Neuroradiological and neurofunctional examinations for the patients with 22q11.2 deletion

Since neuroradiological features of patients with 22q11.2 deletion syndrome are not well-understood, examinations using functional imaging were performed in this study. Brain magnetic resonance imaging(MRI) and 1H-magnetic resonance spectroscopy(MRS) were performed using a clinical 3-tesla MR imager in 4 patients with 22q11.2 deletion syndrome (2 boys and 2 girls; 2~6 years.) and 20 age- and sex-matched healthy control subjects. Furthermore, interictal 123I- iomazenil (IMZ) single photon emission computed tomography(SPECT) was examined in two of the four patients. Among 4 patients with 22q11.2 deletion syndrome, 2 patients showed polymicrogyria and 1 patient showed agyria. Those patients with brain malformations also showed abnormal brain artery and decreased accumulation of IMZ in 123I-IMZ SPECT. Although all 4 patients showed epileptic discharges in electroencephalogram(EEG), one patient with polymicrogyria had no seizure episode. Decreases in γ-aminobutyric acid(GABA) corresponding to the areas of polymicrogyria and/or epileptic discharges in EEG were shown in all patients except for the patient with agyria. Although consistent evidence was not seen in patients with 22q11.2 deletion syndrome in this study, brain malformations and disturbances of the GABAergic nervous system would be underlying mechanisms of the neurodevelopmental abnormalities in this syndrome

ジヘイショウ ノ シンダン チリョウ サイゼンセン

In this paper we review the pathophysiology of autism.1）The amygdala theory of autismThe network of neural regions that comprise the social brain includes the amygdala. There isa reduction in volume of amygdala in children with autism. The concentration of N-acetylaspartateis also decreased in amygdala of autistic brain. The amygdala is therefore proposed to be one ofseveral neural regions that are abnormal in autism.2）Mirror neuron dysfunction in autismChildren with autism underwent fMRI while imitating and observing emotional expressions.They showed no mirror neuron activity in the inferior frontal gyrus（pars opercularis）. Notably,activity in this area was inversely related to symptom severity in the social domain, suggestingthat a dysfunctional mirror neuron system may underlie the social deficits observed in autism

Low Temperature Properties of Quantum Antiferromagnetic Chains with Alternating Spins S=1 and 1/2

We study the low-temperature properties of S=1 and 1/2 alternating spin chains with antiferromagnetic nearest-neighbor exchange couplings using analytical techniques as well as a quantum Monte Carlo method. The spin-wave approach predicts two different low-lying excitations, which are gapped and gapless, respectively. The structure of low-lying levels is also discussed by perturbation theory in the strength of the Ising anisotropy. These analytical findings are compared with the results of quantum Monte Carlo calculations and it turns out that spin-wave theory well describes the present system. We conclude that the quantum ferrimagnetic chain exhibits both ferromagnetic and antiferromagnetic aspects.Comment: 13 pages, RevTeX, six figures, submitted to J. Phys. Cond. Ma

Identification of a novel motif responsible for the distinctive transforming activity of human T-cell leukemia virus (HTLV) type 1 Tax1 protein from HTLV-2 Tax2

<p>Abstract</p> <p>Background</p> <p>Human T-cell leukemia virus type 1 (HTLV-1) is a causative agent of adult T-cell leukemia (ATL), whereas its relative HTLV-2 is not associated with any malignancies including ATL. HTLV-1 Tax1 transformed a T-cell line from interleukin (IL)-2-dependent growth to IL-2-independent growth, with an activity that was much more potent in comparison to HTLV-2 Tax2. This distinction was mediated by at least two Tax1 specific functions, an interaction with host cellular factors through the PDZ domain binding motif (PBM) and the activation of NF-kappaB2 (NF-κB2)/p100.</p> <p>Results</p> <p>Using a series of Tax1 chimeric proteins with Tax2, we found that amino acids 225-232 of Tax1, the Tax1(225-232) region, was essential for the activation of NF-κB2 as well as for the high transforming activity. The strict amino acid conservation of Tax1(225-232) among HTLV-1 and simian T-cell leukemia virus type 1 (STLV-1), but not HTLV-2 and STLV-2, indicates that function(s) through the Tax1(225-232) region are biologically significant. Interestingly, another HTLV-1 relative, HTLV-3, has a PBM, but does not conserve the Tax1(225-232) motif in Tax3, thus indicating that these two motifs classify the three HTLVs into the separate groups.</p> <p>Conclusion</p> <p>These results suggest that the combinatory functions through Tax1(225-232) and PBM play crucial roles in the distinct biological properties of the three HTLVs, perhaps also including their pathogenesis.</p

