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T Urabe

Publications and source records attributed to T Urabe.

At least 37 records · Page 2Linked to original sources

Colocalization of Bcl-2 and 4-hydroxynonenal modified proteins in microglial cells and neurons of rat brain following transient focal ischemia.

Bcl-2 has a role in suppressing the production of reactive oxygen species and lipid peroxidation. To explore the in situ localization of 4-hydroxy-2-nonenal (HNE)-modified proteins and the Bcl-2 oncoprotein, we used double immunofluorescence labeling and confocal imaging in the rat brain after 3 h of middle cerebral artery (MCA) occlusion followed by reperfusion. Immunoreactivity for HNE or Bcl-2 was not detected at 1 h, but appeared in some intact neurons in the boundary between the infarcted and non-infarcted zones at 12 h. At 48 h, HNE-positive microglia were colocalized with Bcl-2 in the infarcted area and the boundary zone. Bcl-2 may play an important role in the antioxidant system promoting survival of the neurons and activated microglia following reperfusion injury.

Aldehydes↗

Gastrointestinal amyloidosis secondary to hypersensitivity vasculitis presenting with intestinal pseudoobstruction.

A 22-year-old woman developed sudden hepatic encephalopathy and severe intestinal bleeding. She was diagnosed with acute fatty liver and hypersensitivity vasculitis and was successfully treated with whole plasma exchange, methylprednisolone pulse therapy, and transcatheter arterial embolization. Twenty-seven months later, she began complaining of lower abdominal fullness, tenderness, and nausea and vomiting. Histologic examination showed that she had developed gastrointestinal and renal amyloidosis with intestinal pseudoobstruction and proteinuria. The immunohistochemical study of the stomach, rectum, and kidney with anti-amyloid A fluorescent antibody showed that the systemic amyloid deposit was secondary to her underlying disease. This is the first report of amyloidosis occurring secondary to hypersensitivity vasculitis.

Adult↗

[An 81-year-old woman with progressive motor disturbance, extrapyramidal features, dementia, and oculomotor palsy].

We report an 81-year-old woman who presented with motor disturbance in her right hand which was followed by parkinsonism, dementia, and supranuclear gaze palsy. She was well until her age of 73 (1989) when she had an onset of difficulty in using her right hand; she did not have weakness. She also developed small step gait. These symptoms had progressively become worse. She was admitted to our hospital in July of 1992 when she was 75 years old. On admission, she was alert and oriented, but she showed some difficulty in recent memory. She did not have aphasia or ideomotor apraxia, but she showed limb-kinetic apraxia in her right hand, ideational apraxia, dressing apraxia, constructional apraxia, tactile agnosia, and left-right disorientation. Alien-hand syndrome was observed in her right hand. Ocular movement was within normal limit for her age. She had oro-lingual dyskinesia. Otherwise, cranial nerves were intact. She walked in small-steps. She had rigidity and fine myoclonic movements in her right upper extremity. Deep reflexes were within normal limits and symmetric. Superficial and deep sensations were intact. Laboratory findings were unremarkable. She was discharged on August 15, 1992 for outpatient follow-up. Her motor and mental symptoms were progressive. By October of 1992, she developed supranuclear vertical gaze palsy, marked rigidity in the neck, and astereognosis. By June 1993, she became unable to walk without support. MRI taken in May of 1994 revealed atrophy of insular cortices, temporal lobe tips and parietal lobes more on the left side; the third ventricle was slightly dilated. She was admitted to another hospital on June 30, 1994. She had become a bed-ridden state with marked dementia and dysphagia. She developed fever on November 5, 1996 and expired on December 16 of the same year. She was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had corticobasal degeneration. Other diagnoses entertained included progressive supranuclear palsy, pallidonigroluysian atrophy, diffuse Lewy body disease, and Pick's disease. But the most of the participants agreed with the chief discussant's diagnosis. Post-mortem examination revealed aspiration pneumonia in the lungs and liver fibrosis apparently due to viral hepatitis. In the central nervous system, frontal and parietal lobes were atrophic more on the left side. Atrophy was accentuated in the superior frontal gyri, precentral and postcentral gyri, and superior and inferior parietal lobuli. Neuronal loss and astrocytosis were seen in these regions with scattered ballooned neurons. The substantia nigra showed marked neuronal loss and gliosis; neuronal loss was also seen in the pars reticulata. The outer and inner segments of globus pallidus and the periacqueductal gray matter showed gliosis, however, no apparent neuronal loss was seen. Putamen, subthalamic nucleus, and the dentate nucleus were preserved. Pathologic changes were consistent with the diagnosis of corticobasal degeneration. It was interesting to note that anti-tau immunostaining and Gallyas staining revealed neuropil threads and astrocytic plaques in the cortical areas, and intracytoplasmic inclusion bodies in the cortical neurons; these inclusions were not stained by Bodian stain. Tuft-shaped astrocytes which may be seen in progressive supranuclear palsy were not observed in this patient. Although corticobasal degeneration and progressive supranuclear palsy share some neurological features in common, this patient showed typical pathologic changes of corticobasal degeneration.

