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Y Handa

Publications and source records attributed to Y Handa.

At least 91 records · Page 5Linked to original sources
PubMed1993

Development of the sympathetic innervation to the cerebral arterial system in neonatal rats as revealed by anterograde labeling with wheatgerm agglutinin-horseradish peroxidase.

In order to clarify the developmental pattern in the sympathetic nerve fibers innervating the cerebral arterial system during the postnatal period in rats, we labeled the postganglionic nerve fibers originating in the superior cervical ganglion (SCG) and directly observed their extension and plexus formation by means of anterograde labeling with wheat germ agglutinin-horseradish peroxidase (WGA-HRP). The WGA-HRP solution was injected into the right SCG 1-7 days after birth. The rats were killed 48 h after trace injection, and the cerebral arteries were reacted with tetramethylbenzidine, then observed as a whole mount preparation. The labeled nerve fibers appeared as a few relatively straight bundles with branching fibers running longitudinally to the long axis of the artery in the ipsilateral right side of the circle of Willis and proximal portion of their main branching arteries at 3 days after birth. The nerve fibers started to form a circular pattern of nerve plexus only on the wall of the circle of Willis as early as 1 week after birth. At the beginning of postnatal week 2, labeled nerve fibers extended the collateral projections into the collateral side of the circle of Willis, and these expanding projections could not be observed at postnatal week 3. We observed a route of the sympathetic nerve fibers advancing into the cerebral arterial system which has not been described in previous studies; bundle of labeled nerve fibers entered into the wall of the middle portion of the basilar artery in half of the animals, in any postnatal period.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Correlation between somatosensory-evoked potentials and magnetic resonance imaging of focal cerebral ischemia in cats.

Serial measurements of somatosensory-evoked potentials (SEPs) and magnetic resonance imaging (MRI) were performed in 17 cats for 24 h after unilateral middle cerebral artery occlusion. Intravoxel incoherent motion (IVIM) imaging demonstrated ischemic cerebral injury 2 h post-occlusion in all cats, while T2-weighted imaging failed to show clear evidence of injury until 2-6 h. In the severely affected group of eight cats as determined by SEP criteria, ischemic injury evaluated by MR imaging was detected extensively in not only the basal ganglia but also the frontoparietal cortex including part of the somatosensory center. In contrast, in the mildly affected group of nine other cats, ischemic injury was limited to the basal ganglia with or without some involvement of the lower temporal cortex. The quantitative signal intensity ratios in the frontoparietal cortex were significantly greater in the severely affected group than in the mildly affected group, but showed no difference between them in the basal ganglia.

Animals↗
PubMed1993

Technique of percutaneous electrode implantation for electrical pelvic floor stimulation.

A modified technique of electrical pelvic floor stimulation is described in detail. Six patients suffering from detrusor urinary incontinence underwent percutaneous electrode implantation for electrical pelvic floor stimulation. By this procedure adequate muscle contraction was obtained with a significant rise in urethral closure pressure. Detrusor reflex thresholds were increased in 5 of 6 patients at the initial stimulation. Percutaneous implantation appears to be an easy and noninvasive technique. This method provides stable and adequate effects on the pelvic floor structure and may be used in chronic electrical stimulation.

Adult↗
PubMed1993

The kinetics of lymphocyte subsets and macrophages in subarachnoid space after subarachnoid hemorrhage in rats.

BACKGROUND AND PURPOSE: Although it has been suggested that humoral immunity plays a role in the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage, there has been no quantitative assay for cellular immunity. We studied the kinetics of immune cells in the subarachnoid space after subarachnoid hemorrhage in the rat. METHODS: One hundred fourteen Sprague-Dawley rats were used in this study. The animals were divided into two groups and injected with either autologous blood (0.3 mL) or saline into the major cistern. They were killed at the specified time: 10 minutes or 1, 2, 3, 5, or 7 days after subarachnoid hemorrhage. For immunohistochemical analysis, the rats' whole brains were frozen, and cryostat sections were prepared. For flow cytometric analysis of immune cell presence, their whole brains underwent enzymatic digestion. RESULTS: Histopathologic study revealed pathological change of the arterial wall, and immunohistochemical study revealed the existence of macrophages and T cells in the subarachnoid space in animals with a survival time of 2 to 5 days after subarachnoid hemorrhage. A flow cytometric study revealed the peak of appearance of T cells and macrophages 2 days after subarachnoid hemorrhage. The helper-suppressor T cell ratio also reached a peak 2 days after subarachnoid hemorrhage. CONCLUSIONS: A serial response of immunoreactive cells, which resembles that of the chronic allergic reaction observed in autoimmune diseases or delayed-type hypersensitivity, exists in the subarachnoid space after subarachnoid hemorrhage. The present results suggest that the initial response in cellular immunity, which is followed by humoral immunity and eicosanoid reactions, plays a role in eliciting the development of cerebral vasospasm.

