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H Miwa

Publications and source records attributed to H Miwa.

At least 109 records · Page 6Linked to original sources
PubMed1999

[Primary progressive limb-kinetic apraxia: a case report with an electrophysiological study].

We report a 53-year-old right handed woman with a 5-year history of slowly progressive clumsiness of her right hand. Neurologic symptoms was otherwise unremarkable except for mild dysarthria. Brain CT and MRI revealed a focal atrophic change in the left precentral gyrus. She was thought to have the primary progressive limb-kinetic apraxia. Electrophysiological studies were performed to explore physiologic mechanism of her apraxia. Surface EMG revealed co-contraction of antagonistic muscles in her right upper extremity with rhythmic myoclonic discharges. C-reflex was positive after median nerve stimulation only on the affected side. SEPs elicited by the median nerve stimulation were not enlarged and the SEP recovery curves showed no abnormal facilitation or inhibition. In addition, the premyoclonus spike was demonstrated by Jerk-locked averaging. Transcranial magnetic stimulation using double pulse paradigm revealed a decrease in the level of cortico-cortical inhibition on the motor cortex in the affected side. Median nerve stimulation given prior to the transcortical magnetic stimulation on the size of the magnetic evoked potential (MEP) revealed abnormal facilitations on the affected side, especially at conditioning-test interval of 60-80 ms. Therefore, our results indicate increase in the excitability of motor cortical neurons in primary progressive limb-kinetic apraxia, likely due to a decreased excitability of cortico-cortical inhibitory mechanism as a result of focal degeneration of cortical neurons.

Apraxias↗
PubMed1999

[Idiopathic rabbit syndrome: a case report].

We report a patient with idiopathic oromandibular tremor resembling rabbit syndrome. The patient is a 36-year-old Japanese woman without any past and medical histories. On neurological examination, there was no abnormal finding except the oromandibular tremor. The tremor was confined to the jaw and perioral muscles. There was no extremity tremor. Laboratory findings were all normal, as well as her MRI and EEG. Surface EMG studies revealed that regular grouped discharges at a frequency of about 6 Hz appeared in the masseter, the orbicularis oris, and the digastric, and that the alternative contractions were found between the masseter and the digastric. Oral administration of tiapride was effective, but diazepam, trihexyphenydil, levodopa, and a beta-blocker were without effect. Although she had not taken neuroleptics, the appearance of the tremor was identical to the rabbit syndrome. The efficacy of the dopamine blockade may suggest that an abnormal basal ganglia function contributes to the pathophysiologic mechanism underlying this type of tremor.

Adult↗
PubMed1999

[Rhythmic involuntary movement of the neck in a patient with brainstem encephalitis].

A 36-year-old Japanese woman was admitted to our hospital, because of facial palsy, ophthalmoplegia, cerebellar ataxia, and rhythmic myoclonus of the neck. About a few weeks before admission, she developed symptoms of common cold and general fatigue. Her laboratory data were unremarkable, and her CSF was normal. Serum levels of antibodies to gangliosides were within normal limits. Her MRIs of the brain and neck were normal. Both somatosensory evoked cortical potential study and auditory evoked brainstem response study were normal. She was diagnosed as postinfectious brainstem encephalitis, and the administration of corticosteroid was started. After the treatment, her symptoms improved. To our knowledge, it is rare to see myoclonus to the neck without palatal tremor in patients with brainstem encephalitis.

Adult↗
PubMed1999

[The dissecting aortic aneurysm associated with polymyalgia rheumatica: a case report].

We report a patient with a dissecting aortic aneurysm associated with polymyalgia rheumatica (PMR). The patient is a 55-year-old Japanese man without a history of hypertension, diabetes mellitus and syphilis. He was admitted to an emergency hospital because of severe back pain, and was diagnosed as having a dissecting aneurysm of the descending aorta. After the admission, he began to notice severe muscle pain in his bilateral shoulder. Although his back pain gradually improved, his muscle pain progressively worsened, and his lower extremities were also involved. Then, he was introduced to our hospital. On neurological examination, he was alert and oriented. His cranial nerves were all intact. There was no muscle weakness nor sensory disturbance. Laboratory studies revealed that his erhythrocyte sedimentation rate was extremely high without elevation of the serum level of creatine phoshpokinase, rheumatoid factors and c-reactive protein. He was diagnosed as having PMR, and oral administration of prednisolone++ was started. Within several days, his muscle pain dramatically disappeared. As is known, there is a close relationship between PMR and temporal arteritis of giant cell arteritis. In general, PMR is a benign disease and responds well to steroid therapy, and prevalence of the giant cell arteritis is low in Japanese people. However, it should be kept in mind that the dissecting aneurysm is a relevant, severe complication of PMR because arteritis can be latently present in PMR.

