Search PubMed⌕ Search

Biomedical subjects

Hideaki Hayashi

Publications and source records attributed to Hideaki Hayashi.

10 recordsLinked to original sources
PubMed2003

Hyperproliferation of synapses on spinal motor neurons of Duchenne muscular dystrophy and myotonic dystrophy patients.

Synapses on the motor neurons of patients with Duchenne muscular dystrophy (DMD) and myotonic dystrophy (MD) were studied immunohistochemically using antibodies against synaptobrevin and synaptophysin. Some motor neurons showed hyperproliferation of synapses on the soma and the proximal dendrites. Hyperproliferated synapses were non-cholinergic, because they were not identified with antibodies against vesicular acetylcholine transporter. Regeneration of motor nerve terminals in patients with muscular diseases may affect reorganization of the subsets of central synapses.

Aged↗
PubMed2003

ALS patients on TPPV: totally locked-in state, neurologic findings and ethical implications.

Seventy patients with ALS using tracheostomy positive pressure ventilation (TPPV) were evaluated for impaired communication. Severely impaired communication is divided into the totally locked-in state (TLS) and the minimal communication state (MCS). TLS occurred in 8 of 70 (11.4%). In the 33 patients on TPPV for more than 5 years, TLS developed in 6 (18.2%) and MCS in 11 (33.1%). Respiratory management for ALS allows long-term survival if mechanical ventilation is used.

Adult↗
PubMed2003

[A case of lumbar intradural and epidural abscesses presenting with elevated serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9)].

An 81-year-old woman was admitted to our service because of high fever and severe lumbar pain. Neurological examination showed a nuchal stiffness and sensory disturbance of the lower extremities. CSF findings showed significantly elevated neutrophils and decreased glucose. MRI demonstrated intradural and epidural abscesses within the lumbar canal. In early stages of the disease, we unexpectedly found the elevated serum CEA and CA19-9. Although those tumor markers showed very high titers, we never found any evidence of the malignant tumor. Interestingly, those markers obviously decreased with the improvement of the abscess within the lumbar canal. We discussed the importance of CEA and CA19-9 in the infectious neurological diseases.

Abscess↗
PubMed2003

[Appearance of numerous lobulated fibers after a protracted course of 18 years in a case of dermatomyositis].

A woman aged 47 first noticed weakness in her proximal muscles of all four limbs at the age of 29. After the initial investigation at our hospital, she was diagnosed as having dermatomyositis associated with primary biliary cirrhosis. In the following 18 years, she was kept on steroids. Although she responded to this treatment, weakness progressed slowly necessitating re-investigation including a second muscle biopsy. It was remarkable that in her first muscle biopsy, no lobulated fiber had been, while they were numerous in the second one. As a result of these studies, possibilities of limb-girdle muscle dystrophy (LGMD) and other myopathies remained but were ultimately ruled out after immunohistochemical/and genetic studies, and the original diagnosis was confirmed. Her weakness responded to an increased dose of steroids. Lobulated fibers were originally described in LGMD, and were reported also in the facioscapulohumeral muscular dytrophy and other hereditary myopathies. They have been rarely described in the inflammatory myopathies. Based on the observation of the present case, we concluded that lobulated fibers have little disease specificity and can newly appear in the course of any chronic myopathies including acquired myopathies like dermatomyositis.

Anti-Inflammatory Agents↗
PubMed2002

Repeated administration of ketamine may lead to neuronal degeneration in the developing rat brain.

BACKGROUND: This study was conducted to investigate, in vivo, the dose and duration effects of ketamine administration on neuronal degeneration in the developing rat brain. METHODS: Seven-day-old (P7) Sprague-Dawley rats were treated with intraperitoneal injections of ketamine, a noncompetitive N-methyl-D-aspartate receptor antagonist. Degenerating neurones were identified by the cupric-silver stain from 10 brain regions using the stereological disector method. RESULTS: A single dose of ketamine (25, 50 and 75 mg.kg-1) did not increase neuronal degeneration compared with the saline-treated control. However, repeated doses of ketamine (25 mg.kg-1) at 90-min intervals over 9 h increased degenerating neurones in seven out of 10 brain regions. CONCLUSIONS: These findings suggest that the duration of ketamine exposure correlates with increased neuronal degeneration in the developing rat brain.

