Yoichi Sakakihara

Efficacy and safety of immunization for pre- and post- liver transplant children.

Background. Infection is a serious complication after liver transplantation. Immunization is one means of controlling infections. The objective of this study was to investigate the efficacy and safety of simultaneous administration of several vaccines before transplantation and the efficacy and safety of administration under immunosuppressive conditions after transplantation. Methods. Fifty-eight patients who underwent living-related liver transplantation between April 1994 and March 2000 were included in this study. Simultaneous administration of a maximum of six vaccines was performed in a short period of time before transplantation. We also readministered vaccines to 15 patients with waning antibody titers after transplantation from June 1999. We investigated whether patients could seroconvert for measles, rubella, mumps, and varicella after immunization and how long antibody titers could be retained by measuring them several times throughout the period before and after transplantation. We also examined side effects caused by immunization. Results. The rates of seroconversion against measles, rubella, mumps, and varicella after the pretransplantation vaccination were 82%, 100%, 90%, and 95%, respectively. The rates of reseroconversion against measles, rubella, mumps, and varicella after the posttransplantation revaccination were 85%, 100%, 100%, and 71%, respectively. Although antibody titers against these viruses generally waned with time, no patient exhibited any serious illness or side effects. Conclusion. Although 12 of 58 patients (21%) had an infection, pretransplantation immunization was effective to prevent serious illness, especially for the 6 months after transplantation. Posttransplantation live-vaccine administration under immunosuppressive conditions is effective and safe.

DECREASED MEMBRANE FLUIDITY AND UNSATURATED FATTY ACIDS IN NIEMANN-PICK DISEASE TYPE C FIBROBLASTS

Niemann-Pick disease type C (NP-C) is an autosomal recessive disorder characterized by the sequestration and trapping of endocytosed cholesterol in lysosomes. The NPC1 gene on chromosome 18 was recently identified but its physiological function remains unknown. We have studied the lipid compositions of cultured human NP-C fibroblasts and mouse SPM-3T3 cell line derived from the C57BL/KsJ NP-C model mouse, which belongs to the same complementation group. Fibroblasts derived from apparently normal age-matched individuals and a subline of SPM-3T3 cells which restores cholesterol metabolism by transfer of human chromosome 18 were used as controls. Levels of free cholesterol in whole cell homogenates increased about 1.5-fold in human NP-C fibroblasts and mouse SPM-3T3 cells, while in the plasma membrane, cholesterol content did not significantly change in NP-C fibroblasts but rather decreased in SPM-3T3 cells. The total phospholipid content did not significantly change; however, among phospholipid head groups, increases in sphingomyelin and decreases in other classes were observed in human NP-C fibroblasts and mouse SPM-3T3 cells. The ratios of saturated fatty acids to unsaturated fatty acids increased in both human and mouse cells. The increase was also confirmed in the plasma membrane fraction of SPM-3T3 cells. Membrane fluidity was examined using a 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescent probe. The DPH anisotropy values were markedly increased in NP-C fibroblasts and in SPM-3T3 cells. The results suggest that a NP-C mutation causes complex alterations in cellular lipid contents and biophysical properties of the membrane.

Zonisamide - induced urinary lithiasis in patients with intractable epilepsy

We report here three patients with intractable epilepsy who developed urinary lithiasis during zonisamide (ZNS) treatment. Abdominal pain due to left-sided hydronephrosis was the initial symptom in the first patient, and it was resolved after the excretion of a stone. The second patient, who had no specific symptoms, was found to have a thick sludge of calcium phosphate in the bladder when he suffered from aspiration pneumonia and dehydration. The third patient, who had a history of recurrent urinary obstruction, was also found to have a thick sludge of calcium oxalate in the bladder. The urinalysis of the three patients revealed alkaline urine and hypercalciuria. Although their urinary lithiasis was resolved by discontinuation of ZNS and supportive therapy, routine examination of urine parameters such as pH and sediments, and daily urine-output checks are thought to be necessary during treatment with ZNS, especially for patients who are bedridden for a long time and receive multiple antiepileptic drugs.

Long-term ventilator-assisted children in Japan: a national survey

Owing to improved technology and care for patients who need mechanical ventilation, the quality of life as well as the prognosis for long‐term ventilator‐assisted patients has improved significantly in recent years. However, the increased number of these patients has raised economic, ethical and medical problems. In order to assess the magnitude of these problems, we conducted the first nationwide survey on the status of long‐term ventilator‐assisted children in Japan.