Animals↗
PubMed1993

Effect of systemic hypotension on cerebral energy metabolism during chronic cerebral vasospasm in primates.

The influence of systemic hypotension on cerebral blood flow (CBF) and energy metabolism during chronic cerebral vasospasm after subarachnoid hemorrhage was studied in 15 monkeys. Changes in the phosphorus spectrum, as demonstrated by in vivo phosphorus-31 (31P) magnetic resonance (MR) spectroscopy, or in regional CBF were measured in the parietal cortex during graded hypotension. Sequential changes in the phosphorus spectrum were observed during moderate hypotension in the animals 7 days after the introduction of an autologous blood clot around the right middle cerebral artery (MCA). Angiograms revealed a reduction in vessel caliber by approximately 50% in the right MCA. The mean CBF in the spasm side decreased in parallel with a decrease in the mean arterial blood pressure (MABP) from 120 to 40 mm Hg, indicating the abolition of autoregulation. There were no significant differences in the mean percentage totals of inorganic phosphate (Pi), phosphocreatine (PCr), adenosine triphosphate (ATP), and pH between the hemispheres at baseline MABP before hypotension. The values of PCr, ATP, and pH decreased significantly (p < 0.05) and Pi increased significantly (p < 0.05) at an MABP of less than 60 mm Hg in the involved hemisphere. The ratio of PCr:Pi decreased in parallel with a decrease in MABP. The ATP showed a stepwise decrease during moderate hypotension (MABP 60 mm Hg) and was reduced significantly 20 minutes after the beginning of hypotension (p < 0.05). The results indicate that, during chronic vasospasm, changes in cerebral energy metabolism are coupled with changes in CBF in the state of impaired autoregulation. There exists a critical level for ischemia below which high-energy phosphorus metabolites become markedly depleted. It is suggested that 31P MR spectroscopy may be useful to evaluate the ischemic vulnerability of brain tissue in order to prevent delayed neurological deficit during cerebral vasospasm.

Animals↗
PubMed1993

Histological studies of intracranial vessels in primates following transluminal angioplasty for vasospasm.

Percutaneous transluminal angioplasty for treatment of cerebral vasospasm was performed in primates. Chronic cerebral vasospasm was induced by placement of an autologous blood clot over the right internal carotid artery (ICA), middle cerebral artery (MCA), and anterior cerebral artery (ACA). Cerebral angiography on Day 7 showed that the diameters of the ICA, MCA, and ACA were reduced to 55.7% +/- 1.3%, 55.3% +/- 2.6%, and 59.6% +/- 1.3%, respectively, of baseline. The angioplasty was carried out with a silicone microballoon attached to a microcatheter under somatosensory evoked potential (SEP) monitoring on Day 7. The angioplasty for ICA was performed satisfactorily; however, the balloon could not be advanced to the spastic M1 or A1 portions of the cerebral artery. Following angioplasty, the diameters of the ICA, the M1 segment, and the A1 segment were 79.6% +/- 2.9% (p < 0.001), 67.6% +/- 4.3% (p < 0.05), and 61.7% +/- 2.2% (not significant), respectively, of baseline. Histological studies demonstrated that the vessels were well dilated and patent without endothelial cell damage.

Angioplasty, Balloon↗
PubMed1993

[Clinico-pathological study of Helicobacter pylori in early gastric cancer].

