia, neurons and glial cells may recapitulate nestin expression in response to ischemic brain injury, suggesting functional relevance in repair and plasticity.

大脳皮質の発達期には神経細胞の胞体が各領域で産生，分化した後，放射方向と接線方向に移動し層構造を形成するとされている。ヒト大脳皮質発達期の神経細胞に特異的なタンパク質として発見されたPGP9.5（ユビキチンカルボキシル末端酵素）が発現する状況を免疫組織化学的に検討した。ヒトの発達期におけるPGP9.5の発現は，在胎13週には分子層外部のCajal-Retzius細胞に，その後5層錐体細胞，2・4層顆粒細胞，3層錐体細胞の胞体，ニューロピルの順で増強し，加齢により低下していた。大脳白質では深層部が分子層外部と同時期に増強し加齢により低下していた。PGP9.5による陽性細胞の発現は，ヒト大脳皮質の正常な発達に沿って増強しており，軸索および樹状突起の成長発達を反映するものと考える。さらに神経系の損傷後には神経幹細胞が出現し再度軸索および樹状突起が成長発達を示すことから，神経系の損傷後に再生する蛋白質として軸索および樹状突起再生の指標となると考えられた。

Mutations of genes encoding GABA(A) receptor alpha 1 (GABARA1) and gamma 2 subunit (GABARG2) are associated with age-dependent epilepsy. The development of the subunits expression may be related to the age-dependency of epilepsy. Nevertheless, developmental and spatial changes in expression of GABA(A) receptors have not been examined in the human brain. Using immunohistochemistry, we examined the development of GABARA1 and GABARG2 in the human temporal lobe, hippocampus and basal ganglia in specimens obtained from 21 fetuses/subjects who died aged 22 gestation weeks (GW) to 75 years. Unique developmental changes of GABARA1 and GABARG2 were recorded in each region. In hippocampal pyramidal cells, GABARA1 was already found from 22 GW mainly on CA2-3, whereas GABARG2 was expressed later than GABARA1 predominantly in CA3. In the temporal cortex, both subunits appeared in the pyramidal cells layer from 22 GW, while GABARA1 and GABARG2 expression was increased from 29 to 38 GW, respectively. Furthermore, transient increase of GABARA1 was detected in the granular cell layer of the hippocampus from 29 GW to 4 months, in the cortical pyramidal cell layer from 29 to 40 GW, and in the putamen from birth to 5 years of age. Thus gradual or transient increase of GABARA1 and GABARG2 was found in every region at different age. These developmental changes in the expression of these subunits may contribute to the age dependency in some epilepsy syndromes where deficiency of GABARA1 and GABARG2 is involved.

Video game playing is an attractive form of entertainment among school-age children. Although this activity reportedly has many adverse effects on child development, these effects remain controversial. To investigate the effect of video game playing on regional cerebral blood volume, we measured cerebral hemoglobin concentrations using near-infrared spectroscopy in 12 normal volunteers consisting of six children and six adults. A Hitachi Optical Topography system was used to measure hemoglobin changes. For all subjects, the video game Donkey Kong was played on a Game Boy device. After spectroscopic probes were positioned on the scalp near the target brain regions, the participants were asked to play the game for nine periods of 15s each, with 15-s rest intervals between these task periods. Significant increases in bilateral prefrontal total-hemoglobin concentrations were observed in four of the adults during video game playing. On the other hand, significant decreases in bilateral prefrontal total-hemoglobin concentrations were seen in two of the children. A significant positive correlation between mean oxy-hemoglobin changes in the prefrontal region and those in the bilateral motor cortex area was seen in adults. Playing video games gave rise to dynamic changes in cerebral blood volume in both age groups, while the difference in the prefrontal oxygenation patterns suggested an age-dependent utilization of different neural circuits during video game tasks.