Aged↗

Effects of lidocaine and diltiazem on ventricular tachyarrhythmia and dispersion of conduction during severe myocardial ischemia in canine hearts.

The purpose of this study was to investigate the effects of lidocaine and diltiazem on ventricular tachyarrhythmia and dispersion of conduction during severe myocardial ischemia in dogs. Myocardial ischemia was produced by a 10-min occlusion of the left anterior descending artery by the retrograde blood flow technique. Saline, lidocaine, and diltiazem were infused intravenously before and during occlusion in groups A (n = 16), B (n = 22) and C (n = 13), respectively. The incidence of ventricular tachycardia (VT) consisting of ten or more VPC was 19% in group A, 73% in group B and 31% in group C (A vs. B, P < 0.01), and that of ventricular fibrillation (VF) was 31%, 64%, and 15%, respectively (A vs. B, P < 0.05). The time of the onset of VT preceding VF was shorter in group B than in group A (207.9 +/- 13.9 vs. 353.2 +/- 70.7 sec, P < 0.05). The time taken to reach maximal dispersion of conduction delay in the epicardium was shorter in group B than in group A (192.1 +/- 11.9 vs. 337.5 +/- 38.2 sec, P < 0.01), and the dispersion of conduction delay in the intramyocardial layers was smaller in group B than in group A (229.9 +/- 24.5 vs. 360.0 +/- 35.6 sec, P < 0.01). The time taken to reach maximal dispersion of conduction delay in the endocardium was greater in group C than in group A (400.8 +/- 38.8 vs. 274.4 +/- 23.9 sec, P < 0.01). However, there were no significant differences among the three groups with regard to the maximal dispersion of conduction delay in the epicardium, in the endocardium, or intramyocardial layer. These results suggest that lidocaine increased ventricular tachyarrhythmia due to an acute increase in dispersion of conduction in the epicardium and intramural layer, and that diltiazem was not effective in preventing ventricular tachyarrhythmia and did not affect the dispersion of conduction in the epicardium or intramural layer despite improvement in the endocardium.

Animals↗

Postischemic accumulation of lipid peroxidation products in the rat brain: immunohistochemical detection of 4-hydroxy-2-nonenal modified proteins.

We report an immunohistochemical study on the distribution and alterations of 4-hydroxy-2-nonenal (HNE)-modified proteins, an indicator of lipid peroxidation, in the rat brain after 3 h of middle cerebral artery (MCA) occlusion followed by reperfusion. HNE immunoreactivity was not observed in intact neurons, but it appeared in some shrunken neurons within the infarcted zone at 3 h after reperfusion. The number of HNE-positive neurons increased with the spread of the infarcted area. The pyramidal neurons in the third layer of the frontoparietal cortex were HNE-positive and the intensity of their HNE immunoreactivity was highest at 24 h after reperfusion. At 48 h, HNE-positive neurons were observed in the medial part of the striatum, the lateral side of the frontoparietal cortex, and at the boundary between the infarcted and noninfarcted zones. In addition, strong HNE immunoreactivity was seen in microglia (identified by OX-42 immunostaining). This method seems to be useful to follow the progress of lipid peroxidation at the cellular level after ischemic injury.

