Biomedical subjects

T Nishimura

Publications and source records attributed to T Nishimura.

At least 667 records · Page 37Linked to original sources

PubMed1994

Split dose iodine-123-IMP SPECT: sequential quantitative regional cerebral blood flow change with pharmacological intervention.

UNLABELLED: At least two quantitative rCBF measurements are needed to evaluate rCBF changes with pharmacological intervention. We have developed the split dose 123I-IMP SPECT method, which enables measurement of rCBF to be repeated in a short time. METHODS: Thirty-one cerebrovascular disease patients were investigated to assess reproducibility and vasoreactivity to acetazolamide. During 44-min dynamic SPECT imaging, 123I-IMP injection and respective arterial sampling were performed twice at an interval of about 25 min. The rCBF values were calculated using a microsphere model in which the washout of 123I-IMP from the brain can be negligible in the first several minutes after injection. For the second rCBF measurement, the remaining activity due to the first 123I-IMP injection was estimated and subtracted from the total brain activity. RESULTS: In ten patients, two consecutive resting mean rCBF values in the MCA territory (CBF1 and CBF2) had good correlation (CBF1 = 47.4 +/- 4.0 (ml/min/100 ml: mean +/- s.d.), CBF2 = 45.2 +/- 8.2, CBF2 = 0.900*CBF1 + 2.9, r = 0.915). In 11 patients with occlusive lesions in the unilateral ICA system, mean rCBF in the MCA territory was increased by only 27.7% +/- 14.0% in the affected side by a 1-g intravenous acetazolamide injection, while 44.5% +/- 12.3% increase was found in the nonaffected side. In 10 patients without a major arterial lesion, a 49.7% +/- 17.0% increase of rCBF was demonstrated. CONCLUSIONS: This split dose method 123I-IMP SPECT can be useful to estimate vascular reserve.

Acetazolamide↗

PubMed1994

[Expression of GPI-anchor proteins during the differentiation from hematopoietic progenitors in patients with paroxysmal nocturnal hemoglobinuria].

We studied the expression of HRF20, one of the GPI-anchor proteins, on the hematopoietic progenitors and their progeny cells grown in cultures with bone marrow cells from patients with paroxysmal nocturnal hemoglobinuria (PNH). PNH bone marrow cells were sorted by fluorescence-activated cell sorter with anti-HRF20 monoclonal antibody and then cultured in methylcellulose. Every CFU-GM colonies and BFU-E bursts formed from the HRF20-negative fraction were HRF20-negative. On the other hand, there were HRF20-positive colonies and bursts as well as HRF20-negative ones in cultures with bone marrow cells from the HRF20-positive fraction. The results suggested that abnormal events can occur during the several steps of differentiation form PNH hematopoietic stem cells.

Bone Marrow Cells↗

PubMed1994

Kinetics of a putative hypoxic tissue marker, technetium-99m-nitroimidazole (BMS181321), in normoxic, hypoxic, ischemic and stunned myocardium.

UNLABELLED: This study focused on the kinetics of the newly developed 99mTc-nitroimidazole, propyleneamine oxime-1,2-nitroimidazole (BMS181321) in the different setting of myocardial perfusion states and oxygenation levels, and compared the kinetics of BMS181321 with those of other technetium analogues. METHODS: The kinetics of BMS181321 were evaluated in isolated perfused rat hearts. Technetium-99m-hexamethylpropyleneamine oxime (HMPAO) and a non-nitroimidazole-containing analogue of BMS181321 (6-methyl propyleneamine oxime; PAO-6-Me) were used to compare their kinetics with those of BMS181321. RESULTS: BMS181321 cleared quickly from normoxic hearts and the retention in the myocardium 10 min after injection was 0.84% +/- 0.04% ID/g wet wt (mean +/- s.e.m.). In contrast, BMS181321 was retained after reperfusion when it was injected before ischemia; the uptake in the myocardium 10 min after reperfusion was significantly greater than in controls (23.9% +/- 3.9% ID/g wt, p < 0.05). CONCLUSIONS: These results indicate that 99mTc-BMS181321 is well trapped in ischemic myocardium and moderately trapped in hypoxic myocardium, but washed out quickly in stunned myocardium. The residence time influences the amount retained.

