Search PubMed⌕ Search

Biomedical subjects

M Tayama

Publications and source records attributed to M Tayama.

At least 37 records · Page 2Linked to original sources
PubMed1993

Moebius syndrome: continuous tachypnea verified by a polygraphic study.

Four polygraphic recordings were obtained in three cases of Moebius syndrome. The cases were a 4-month-old girl (Case 1), a 4-year-old boy (Case 2), and a 5-year-old girl (Case 3). The recordings revealed that in all three cases there was a lack of rapid eye movements to the lateral side, continuous low amplitude on chin EMG, and continuous tachypnea. In Case 3, polygrams were recorded at 2 and 5 years of age, both records showing the same pattern of tachypnea. Arterial blood gas analysis (AGA), PH, PaCO2 and PaO2 were found to be within normal limits. It has been assumed that this syndrome includes brainstem dysplasia, according to the chief symptoms, and autopsy and auditory brainstem response (ABR) findings. ABR examination showed low amplitude of waves, a prolonged wave I-V interval, and the absence of wave V. It is known that there is a close relationship between this syndrome and respiratory disorders. But there have only been a few reports on respiratory disorders in this syndrome. It is strongly believed that continuous tachypnea is an important symptom of Moebius syndrome.

Abducens Nerve↗
PubMed1993

Brainstem involvement in high functioning autistic children.

To determine involvements of the brainstem and/or cerebellum in autism, we compared midsagittal magnetic resonance images of the brains of high functioning autistic children with those of normal controls. We found that the midbrain and medulla oblongata were significantly smaller in these autistic children than in the control children. The pons area did not differ between the two groups, nor was there any difference in the cerebellar vermis area. The ratio of the brain stem and cerebellum to the posterior fossa area did not differ significantly between the high functioning autistic and the control children. A positive correlation between age and area of the cerebellar vermis was observed in autistic children but not in control children. Thus, it was suggested that significant anatomical changes in the midbrain and medulla oblongata existed in the autistic children and that growth of the cerebellar vermis in autistic children was different from normal children.

Adolescent↗
PubMed1993

Brainstem and cerebellar vermis involvement in autistic children.

Recent reports have suggested functional abnormalities of the brain stem in autistic children, and structural abnormalities have also been reported. We obtained magnetic resonance imaging (MRI) scans for 21 autistic children and compared them with 21 control MRI scans. The areas of the brain stem and cerebellar vermis were measured using midsagittal images. The brain stem and cerebellar vermis lobules VIII to X were found to be significantly smaller in autistic children. A positive correlation between the size of the brain stem and cerebellar vermis was observed in the autistic children. This correlation was not observed in the control children. This suggests that the size of the brain stem and cerebellar vermis are anatomically altered in autistic children and that growth of the brain stem and cerebellar vermis in autistic children is different from normal children.

Autistic Disorder↗
PubMed1993

[Pathophysiology of carbohydrate-deficient glycoprotein syndrome--neuroradiological and neurophysiological study].

Neuroradiological and neurophysiological studies were done in two male siblings with carbohydrate-deficient glycoprotein syndrome (CDGS) (case 1 and 2) and one male second cousin presumed with CDGS (case 3). Case 1 and 2 had abnormality of epileptic discharge in EEG. Case 1 had MCV in the lowest normal range, giant SEP was observed in SSEP in case 1 and low voltage of P 14 in case 3. Case 1 had low voltage of wave V in ABR and case 3 had low voltage of wave V on one side and no response on the other side. The all cases showed the normal pattern for VEP and MEP. All showed cerebellar hypoplasia and various degree of pontine hypoplasia on MRI. SPECT showed hypoperfusion in cerebellum, brainstem and left centroparietal region in case 1. In CDGS we found the hypoplasia of cerebellum and pons in common, but it was suggested that CDGS might have the heterogeneity of pathophysiology on the basis of various neurological abnormalities.

Adolescent↗
PubMed1993

[A successful repair of anomalous origin of right pulmonary artery from ascending aorta complicated with subdural hematoma, MRSA infection and postoperative intestinal perforation].

A 2-month-old male infant with anomalous origin of right pulmonary artery from ascending aorta who had subdural hematoma and MRSA infection due to the hemodynamic deterioration after cardiac catheterization was reported. The cardiac anomaly was successfully corrected by bypass grafting between the right pulmonary artery and the pulmonary trunk with an expanded polytetrafluoroethylene tube. This procedure without cardiopulmonary bypass was selected because of the presence of subdural hematoma and poor general conditions, and no signs of mediastinitis were noticed postoperatively in spite of the use of artificial material. But he had colostomy and drainage due to postoperative intestinal perforation. The complicated postoperative course of this patient recommends us the surgical correction of this anomaly without cardiac catheterization.