The role of Helicobacter pylori (Hp) infection in the pathogenesis of various gastric diseases is an important but unresolved issue. To investigate the association between Hp and the histological findings of the stomach in patients of early gastric cancer, the prevalence of Hp in gastric mucosa and the mucosal alterations were examined histo-pathologically in the surgically resected stomach of 30 cases with early gastric cancer. Serum IgG antibodies for Hp were determined in these cases. All 30 cases had evidence of Hp infection in resected stomach and 90% had Hp antibodies in their serum. There was no evidence of direct association between Hp and gastric cancer histopathologically, although it is considered that chronic gastritis (atrophy and intestinal metaplasia) are implicated in Hp infection.

Adenocarcinoma↗
PubMed1993

Electrical pelvic floor stimulation in the management of urinary incontinence due to neuropathic overactive bladder.

Electrical pelvic floor stimulation employing a portable functional electrical stimulation system with percutaneously indwelling electrodes was carried out to improve detrusor urinary incontinence. Cyclic stimulation using negative going pulse trains of 20 Hz was applied 3 to 6 times daily to the bilateral pudendal nerves distributing to the pelvic floor muscles for the purpose of strengthening these muscles, including the urethral sphincter, and simultaneously, suppressing detrusor overactivity and increasing cystometric capacity. Electrical training for 4-8 weeks resulted in an improvement of urinary incontinence in five of six patients. In two of six cases incontinence had subjectively disappeared. Urodynamic investigations demonstrated an increase in detrusor reflex threshold and less tendency for abortive detrusor contraction. No apparent complications were encountered during these periods. This procedure appears to be efficient for the management of patients with detrusor incontinence who respond poorly to conservative therapies.

Adult↗
PubMed1992

Electrical stimulation of pelvic floor musculature by percutaneous implantable electrodes: a case report.

A forty-year-old man with reflex urinary incontinence due to spinal cord injury was treated with electrical stimulation of the pelvic floor musculature. In this case we employed percutaneous implantable electrodes and an external pulse regulator. After 4 weeks of stimulation incontinence was improved and urodynamically maximum cystometric capacity increased from 220 ml to 350 ml. Our method is easy and not invasive. This technique can be an alternative for the electrical stimulation for urinary incontinence.

Adult↗
PubMed1992

Plasticity of the sympathetic nervous system innervating the cerebral arteries in rats.

In order to investigate the neuroplasticity of the peripheral sympathetic nervous system innervating the cerebral blood vessels, we observed and traced the sprouting nerve fibers originating in the contralateral superior cervical ganglion (SCG) into the previously denervated cerebral arteries following unilateral excision of the SCG and/or decentralization of the contralateral SCG in young rats (4 weeks old). These nerve fibers were labeled anterogradely with wheat germ agglutinin-horseradish peroxidase or stained immunohistochemically with anti-tyrosine hydroxylase antibody. Eight weeks after the right SCG excision, reinnervating nerve fibers originating in the contralateral ganglion formed a circular pattern of nerve plexus only on the wall of the main cerebral arteries of the circle of Willis in the ganglionectomized side. However, the decentralization of the contralateral SCG, which was performed simultaneously with a unilateral SCG excision, prevented the nerve sprouting into the denervated regions. Unilateral decentralization of SCG itself failed to affect their distribution pattern or their density of nerve fibers originating in the ganglion. It is concluded that in the young rat the outgrowth of the sympathetic nerve fibers into the denervated cerebral arteries was strongly impeded by the disconnection of ganglion cells from the central nervous system, while the decentralization alone could not affect the innervation pattern of the postganglionic fibers which have been already built-up in the cerebral arterial system.

Animals↗
PubMed1992

Effect of marrow perforation on the sheep temporomandibular joint.

The effect of surgically perforating the mandibular condyle to allow synovial fluid to contact the marrow was examined in 5 sheep temporomandibular joints. The surgical defect showed replacement of the marrow with fibro-osseous tissue and subcortical cysts. A vertical, central osteophyte emerged from the perforation, causing attenuation or perforation of the disc and temporal surface proliferation. These changes were radiographically and histologically similar to advanced osteoarthritis. This supports the concept that intraarticular micro or macrofracture may result in osteoarthritis.

Animals↗
PubMed1992

[Clinical and epidemiological aspects of enteritis due to Salmonella hadar. I. Isolation of S. hadar from sporadic diarrhea--clinical and bacteriological study].