Evaluation of the GABAergic nervous system in autistic brain : 123I-iomazenil SPECT study

Purpose: To evaluate the GABAA receptor in the autistic brain, we performed 123I-IMZ SPECT in patients with ASD. We compared 123I-IMZ SPECT abnormalities in patients who showed intellectual disturbance or focal epileptic discharge on EEG to those in patients without such findings. Subjects and methods: The subjects consisted of 24 patients with ASD (mean age, 7.3±3.5years), including 9 with autistic disorder (mean age, 7.0±3.7years) and 15 with Asperger’s disorder (mean age, 7.5±3.2years). We used 10 non-symptomatic partial epilepsy patients (mean age, 7.8±3.6years) without intellectual delay as a control group. For an objective evaluation of the 123I-IMZ SPECT results, we performed an SEE (Stereotactic Extraction Estimation) analysis to describe the decrease in accumulation in each brain lobule numerically. Results In the comparison of the ASD group and the control group, there was a dramatic decrease in the accumulation of 123I-IMZ in the superior and medial frontal cortex. In the group with intellectual impairment and focal epileptic discharge on EEG, the decrease in accumulation in the superior and medial frontal cortex was greater than that in the group without these findings. Conclusion The present results suggest that disturbance of the GABAergic nervous system may contribute to the pathophysiology and aggravation of ASD, since the accumulation of 123I-IMZ was decreased in the superior and medial frontal cortex, which is considered to be associated with inference of the thoughts, feelings, and intentions of others (Theory of Mind)

Dating of the Dome Fuji, Antarctica deep ice core (scientific paper)

The Antarctic ice sheet preserves paleo-climate information in the form of physical and chemical stratigraphy. A deep ice core was continuously drilled down to a depth of 2,503 m at Dome Fuji station, East Dronning Maud Land, Antarctica, during the 1993-97 JARE inland operations. Oxygen isotope measurements were conducted on 7 to 50 cm-long ice core samples selected from the entire core depth. A time scale for the Dome Fuji core is calculated from past accumulation rates and an ice flow model. Past accumulation rates were converted from oxygen isotope values by using an empirical equation obtained in the Dome Fuji area. A steady-state flow model was preciously developed for a time scale calculation of the Summit ice core, Greenland. Using reference depth points from volcanic signals and annual layer thickness values measured on the Dome Fuji core allows for tuning of the calculated time scale. A depth-age profile was obtained for the past 320 kyr. The obtained paleo-temperature profile shows the characteristics of the past three glacial and interglacial periods. The power spectrum of &#402;&Acirc;18O change over an interval of 320 kyr reveals three dominant cycles. The paleo-temperature profile coincides quite well with the Vostok ice core data in general but not in detail, suggesting that further studies are needed both for chronological investigations and a multi-factor, cross-correlation analysis between deep ice cores for climatological understanding