Animals↗

Effects of lidocaine and diltiazem on recovery of electrophysiologic activity during partial reperfusion following severe myocardial ischemia in canine hearts.

The effects of lidocaine and diltiazem on recovery of electrophysiologic activity during partial reperfusion following severe myocardial ischemia were investigated in 28 dogs. The left anterior descending artery was ligated, and the distal end was connected to the carotid artery. Myocardial ischemia was induced by retrograde blood flow for 10 minutes, after which flow-limited reperfusion (30-60% of the coronary flow before ischemia) was performed. The dogs were divided according to the agent administered before ischemia into the following three groups: saline (group S, n = 11); lidocaine (group L, n = 8, 0.07 mg/kg/min by intravenous drip infusion following 2 mg/kg intravenous injection); and diltiazem (group D, n = 9, 0.02 mg/kg/min by intravenous drip infusion. There were no significant differences among the three groups in the incidence of ventricular tachyarrhythmia, which occurred as ventricular tachycardia (VT) or ventricular fibrillation (VF). In each group, the occurrence of VT was frequently preceded by delayed potential which was initiated after reperfusion, with depressed conduction in the epicardium, suggesting reentry (82%, 96%, and 87%, not significant). The determining factors for VT with degeneration into VF were long duration of VT in groups S and L (VT with degeneration into VF vs VT without, 1.2 +/- 0.2 seconds vs 0.6 +/- 0.1 seconds, P < .05, in group S and 11.6 +/- 2.5 seconds vs 2.2 +/- 0.4 seconds, P < .05, in group L), and decrease in average R-R interval during VT in groups L and D (195 +/- 8 ms vs 313 +/- 17 ms, P< .01, in group L and 201 +/- 11 ms vs 327 +/- 28 ms, P< 0.01, in group D). In addition, occurrence of epicardial electrophysiologic activity with reduced time from onset of the QRS complex in the surface electrocardiogram to the onset of the activity during VT preceded VF in group L (VT with degeneration into VF vs VT without, 130.0 +/- 15.1 ms vs 185.8 +/- 21.4 ms, P < .05), while that with prolongation of the time had this effect in group D (116.0 +/- 15.7 ms vs 69.0 +/- 10.7 ms, P < .05). It is concluded that, even when partial reperfusion is applied, neither lidocaine nor diltiazem suppresses VT because neither drug decreases delayed potential acting as a triggering factor or suppresses VF, since the alteration of the epicardial conductivity during VT can change the VT circuit to a smaller one.

Animals↗

Expression of glucose transporters in rat brain following transient focal ischemic injury.

We have investigated the serial changes in the transcription and translation of the rat glucose transporter (GLUT) 1 and 3 genes after 3 h of middle cerebral artery (MCA) occlusion followed by reperfusion. Northern blot analysis and in situ hybridization study were performed to determine the chronological change and regional expression. In the ipsilateral anterior cerebral artery (ACA) cortex, GLUT1 mRNA expression was increased at 12 h (11.6-fold) of reperfusion, and its expression was detected not only in vascular endothelial cells but also in neurons. At 48 h of reperfusion, GLUT3 mRNA expression was increased in the ipsilateral ACA (8.6-fold) and in the contralateral MCA cortex (9.1-fold). Immunohistochemical study failed to show GLUT1 protein synthesis in neurons in the ipsilateral ACA cortex. The immunoreactivity of GLUT3 protein was increased in neurons in ipsilateral ACA cortex and contralateral MCA cortex. Our results suggest that the expression of GLUT1 and GLUT3 is controlled differently after transient focal ischemic conditions. Furthermore, the postischemic localizations of both GLUT1 and GLUT3 expressions may be altered from the normal physiological expression pattern, which may be of importance in investigating postischemic cell function.

Animals↗

Regeneration across a partial defect in rat sciatic nerve encased in a silicone chamber.

