Biomedical subjects

H Tanji

Publications and source records attributed to H Tanji.

At least 37 records · Page 2Linked to original sources

PubMed1999

Increases in [3H]FK-506 and [3H]L-N(G)-nitro-arginine binding in the rat brain after nigrostriatal dopaminergic denervation.

Receptor autoradiographic technique was studied to investigate sequential changes in FK-506 binding proteins, nitric oxide synthase and dopamine uptake sites in the brain 1 week to 8 weeks after unilateral 6-hydroxydopamine injection of the medial forebrain bundle in rats. [3H]FK-506, [3H]L-N(G)-nitro-arginine and [3H]mazindol were used to label FK-506 binding proteins (immunophilin), nitric oxide synthase and dopamine uptake sites, respectively. [3H]FK-506 binding showed about 13-25% increase in the ipsilateral striatum from 2 to 8 weeks after degeneration of nigrostriatal pathway. However, no significant change in [3H]FK-506 binding was observed in the ipsilateral substantia nigra during the postlesion periods. In the contralateral side, [3H]FK-506 binding also showed about 13-25% increase in the striatum from 2 to 8 weeks postlesion. The substantia nigra showed a 21% increase in [3H]FK-506 binding only 2 weeks after the lesioning. On the other hand, [3H]L-N(G)-nitro-arginine binding showed about 21-31% increase in the parietal cortex and striatum 1 week or 2 weeks postlesion. In the contralateral side, a 21% increase in [3H]L-N(G)-nitro-arginine binding was found in the dorsolateral striatum only 1 week postlesion. In contrast, degeneration of nigrostriatal pathway caused a conspicuous loss of [3H]mazindol binding in the ipsilateral striatum (87-96%), substantia nigra (36-73%) and ventral tegmental area (91-100%) during the postlesion periods. In the contralateral side, no significant changes in [3H]mazindol binding were observed in these areas up to 8 weeks after the postlesion. The present study demonstrates that unilateral injection of 6-hydroxydopamine into the medial forebrain bundle of rats can cause a significant increase in [3H]FK-506 and [3H]L-N(G)-nitro-arginine bindings in the brains. In contrast, a marked reduction in [3H]mazindol binding is observed in the brains after the lesioning, indicating severe damage to nigrostriatal dopaminergic pathway. These results suggest that immunophilin and nitric oxide synthase may play some role in the pathogenesis of neurodegenerative disorders such as Parkinson's disease.

Animals↗

PubMed1999

Allograft transduction of IL-10 prolongs survival following orthotopic liver transplantation.

Interleukin-10 (IL-10) is an ideal candidate cytokine for suppressing the alloimmune response in transplantation. To determine whether genetic modulation of the hepatic graft with IL-10 could prolong survival following orthotopic liver transplantation, we constructed a replication-deficient adenovirus vector expressing human IL-10 (AdCMVhIL-10). Intraportal injection of this vector into a donor rat 24-48 h before grafting resulted in efficient release of IL-10 into the circulation of a recipient rat after transplantation. Moreover, levels of hIL-10 from the suprahepatic vena cava were significantly (1.48-fold) higher than those from the infrahepatic vena cava (P = 0.013), indicating local IL-10 production within the transduced hepatic graft. AdCMVhIL-10 induced a prolongation of median survival to more than 87 days, with two of five transduced grafts showing more than 100 days of ongoing survival, when compared with 11 days for grafts transduced with a control adenovirus vector carrying the E. coli beta-galactosidase gene (P = 0.0021) and 11 days for untreated grafts (P = 0.0021). Pathological findings occurring in the AdCMVhIL-10-transduced hepatic grafts revealed no evidence of progressive rejection reaction resulting in graft failure. These results demonstrate that hepatic grafts modulated by IL-10 gene transfer make local and effective immunosuppression feasible in the transplantation setting.

Adenoviridae↗

PubMed1998

Sequential changes of dopaminergic receptors in the rat brain after 6-hydroxydopamine lesions of the medial forebrain bundle.