Animals↗

PubMed1994

[Abnormal evoked EMG and blink reflex responses in patients with hemifacial spasm (HFS)].

Abnormal evoked EMG and blink reflex responses have been observed on the affected side in patients with HFS. These characteristic responses were used as methods of preoperative differential diagnosis, and the disappearance of these abnormal responses during intraoperative monitoring was assessed as confirmation of nerve decompression. The subjects were 30 patients with a diagnosis of HFS. Three responses were evaluated: 1) the orbicularis oris muscle (OR) response to stimulation of the orbicularis oculi muscle branch (OB), OB-->OR; 2) the orbicularis oculi muscle (OC) response to stimulation of the marginal mandibular branch (MB), MB-->OC; and 3) the (OR) response to stimulation of the supraorbital nerve (SO), SO-->OR. The facial nerve in the root exit zone was compressed by a vessel in all 21 patients diagnosed as typical HFS who had abnormal responses, and OB-->OR was always detected. The MB-->OC and SO-->OR detection rates were low (50% and 25%, respectively) when the interval since the onset of HFS was less than 3 years, but increased to 78% and 67%, respectively, when it was 3 to 5 years, and all three abnormal responses were always detected when the interval was more than 5 years. In 17 of the patients these responses began to change and eventually disappeared before decompression of the facial nerve, and in 2 patients they persisted even after decompression. Abnormal responses disappeared at the time of decompression in only 2 patients, and their HFS was completely cured postoperatively. These findings confirmed that disappearance of abnormal responses is not a very useful guide for facial nerve decompression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1994

Enzymatic characterization of cathepsin D in rabbit brains with experimental neurofibrillary changes.

Aluminium salt was injected intracerebrally into rabbits resulting in experimental neurofibrillary change (ENFC) formation as a model of Alzheimer neurofibrillary change. Cathepsin D was purified from the experimental and the control rabbit brains and the enzymatic properties were further investigated. The specific activity of cathepsin D in the tissue homogenate from the ENFC brains was 27% higher than that of the control, reflecting the induction of the enzyme by aluminium injection. The apparent Km values of the control and ENFC enzymes were calculated to be 26.3 microM, 29.3 microM, respectively, when assayed with bovine hemoglobin as substrate. The heat inactivation proceeded linearly with time for the control enzyme but biphasically for the ENFC enzyme, suggesting that less-reactive type of cathepsin D was induced by aluminium injection. Other properties such as molecular weight, optimum pH and amino acid composition were similar to each other.

Aluminum Chloride↗

PubMed1994

[Myocardial washout of 99mTc-hexakis-2-methoxy isobutyl isonitrile (99mTc-MIBI) at exercise myocardial scintigraphy in patients with ischemic heart disease].

Myocardial washout of the new myocardial perfusion imaging agent, 99mTc-hexakis-2-methoxy isobutyl isonitrile (99mTc-MIBI) was studied in 23 patients with coronary artery disease. These patients were divided into three groups; 8 patients with effort angina pectoris (AP group), 6 with myocardial infarction who had reversible defect (MI-RD (+) group) and 9 with myocardial infarction who had not reversible defect (MI-RD (-) group). Regional radioactivities were determined with postexercise 1- and 3-hour myocardial planar images. In AP group, 99mTc-MIBI washout rate in ischemic area was smaller than in normal area (3.8 +/- 7.5% vs. 8.3 +/- 5.6%, p < 0.05), however, in the remaining two groups, there were no difference in washout between normal and infarct areas. Defect/normal ratios from postexercise 1 hour to 3 hours were slightly increased in AP and MI-RD (+) groups. Our results indicate that 99mTc-MIBI showed slight and incomplete myocardial redistribution in ischemic areas. These data showed to be considered in the interpretation of 99mTc-MIBI myocardial imaging.

Aged↗

PubMed1994

[MECHOP-BM chemotherapy in the treatment of non Hodgkin's lymphoma].