Before 1983, S. hadar was seldom isolated from man, animals, food or the environment in Japan: only one strain having been isolated from man and one from the environment. In subsequent years there has been a progressive increase in the number of isolations. S. hadar is now one of the commonest serotypes isolated from cases of sporadic diarrhea in Shizuoka Prefecture (Table 1). However, the epidemiology of S. hadar is not clearly understood. Reports on the clinical features of S. hadar gastroenteritis are also scarce. We examined the clinical symptoms of 15 cases of S. hadar gastroenteritis. S. hadar was encountered in patients of all ages. Infants and young children below 10 years of age constituted 47% of all cases. Seventy per cent of young children below 10 years of age experienced fever of more than 39 degrees C. This incidence was significantly higher than that of general Salmonella gastroenteritis observed in our previous study, in which fever of more than 38 degrees C was noted in 61% of the children. We found one case of presumptive person-to-person spread. No other household contacts of index patients suffered from diarrhea during the same period. Systematic examination for Salmonella contamination was performed for poultry farms, broiler chickens, broiler processing plants and meat on the market. 259 Salmonella strains were isolated from 1197 samples. S. hadar accounted for 37.1% (96) of all isolations (259). A drug resistance test was performed for 51 strains of the diarrhea cases and 67 strains of the environment. The pattern of the distribution of MICs of 9 drugs was similar in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Clinical and epidemiological aspects of enteritis due to Salmonella hadar. II. Environmental contamination by Salmonella hadar in Shizuoka Prefecture--studies on the feasibility of reducing S. hadar infection].

A systematic examination was performed for environmental food contamination by Salmonella in poultry farms, broiler chickens, broiler processing plants and meat on the market. Salmonella was isolated from 219 of 1197 samples and the serotypes showed a wide distribution. (Table 1-1). S. hadar accounted for 37.1% (96) of all isolations (259). The contamination rate of broiler chickens on arrival at broiler processing plants is relatively low. However, in the broiler processing plants, containers, processing machinery, cooling water and slaughters were highly contaminated by Salmonella, S. hadar being the most prominent serotype in the plants. 64% of chicken meat on the market was contaminated by Salmonella, S. hadar being the second most prominent serotype. 11% of the pork and none of the beef or horseflesh was contaminated by Salmonella. These results indicate that poultry is the main source of S. hadar infection in humans. However, no S. hadar was isolated from cultures of 119 samples of feed for chickens from each delivery (Table 1-1). Thus, as the main source of infection by S. hadar of broiler chickens, an association with the feed seems to be ruled out. S. hadar was isolated at three of 18 poultry farms within Shizuoka Prefecture. Follow-up studies were performed at the three poultry farms which revealed that in two of them, Salmonella was completely eradicated on completion of disinfection. In the other one farm, which is still being disinfected, various strains of Salmonella including S. hadar still survived. We conclude that the main cause of the problem is the magnification of contamination of Salmonella-free material during the process at the broiler processing plants.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Effect of leukotriene antagonist on experimental delayed cerebral vasospasm.

Experimental delayed cerebral vasospasm was produced in 16 adult mongrel dogs by the "two-hemorrhage" method of intracisternal injections of autologous arterial blood. Group 1 was a control group. Group 2 was a treatment group that received an intravenous injection of ONO-1078, a novel potent leukotriene antagonist, once a day for 7 days just after the first cisternal injection of the blood. Angiography was performed on Days 0 and 7, and the cerebrospinal fluid levels of leukotriene C4 (LTC4) were measured on Days 0, 3, and 7. The cisternal levels of LTC4 increased after subarachnoid hemorrhage in both groups. But the cerebrospinal fluid levels of LTC4 in the treatment group were significantly lower than those in the control group (P less than 0.05). The angiographic vasospasm after subarachnoid hemorrhage was partially prevented with the treatment of intravenous injections of ONO-1078 (P less than 0.001). These results suggest that LTC4 may play a role in the pathogenesis of delayed cerebral vasospasm, directly or indirectly, and ONO-1078 may have a therapeutic effect on the prevention of the development of delayed cerebral vasospasm.