Forty-four rat sciatic nerves with partial defects were repaired with a silicone chamber. Each partial defect was created by resecting a 10 mm segment from the tibial fascicle leaving the peroneal fascicle intact. The proximal and the distal stumps of the tibial fascicle together with the intact peroneal fascicle were encased in a single silicone chamber. After seven days a fibrin matrix had surrounded the peroneal fascicle and spanned the defect between the tibial stumps. This matrix was later invaded by non-neuronal cells and regenerating axons. Non-myelinated nerve fibres had almost regenerated across the defect by 16 days. The tetanic force of the gastrocnemius muscle 120 days after repair showed 80% recovery, which was no different from that of partial defects repaired with conventional nerve grafts. The results suggest that the silicone chamber technique could be applicable to the treatment of partially transected nerve trunks.

Animals↗

Differentiation of embolic and thrombotic middle cerebral artery occlusion using ultrasonic carotid flow velocity analysis.

The purpose of this study was to determine the value of Duplex ultrasound of the carotid arteries in the differentiation of embolic from thrombotic middle cerebral artery (MCA) occlusion. We report here the results of carotid Duplex ultrasound study from 164 patients with acute ischemic stroke. Flow velocity and diameter were measured in bilateral common carotid arteries (CCA). The end-diastolic flow velocity (Ved) and the pulsatility index (PI) were calculated from Doppler waves. The PI is an index of peripheral vascular resistance. We compared the relationship between percent carotid stenosis and percent decrease in Ved. The patients studied could be classified into three groups using ultrasound parameters. Group I was characterized by > 30% decrease in Ved and < 80% carotid stenosis, group II by < 30% decrease in Ved and < 80% carotid stenosis, and group III by > 30% decrease in Ved and > 80% carotid stenosis. All 23 patients in group I had embolic MCA stem occlusion. 28 out of 115 patients in group II had thrombotic MCA stem occlusions. All 26 patients in group III had internal carotid artery occlusion or severe stenosis. Ved was markedly reduced in group I and group III compared to group II (p < 0.01). PI in the affected artery was increased in groups I and III (p < 0.01). Embolic occlusion was characterized by > 30% decrease in Ved in the absence of > 80% carotid stenosis, and an increase in PI. The results indicate that these two conditions can be differentiated using Duplex ultrasound in carotid arteries.

Acute Disease↗

Differentiation between human immunodeficiency virus type 1 (HIV-1) and HIV-2 isolates by nonradioisotopic reverse transcriptase-typing assay.

We tested whether human immunodeficiency virus type 1 (HIV-1) could be differentiated from HIV-2 by a reverse transcriptase (RT)-typing assay that measured the reduction of enzyme activity owing to specific antibody. RT-inhibiting antibody was examined for HIV type specificity by a new nonradioisotopic RT assay. Antibodies from four rabbits immunized with recombinant HIV-1 RT and from 23 HIV-1-seropositive individuals all specifically inhibited the enzyme activities of two HIV-1 strains (LAV-1 and GH-3), three zidovudine-resistant HIV-1 mutants, and a recombinant HIV-1 RT. However, none of these antisera affected the activities of six HIV-2 strains (GH-1, GH-2, GH-4, GH-5, GH-6, LAV-2ROD), Rous-associated virus type 2, and DNA polymerase I from Escherichia coli. In contrast, HIV-2 antibody from a rabbit immunized with disrupted GH-1 virions blocked the enzyme activities of the six HIV-2 strains but not those of the three HIV-1 strains, Rous-associated virus type 2, or DNA polymerase I. These results indicate that the antigenic domains of HIV-1 and HIV-2 RTs recognized by their inhibiting antibodies are distinct from each other and are highly conserved. Clinical HIV isolates from 18 HIV-1-seropositive individuals and 3 HIV-2-seropositive Ghanaian individuals were identified as HIV-1 and HIV-2, respectively, by the nonradioisotopic RT-typing assay.

