Imperceptible magnetic sensor matrix system integrated with organic driver and amplifier circuits.

Artificial electronic skins (e-skins) comprise an integrated matrix of flexible devices arranged on a soft, reconfigurable surface. These sensors must perceive physical interaction spaces between external objects and robots or humans. Among various types of sensors, flexible magnetic sensors and the matrix configuration are preferable for such position sensing. However, sensor matrices must efficiently map the magnetic field with real-time encoding of the positions and motions of magnetic objects. This paper reports an ultrathin magnetic sensor matrix system comprising a 2 × 4 array of magnetoresistance sensors, a bootstrap organic shift register driving the sensor matrix, and organic signal amplifiers integrated within a single imperceptible platform. The system demonstrates high magnetic sensitivity owing to the use of organic amplifiers. Moreover, the shift register enabled real-time mapping of 2D magnetic field distribution.

Wireless EEG patch sensor on forehead using on-demand stretchable electrode sheet and electrode-tissue impedance scanner.

A wireless electroencephalogram (EEG) sensor using a stretchable electrode sheet and electrode-tissue impedance measurement module is presented herein. The sensor can be attached to the forehead using biocompatible gel with the electrode sheet. The sensor is compactly designed for 3 cm × 9 cm × 6 mm with weight of 12 g. Impedance scanning circuit is also proposed to evaluate the skin surface condition before EEG measurements. We developed the impedance scanning board for 3 cm × 5 cm × 3 mm, with weight of 5.6 g. Results show that the proposed system demonstrates a promising performance in diagnosing the Alzheimer's disease using frequency domain analysis.

Therapeutic effect of secretin in patients with jaundice; double-blind placebo-controlled multicentric trial.

Secretin, a gastrointestinal hormone, has been shown to have a potent choleretic effect. Having already obtained some beneficial effects with secretin in patients with intrahepatic cholestasis, we sought to confirm its effects in a double-blind placebo-controlled study in patients with mild jaundice after acute or during chronic hepatitis, where total bilirubin level was in excess of 4.0 mg/dl for 3 days or more. Patients with primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), and familiar hyperbilirubinemia were excluded from the study. Ninety-three patients were included in this analysis, but the final evaluation covered 69 of them. No statistically significant differences were found in the reduction of serum bilirubin levels between secretin and placebo groups. As a number of patients with liver cirrhosis had been included, the subjects were subdivided into one group with cholestasis in hepatitis and one with liver cirrhosis. In the subgroup of cirrhotic patients who received secretin, serum levels of AST were significantly increased compared with the placebo group. However, since the choleretic effect of secretin is unique, further studies seem to be warranted.

Neurotological evaluation of Harada's disease.

We have had 30 patients with Harada's disease at our clinic from 1980 to 1993 and their neurotological findings were retrospectively reviewed. There were 12 males and 18 females, whose ages ranged from 15-years to 67-years. Preceding symptoms such as headache or common cold were observed in 50% of the patients. Pleocytosis of the cerebrospinal fluid was found in 89% of the patients. Subjective cochlear and/or vestibular symptoms were noted in 60% of the patients. In 43 of the 50 ears, sensorineural hearing loss (< 40 dB) was observed. In 77% of the patients, vestibular function tests gave abnormal results. On the basis of our findings, it was suggested that Harada's disease with vertiginous and cochlear symptoms could be classified as follows: cochlear type, peripheral vestibular type, cochleovestibular type, central type, and 'unclassified', based on the neurotological results.

Effect of hypergravity on vestibular compensation in guinea pigs.

The effect of hypergravity on vestibular compensation was studied in guinea pigs. Pharmacological labyrinthectomy was performed by injecting chloroform into the middle ear cavity under ether anesthesia. The guinea pigs were exposed to hypergravity on a centrifuge. The animals were divided into four groups: a group stimulated with 2G after labyrinthectomy of the right ear, a group stimulated with 2G after labyrinthectomy of the left ear to evaluate the influence of the centrifugal rotation, a group stimulated with acceleration and deceleration alone, and a control group which was maintained under similar conditions, but without centrifugation. Head deviation and nystagmus were recorded and analysed to assess the process of compensation at 1, 3, 5, 7 and 9 h after labyrinthectomy. The 2G-stimulated group showed faster compensation in head deviation than the control group. In this study, the hypergravity stimulation seemed to facilitate the compensation in head deviation.

Central disorders in vestibular neuronitis.

Between 1972 and 1993 equilibrium and audiological examinations were made on 73 patients who had been diagnosed to suffer from vestibular neuronitis. In 23 of these patients, central nervous disorders (CND) were suspected from the result of tests of positional and positioning nystagmus, smooth pursuit, optokinetic nystagmus or auditory brainstem response. In this group of patients the frequency of associated disorders and vertiginous symptoms (dizziness) was statistically higher than in the remainder 50 patients who did not have CND. In the CND group the time interval between the onset and improvement or disappearance of all vertiginous symptoms, nystagmus and canal paresis was longer than in the non-CND group.

Fine structures of utricle of developing chick embryo exposed to 2G gravity.