We investigated the sequential patterns of changes in dopamine uptake sites, D1 and D2 receptors in the brain of animals lesioned with 6-hydroxydopamine using quantitative receptor autoradiography. The rats were unilaterally lesioned in the medial forebrain bundle and the brains were analyzed at 1, 2, 4 and 8 weeks postlesion. Degeneration of the nigrostriatal pathway caused a significant loss of dopamine uptake sites in the ipsilateral striatum, substantia nigra (SN) and ventral tegmental area (VTA) in the lesioned animals. Dopamine D1 receptors were significantly increased in the ventromedial part of striatum of the ipsilateral side from 2 to 4 weeks postlesion. In the ipsilateral SN, a transient increase in dopamine D1 receptors was observed only 1 week after lesioning. However, the frontal cortex, parietal cortex and dorsolateral part of the striatum showed no significant change in dopamine D1 receptors throughout the experiments. On the other hand, dopamine D2 receptors were decreased increased in the ipsilateral SN and VTA from 1 week to 8 weeks postlesion. In the ipsilateral striatum, dopamine D2 receptors were increased in the dorsolateral part from 2 weeks to 8 weeks and in the ventromedial part from 2 weeks to 4 weeks. However, the frontal cortex and parietal cortex showed no significant change in dopamine D2 receptors during postlesion. In the contralateral side, most of regions examined showed no significant change in dopamine uptake sites, dopamine D1 receptors and dopamine D2 receptors during postlesion except for a transient change in a few regions. These results demonstrate that 6-hydroxydopamine can cause a severe functional damage in dopamine uptake sites in the striatum, SN and VTA. Our findings also suggest that the up-regulation in dopamine D2 receptors is more pronounced than that in dopamine D1 receptors in the brain after 6-hydroxydopamine treatment. Furthermore, our results support the existence of dopamine D2 receptors on the neurons of SN and VTA. Thus, our findings provide insights into the pathogenesis of Parkinson's disease.

Adrenergic Agents↗

PubMed1998

PET study of striatal fluorodopa uptake and dopamine D2 receptor binding in a patient with juvenile parkinsonism.

We studied pre-synaptic and post-synaptic function in the striatum of a patient with juvenile parkinsonism (JP) using positron emission tomography (PET). [18F]6-fluorodopa (18FDOPA), 11C-YM-09151-2 and [18F]fluoro-2-deoxy-d-glucose (18FDG) were used to measure fluorodopa uptake, dopamine D2 receptor binding and glucose metabolism, respectively. In this patient, 18FDOPA accumulation was decreased markedly in the caudate nucleus and the putamen bilaterally. In the images of 11C-YM-09151-2 and 18FDG, in contrast, no conspicuous changes were observed in the striatum. Thus our PET studies using 18FDOPA, 11C-YM-09151-2 and 18FDG provide a useful approach for assisting the diagnosis of JP, because the present findings are different from the results in patients with dopa-responsive dystonia and hereditary progressive dystonia with marked diurnal fluctuation. Furthermore, our findings are of particular interest in relation to the pathogenesis of JP.Copyright Lippincott-Raven Publishers

Journal Article↗

PubMed1998

[Bone and joint tuberculosis in the field of orthopedics].

In Japan the number of patients with bone and joint tuberculosis has been dramatically decreasing since the beginning of 1980's. The number of patients was 1626 in 1978 according to statistics of tuberculosis patient in Japan. This was only 2.02% of new tuberculosis patients of Japan in 1978. Since that time the number of patients with bone and joint tuberculosis, in Japan, has been in steady decline. The number was only 675 patients in 1996. This was only 1.34% of new tuberculosis patients. The rate of new infections also decreased. Recently due to the development of computed tomography, magnetic resonance imaging and so on, patients with bone and joint tuberculosis can be diagnosed early, with great certainty. Curettage of infected focus and bone grafting via anterior approach has resulted in consistently improved results. While there are many reports of about the operative treatment with spinal instruments for spinal tuberculosis, artificial materials must be implanted with great care.

Humans↗

PubMed1997

Presence of adrenomedullin-like immunoreactivity in the human cerebrospinal fluid.

The presence of adrenomedullin-like immunoreactivity in the cerebrospinal fluid was studied by radioimmunoassay in 13 subjects with various neurological diseases. The concentrations of adrenomedullin-like immunoreactivity in the cerebrospinal fluid were 9.4 +/- 3.1 pmol/l (mean +/- SD, n = 13). Reverse-phase high performance liquid chromatography of the extract of the pooled cerebrospinal fluid showed that approximately 40% of the adrenomedullin-like immunoreactivity was chromatographically identical to human adrenomedullin (1-52). This is the first report that demonstrates the presence of adrenomedullin-like immunoreactivity in the human cerebrospinal fluid.

Adrenomedullin↗

PubMed1997

Thermal gelation profile changes in reconstituted actomyosin due to storage under a high salt concentration and low temperature.