Antibodies, Viral↗

Compliance with antiplatelet therapy in patients with ischemic cerebrovascular disease. Assessment by platelet aggregation testing.

BACKGROUND AND PURPOSE: Antiplatelet therapy is currently one of the methods for preventing transient ischemic attacks and cerebral thrombosis. Because antiplatelet agents are generally administered on a long-term basis, patient compliance is an important factor. The purpose of this study was to determine the compliance of patients during antiplatelet therapy by testing platelet aggregation. METHODS: To establish the conditions for measuring platelet aggregation, the platelet aggregation test was performed in patients taking 81 mg/d aspirin or 200 mg/d ticlopidine at the following final concentrations of aggregation-inducing agents: 0.5, 1, 2, and 4 mumol/L ADP and 0.5 and 2 micrograms/mL collagen. The optimum measurement conditions for assessing patient compliance were determined. Under the conditions determined in the first study, platelet aggregation was assessed, and the effects of treatment were studied in 159 outpatients and 79 inpatients undergoing antiplatelet therapy. If the antiplatelet effect was insufficient, compliance was checked by interview. RESULTS: The agents used and the final concentrations found to be optimum for assessing platelet aggregation were 2 micrograms/mL collagen for patients taking aspirin 81 mg/day and 2 mumol/L ADP for patients taking ticlopidine 200 mg/d. In 17 (10%) of the 159 outpatients, platelet aggregation was not adequately reduced because of noncompliance with their antiplatelet therapy. CONCLUSIONS: This study indicated that monitoring of compliance is important for outpatients on antiplatelet therapy. It is best if platelet aggregation can be checked, but when this is impossible it is necessary to assess compliance periodically and provide patient guidance.

Adenosine Diphosphate↗

Regulation of liver regeneration by interleukin-2 and its inhibitors: cyclosporine A and FK 506.

Several investigations have been suggesting that lymphocytes can be responsible for growth regulation of liver. The interleukin-2 (IL-2) production by spleen cells was noted to be increased 2 days after resection of 70% of the volume of the liver in C3H/He mice. The effects of IL-2 production and its antagonists: cyclosporine A (CsA) and FK506 on liver regeneration were thus studied by measuring in vivo incorporation of Bromodeoxyuridine (BrdU). By intraperitoneal injection of IL-2 5 times every 8 h after hepatectomy. BrdU labeling indices at 36 h after the operation were suppressed in a dose-dependent manner. On the other hand, treatment with CsA and FK506, which inhibit IL-2 production, increased the mitotic indices of the regenerating livers. Serum levels of aminotransferases were not affected by FK506 at a dose sufficient for the mitotic stimulation. Based on these results, CsA and FK506 would appear to stimulate liver cell proliferation by suppressing IL-2 production and inhibiting of NK cell activity.

Animals↗

[A stick type filter unit for prevention of biohazard in a research laboratory].

It is important to prevent unexpected laboratory infections in a biosafety area. It is recommended that extreme caution should be used when handling needles and syringes to avoid autoinoculation, and that needles and syringes should be used only when there is no alternative. To remove cells and cell debris, a disk-type microfilter unit, which is recommended using a needle, has been used for filtrating supernatant from HIV-1-infected cell cultures. We compared a stick-type microfilter unit, which can be used without a needle, with a disk-type one for their safety and recovery of human immunodeficiency virus particle after filtration. To confirm the right of our comparison, we observed the filter electron microscopically for the virus particles and virus suspensions were carried out and discussed. In conclusion, the stick-type filter should be improved, since the filter unit is inferior to the disk-type filter unit in purification of the virus, but for the safety is superior to the disk-type.

Acquired Immunodeficiency Syndrome↗

[Non-radioisotopic reverse transcriptase assay using biotin-11-deoxyuridine-triphosphate and a primer-immobilized microtiter plate: application for detection and identification of isolated retroviruses from HIV-1-seropositive hemophiliac patients].