Aorta↗
PubMed1992

Distribution of saposins (sphingolipid activator proteins) in tissues of lysosomal storage disease patients.

Saposins are a group of small glycoproteins derived from a single precursor protein, prosaposin. Each of the four saposins are involved in lysosomal hydrolysis of various sphingolipids. Our recent investigations have shown that saposins accumulate in tissues of several lysosomal storage diseases patients, including those with Tay-Sachs disease and Gaucher disease. To obtain insight into the mechanism of accumulation and its pathological role, the subcellular distribution of saposins in brain from Tay-Sachs disease and in spleen of Gaucher disease were compared with that of GM2 ganglioside and glucocerebroside, respectively. In both Tay-Sachs brain and Gaucher spleen, saposins were found predominantly in light-density fractions while most of the GM2 ganglioside and glucocerebroside, respectively, were found in heavy-density fractions. These studies indicate that saposins that accumulate in these pathological tissues are not tightly associated with GM2 ganglioside or glucocerebroside.

Brain↗
PubMed1992

Reduced brainstem size in children with autism.

Recently, structural brain abnormalities as well as functional abnormalities of the brainstem have been reported in autistic children. The authors undertook an analytic study of the brainstem in autistic children by means of magnetic resonance imaging (MRI). The MRI scans of 29 autistic children were compared with 15 control MRI scans. The autistic children were divided into two groups according to DQ (IQ) level: the DQ (IQ) greater than or equal to 80 group and the DQ (IQ) less than 80 group. The midbrain and pons were measured, and the ratio of the midbrain and pons sizes versus the cranium size were calculated. The brainstem size was found to be significantly smaller in the autistic group. In particular, the reduction in brainstem size tended to be greater in the low DQ (IQ) group when compared with the high DQ (IQ) one, though there was no significant difference (p less than 0.1). This suggests that the brainstem is anatomically altered in autistic children.

Autistic Disorder↗
PubMed1992

Occipital deep white matter hyperintensity as seen by MRI: 1. Clinical significance.

Magnetic resonance imaging was performed in 270 patients with various neurologic complaints (1-15Y) with a 0.5 tesla superconducting imaging system using a field echo T1-weighted sequence and spin echo T2-weighted and PD-weighted sequences. Twenty-seven of them had deep white matter hyperintensity (DWMH) in the occipital lobe on T2-weighted images. The frequency of mild DWMH differed in different age groups, suggesting that mild DWMH may result from delayed myelination in the central nervous system. However, the frequency of severe DWMH, which was revealed as isointense relative to cerebrospinal fluid, did not differ in different age groups and it was significantly more common in severely retarded patients. Classification of DWMH based on the signal intensity is valuable to distinguish white matter abnormalities in the occipital lobe from delayed myelination in the same site.

Adolescent↗
PubMed1992

Electrophysiological study on hydranencephaly.

An electrophysiological study was performed on 2 children with hydranencephaly diagnosed by CT and/or MRI. Case 1 was a 4-month-old boy who had no rostral tissues above the midbrain. Case 2 was a 5-year-old boy in whom CT showed retention of the thalamus. Short latency somatosensory evoked potentials (SSEP) in both cases exhibited the absence of cortical activity (N1 and P4) with the preservation of waves of brain stem origin. However, in case 1, wave component No was not observed, while No was seen in case 2. It was postulated, thus, that the No component of SSEP on median nerve stimulation in children, which corresponds to N16 in adults, may originate in the thalamus.

Child, Preschool↗
PubMed1992

Magnetic resonance imaging of the brain structures in the posterior fossa in retarded autistic children.

Midsagittal magnetic resonance images of the brains of retarded autistic children were compared to those of non-autistic mental retardation patients and controls. We found that the whole brain stem and particularly two of its components (the midbrain and medulla oblongata) were significantly smaller in retarded autistic children and mental retardation cases than in control children. The pons area was significantly smaller in mental retardation cases as compared to control children but did not differ between autistic and control children. Moreover, there was no difference in the brain stem between retarded autistic children and mental retardation cases. We also noted no difference in the cerebellar vermis area among retarded autistic children, mental retardation cases and control children. The ratio of the midbrain to posterior fossa area was significantly smaller only in autistic patients. Although the significance of these results is unknown, further examination of autistic children with a normal IQ is necessary.

Autistic Disorder↗
PubMed1992

Circadian rhythm in patients with hydranencephaly.

