[Issues of transition support to adulthood and the practices of pediatric-adult healthcare transition in neurological diseases].

A workshop of the Special Committee on Measures for Transition from Pediatric to Adult Health Care, the Japanese Society of Neurology was held to discuss various issues and practices involved in healthcare transition. The following points were addressed: (1) the history of, and issues involved in, promoting support for patients requiring medical care, (2) cooperation between pediatric medical centers and university hospitals, (3) collaboration between pediatrics and neurology in medical and rehabilitation facilities, and (4) a questionnaire survey of members of the Japanese Society of Neurology. The reasons for extreme difficulties in pediatric-adult healthcare transition for patients with neurological diseases, especially those who require continuous intensive medical care over a long period of time, include the difference in the operating systems of pediatric and adult departments, in addition to the difference in the diseases treated during childhood and adulthood. For holistic transition support, it is necessary to strengthen cooperation not only among medical professionals, but also among multiple professions, as well as between local communities and government.

Transition of deformation modes from bending to auxetic compression in origami-based metamaterials for head protection from impact.

For the protection of the human head by energy absorption structures, a soft mechanical response upon contact with the head is required to mitigate the effect of impact, while a hard mechanical response for highly efficient energy absorption is required to stop the movement of the head. This study realized the opposite mechanical properties during head protection by transitioning the deformation mode from bending to auxetic compression. First, non-linear finite element (FE) models were constructed to numerically reproduce the bending behavior. The calculated force responses agreed well with forces in bending tests. Using the FE models, the EA structures with proper transition of deformation modes were designed and installed in the seat headrests of real vehicles. Head protection was evaluated by dynamic loading in sled testing, in which the force on the head of the crash test dummy was measured. The head injury criterion improved from 274 to 155, indicating the superior performance of the tested structures compared to that achieved by energy absorption structures based on steel plates. Moreover, the deformation of auxetic structures prevented neck bending by holding the head. These findings present new possibilities for effectively protecting the human body by mitigating impact, facilitating energy absorption, and ensuring head stability.

Numerical simulations of magnetic resonance elastography using finite element analysis with a linear heterogeneous viscoelastic model.

ABSTRACT: Magnetic resonance elastography (MRE) is a technique to identify the viscoelastic moduli of biological tissues by solving the inverse problem from the displacement field of viscoelastic wave propagation in a tissue measured by MRI. Because finite element analysis (FEA) of MRE evaluates not only the viscoelastic model for a tissue but also the efficiency of the inversion algorithm, we developed FEA for MRE using commercial software called ANSYS, the Zener model for displacement field of a wave inside tissue, and an inversion algorithm called the modified integral method. The profile of the simulated displacement field by FEA agrees well with the experimental data measured by MRE for gel phantoms. Similarly, the value of storage modulus (i.e., stiffness) recovered using the modified integral method with the simulation data is consistent with the value given in FEA. Furthermore, applying the suggested FEA to a human liver demonstrates the effectiveness of the present simulation scheme.

Oxidative stress in patients with clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS).

We examined oxidative stress markers, tau protein and cytokines in the cerebrospinal fluid (CSF) in six patients with clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS). In the CSF, 8-hydroxy-2'-deoxyguanosine (8-OHdG) and hexanoyl-lysine adduct levels increased over the cutoff index in four and one out of six MERS patients, respectively. The CSF IL-6 and IL-10 levels were increased in three out of six patients, two of which had extended lesion of the cerebral white matter. The CSF value of tau protein, marker of the axonal damage, was not increased, and neuron specific enolase (NSE) in the CSF was not increased. The increased 8-OHdG levels in the CSF, DNA oxidative stress marker, in four MERS patients, suggesting involvement of oxidative stress in MERS. MERS is occasionally accompanied with hyponatremia, although our patients lacked hyponatremia. It is possible that the disequilibrium of systemic metabolism including electrolytes may lead to facilitation of oxidative stress and reversible white matter lesion in MERS. The increase of cytokine production seems to be involved in the distribution of lesions in MERS.

[Effects of piracetam therapy in a case of Lance-Adams syndrome].

We report a 17-year-old female patient with Lance-Adams syndrome caused by anoxic encephalopathy during a severe attack of bronchial asthma. She had difficulty in writing because of action myoclonus in her arms. She also exhibited freezing gait and was unable to walk without cane. Although her gait disturbance resembled those seen in patients with parkinsonism secondary to anoxic encephalopathy, surface electromyography revealed that it was caused by action myoclonus in her legs. The presence of giant somatosensory evoked potentials and enhanced cortical reflexes in response to the electrical stimulation to her posterior tibial nerves supported our diagnosis. A combined therapy with valproate sodium, clonazepam and piracetam (15 g/day) was not effective. However, her freezing gait remarkably improved and she was able to walk without help, after the treatment with sufficient dose of piracetam (21 g/day). Cortical hyperexcitability as revealed by electrophysiological examination also improved. We concluded that the combined therapy with antiepileptic drugs and piracetam was effective in the treatment for action myoclonus. However, because the effects seemed dose-related, the dosage of piracetam needed to be increased until the optimum effects were obtained.

[High-dose phenobarbital therapy is effective for the control of intractable tonic seizure with apnea in a case of multiple anomalies syndrome].

An 11-month-old boy with multiple surface anomalies and respiratory distress due to upper airway narrowing developed generalized tonic seizures coinciding with apnea. The ictal electroencephalography showed an abrupt onset of right-sided unilateral rapid activity with increasing amplitude followed by bursts of spike and wave complexes. The seizures were completely controlled with non-intravenous high-dose phenobarbital therapy. The serum level of phenobarbital at seizure control was 8 microg/ml. The serum level of phenobarbital peaked as high as 123 microg/ml; the patient developed neither liver function abnormality nor hypotension which necessitated any pressor agents. Although the patient was intubated, spontaneous respiration was intact after seizure control. Extubation, however, failed twice because of diminished cough reflex. After decrease of the phenobarbital dose and the development of drug tolerance, the patient was successfully weaned from respiratory support. High-dose phenobarbital therapy is effective for refractory epilepsy in patients complicated by respiratory distress. Although it was reported that respiratory depression was not severe with high-dose phenobarbital therapy, respiratory status may worsen in such patients due to the diminished cough reflex. Therefore the careful and prolonged management is essential.