Perinatal hypoxic-ischemic brain damage is a major cause of neuronal and behavior deficits, in which the onset of injury can be before, at or after birth, and the effects may be delayed. Pontosubicular neuron necrosis (PSN) is one of perinatal hypoxic-ischemic brain injury and its pathological peculiarity is neuronal apoptosis. In this study, we investigated whether apoptotic cascade of PSN used a caspase-pathway or not, and whether hypoglycemia activated apoptosis or not. Sections of the pons of PSN with and without hypoglycemia were stained using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) and immunohistochemistry for glial fibrillary acidic protein (GFAP), Bcl-2, Bcl-x and activated caspase 3. Additionally, we performed immunoblot analysis of Bcl-2, Bcl-x and activated caspase 3. TUNEL-positive cell was closely associated with the presence of karyorrhexis. Under combination of karyorrhectic and TUNEL-positive cells, number of apoptotic cells in premature brains was significantly more than in mature brains. Hypoxic-ischemic brain injury was considered to easily lead to apoptosis in premature infants. Moreover, as this pathophysiology, caspase-pathway activation contributed to neuronal death from caspase-immunoexpression analyses. PSN with hypoglycemia showed large number of apoptotic cells and higher expression of activated caspase 3. The result may be more severe with the background of hypoglycemia and prematurity complicated by hypoxia and/or ischemia.

Methylmalonic acidemia is a rare disease, and its neuropathology in childhood has been rarely reported. A 3-year-old male with vitamin B12 nonresponsive type of methylmalonic acidemia developed repeated attacks of acidemia associated with common cold since neonatal age. Psychomotor development was markedly delayed, and he died of a severe attack of acidemia. Postmortem examination disclosed marked brain atrophy with old lesions of hypomyelination, granule cell reduction, and spongy changes scattered in the cerebral cortex, white matter, brainstem nuclei, and cerebellar cortex, and accompanied by recent lesions of multiple small hemorrhagic and necrotic foci in the caudate nucleus, cerebellum, and brainstem. Neuron reduction without astrogliosis in the cerebellum, brainstem, and hippocampus, and the association of single-stranded DNA-positive cells in the brainstem and cerebellar nuclei were demonstrated. These findings, and karyorrhexis in the neonatal brains described in the literature, suggest that repeated episodes of cell death with apoptosis occur in association with attacks of acidosis beginning in the neonatal period in methylmalonic acidemia.

Down’s syndrome (DS) is characterized by intellectual disabilities and Alzheimer-type dementia. Cystathionine-β synthase (CBS) plays a role in the production of hydrogen sulfide (H2S) in the brain and is encoded by a gene which is localized in the DS critical region of chromosome 21. The expression of CBS was compared during development and aging. Therefore, cerebri (temporal lobe) and cerebelli from fetuses and adults were studied in 22 normal controls and 21 DS patients using immunohistochemical methods. During normal development, CBS-positive astrocytes appeared in the cortical layer at 14 weeks of gestation (GW), remained elevated until 34 GW and decreased slightly during the infantile period (1–11 months of age). A few CBS-positive neurons were transiently found in the deep cortical layer only at 35 GW. In the cerebellum, CBS-positive Bergmann glial cells were found from 26 GW to adulthood in both controls and DS patients. In DS, there were greater numbers of CBS-positive astrocytes, situated predominantly in granular cell layers II and IV, compared to the controls. In addition, CBS-positive astrocytes were also increased around senile plaques in adults with DS. The high level of CBS in the granular cell layers in DS may be related to an abnormal development of inhibitory neurons and may be responsible for the pathogenesis of intellectual disability, while the increased CBS observed in adult DS may be related to the pathogenesis of Alzheimer-type dementia.

Background : Substance P (SP) is a neuropeptide transmitter found in sensory neurons of the central nervous system and related to pain sensation and respiratory regulation. Some reports claim an increase in SP in the brains of SIDS victims, so the correlation between SP and sleep apnea was investigated here. Materials and methods : Among 27,000 infants studied prospectively to characterize their sleep–wake behavior, 38 infants died under 6 months of age, which included 26 cases of Sudden Infant Death Syndrome (SIDS). All the infants had been recorded during one night in a pediatric sleep laboratory some 3 to 12 weeks before death. The frequency and duration of sleep apnea were analyzed. Brainstem material was collected and immunohistochemistry for SP was carried out. The density of SP positive fibers was measured in the nucleus spinal and mesencephalic nervi trigemini and nucleus parabranchialis in the brainstem of abovementioned cases. Correlation analyses were carried out between the density of SP and the data of sleep apnea. Results : There was no SIDS specific correlation of SP through the above-listed parts of the midbrain with frequency and duration of sleep apnea. Conclusions : There was no significant association between the SP findings and apnea data in SIDS; this is not in agreement with the association of apnea in pathophysiology of SIDS.