Aortic Dissection↗
PubMed1999

[Epstein-Barr virus-associated hemophagocytic syndrome during mid-term pregnancy successfully treated with combined methylprednisolone and intravenous immunoglobulin].

A 32-year-old woman in the 16th week of pregnancy was admitted to our hospital because of high fever. Laboratory findings disclosed pancytopenia and extremely elevated serum LDH and ferritin levels. Coagulation tests showed disseminated intravascular coagulation. Serum soluble interleukin-2 receptor, tumor necrosis factor-alpha, and interleukin-6 levels were high, but serum interferon-gamma was below the detectable limit. Reactive Epstein-Barr virus (EBV) infection was diagnosed on the basis of a high titer of IgG antibodies to the EBV capsid antigen and early antigen. EBV was demonstrated in the peripheral blood and bone marrow cells by polymerase chain reaction. Mature histiocytosis and hemophagocytosis were detected in the bone marrow. A diagnosis of EBV-associated hemophagocytic syndrome (EBV-AHS) was made. Neither prednisolone (PSL 30 mg/day, P.O.) nor methylprednisolone (m-PSL) pulse therapy (1,000 mg/day for 3 days) induced a response. Thereafter, treatment with m-PSL pulse therapy (1,000 mg/day for 3 days) and i.v. administrations of high-dose immunoglobulin (20 g/day for 3 days) in combination with acyclovir (750 mg/day) and gabexate mesilate (2 g/day) induced remission of the disease. Maintenance therapy consisted of PSL (5 mg/day, P.O.) and camostat mesilate (600 mg/day, P.O.). The patient delivered a healthy male infant in the 35th week of pregnancy via natural birth. Reports of pregnant women with EBV-AHS are rare, and the choice of therapy has not yet been established. The present case study suggested the above combination treatment is useful and safe, and capable of changing the fulminant course of EBV-AHS during pregnancy without the use of anticancer drugs.

Acyclovir↗
PubMed1998

Postural effects of unilateral blockade of glutamatergic neurotransmission in the subthalamic nucleus on haloperidol-induced akinesia in rats.

The present study examined the postural effects of the local application of glutamatergic antagonists unilaterally into the subthalamic nucleus (STN), on haloperidol-induced akinesia in rats. After intracerebral injections of MK-801, a selective antagonist of N-methyl-D-aspartate (NMDA) receptor, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) disodium, a selective alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor antagonist, or vehicle, unilaterally into the STN, haloperidol was administered systemically and the elicited behaviors were assessed quantitatively. In rats which received injections of MK-801 or CNQX, but not vehicle, unilaterally into the STN, the administration of haloperidol induced contraversive dystonic posturing. The severity of the deviated posturing was dose-dependent. The present findings revealed that the overactivity of the STN under conditions of dopamine blockade is suppressed by interruptions of glutamatergic inputs, mediated via both NMDA or AMPA receptors, to the STN. Therefore, the present study may provide functional evidence in support of a recently proposed hypothesis, that not only disinhibition from the inhibitory globus pallidus efferents but also excitatory glutamatergic inputs to the STN actually contribute to the overactivity of the STN under dopamine-depleted conditions.

6-Cyano-7-nitroquinoxaline-2,3-dione↗
PubMed1998

Globus pallidus lesions inhibit the induction of c-Fos by haloperidol in the basal ganglia output nuclei in rats.

This study examined the induction of c-Fos expression in the substantia nigra pars reticulata (SNr) and entopeduncular nucleus (EP) in the rats with a globus pallidus (GP) lesion, following the administration of haloperidol. After a GP lesion was made unilaterally by stereotaxic administration of ibotenic acid, haloperidol was administered systemically, and the number of cells expressing c-Fos was quantitatively assessed. Haloperidol induced a high level of the expression of c-Fos in neurons of the SNr and EP, and the GP lesion significantly decreased the expression of c-Fos in the ipsilateral SNr and EP. Since it has been suggested that c-Fos expression in the SNr/EP is caused by increased excitatory inputs from the subthalamic nucleus (STN), the present results provide functional evidence indicating that neuronal activities of the basal ganglia output nuclei are not increased by GP ablation, unlike D2 receptor blockade, supporting the recently proposed hypothesis that overactivity of the STN resulting from dopamine depletion is not solely a result of disinhibition from inhibitory GP efferents.