Non-radioisotopic reverse transcriptase assay (Non-RTA) was successfully applied for detection and identification of the retroviruses isolated from peripheral mononuclear cells from eight HIV-1-seropositive hemophiliac patients. Of 40 samples, 36 (90%) were consistent in detection between Non-RI and RI RTA. Four samples which showed RT activities slightly above the cutoff level of RI RTA were not detected by Non-RI RTA. Non-specific RT-inhibitors in the culture supernatant decreased the sensitivity of Non-RI RTA more significantly than that of RI RTA. It was demonstrated that higher concentrations (> 20%) of fetal calf serum in RPMI-1640 culture medium inhibited the hybridization of poly rA template with immobilized primer, resulting in reducing the sensitivity of Non-RI RTA. Then we identified the isolated retroviruses using specific RT-inhibiting (RTI) antibodies against HIV-1 and HIV-2. HIV-1 RTI antibody specifically inhibited RTs of isolated retroviruses and HIV-1 strain, LAV-1, but not HIV-2 and Rous-associated virus 2 (RVA-2) RT. Conversely, HIV-2 RTI antibody specifically inhibited HIV-2 RT, but not HIV-1 and RAV-2 RT. These findings agreed with previously reported results showing the type-specificity of HIV-1 and -2 RTI antibodies, and suggest the possibility that isolated retroviruses could be identified by these antibodies.

Biotin↗

Inhibition of liver regeneration in mice following extended hepatectomy by transfusion of lymphokine activated killer cells.

Lymphokine activated killer (LAK) cells can destroy not only tumor cells but also syngeneic liver cells. In this study, the effects of passive transfer of LAK cells on liver regeneration were examined by the 3H-thymidine uptake and bromodeoxyuridine (BrdU) labeling methods after resection of 70% of the volume of the liver. LAK cells were infused 12h after hepatectomy and the effects on regeneration of liver cells were examined 36 h later. The transfusion of LAK cells induced significant inhibition of liver regeneration at a dose of 5-10 x 10(7) cells. Neuraminidase treatment of lymphocytes is desirable to enhance the selective entrapment of LAK cells into the liver. When LAK cells were treated with neuraminidase (0.5 units/ml), and transfused into hepatectomized mice, more potent suppression of liver regeneration was induced in comparison with the same dose of LAK cells. The intraperitoneal injection of recombinant interleukin 2 (rIL-2) after partial hepatectomy also inhibited the regeneration of remnant liver. From these results, lymphocytes such as LAK cells appear to regulate liver regeneration.

Animals↗

Distant metastasis of hepatocellular carcinoma after successful treatment of the primary lesion.

Recent advances in both diagnosis and treatment of hepatocellular carcinoma (HCC) have improved the prognosis and changed the clinical significance of the subsequently increasing distant metastases. Of 163 patients with HCC, 76 (47%) were treated successfully. The cumulative recurrence rate in these patients was 65% after 3 years, and 82% after 5 years. Six patients with HCC in whom distant metastases were detected after successful treatment of the primary lesion, are reported. Two patients underwent curative surgical resection, and four cases were treated medically, resulting in a 31.9 to 94.3% reduction in tumor size in the CT scan image. Distant metastases without intrahepatic recurrence were diagnosed 10 to 46 months after the treatment of the primary lesions. The sites of the metastases included bone 3; lung 2; and adrenal gland 1. Distant metastases found after successful treatment of the primary lesions are of great clinical significance for the treatment of HCC.

Adrenal Gland Neoplasms↗

[A case of giant hepatocellular carcinoma effectively treated by UFT].

An 84-year-old woman who suffered from heart failure was admitted to our hospital in July 1991. We found a hepatocellular carcinoma, of about 9 cm in diameter in her right liver lobe. The patient could not be operated on, TAE and PEIT, so she has been administered UFT (300 mg/day) orally every day. After seven months, observing the patient by means of computerized tomography, we noticed that the tumor had decreased in size until only a small cyst was left. PIVKA-II reached the normal range (under 0.063 AU/ml) from its previous level (42.940 AU/ml). She has maintained a good state of health for about two years now. This is considered a very rare case in which chemotherapy proved to be completely effective, and the patient has survived for a long time afterwards.

Aged↗