Changes in the heat-induced gelation properties of reconstituted rabbit skeletal actomyosin stored under a high salt concentration at pH 6.0 and 0 degree C were investigated at different weight ratios of actin to myosin by using dynamic rheological and biochemical measurements. The addition of actin resulted in a pronounced peak maximum at about 50 degrees C and an accompanying temporary reduction in the range at about 50 degrees C to 60 degrees C. The more the initial actin concentration was increased, the greater was the area of the peak/shoulder. However, this area was markedly diminished with increasing storage time. As a result, the dynamic rheological pattern was transformed from an actomyosin type into a myosin type. The relationship between the G' value at 80 degrees C and the actin/myosin weight ratio was curvilinear, with a peak at the ratio of 0.05, immediately after storage was started. This profile changed during storage, depending on the extent to denaturation of actin and myosin in the reconstituted actomyosin (RAM). The G' value of actomyosin in 0.5 M KCl with a small actin/myosin ratio of 0.05 decreased to one-half of its initial value after 7 days of storage, whereas the G' value with a large actin/myosin ratio of 0.225 increased by about 1.6 times. In 1.5 M KCl, all the G' values declined to the level with myosin alone after 7 days of storage. The time-course plots of the remaining actin concentration in RAM at different weight ratios of actin to myosin after being treated with 0.5 M or 1.5 M KCl showed a decrease in the actin content with increasing storage time, and an increase in the KCl concentration to 1.5 M KCl promoted the denaturation of actin in RAM faster than with 0.5 M KCl. The surface hydrophobicity of each RAM sample progressively increased with increasing storage time, while little significant increase in the sulfhydryl (SH) content during storage was observed. It is concluded that changes in the heat-induced gelation properties of actomyosin during storage are largely attributable to the denaturation of actin rather than to the denaturation of myosin or to quantitative changes in the SH content and hydrophobicity.

Actins↗

PubMed1997

[PET study of dopamine metabolism and dopamine D2 receptor in juvenile parkinsonism].

Positron emission tomographic(PET) study using 18F-6-fluoro-L-dopa (18FDOPA) can provide efficient information on the pre-synaptic function of nigrostriatal dopaminergic neurons. In juvenile parkinsonism(JP), the accumulation of 18FDOPA is markedly decreased in the caudate nucleus and putamen on both hemispheres. This finding is different from those in dystonia syndromes such as dopa-responsive dystonia (DRD) and hereditary progressive dystonia with marked diurnal fluctuation(HPD), and it is rather similar to late onset of Parkinson's disease. Furthermore, we studied dopamine D2 receptor binding activity on the post-synaptic sites of the striatum using 11C-YM-09151-2(11C-YM), a highly selective dopamine D2 receptor antagonist. In JP, 11C-YM was highly accumulated in the striatum, and D2 receptor binding activity is not significantly different from that of age-matched young normal subjects, but much higher than that of aged subjects. This finding suggests that post-synaptic dopamine receptor function keeps still normal or hypersensitive in JP, and may be different from other degenerative disorders such as multiple system atrophy. Glucose metabolism using 18F-fluoro-2-deoxy-D-glucose(18FDG) was also within normal range in the cerebral cortex in JP, but was more increased in the striatum than in the cerebral cortex in some patients. These PET studies can provide efficient informations about the pathologic condition of JP.

Age of Onset↗

PubMed1997

[PET study using 6-[18F]-fluorodopa in Parkinson's disease].

6-[18F]-fluorodopa (FDOPA) was developed as an analogue of L-DOPA across the blood-brain-barrier and to carry into nigrostriatal dopaminergic neurons. PET study using FDOPA revealed presynaptic dopaminergic function in the striatum of nigrostriatal system of the human brain and many studies have performed to clarify the pathogenesis of Parkinson's disease. FDOPA is also an efficient tracer to analyze pharmacokinetics of L-DOPA by measuring radioactivities of its metabolites in the peripheral blood by HPLC and to evaluate pharmacological effects on dopamine metabolism by pretreatment of dopa decarboxylase inhibitor or COMT inhibitor. PET study using FDOPA is useful not only to diagnose Parkinson's disease but also to differentiate from parkinsonism in combination with other radioactive ligands and with other neuroimaging methods such as MRI.

Animals↗

PubMed1997

A case report of midgut nonrotation treated by laparoscopic Ladd procedure.

We performed laparoscopic survey and treatment on a 17-year-old girl who was diagnosed as having complete midgut nonrotation. The Ladd procedure was successfully performed laparoscopically. The patient was discharged 6 days after the operation. Laparoscopic operation is a useful tool for the correct diagnosis and treatment of intestinal malrotation disease in the adult patient.