Animals↗
PubMed2002

Does ultrasound imaging before puncture facilitate internal jugular vein cannulation? Prospective randomized comparison with landmark-guided puncture in ventilated patients.

OBJECTIVE: To investigate whether prepuncture ultrasound evaluation of vascular anatomy facilitates internal jugular vein cannulation compared with landmark-guided puncture. DESIGN: Prospective randomized study. SETTING: Single community hospital. PARTICIPANTS: Adult patients undergoing general anesthesia (n = 240). INTERVENTIONS: The right internal jugular vein was cannulated using either anatomic landmarks or prepuncture ultrasound (3.75/7.5 MHz) guidance. In the landmark group, respiratory jugular venodilation was used as the primary landmark for locating the vein. Results of cannulation and the incidence of complications were compared. MEASUREMENTS AND MAIN RESULTS: Patients were randomly assigned to the ultrasound or landmark group. Respiratory jugular venodilation was identified in 188 patients (78.3%), in whom results of cannulation did not differ between the 2 techniques with respect to the venous access rate (cannulated at the first attempt: 83.5% in the landmark v 85.7% in the ultrasound group), the success rate (cannulated within 3 attempts: 96.9% v 95.6%), and the incidence of arterial puncture (1.0% v 3.3%). In the remaining 52 respiratory jugular venodilation-unidentified patients, the access rate (30.4% v 86.2%, p < 0.001) and the success rate (78.3 v 100%, p < 0.05) were significantly better in the ultrasound group, and no arterial puncture was recorded in the ultrasound group, whereas the incidence was 13.0% in the landmark group. The results were similar regardless of the ultrasound frequency used. CONCLUSION: Prepuncture ultrasound evaluation did not improve the result of right internal jugular vein cannulation compared with the respiratory jugular venodilation-guided approach. When the landmark was not observed, however, the prepuncture ultrasound guidance was helpful in facilitating the cannulation.

Adult↗
PubMed2002

[Application of bispectral index (BIS) monitoring to anesthetic management of posterior spinal fusion in a patient with Duchenne muscular dystrophy].

A 12-year-old boy with Duchenne muscular dystrophy underwent posterior spinal fusion for progressive scoliosis. Preoperative evaluation was focused on respiratory function as well as cardiac function, which revealed markedly reduced respiratory reserve (FVC 0.77 l, %FVC 25.9%, FEV1.0 0.48 l, %FEV1.0 62%) and well-preserved biventricular function. A possible association between malignant hyperthermia and Duchenne muscular dystrophy has been documented. Thus anesthesia was administered without triggering agents. Propofol and fentanyl were used for induction and maintenance of anesthesia, and the patient was ventilated with O2-nitrous oxide mixture. The anesthesia machine, prepared by using a disposable circuit and fresh CO2-absorbent and disconnecting the vaporizers, was flushed with O2 at a rate of 10 l.min-1 for 20 minutes before use. A small dose of vecuronium was administered while monitoring the train-of-four ratio. The bispectral index (BIS) was utilized to optimize the depth of anesthesia so that the wake-up test could be performed promptly on surgeon's request while avoiding the intraoperative awareness. The BIS was helpful in continuously assessing the wakening process. BIS increased from 40's to 80's in 15 minutes after discontinuation of propofol and nitrous oxide during the test. The patient was kept under close observation postoperatively without any sign of malignant hyperthermia.

Anesthesia, General↗
PubMed2002

[Hydrocephalus after subarachnoid hemorrhage regressing spontaneously through the subgaleal layer: case report].

Spontaneous regression was recognized in a case of hydrocephalus after subarachnoid hemorrhage. The regression resulted after the absorption of cerebrospinal fluid through the subgaleal layer. The absorption of cerebrospinal fluid through this layer takes a long time but is one of nature's physiological pathways. The spontaneous regression of hydrocephalus through the subgaleal layer may be temporarily useful until a more effective physiological pathway is provided by a shunt operation to deal with hydrocephalus.

Cerebrospinal Fluid↗