Utricular otoconia of the chick embryos incubated under continuous 2G load were examined under a scanning electron microscope. Morphological changes were confined to the process of otoconial formation and the otoconial size. Otoconial formation was remarkably delayed in the utricle of 2G centrifuged chick embryo. Giant otoconia, which sometimes amounted to over 100 microM in length, existed along the marginal zone of the utricular otolithic membrane. These results indicate that the 2G state influences the otoconical formation.

Enhanced MRI in patients with vestibular neuronitis.

Recent advances in magnetic resonance imaging (MRI) have demonstrated facial nerve enhancement in facial nerve palsy and cochlea enhancement in sudden deafness. However, no report has described the findings of enhanced MRI in vestibular neuronitis. Eight cases of vestibular neuronitis were studied with enhanced MRI. We did not detect any enhanced lesions of the vestibular nerve or ganglion. So far, as the present conditions of MRI are concerned, it is difficult to detect any enhancement in the vestibular nerve and ganglion. Further study will be required to evaluate the suitability of MRI for vestibular neuronitis.

[Equilibrium of small animals in "drop shaft" experimentation--preliminary study on the frog with vestibular neurectomy].

We have newly designed instruments for equilibrium experimentation, using a drop shaft, and studied the behavior and EMG Patterns of frogs with or without unilateral vestibular neurectomy, as a preliminary study at JAMIC (Japan Microgravity Center). The results are reported herein and the efficacy of the drop shaft in equilibrium experimentation is also documented. 1) In unilateral vestibular neurectomized frogs, posture--head tilt, leg flexion on the affected side, and leg extension on the opposite side--is maintained and persists under microgravity. Rolling to the affected side was also observed. 2) The latencies of the EMG responses from M. tibialis anticus and M. longissimus dorsi were prolonged on the affected side. 3) The frog is suitable for use in equilibrium experiments utilizing a drop shaft. 4) The JAMIC drop shaft can be used to obtain constant and stable microgravity, 10(-4) G for 10 sec, which is similar to that in space. Drop shafts are suitable for equilibrium experimentation.

A case of cerebellar infarction occurred with the 8th cranial nerve symptoms.

A rare case, 32-year-old man, of cerebellar infarction with the occurrence of the 8th cranial nerve symptoms was reported. On the neuro-otological examination, hearing test and caloric test showed a severe hearing loss and no response on the right side, respectively, and the spontaneous horizontal nystagmus fixed to the left direction was observed. Magnetic resonance (MR) imaging showed the infarctions in the areas of anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA) on the right side. On the 14th illness day, the 8th cranial nerve symptoms disappeared, and on the 12th illness day, right hearing level and caloric response were significantly improved. We suggested that such an early recovery of the subjective symptoms and neuro-otological findings may be attributable to the recanalized circulation disturbance or the development of collateral circulation.

High-resolution scanning electron microscopic study of cell organelles of the chick's vestibular ganglion.

The fine intracellular structures of the chick's vestibular ganglion were studied three-dimensionally using the scanning electron microscope (SEM) after freeze-fracturing with 50% dimethyl sulfoxide solution and placement in 0.1% osmium oxide solution. Three patterns of perikaryal myelination could be distinguished in the vestibular ganglion cells: heavily myelinated, lightly myelinated and unmyelinated. Intracellular organelles such as the Golgi apparatus, endoplasmic reticulum and mitochondria could be demonstrated clearly. The stereoscopic structures of the Schwann cells and nerve fibers were also clearly demonstrated.

[Motility of isolated vestibular hair cells induced by potassium].

Many studies of the outer hair cells in cochlea have demonstrated active motility. However, very few studies have been done on vestibular hair cells. This study was designed to demonstrate the motile responses of isolated vestibular hair cells of the chick, induced by potassium promoting contraction. Reversible cell shape changes were observed in 4 of 6 type I hair cells and 3 of 5 type II hair cells by applying the contraction solution. The cell shape changes were revealed mainly in the cuticular plate and infracuticular region. It was suggested that contraction in the cuticular plate of the isolated hair cells might be converted into tension which increases the stiffness of the sensory hairs and restricts their motions, based on the results of the present study, and the structure of contractile proteins and hair behaviors reported by previous investigators.

Vestibular compensation in vestibular neuronitis. Long-term follow-up evaluation.

We evaluated vestibular function, especially for positional, head shaking and caloric nystagmus, in 43 patients with vestibular neuronitis, for long periods from the onset. The results suggested that in these cases of vestibular neuronitis, which were studied for more than 10 years after onset of the disease, the disease may still be in the uncompensated stage or may have worsened in the partially compensated stage.

Motility of vestibular hair cells in the chick.

Recent studies of the outer hair cells in cochlea have demonstrated active motilities. However, very little study has been done on the vestibular hair cells (VHCs). The present study shows the motile response of the VHCs induced by application of Ca2+/ATP promoting contraction. Reversible cell shape changes could be shown in 10 of 16 isolated type I hair cells and 9 of 15 isolated type II hair cells by applying the contraction solution. Furthermore, the sensory hair bundles in the utricular epithelium pivoted around the base and stood perpendicularly to the apical borderline of the epithelium in response to the application of the same solution. It is suggested that the contraction of the isolated VHCs may be transferred to tension which causes the sensory hair bundles to restrict their motion in normal tissue, instead of changing the cell shape.