Background : The sudden infant death syndrome (SIDS) is still the main cause of postneonatal infant death. However, the causes and mechanisms of SIDS have never been completely elucidated. Catecholamines, via α2-adrenergic receptor (α2-AR) interactions, are known to influence brainstem autonomic and respiratory activity. Aims : To examine the catecholaminergic system abnormalities in SIDS victims, we investigated the alterations of α2-AR subtypes. Subjects and methods : We examined the developmental changes of α2-AR subtypes in the brainstem, especially in cardiorespiratory nuclei, in 21 SIDS victims and 17 age-matched controls by means of immunohistochemical methods. For statistical analysis, the χ 2 -test or Fisher's exact probability test was performed. Results : There was a significant decrease in α2A-AR immunoreactivity in the solitary nucleus and ventrolateral medulla (VLM) in the medulla oblongata in SIDS victims compared with in control cases, but there were no significant differences of the α2B and α2C-AR immunoreactivity in the brainstem between SIDS victims and controls. Conclusion : α2A-AR immunoreactivity was selectively decreased in the solitary nucleus and VLM in the medulla oblongata in SIDS victims, so there was no possibility that it was secondary to chronic hypoxia or repeated ischemia. It may be related to some impairment of the cardiorespiratory neuronal system. Therefore, SIDS victims may be vulnerable to asphyxia, hypoxia, and/or hypercapnia, and fail to exhibit brainstem responses.

Perinatal pontosubicular neuron necrosis (PSN) has similar characteristics to apoptosis, such as karyorrhexis, cellular atrophy and little glial reaction. In PSN pathogenesis, the developmental discrepancy between neurons exhibiting late maturation and vessels showing an early increase in the basis pontis and subiculum may predispose fetuses and neonates to PSN. Ischemia, hyperoxygenemia, hypocarbia and hypoglycemia have been reported to be causal factors. Apoptotic neurons are associated with activation of caspase-3, and remaining neurons are accompanied by growth factors in glial cells. Nestin, which is abundant in multipotential stem cells, is reactivated in cells surrounding the subacute and chronic lesions. Thus, local plasticity may be activated both in necrotic and apoptotic cell death, and the period of regeneration is important for the treatment of PSN.

The Eker rat is an animal model of tuberous sclerosis caused by a mutation in the Tsc2 gene encoding a tumor suppressor protein, tuberin. According to Knudson's two-hit theory, renal carcinomas and other tumors develop in various organs. Although the incidence of brain lesions is lower in the Eker rat than in human tuberous sclerosis, a cortical tuber was recently found in the cerebrum of an Eker carrier. In this study, we examined whether neuronal cytomegaly in the Eker rat tuber is caused by deletion of the normal Tsc2 allele and resultant loss of tuberin, as is the case with the majority of renal carcinomas. A combination of laser capture microdissection and semi-nested polymerase chain reaction demonstrated the presence of the wild-type Tsc2 allele in the cytomegalic neurons isolated individually. Immunohistochemistry also detected positive tuberin immunoreactivity in many of these giant neurons. These findings were in sharp contrast to those of renal carcinoma cells deriving from allelic loss. Our results provide evidence that many if not all cytomegalic neurons of a cortical tuber occur in the absence of allelic loss.

We immunohistochemically studied the expression of beta-amyloid precursor protein (APP), Abeta40, Abeta42, and Abeta43 in the frontal lobes of 20 Down syndrome (DS) patients and 13 controls. The immunoreactivity for each antibody was different in the degree of intensity and the chronological pattern of expression. APP and Abeta43 immunoreactivity was increased in neurons initially, and then Abeta43 and 42 immunoreactivity appeared in diffuse plaques from 32 years of age. APP and Abeta43 were characteristically observed in axons around senile plaques. Finally, Abeta40 immunoreactivity was detected in the cores of senile plaques. This time course of immunoreactive expression may be related to the pathogenetic process of Alzheimer-type dementia in DS, and the axonal damage in senile plaques may lead to the formation of neurofibrillary tangles (NFT) or neuronal death through axonal flow disturbance and accumulation of Abeta43 in cortical neurons.