Adolescent↗

PubMed1997

Laparoscopic transhiatal esophagectomy for advanced thoracic esophageal cancer.

We performed transhiatal subtotal esophagectomy under laparoscopic guidance to reduce the invasiveness of subtotal esophagectomy while preserving dissectional accuracy. In six cases of advanced thoracic esophageal cancer with distant metastasis, we used a special type of handpiece of ultrasonic surgical aspirator (CUSA) for laparoscopic surgery to dissect the esophagus from surrounding tissues and to isolate vessels entering it while viewing with the video monitor. Hemostasis of isolated vessels was effected by clips or electrocoagulation. There was no massive bleeding from the mediastinum during the operation, nor was there postoperative bleeding or infection. All patients regained normal swallowing ability and were discharged. Transhiatal esophagectomy under laparoscopic guidance is considered a safe, less invasive operative treatment for patients who are suffering from advanced thoracic esophageal cancer.

Aged↗

PubMed1996

Brain 6-[18F]fluorodopa metabolism in early and late onset of Parkinson's disease studied by positron emission tomography.

We measured 6-[18F]fluorodopa (FDOPA) uptake in the caudate nucleus and the putamen of 20 patients with early and late onset of Parkinson's disease (EOPD and LOPD) and 20 normal control subjects using positron emission tomography. The mean influx rate constant values (Ki) were significantly reduced in the caudate nucleus and the putamen of the patients with EOPD and LOPD compared with age-matched control groups (p < 0.01), respectively. There were significant negative correlations between Ki values in the caudate nucleus (r = -0.67, p = 0.0024) and the putamen (r = -0.67, p = 0.0014), and duration of disease in the LOPD group compared with the EOPD group. Similar negative relationships between Ki values and clinical stages by Hoehn and Yahr and degrees of main clinical symptoms (bradykinesia, tremor and rigidity) were more markedly seen in the LOPD group than in the EOPD group. The present results suggest that the function of presynaptic dopaminergic terminals correlates well with clinical disease severity and degrees of main symptoms in the LOPD group, but not in the EOPD group. We speculate that compensatory up-regulatory function in the postsynaptic dopaminergic receptors may modify disease severity and the degrees of main clinical symptoms of EOPD.

Adult↗

PubMed1996

PET study of cerebral glucose metabolism and fluorodopa uptake in patients with corticobasal degeneration.

We measured cerebral glucose utilization and fluorodopa metabolism in the brain of patients with corticobasal degeneration using position emission tomography. The clinical pictures are distinctive, comprising features referable to both cerebral cortical and basal ganglionic dysfunctions. Brain images of glucose metabolism can demonstrate specific abnormalities with a marked asymmetry in the parietal cortex (the primary motor and sensory cortex and the lateral parietal cortex), the thalamus, the caudate nucleus and the putamen of the dominantly affected hemisphere related to clinical symptoms in six patients. [18F]dopa uptake also reduced in an asymmetric pattern, both the caudate nucleus and the putamen in four patients. This unique combination study measuring both cerebral glucose utilization and fluorodopa metabolism in the nigrostriatal system can provide efficient information about the dysfunctions which are correlated with individual clinical symptoms.

Aged↗

PubMed1995

[Progressive cerebellar ataxia and distal amyotrophy of Charcot-Marie-Tooth type with hyperglutamataemia:two sibling cases].

We reported two sibling cases of progressive cerebellar ataxia accompanied with muscular atrophy of Charcot-Marie-Tooth (CMT) type. Autosomal recessive inheritance was suggested because of the parental consanguinity and other family history. The first symptom was ataxic gait in their teens, and speech disturbance appeared later. Subsequently weakness and muscular atrophy developed in the four limbs in their thirties or forties. These symptoms slowly progressed. Neurological examinations revealed weakness, muscular atrophy, and disturbance of superficial and deep sensation in the distal parts of all limbs. Deep tendon reflexes were absent in the four limbs. There were no pyramidal tract signs, nor dementia. Sural nerve biopsy demonstrated the axonal degeneration without any findings suggesting hypertrophic neuritis. MRI study revealed marked cerebellar atrophy. Although plasma amino acid analysis showed elevated glutamate levels in both cases, activities of glutamate dehydrogenase in leukocytes was not reduced. Here, we propose a new disease entity of hereditary cerebellar ataxia and sensorimotor neuropathy associated with elevated plasma glutamate levels. Abnormal glutamate metabolism may be related to the pathogenesis of this disease.