Animals↗
PubMed1992

Time course of the impairment of cerebral autoregulation during chronic cerebral vasospasm after subarachnoid hemorrhage in primates.

The time course of the impairment of cerebral autoregulation during chronic cerebral vasospasm after subarachnoid hemorrhage was studied in 18 monkeys. Changes in cerebral blood flow (CBF) at the regional level and central conduction times during either graded hypo- or hypertension were evaluated in these animals at three stages (3, 7, and 14 days) following the introduction of an autologous blood clot around the right middle cerebral artery (MCA). Angiograms revealed a reduction in vessel caliber (compared to the baseline level in the involved MCA) of 30% at 3 days, 50% at 7 days, and 10% at 14 days. At all stages, CBF remained constant at mean arterial blood pressures (MABP) of 60 to 160 mm Hg in the noninvolved hemisphere. In contrast, at the 3- and 7-day stages, there was an impairment of autoregulation in the involved hemisphere at MABP of 40 to 180 mm Hg. The right hemispheric CBF was significantly (p less than 0.05) lower than that in the left throughout the period of investigation at MABP below 120 mm Hg, but rose to exceed the left CBF at MABP above 180 mm Hg at the 7-day stage and 160 mm Hg at the 14-day stage. The right-sided central conduction time showed significant (p less than 0.05) prolongation at MABP below 60 mm Hg at the 3-day stage and 40 mm Hg at the 7-day stage. It is suggested that these results may help to develop guidelines for hemodynamic therapy for vasospasm in its various stages.

Analysis of Variance↗
PubMed1992

Functional electrical stimulation (FES) systems for restoration of motor function of paralyzed muscles--versatile systems and a portable system.

Multichannel functional electrical stimulation (FES) systems were developed to restore the motor functions of the paralyzed muscles, i.e. two kinds of versatile systems for laboratory use and a practical portable system were developed. The first microcomputer-based FES system was composed of an 8 bit microcomputer (PC-8801mkII) with a voice recognition board and 30 stimulation outputs, in which the voice commands were used for selecting a motion pattern, and for executing (start), (hold), (restart) and (stop) commands. In combination with the voice commands, a proportional control command detected from a head angle sensor was used for volitional control of motion. The second microcomputer-based FES system was composed of a 16 bit microcomputer (PC-9801 UV or compatible) with flexible control capabilities (e.g. respiratory sensors) for volitional control and with 64 stimulation outputs. An originally designed practical portable FES system was 89 x 145 x 31 mm in dimension and 380 g in weight. This paper describes the system configurations, the control methods of these FES systems and three examples of the clinical applications of the FES systems.

Electric Stimulation Therapy↗
PubMed1991

Patterns of reinnervation of denervated cerebral arteries by sympathetic nerve fibers after unilateral ganglionectomy in rats.

In order to clarify the manner in which previously denervated cerebral arteries become reinnervated after unilateral excision of the superior cervical ganglion (SCG), we observed directly the reinnervating sympathetic nerve fibers originating in the contralateral SCG by using anterograde labeling with wheat germ aggulutinin-horseradish peroxidase in rats. The nerve fibers sprouted from the nerve fibers in the contralateral anterior cerebral artery and reinnervated the arterial wall of the anterior cerebral artery of the denervated side as early as one week after ganglionectomy. In addition to this sprouting route, three other reinnervating nerve fiber routes were observed in the circle of Willis of the denervated side two weeks after ganglionectomy: the proximal portion of the internal carotid artery, the route passing between bilateral ethmodial arteries, and the posterior communicating artery. Eight weeks after ganglionectomy, these reinnervating nerve fibers formed a fairly dense plexus in a circular pattern in the circle of Willis. However, the reinnervation could not be observed in the arterial branches derived from the circle of Willis (middle cerebral artery and posterior cerebral artery) even 16 weeks after ganglionectomy. The present results clearly demonstrated the time course, distribution pattern and limitation of the reinnervation from the contralateral SCG following unilateral ganglionectomy. The fact that reinnervation could be observed only in the main cerebral arteries of the circle of Willis, in which the nerve plexus appeared to have a circular pattern, suggests a difference between the qualities of sympathetic innervation controlling the cerebral circulation in these arteries and the other arterial branches related to these differences in reinnervation capacity.

Animals↗