During influenza epidemics in Japan, the number of children with acute encephalopathies and encephalitis has recently increased. Although the pathophysiologies remain unclear, there is usually brain edema with evidence of damage to the blood-brain-barrier (BBB). We investigated the glial reaction and apoptosis in brains of eight such cases comprising two of acute necrotizing encephalopathy and six of influenza encephalopathy, and compared the results with those in five control brains. Apoptosis, evidenced by chromatin condensation and fragmentation in hematoxylin sections, in situ end labeling of fragmented DNA (TUNEL) and DNA laddering, was observed in neurons and glial cells in four brains with influenza encephalopathy. In the TUNEL-positive brains, the increase in microglia was greater than in the TUNEL-negative brains. Immunoreactivity for active-caspase 3, demonstrated by immunohistochemistry, and the overexpression of a caspase-cleaved fragment of poly(ADP-ribose) polymerase, demonstrated by Western blotting, indicated that activation of caspase 3 is involved in the apoptotic pathway in the brains of influenza encephalopathy cases. Apoptosis or specific pathological processes that cause apoptosis may give rise to aggravated encephalopathy.

Myelin transcription factor 1 (MyT1) is a zinc-dependent, DNA-binding protein, and is known to be expressed in early progenitors of oligodendrocytes. We examined the immunoreactivity of MyT1 in developing human brains and brains with periventricular leukomalacia (PVL) to understand the relationship between the expression of MyT1 and myelination in PVL brains. MyT1-positive glial cells were first detected at 19 gestational weeks (GWs) and then gradually increased until 26-29 GWs in the control group. Then they decreased and became very rare at 1 year of age. The expression of MyT1 immunoreactivity shifted from the nucleus to the cytoplasm of the glial cells in the developmental time course. In the chronic stage of PVL, MyT1-positive cells were significantly increased around necrotic foci and some of the regions were coincident with increasing MBP and PLP immunoreactivity. These results may reflect myelin repair on dysmyelination around PVL areas. Therefore, MyT1 may play an important role in the myelin repair in PVL regions.

Cerebral cortical lesions of tuberous sclerosis (TSC) and focal cortical dysplasia (FCD) show disturbances in laminar architecture and cellular differentiation. We immunohistochemically studied the expression of doublecortin, a fetal neuronal protein that regulates neuronal migration, in the surgical specimens of five TSC and eight FCD patients. In both TSC and FCD, bizarre giant cells showed a variable degree of doublecortin immunoreactivity. Both cytomegalic neurons and balloon cells were positive. The staining tended to be more intense in TSC than in FCD, although there were exceptional cases in both groups. Doublecortin immunoreactivity of normal-sized neural cells was restricted to a small number of astrocytes, and comparable to that in control patients. The persistent expression of doublecortin by giant cells in the postnatal cerebrum is additional evidence of abnormal differentiation, which may be relevant to the pathogenesis of cortical disarray in TSC and FCD.

Background: We investigated the hypothesis that sodium nitroprusside (SNP), a nitric oxide (NO) donor, increased the cerebral blood flow and oxygenation during kainic acid (KA)-induced seizures in newborn rabbits. Methods: After KA administration (i.v. 12 mg/kg) to induce seizures, either 1.2 mg/kg SNP (SNP group, i.v., n = 6) or 1 mL normal saline (vehicle group, i.v., n = 6) was given. Regional cerebral blood flow (rCBF), cerebral oxyhemoglobin (oxy-Hb), deoxyhemoglobin (deoxy-Hb), total hemoglobin (t-Hb), mean arterial blood pressure (MABP), heart rate (HR) and electroencephalography (EEG) were continuously monitored throughout the experiment, lasting at least 60 min after the KA administration. Results: The value for rCBF was greatly increased during seizures in the SNP group than in the vehicle group. The values for oxy-Hb and t-Hb were significantly increased, and deoxy-Hb was significantly decreased. There were ameliorations of cerebral oxygenation in the SNP group during the acute phase of seizures in the neonatal animals, compared with the vehicle group. There were no significant differences in the MABP, HR, arterial blood gases, rectal and brain temperatures, blood hemoglobin concentrations, blood glucose levels, the latencies to first abnormal discharges in EEG, the total sum of the duration of abnormal discharges in EEG and the incidences of subclinical electric status epileptics between the two groups. Conclusions: These results suggest that the treatment with SNP contributed to the increases in cerebral blood flow and oxygenation, and that EEG abnormalities were unchanged by the treatment with SNP during neonatal seizures.