Circadian rhythm and sleep were studied in three hydranencephalic infants who were diagnosed on the basis of computed tomographic and/or magnetic resonance imaging scans and electrophysiologic findings. In all three cases, although the active sleep cycle was preserved, quiet sleep decreased and indeterminate sleep increased. The sleep-circadian rhythm was disturbed in all three cases. The hormone secretion rhythm was studied in two cases (cases 1 and 3). In both cases, cortisol secretion showed two or three peaks during the day. In one case (case 3), growth hormone secretion did not show sleep enhancement. Prolactin secretion showed an increase during sleep in both cases. The circadian rhythm of body temperature appeared at 6 months of age and disappeared after 1 year of age in case 1. Case 2 did not show a circadian rhythm of body temperature, but case 3 did at 2 years 6 months of age. However, it was thought that the circadian rhythm of body temperature in case 3 was a false one due to severe opisthotonus. Thus, it is suggested that the development of the circadian rhythm may require the rostral brain structure more than the midbrain and that there may be multiple oscillators in humans.

Brain Stem↗
PubMed1991

Human placental sialidase complex: characterization of the 60 kDa protein that cross-reacts with anti-saposin antibodies.

Sialidase isolated from human placenta is associated with several proteins including acid beta-galactosidase, carboxypeptidase, N-acetyl-alpha-galactosaminidase, and others. These proteins are thought to form an aggregated complex during isolation of sialidase. One of the proteins of 60 kDa was recently identified by Potier et al. (Biochem. Biophys. Res. Comm. 173, 449-456, 1990) as a sialidase protein: this protein also cross-reacted with anti-prosaposin antibodies. We have isolated this protein and from the following evidence identified it as a heavy chain component of immunoglobulin G and not sialidase or a derivative of prosaposin. On gel filtration HPLC, sialidase activity and the 60 kDa protein were clearly separated from one another. The 60 kDa protein cross-reacted not only with antibodies raised against human saposins A, C, and D, but also with second antibody (goat anti-rabbit immunoglobulin G antibody) alone. This 60 kDa protein strongly cross-reacted with anti-human immunoglobulin G antibodies. The sequence of the initial 15 amino acids from the N-terminus of the 60 kDa protein was identical to the sequence of an immunoglobulin G heavy chain protein Tie (gamma 1).

Amino Acid Sequence↗
PubMed1991

Apparent response of subacute sclerosing panencephalitis to intrathecal interferon alpha.

An 8-year-old boy with subacute sclerosing panencephalitis (SSPE) was treated with 1.0 to 3.0 x 10(6) IU human interferon alpha (IFN) by the intrathecal route weekly or fortnightly. Pronounced improvement of clinical and electroencephalographic findings were observed in a dose-dependent manner. Our patient raises hope that IFN can induce sustained remission in patients with SSPE.

Child↗
PubMed1991

Central sleep apnea and arterial compression of the medulla.

We report a 5-year-old with central sleep apnea associated with compression of the medulla oblongata by abnormal looping of the left vertebral artery. The magnetic resonance imaging findings raise the possibility that compression of the respiratory center by an aberrant vertebral artery might cause central sleep apnea.

Brain Diseases↗
PubMed1991

Development of the brainstem: assessment by MR imaging.

The morphological development of the brainstem was studied by means of MR imaging. The subjects were 74 cases ranging in age from 4 months to 16 years, and 6 adult cases. The brainstem development was rapid until 4-6 years of age and thereafter it slowed down. That is the brainstem showed exponential growth (w', t', v and u). The relationship between brainstem growth and the cranium size was divided into 4 types as follows: 1) linear increase with development (s/T-O), 2) plateau (w/T-I and v/RTP-LTP), 3) down and up (u/RTM-LTM and z/RTM-LTM) and 4) exponential (t/T-P). In the values of v, z (the size of the brainstem in axial view) and t/T-P (the ratio of the midbrain and the cranium size in sagittal view), there were significant sex differences for cases of 10-16 years old. These values in male subjects were greater than those in female subjects (v, p less than 0.05, z, p less than 0.01, and t/T-P, p less than 0.05). That is the brainstem in male subjects was greater than that in female subjects.

Adolescent↗
PubMed1991

Congenital myotonic dystrophy associated with a chromosome pericentric inversion.

We report two cases of congenital myotonic dystrophy (CMyD) associated with a chromosome abnormality of pericentric inversion. Case 1 was a two-month-old boy, presented with 46 XY, inv (9) (p 11q 13). His father had the same chromosome abnormality without any clinical manifestations. His mother had clinical manifestations of myotonic dystrophy (MyD) but had no chromosomal aberration. Case 2 is a one-month-old girl, presented with 46 XX, inv (4) (p15.31q25). Her mother had clinical manifestations of MyD and the same chromosome abnormality as Case 2, but her father was normal. Our case report may be of value in adding further information on the pathogenesis of CMyD.

Chromosome Inversion↗