Animals↗
PubMed1998

Recurrent cranial neuropathy as a clinical presentation of idiopathic inflammation of the dura mater: a possible relationship to Tolosa-Hunt syndrome and cranial pachymeningitis.

We report 14 patients with idiopathic recurrent cranial neuropathy, in whom multiple cranial nerves were involved recurrently, either at the same or different times, and appeared bilaterally. Oculomotor nerve involvement was most frequent, while the abducens and facial nerves were the next most frequent. Clinical courses were benign and not progressive, and the symptoms responded well to corticosteroids. Ten patients developed Tolosa-Hunt syndrome during the course of their illness. Laboratory findings and CSF were normal. MRI and CT studies were unremarkable, except for an asymmetric appearance of the cavernous sinus in some patients. One patient showed focal hypertrophic pachymeningitis in the posterior fossa in MRI. We discuss the relationship of the idiopathic recurrent cranial neuropathy with disorders characterized by inflammation of the dura mater, such as Tolosa-Hunt syndrome and cranial pachymeningitis.

Adult↗
PubMed1998

Dystonic posturing and circling behaviors induced by dopaminergic agents in rats with unilateral globus pallidus lesions.

The present study examined the behavioral effects of dopamine receptor agonists, antagonists, or N-methyl-D-aspartate (NMDA) glutamate receptor antagonist in rats with a unilateral excitotoxic lesion of the globus pallidus (GP). After the unilateral GP lesions were made by injections of the ibotenic acid, drugs were systemically given and the elicited behaviors were quantitatively assessed. Systemic administration of haloperidol, but not SCH23390, dose-dependently induced contraversive dystonic posturing in unilateral GP-lesioned rats. On the other hand, systemic administration of quinpirole, but not SKF38393, induced ipsiversive circling. MK-801, only when given at a high dose, unilateral GP-lesioned rat, the D2 receptor agonist and antagonist caused ipsiversive and contraversive posturing or circling, respectively. Since the rotational behavior is induced on the basis of asymmetry of the basal ganglia output activity, there must be a marked difference between the GP ablation and the administration of D2 receptor blockade on the basal ganglia output activity, supporting a speculation that overactivity of the basal ganglia under dopamine depletion is not solely a result of the disinhibition from the inhibitory GP efferents. The present unilateral GP-lesion model appears to be a useful one for the pharmacobehavioral investigation of D2-mediated mechanisms.

Analysis of Variance↗
PubMed1998

Effects of the globus pallidus lesion on the induction of c-Fos by dopaminergic drugs in the striatum possibly via pallidostriatal feedback loops.

c-Fos is one of the transcription factors contributing to the regulation of the downstream gene expression. Administration of dopamine D1 receptor agonist or D2 receptor antagonist have been known to induce c-Fos expressions in striatal projection neurons. We examined the effects of unilateral ablation of the globus pallidus (GP) on apomorphine- or haloperidol-induced expression of c-Fos in the striatum. Haloperidol induced a high level of c-Fos expression in the striatal neurons, predominantly those in the dorsal part, and the unilateral GP lesion caused by ibotenic acid increased the number of neurons exhibiting haloperidol-induced c-Fos expression in the striatum on the side with the GP lesion by about 2- or 3-fold. On the other hand, the unilateral GP lesion had no significant effect on the apomorphine-induced c-Fos expression in the striatal neurons. The present study provides evidence indicating that the activity of GP neurons may have an inhibitory influence on the induction of the immediate early genes by haloperidol in the striatal neurons, suggesting a function of the pallido-striatal feedback loops which have been identified anatomically.

Animals↗
PubMed1998

Granulocyte colony-stimulating factor and its receptor in acute promyelocytic leukemia.