Infection with Shiga toxin (Stx)-producing Escherichia coli O157:H7, which causes diarrhea and hemorrhagic colitis in humans, often results in fatal systemic complications, such as neurological damage and hemolytic–uremic syndrome. Because Stx circulating in the blood is a major causative factor of these complications, the development of a Stx neutralizer that functions in the circulation holds promise as a viable therapy. Here we developed a series of carbosilane dendrimers, in which trisaccharides of globotriaosyl ceramide, a receptor for Stx, were variously oriented at their termini (referred to as SUPER TWIG), and identified a SUPER TWIG with six trisaccharides as a Stx neutralizer functioning in the circulation. This SUPER TWIG specifically bound to Stx with high affinity ( K d = 1.1 × 10 −6 M) and inhibited the incorporation of the toxin into target cells. Intravenous administration of the SUPER TWIG along with Stx to mice substantially reduced the fatal brain damage and completely suppressed the lethal effect of Stx. Moreover, the SUPER TWIG protected mice from challenge with a fatal dose of E. coli O157:H7, even when administered after the establishment of the infection. The SUPER TWIG neutralized Stx in vivo by a mechanism in which the accumulation and immediate degradation of Stx by phagocytic macrophages present in the reticuloendothelial system were induced. Taken together, our findings indicate that this SUPER TWIG is therapeutic agent against infections by Stx-producing E. coli .

Four-hydroxynonenal (HNE) has been proposed as an important marker of radical-induced lipid peroxidation. The principal objective of this study was to assess the occurrence of lipid peroxidation in normal perinatal brain and brains with one form of pontosubicular neuronal necrosis (PSN). Immunochemical studies using an antibody against HNE-modified protein were performed in controls aged from 20 weeks of gestation to 64 years, and patients with PSN. Immunohistochemical study showed developmental and aging changes of positive staining in Purkinje cells and pontine neurons (27 weeks-7 months, 50 and 64 years). In addition, karyorrhectic cells in pontine nuclei with PSN were positively stained. Immunoblotting revealed that a 75-kDa protein, which is speculated to be mitochondrial complex-1 protein, was the most intensely expressed among multiple immunoreactive proteins. Our results identified the presence of oxidative stress in the perinatal neuron, and this oxidative stress may contribute to some forms of karyorrhectic death.

The functional organization of the developing human brain does not only differ substantially from that of the mature brain, but it also undergoes continuous changes. During fetal brain development, transient neuronal circuitries are formed which are essential for the subsequent development of mature projections. Transitory connections are linked to transient structures which are particularly prominent in the human fetal brain and are susceptible to damage under pathological circumstances. The First International Symposium on Normal and Abnormal Development of the Human Fetal Brain aimed to gather basic information on these transitory organizations and the major developmental events that occur in the fetal brain. This paper summarizes a roundtable discussion at the symposium on transient characteristics and injuries in the developing human cerebral cortex. An overview of cortical development is first presented and then the development of several fetal structures, including the subventricular zone, ganglionic eminence, marginal zone, subplate and cortical plate, is discussed with regard to their important contribution to the formation of the correct fiber projections in the adult. The last section focuses on the anomalies that are commonly found in the premature fetal brain on the one hand and on the other hand are related to the transitory characteristics of the developing brain.

Periventricular leukomalacia (PVL) in prematurely born infants is an important cause of cerebral palsy and intellectual impairment. In the pathogenesis of PVL, both the developing vasculature and differentiating glial progenitor cells within the deep white matter are susceptible to ischemia and very important as predisposing factors. Axonal swellings, which occur as the first signs of PVL, are found in fetuses as well as neonates, and cellular activation secondary to intrauterine infection may also predispose to PVL. Causal factors include cerebral hypoperfusion in the perinatal period, which leads to axonal damage, glutamate release, elevated production of cytokines in microglia and nerve growth factor in astrocytes, and finally an increased plasticity in neurons and oligodendrocytes. Cellular reactivities such as nestin expression following PVL may represent important indicators for determining the effective time for treatment and rehabilitation.