Clinical Evaluation and Metabolism of Sevoflurane in Patients

Sevoflurane was submitted to Phase II studies in patients following Phase I studies. Sevoflurane, 2% inspired during maintenance, was administered with 50% N2O in oxygen to produce surgical anesthesia in 9 orthopedic patients of ASA Physical Status I. Under controlled ventilation, endotracheal concentration of sevoflurane was recorded. The blood concentration of sevoflurane was measured during and after the inhalation. Serum, urinary inorganic fluoride, and glucuronide of hexafluoroisopropanol were analysed with ion chromatographic analyzer. The patient inhaled sevoflurane for 3.5 ± 1.6 hr. All the patients were anesthetized and operated uneventfully. Postoperative laboratory findings showed no unexplainable abnormality. The end expiratory concentration of sevoflurane reached a plateau in 4.0 ± 0.8 min and fell rapidly after discontinuation of sevoflurane. Blood concentration of sevoflurane was about 500 μM during inhalation. It decreased promptly after termination of sevoflurane and was not correlated with anesthetic time. The time for verbal response after discontinuation was 11.8 ± 4.2 min. The serum concentration of inorganic fluoride increased after inhalation and reached a plateau (13.7 ± 8.2 μM) in 120 min. The level lasted for 120 min after anesthesia and fell by half at 12 hr after anesthesia. Urinary fluoride concentration varied from 20 to 3,000 μM during the first 12 hr urine, and showed its maximum in the first postoperative 12 or 24 hr urine. The findings that sevoflurane with nitrous oxide and oxygen produced surgical anesthesia without any sequelae and that the serum fluoride level did not exceed the nephrotoxic level warrent the further clinical evaluation in a wider range of subjects.A part of this work was supported by a Research Grant from the Japanese Ministry of Education, Science and Culture and presented at the 8th European Congress of Anaesthesiology, Vienna, Austria, in September, 1986

Estimation of annual layer thickness from stratigraphical analysis of Dome Fuji deep ice core

Dating of ice cores is of important but is difficult for an ice core where there is low snow accumulation, and also for the deep part because seasonal chemical and isotopic signals are not easily preserved due to vapor migration after snow deposition and molecular diffusion in the deep part of ice sheet. In this paper, an attempt to reveal annual layer thickness is conducted on the basis of precise number density measurement of air bubbles and air hydrates. The annual layer thickness from air bubbles and hydrates agrees well with a calculated value within 10-15% at all depths of the 2500 m deep core. The obtained thickness in the interglacial period according to Eemian period in the Greenland ice core was half of the calculated value

Enhanced Autophagy and Reduced Expression of Cathepsin D Are Related to Autophagic Cell Death in Epstein-Barr Virus-Associated Nasal Natural Killer/T-Cell Lymphomas: An Immunohistochemical Analysis of Beclin-1, LC3, Mitochondria (AE-1), and Cathepsin D in Nasopharyngeal Lymphomas

This study investigated autophagy in 37 cases of nasopharyngeal lymphomas including 23 nasal natural killer (NK)/T-cell lymphomas (NKTCL), 3 cytotoxic T-cell lymphomas (cytotoxic-TML) and 9 B-cell lymphomas (BML) by means of antigen-retrieval immunohistochemistry of beclin-1, LC3, mitochondria (AE-1) and cathepsin D. Peculiar necrosis was noted in EBV+ lymphomas comprising 21 NKTCL, 2 cytotoxic-TML and 1 BML. Lymphomas without peculiar necrosis showed high expression of beclin-1, macrogranular cytoplasmal stain of LC3 with sporadic nuclear stain, a hallmark of autophagic cell death (ACD), some aggregated mitochondria and high expression of cathepsin D, suggesting a state of growth with enhanced autophagy with sporadic ACD. EBV+ NKTCL with the peculiar necrosis, showed significantly low level of macrogranular staining of LC3, aggregated mitochondria and low expression of cathepsin D in the cellular areas when degenerative lymphoma cells showed decreased beclin-1, significantly advanced LC3-labeled autophagy, residual aggregated mitochondria and significantly reduced expression of cathepsin D, suggesting advanced autophagy with regional ACD. Consequently it was suggested that enhanced autophagy and reduced expression of lysosomal enzymes induced regional ACD under EBV infection in NKTCL