Expression of granulocyte colony-stimulating factor (G-CSF) receptor (G-CSFR) and in vitro proliferative response to G-CSF were investigated by quantitative immunofluorescence and [3H] thymidine uptake, respectively, in a series of acute myeloid leukemias (AML). The results indicated that G-CSFR was detected at high levels in acute promyelocytic leukemia (APL) cells, in comparison with other types of AML. Moreover, APL cells were also seen to predominantly proliferate in response to G-CSF. Based on these observations, we administered recombinant human G-CSF to a patient with APL in the third relapse that was resistant to both cytotoxic agents and all trans retinoic acid, in an attempt to sensitize the leukemic cells to cell-cycle-dependent agents. Complete remission was achieved. The finding that APL cells are exquisitely responsive to G-CSF supports the view that G-CSF is useful for augmentation of their vulnerability to cell-cycle specific agents.

Adult↗
PubMed1998

Effects of teprenone on gastric epithelial restoration in a rabbit cultured cell model.

The mechanism of action of gastrocytoprotective agents is not fully understood. We assessed the effects of an anti-ulcer agent, teprenone, and bile acid on epithelial restoration. Teprenone with or without deoxycholic acid was added to a complete confluent cultured gastric epithelial cell sheet after wounding. Restoration was monitored for 48 h, and the wound size was assessed. Migration velocity was measured, and proliferation was detected by sequential staining with bromodeoxyuridine. The labeling index was calculated. Restoration was completed within 48h in controls, whereas deoxycholic acid retarded repair. The migration velocity was suppressed by deoxycholic acid treatment. The number of proliferative cells peaked at 36 h (labeling index, 1.7%) in controls. In the deoxycholic acid group, the maximal labeling index was 0.5% at 48 h. Teprenone abolished the bile acid-induced retardation. Teprenone showed cytoprotective effects against deoxycholic acid-induced inhibition of epithelial cell migration and proliferation.

Animals↗
PubMed1998

Relapsed duodenal ulcer after cure of Helicobacter pylori infection.

We report a patient--a 42-year-old man--who had suffered from recurrent duodenal ulcer for about 20 years. Successful curative therapy for Helicobacter pylori infection was performed for 2 weeks with new triple omeprazole, anoxicillin, clarithromycin (OAC) treatment in October 1995, and cure of the infection was repeatedly confirmed by histology, culture, and the 13C urea breath test. One month after the curative therapy, recurrence of a small duodenal ulcer was observed and in February another duodenal ulcer and reflux esophagitis occurred, with severe symptoms, despite the continuous administration of ranitidine. None of the examinations to reconfirm cure of the infection revealed the presence of H. pylori. As the patient experienced continual psychological stress and smoked more frequently during the recurrent episode and had not used nonsteroidal anti-inflammatory drugs, stress and smoking appeared to play important roles in the relapse of duodenal ulcer in this patient after cure of H. pylori infection.

Adult↗
PubMed1998

Marginal irregularity of flat elevated type of colorectal tumor as a marker of malignant potential.

BACKGROUND: The malignant potential of superficial elevated type tumors is still controversial. Because biopsy specimens alone are sometimes not sufficient for diagnosis due to histologic heterogeneity within the tumor, other clinical parameters for evaluation of the degree of malignancy would be helpful. METHODS: A new morphometric parameter, the "F-circle," which represents the irregularity of the tumor margin, was studied in 115 endoscopically recognized superficial, flat, elevated type colorectal tumors without a central depressed area with respect to histologic evaluation of the degree of malignancy. RESULTS: The mean F-circle values of adenomatous lesions with mild or moderate atypia, severe atypia, and adenocarcinoma were 0.709+/-0.115, 0.619+/-0.149, and 0.536+/-0.133, respectively. CONCLUSION: The superficial elevated type of colorectal tumor having more marginal irregularity had a greater malignant potential, and the F-circle may be a useful clinical parameter for evaluation of the degree of malignancy.

Adenocarcinoma↗
PubMed1998

Frequent expression of human Thy-1 antigen on pre-B cell acute lymphoblastic leukemia with t(9;22).