Background Severe motor and intellectual disability (SMID) patients cannot express their feelings with language. Understanding what they are thinking about or how they feel is thus difficult. This study focused on brain responses to hearing their own names to clarify the situation in these patients. Methods We performed and analyzed electroencephalography (EEG) for six patients with SMID and eleven healthy subjects. All subjects were presented with auditory stimuli including calling the subject’s own name (SON) and reading words. EEG was analyzed by time–frequency analysis, event-related spectral perturbation (ERSP) to detect EEG power changes caused by EEG amplitude, and inter-trial coherence (ITC) to investigate phase-locked changes. Results ERSP results from healthy subjects showed significant theta power increases as a specific response to SON. While we could not identify a similar pattern in the responses of patients with SMID, analysis of ITC revealed that theta phase-locked activity increased in response to SON not only in all healthy subjects, but also in four patients. Discussion These results indicate that theta phase-locked activity in some patients with SMID was strongly associated with SON, as in healthy subjects. Our study suggests the existence of specific neural markers that signal an attentional shift in patients upon hearing SON.

We immunohistochemically examined neurotransmitter systems, which function in the brainstem and are involved in neuronal organization of respiration, in an autopsy brain from a patient with Rett syndrome (RS). Immunoreactivity (IR) for tyrosine hydroxylase, a functional marker for catecholaminergic neurons, was severely reduced in the locus ceruleus, while that for tryptophan hydroxylase involved in serotonin synthesis was spared in the raphe nuclei. In the brainstem, IR for substance P (SP) was reduced in the parabrachial complex and that for methionine-enkephalin (met-enk) was affected in the parabrachial, hypoglossal, dorsal vagal and solitary nuclei. In addition, expressions of these neuropeptides were also disturbed in the basal ganglia. A widespread altered expression of antagonistic neuropeptides, SP and met-enk, may be involved in the pathogenesis of RS, especially in its respiratory manifestation.

We examined the effects of 7-nitroindazole (7-NI) and N-ω-nitro- l -arginine methyl ester ( l -NAME) on the endogenous nitric oxide (NO) production in vivo, cerebral hemodynamics, and hippocampal lesions to investigate the different roles between endothelial NOS (eNOS) and neuronal NOS (nNOS) during kainic acid (KA)-induced seizures in newborn rabbits. After a pre-treatment with 7-NI (50 mg/kg, i.p.), l -NAME (20 mg/kg, i.v.) or saline (1 ml, i.v.), KA (12 mg/kg, i.v.) was administered. NO production in the brain, regional cerebral blood flow (rCBF), cerebral oxygenation (concentrations of oxyhemoglobin (HbO2), deoxyhemoglobin (HbR), and total hemoglobin (tHb) in the brain tissue), and electroencephalography (EEG) were continuously monitored throughout the experiment lasting at least 60 min after the KA administration. There was a significant increase in NO generation in the brain during KA-induced seizures, which was inhibited by a pre-treatment with 7-NI or l -NAME. KA-induced seizures also increased rCBF significantly, which was inhibited not by 7-NI but by l -NAME. l -NAME pre-treatment caused a significant decrease in HbO2 and a significant increase in HbR during KA-induced seizures, compared with 7-NI and saline pre-treatment. EEG abnormalities and Neuronal damages in the hippocampus were significantly lower in 7-NI- and l -NAME-treated animals respectively, than in saline-treated animals. The present data demonstrated that the selective nNOS inhibitor, 7-NI, attenuated neither rCBF nor cerebral oxygenation during the seizures, while the non-selective NOS (nNOS and eNOS) inhibitor, l -NAME, attenuated both. These findings suggest that NO, probably originating from eNOS, may play an important role in the cerebral circulation. Both 7-NI and l -NAME inhibited the NO production and EEG abnormalities during the seizures that led to less damage to the hippocampus.

Acute encephalopathy associated with Shiga toxin-producing Escherichia coli (STEC) primarily affects children. To elucidate the age-dependent vulnerability of the central nervous system (CNS), we injected Shiga toxin 2 (Stx2) intravenously to young rabbits and examined the clinical and pathological effects on the CNS. Although neurological disorders caused by Stx2 were similar between young and adult rabbits, the dose required to produce them in the young was one third of that required for the adults. Vascular lesions appeared as early as 24 h after injection in the young, but not at all in the adult. Arteriolar changes, such as hydropic swelling of the endothelial cells and karyorrhexis of the medial cells, were specific to the CNS of young animals. Evidence for apoptosis of vascular cells was scarce because DNA strand breaks and activation of caspases-3 and -9 were absent in the vast majority. Given our results, we conclude that the cerebral blood vessels of immature brains are more vulnerable to Stx2 than those of adults in the rabbit.