Adult↗

PubMed1992

MRI of anterior spinal artery syndrome of the cervical spinal cord.

Cervical spinal cord lesions in the anterior spinal artery syndrome were delineated on magnetic resonance images (MRI) in four patients. The lesion was always seen anteriorly in the cervical cord. On T2-weighted images, the lesions appeared hyperintense relative to the normal spinal cord, while on T1-weighted images, two chronic lesions appeared hypointense, with local atrophy of the cord. In one case, repeated T1-weighted images showed no signal abnormality 4 days after the ictus, but the lesion became hypointense 18 days later, when contrast enhancement was also recognized after injection of Gd-DTPA; this sequence of intensity changes was similar to that of cerebral infarction. The extent of the lesion seen MRI correlated closely with neurological findings in all cases. Although the findings may not be specific, MRI is now the modality of choice for confirming the diagnosis in patients suspected of having an anterior spinal artery syndrome.

Adult↗

PubMed1989

Effects of dorsal column spinal cord stimulation (DCS) on reversibility of neuronal function--experience of treatment for vegetative states.

We have reported that DCS (dorsal column stimulation) improves the clinical symptoms of cases in persistent vegetative states. Since then, we have accumulated 23 cases who have been treated by DCS. We describe the clinical EEG, rCBF, and biochemical changes in cerebrospinal fluid (CSF) caused by DCS in patients in persistent vegetative states: (1) eight of these cases showed good clinical improvement; (2) most patients were young and the CT scan did not show large, diffuse, definite or bilateral low density areas in cortex, brainstem of thalmus; (3) neurostimulation increased rCBF (cerebral blood flow) in many parts of the brain in cases with vegetative states; blood flow increased in the cerebrum, cerebellum and brainstem; (4) neurostimulation enhanced the metabolism of catecholamines in CSF, NE, DA, DOPAC, HVA, and 5HIAA increased, but 3MT and 5HT decreased in CSF. DCS increased rCBF, enhanced the metabolism of catecholamines in CSF, and improved the EEG in patients in persistent vegetative states.

Cerebrovascular Circulation↗

PubMed1988

[A case of malignant lymphoma, an anemone cell tumor of the leg, arising from osteomyelitis].

An 80-year-old man, complaining of multiple fungating growth on his right leg, was hospitalized. A review of his previous history revealed that he had undergone three operations because of repeating osteomyelitis. A clinical examination showed that a tumor was localized on the right leg. Light microscopy revealed that tumor was composed of diffuse large round cell proliferations. Malignant lymphoma was suspected, but was difficult to distinguish in the undifferentiated carcinoma. Electron microscopically, extensive cytoplasmic processes resembling microvilli from the circumferential surface membrane were observed, but desmosomes, tonofilaments, secretory products or basal lamina were not seen. Immunohistochemically, IgG was demonstrated on the tumor cells. These findings led us to diagnoses an anemone cell tumor, originating from a malignant lymphoma and arising from osteomyelitis.

Aged↗

PubMed1988

[Effects of neurostimulation on the reversibility of neuronal function: experience of treatment for vegetative status].

UNLABELLED: Developments in the diagnostic procedures, microsurgical techniques, intensive care, and the social rescue system have lowered the mortality in cerebrovascular diseases, head injuries and other emergencies of neurology and neurosurgery. However, this decreased mortality has given rise to a new social and medical problem i.e. vegetative status, which is an increase in the number of people who live on with mild or severe residual neurological deficits. During the last two years, we have used dorsal column stimulation (DCS) for improving spasticity of hemiplegics. While doing so, we incidentally found an improvement in the EEG in some of the cases. This led us to use dorsal column stimulation in cases of vegetative status. In this paper, we describe methodology and our experience with ten cases of vegetative status. All cases satisfied the definition of "vegetative status" and had received medical treatment for more than 3 months prior to DCS without showing any clinical improvement. A neurostimulator made by "Medtronic Neuro" was used. The neurostimulator was implanted in epidural space, in midline, at C-2 level under general anaesthesia. Video recording of clinical conditions, EEG, rCBF and catecholamine metabolism in CSF at regular intervals were monitored to see the efficacy of this treatment. RESULT: 1) There was an improvement in the EEG in nine cases out of ten cases after neurostimulation. This was in the form of appearance of more wide spread alpha-waves, and was noticed between 3 to 14 days after starting the neurostimulation. 2) Four of these cases showed good clinical improvement. In the other four cases there was slight clinical improvement.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