Thy-1 (CDw90) is a phosphatidylinositol-anchored protein, and is expressed on human pluripotential hematopoietic stem cells. The expression pattern of this antigen on leukemia cells is still controversial. In this study, 72 adult patients with pre-B cell acute lymphoblastic leukemia (pre-B ALL) were examined for the expression pattern of Thy-1 by using indirect immunofluorescence and reversed transcription polymerase chain reaction (RT-PCR) methods. Twelve cases were judged positive on the basis of conventional immunophenotype criteria. Thirteen cases showed a weak clonal shift on the fluorogram, even though their positive percentages were from 6.7% to 14.9%. Thy-1 gene transcripts were detected in all of the 13 cases showing a weak clonal shift. The study of antibody binding capacity, which was calculated by the mean fluorescence intensity of the test sample on the basis of a calibration curve using standard beads, showed that cases with more than 150 sites/cell could be positive. Thy-1 positivity in pre-B ALL was not associated with the expression of B-cell differentiation antigens. Thy-1 expression was significantly higher in pre-B ALL cases with karyotypic abnormalities than in those with normal karyotype (p = 0.0071). The t(9;22) abnormality was found in 18 of the 25 Thy-1+ cases. Simultaneous expression of transcriptional factors, GATA-2 and SCL, was frequently detected in the Thy-1+ cases. bcr-abl and GATA-2 are thought to play important roles in the proliferation of immature hematopoietic cells. Indeed, cell-cycle analysis showed that the cell population in the S/G2/M phase of the present Thy-1+ cases was less than that in the Thy-1- cases (p = 0.001770). Our data suggest that Thy-1 expression indicates the proliferative status of the leukemia cells, not their phenotypic immaturity.

Adolescent↗
PubMed1998

Biphasic expression of CD4 in acute myelocytic leukemia (AML) cells: AML of monocyte origin and hematopoietic precursor cell origin.

In 227 of 495 (45.9%) Japanese adult patients with acute myelocytic leukemia (AML), leukemic cells expressed CD4. Incidence of CD4 expression in each FAB subtype was as follows: M1 37.4%, M2 33.7%, M3 35.4%, M4 65.0%, and M5 78.3%. The typical expression pattern of myelomonocytic differentiation antigens and cytokine receptors in CD4+ AML was CD34lowCD33high CD11bhighGM-CSFRhigh. AML cases with 11q23 abnormalities and with inv(16) were frequently CD4-positive. These data collectively indicate that CD4 expression in AML cells is associated with monocytic characteristics. However, CD4+CD34high AML cases appear to have unique immature characteristics including low expression of myelomonocytic differentiation antigens (ie CD33 and CD11b), and accumulation of chromosome abnormalities (ie t(8;21) in CD4lowCD34high AML and chromosome 7 abnormalities in CD4highCD34high AML). We speculate that these leukemia subsets originate from CD4+ hematopoietic precursor cells, therefore then should be considered separately from most of the CD4+ AML as represented by CD34lowCD33high CD11bhighGM-CSFRhigh. Overall survival of patients with CD4+ AML in our series was worse than that of those with CD4 AML (P = 0.0202).

Adult↗
PubMed1998

Insulin-like growth factor I plays a role in gastric wound healing: evidence using a zinc derivative, polaprezinc, and an in vitro rabbit wound repair model.

BACKGROUND: Although the detailed mechanism is unclear, zinc and its derivative, polaprezinc, have been reported to accelerate gastric ulcer healing in vivo. AIM: To investigate the detailed cellular mechanism of polaprezinc on gastric epithelial cells and fibroblasts with special attention to insulin-like growth factor I (IGF-I). METHODS: Isolated rabbit gastric epithelial cells formed a complete monolayer, from which a circular artificial wound with constant size was made. The restoration process was monitored by measuring wound size up to 48 h. Either polaprezinc, IGF-I, fibroblast conditioned medium or neutralized medium conditioned by anti-IGF-I antibody was added at the time of wounding. The expression of mRNA of IGF-I, hepatocyte growth factor (HGF) and transforming growth factor alpha (TGF-alpha) in fibroblasts with or without polaprezinc treatment was tested using reverse transcription polymerase chain reaction (RT-PCR). Gastric epithelial cell proliferation was also examined by bromodeoxyuridine (BrdU) staining. RESULTS: IGF-I and fibroblast conditioned medium treatment accelerated gastric epithelial restoration which included cell migration and proliferation. However, polaprezinc and neutralized conditioned medium treatment did not accelerate epithelial repair. RT-PCR for growth factor mRNA revealed the IGF-I mRNA expression in fibroblasts was increased after treatment with polaprezinc. CONCLUSION: Polaprezinc induced IGF-I production from mesenchymal cells, resulting in stimulation of epithelial cell restoration through a paracrine pathway. IGF-I may play an important role in gastric wound repair.

Animals↗