Long-term ventilator support in patients with Werdnig–Hoffmann disease

Abstract Background: Withholding and withdrawing life‐sustaining treatment for patients with Werdnig–Hoffmann disease (WHD) have been accepted as standard medical practice in most Western countries. However, a number of Japanese pediatricians are providing ventilator care for patients with this otherwise fatal disorder. We investigated the attitude of physicians in Japan who are providing ventilator care for patients with WHD.

AGE-ASSOCIATED CHANGES IN THE SYMPTOMATOLOGY OF GUILLAIN-BARRÉ SYNDROME IN CHILDREN

The medical records were reviewed of 83 children with Guillain‐Barré syndrome, with reference to the age‐associated changes found in the initial symptoms, the intervals between the preceding illness and the onset of disease, and the patterns of affected cranial nerves. A close correlation was observed between cranial nerve involvement and respiratory complications. The findings suggest the involvement of nervous system maturation in the clinical manifestations of Guillain‐Barré syndrome in children.

Magnetoencephalographic study of giant somatosensory evoked responses in patients with rolandic epilepsy

We report five patients with rolandic epilepsy associated with giant somatosensory responses to median nerve stimulation, in whom we analyzed the pathophysiologic relationship between rolandic discharges and the somatosensory responses using magnetoencephalography. Four of the five patients showed giant P30m, the current source of which was localized in the primary somatosensory cortex, while the first cortical response, N20m, was not enhanced, except in one patient. The current source of the giant middle-latency component, N70m, was localized posterior to that of N20m, possibly in the posterior parietal cortex, in all patients. The initial positive peak and large negative peak of rolandic discharges were identical to P30m and N70m with respect to the current source localization, wave form, topographic pattern, and time relationship in the electroencephalogram and magnetoencephalogram, and somatosensory evoked magnetic field and somatosensory evoked potential records, respectively. In addition, the secondary sensory cortex was considered to be the generator of the middle-latency component in one patient. In one patient, the current intensity of the N70m was normalized along with clinical improvement and the disappearance of rolandic discharges, whereas those of other somatosensory evoked magnetic field components remained unchanged. Our data suggest that the rolandic discharge generator mechanism in these patients could be closely related to the developmental alteration of excitability in the primary somatosensory cortex, posterior parietal cortex, and secondary somatosensory cortex, which decreased with age, and it could share a common neuronal pathway, at least in part, with the giant P30m-N70m (N90m) in the somatosensory evoked magnetic field through the sequential and parallel processing of somatosensory information. (J Child Neurol 2000;15:370-379).

New ocular movement detector system as a communication tool in ventilator-assisted Werdnig-Hoffmann disease.

A non‐contact communication system was developed for a ventilator‐assisted patient with Werdnig‐Hoffmann disease who had lost all voluntary movements except for those of the eye. The system detects the extraocular movements and converts them to either a‘yes’signal (produced by one lateral eyeball movement) or a‘no’signal (produced by two successive lateral eyeball movements) using a video camera placed outside the patients visual field. The patient is thus able to concentrate on performing a task without any intrusion from the detection system. Once the setting conditions of the device have been selected, there is no need for any resetting, as the patient is unable to move his body. In addition to playing television games, the child can use the device to select television channels, compose music, and learn written Japanese and Chinese characters. This seems to broaden the patients daily world and promote mental development.

Reduction of seizure frequency with clomipramine in patients with complex partial seizures

Two patients with complex partial seizures who had been refractory to various antiepileptics were treated with clomipramine. The frequency of the seizures was reduced to 0-30% of the original levels. It has been reported that imipramine is effective in absence and minor motor seizures, and its antiepileptic effect is thought to be related to the inhibition of the presynaptic re-uptake of serotonin and norepinephrine. The basic effect of clomipramine is the same as that of imipramine except that the inhibitory action of clomipramine on serotonin re-uptake is 5- to 10-times more potent than that of imipramine. It is implied that clomipramine may be of use in the treatment of partial epilepsies.

People with absolute pitch process tones with producing P300

We recorded a P300 component of event-related potentials associated with auditory oddball tasks in nine absolute pitch (AP) possessors and seven non-AP possessors. The previous studies demonstrated that AP possessors did not appear to employ working memory during auditory oddball tasks because they have a fixed tonal template in their memories. However, the present findings showed that the AP possessors exhibited similar P300 as the non-AP possessors and did update the tonal context in the auditory oddball tasks. This result suggests that the AP possessors do not always refer to the fixed tonal template in their memories when executing the oddball tasks and they employ working memory properly according to the difficulty of the auditory tasks.