The otolithic organ in the developing chick embryo. Scanning electron microscopic study on the utricular macula.

The long and short axes of utricular maculae were measured to calculate growth curves using an ocular micrometer under stereomicroscope. The mean lengths of the long and short axes on the 6th incubation day were 0.06 mm and 0.05 mm, respectively. Thereafter: 1.00 mm and 0.74 mm on the 11th incubation day; 1.34 mm and 1.03 mm on the 15th incubation day; and on hatching 1.51 mm and 1.07 mm, respectively. The surface structure, particularly the otoconia and the sensory hairs of the utricular maculae, on the 4.5th incubation day to the 7th post-hatching day of White Leghorn chicks were observed with a scanning electron microscope (SEM). A number of microvilli and primary cilium on the inner surface of the otocyst were found between the 4.5th and the 5th incubation day. Immature sensory hairs appeared on the 5th incubation day. The polarity of the sensory hairs became evident on and after the 9th incubation day. Mature sensory hairs were seen all over the utricular maculae between the 1st and the 3rd post-hatching day. Mature sensory hairs were mainly seen near the striola, and immature ones peripherally. Then, the various forms in the maturation phase of sensory hairs were seen between the striola and the periphery. These arrangements suggest some process of maturity from the peripheral region to the central striola region. Immature otoconia were first seen on the 6th incubation day. Mature otoconia were recognized on and after the 11th incubation day, and they were observed on the whole surface of the utricular maculae. Global substances on the macula with a rough surface and spongy structure were observed suggesting otoconial precursors transforming themselves into otoconial crystals.

[Paranasal sinusitis due to Pasteurella multocida].

A case of paranasal sinusitis due to Pasteurella multocida (P. multocida) is reported. A 39-year-old woman presented with chief complaints of rhinorrhea and headache. The patient kept a cat in her house and kept such close contact with it as to wake up by being licked every morning. Bacteriological examination revealed P. multocida isolated from her nasal discharge and also from the saliva of the cat kept by the patient. The two isolates were compatible with respect to biochemical properties, serotype and drug susceptibility. Therefore, P. multocida infection in this case was considered to have originated from the pet cat. P. multocida infection has been increasing recently. One of the reasons is a pet boom. In order to prevent acquiring the infection from a pet animal, we should have knowledge about this infection, advise the patient to avoid close contact with pets, and provide valuable information concerning these problems to society from the viewpoint of zoonosis.

Vestibular endorgan of the frog after the space flight and postural alteration of the neurectomized frog--its morphological and functional resilience.

The vestibular organ of frogs returned from space were observed by SEM. Morphology of the sensory epithelia was normal, including ultrastructure, such as tip links and side links. The frogs' behavior and vestibular morphology after various types of vestibular neurectomy were studied. Vestibular neurectomy resulted in tilting posture toward that side. This tilting gradually decreased to zero and the nerve regenerated. When the same nerve was cut again after postural recovery, the tilting angle was smaller and recovery period was shorter than after the first neurectomy. When the bilateral nerves were cut and neural regeneration was inhibited on one side, tilting slowly developed toward that side. These results show that frogs' postural change is modified by both central compensation and peripheral vestibular function.

Biofeedback therapy in the treatment of tinnitus.

Seven patients were treated with electromyographic biofeedback therapy for intractable tinnitus which was supposed to be reinforced by mental distress and muscle tension. Three patients, who succeeded in decreasing electromyographic levels of the frontal muscle, were able to reduce tinnitus and relieve anxiety. One patient could eliminate tinnitus only during biofeedback sessions, but the efficacy was not continuous in daily life. The other three patients, who failed to decrease electromyographic levels, did not obtain favorable results. It is suggested that biofeedback therapy appears to be of greatest benefit when muscle tension and mental distress are the cause of magnification of the tinnitus symptoms.

Glial fibrillary acidic protein (GFAP)-like immunoreactivity in the vestibular endorgan of the rat.

The distribution of glial fibrillary acidic protein (GFAP)-like immunoreactivity in the peripheral vestibular nervous system of normal adult rats was studied using immunohistochemical methods. The immunoreactivity was demonstrated at the light-microscopic level. GFAP-like immunoreactivity could be seen at the vestibular fibers terminating in the hair cells.

Light and electron microscopic features of the rat vestibular ganglion cells.

The vestibular ganglion cells of the rat were characterized with regard to the cytoplasmic structure by light and electron microscopic observation. Light microscopy revealed four types of cells, depending upon the characteristics and distribution of Nissl granules. Electron microscopy gave a definite classification of these types by the arrangement and distribution of the roughly surfaced endoplasmic reticulum and neurofilament. The characteristics of the ganglion cells are discussed in relation to their size and function.