Twenty patients with previously untreated advanced aggressive or relapsed or refractory non-Hodgkin's lymphoma were treated with the MECHOP-BM regimen (MCNU, etoposide, cyclophosphamide, adriamycin, vincristine, prednisolone, bleomycin and methotrexate). Of the 18 patients treated with the MECHOP-BM, the response rate was 78% and complete response (CR) was attained in 33%. Among these CR patients, one patient relapsed, but the other patients continued to show CR (59-243 days, medium 178 days). The most serious toxicity attributed to MECHOP-BM therapy was leukopenia. The mean white blood cell count dropped to 1,300/microliters, and only therapy could be useful in the treatment for patients with untreated aggressive and advanced stage of non-Hodgkin's lymphoma as well as salvage therapy of relapsed cases.

Adolescent↗

PubMed1994

[Lung 3H-thymidine incorporation in monocrotaline (MCT)-treated rats--role of platelet-activating factor (PAF)].

Monocrotaline (MCT) causes chronic pulmonary hypertension associated with pulmonary vascular thickening in rats. Since components of the pulmonary vascular thickening are reflected in increased DNA synthesis in medial smooth muscle cells, and since platelet-activating factor (PAF) has been reported to contribute to the pulmonary hypertension induced by MCT, we examined the effect of WEB 2170, a specific PAF receptor blocker, on MCT-induced pulmonary vascular thickening and in vitro 3H-thymidine incorporation into lung tissue, as an index of stimulation of cell proliferation. In MCT-treated rats, pulmonary hypertension, right ventricular hypertrophy, and pulmonary vascular thickening developed at 3 weeks after injection. Also, in MCT-treated rat lung tissue, there was a significant increase in the in vitro 3H-thymidine incorporation rate. In WEB 2170-treated MCT rats, these changes were significantly less severe than those observed in rats receiving MCT alone. We conclude that PAF plays a role in the inflammatory process that contributes to the development of pulmonary hypertension and vascular remodeling associated with increased lung cell proliferation in MCT-treated rats.

Animals↗

PubMed1994

[Clinical treatment of urinary tract stones with Alexandrite laser].

Clinical treatment of urolithiasis with Alexandrite-laser which is a solid pulse laser system developed in Switzerland is reported. Two cases of renal stones, 3 cases of vesical stones, and 35 renal units in 34 cases of ureteral stones were treated. The approach to the aimed stone was, percutaneous to the renal stones, and transurethral to the vesical and ureteral stones. The clinical success rate was 92.5% (37/40), when we defined success as the endoscopically observed fragmentation. The uric acid stone in the bladder was not disintegrated even when the plasma occurred, but the ureteral uric acid stone was easily fragmented. The difference was thought to be attributed to the condition of the surface. The Alexandrite-laser system generates a 750 nm wavelength, and this wavelength is neither absorbed in water nor hemoglobin, so is thought to be harmless to the tissue. Actually, if misirradiation to the ureteral mucosa during lithotripsy was done, neither plasma formation nor perforation occurred. In conclusion, the Alexandrite-laser is thought to be safe and effective equipment for the treatment of urolithiasis.

Adult↗

PubMed1994

Effect of actarit on type II collagen-induced arthritis in mice.

The effect of actarit (MS-932, CAS 18699-02-0), an antirheumatic drug, on type II collagen (CII)-induced arthritis in DBA/1J mice was studied. Mice were immunized twice with bovine CII, actarit being given orally once a day for 35 days after the 1st immunization. Clinical assessment showed that actarit had no effect on the incidence or day of onset of arthritis but that it lowered the arthritis score dose-dependently. Radiography showed that actarit reduced new bone formation in the limbs, and a histopathologic examination showed that it reduced synovitis, erosion of cartilage and bone destruction. Actarit suppressed the delayed-type mouse ear skin reaction to CII but had no effect on the level of serum anti-CII antibodies. These results suggest that actarit inhibits the development of CII-induced arthritis in mice by suppressing delayed-type hypersensitivity to CII.

Animals↗

PubMed1994

[A case of lung cancer combined with ocular myopathy and idiopathic thrombocytopenic purpura which was presumed to be caused by heart catheterization].

A 61-year-old patient was admitted to our hospital because of a chest abnormal shadow. He was suffered from ocular myopathy for more than 4 years. A lab data on the admission showed only a slight thrombocytopenia. After the unilateral pulmonary arterial occlusion test for the preoperative evaluation of thoracotomy, the hemorrhagic tendency was appeared. A detailed examination proved idiopathic thrombocytopenic purpura which was presumed to be caused by the heart catheterization. We employed high-dose intravenous gamma-globulin infusion and concentrated platelet transfusion for 5 days for preventing hemorrhagic complications during the thoracotomy. The partial resection was undergone for the left upper lobe tumor, which was proved as large cell carcinoma. The postoperative hemorrhage was well controlled. We conclude that the high-dose intravenous gamma-globulin infusion and/or concentrated platelets transfusion should be positively employed for the patients with even slight thrombocytopenic purpura.

Carcinoma, Non-Small-Cell Lung↗

PubMed1994

[A case of atypical presenile dementia].

Kosaka (1993) reviewed 16 cases of slowly progressive presenile cortical dementia thought to be a clinicopathological entity with pathological features characterized by circumscribed lobar atrophy, diffuse neurofibrillary tangles, and calcification of the Fahr type, however, the clilical features of this new entity are not known in the description of detail. We report a patient with atypical presenile dementia which appeared to be consistant with that entity, together with the results of a comprehensive neuropsychological and neuroradiological examination. The patient was a 65-year-old right-handed housewife. At about 58 years of age, she started to lose spontaneity and develop a mild memory disturbance. At age 61 she transiently, experienced hallucinations and delusions. During the subsequent 8 years there was a very slight decline in global intellectual efficiency. In addition, she showed slow but definite progression of language disturbances characterized by anomia and loss of ability to grasp the meaning of words, particularly abstract nouns. She performed poorly on tasks with good sensitivity for detecting frontal lobe dysfunction, such as the Wisconsin Card Sorting Test and the hand sequence test. All other cognitive functions appeared to be relatively well preserved, however moderate dyscalculia was present. There was no socially inappropriate or stereotyped behavior, but the patient lost insight into her disease. The patient's activities of daily living on the ward were self-maintained. An EEG was normal. CT and MRI scans showed circumscribed bilateral fronto-temporal atrophy and bilateral mineralization in the basal ganglia and cerebellar white matter.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1994

[Pharmacokinetic and clinical evaluations of fluconazole in pediatric patients].

Fluconazole (FLCZ) is a novel antifungal agent and available both in oral and intravenous forms. It is characterized by a long plasma half-life and a good absorbability into tissues. Because of these, it is expected to be used safety and to exhibit good clinical efficacy in the deep seated mycosis of children. We evaluated the efficacy of FLCZ given orally or intravenously to 6 patients. Pathogenic fungi isolated from all patients were Candida, and diagnosises made were candidemia in 3 cases, gastro-intestinal candidiasis in 2 and skin candidiasis. The clinical efficacies of FLCZ in 5 cases were excellent in 2 cases of gastro-intestinal candidiasis and poor in 3 cases of candidemia. None of the patients reported any side effect. In clinical laboratory tests, no abnormalities that were judged to be related to FLCZ were noted. In the study, clinical efficacy was shown to be poor in candidemia, because these cases had severe underlying diseases and the proper therapy was started too late. Thus earlier diagnosis and earlier treatment seem to be important for FLCZ to exhibit good clinical efficacy in the treatment of deep-seated mycosis.

Administration, Oral↗

PubMed1994

[A comparative clinical study on the treatment of head and neck tumors by adjuvant chemotherapy with HCFU--Second Study by Kinki Head and Neck Tumor Study Group].

In the first study by the "Kinki Head and Neck Tumor Study Group," we performed a comparative study to investigate intergroup difference between a control group consisting of patients given radical treatment only, and a HCFU group consisting of patients receiving long-term administration of HCFU after radical treatment. We earlier reported that subsequent observations by stratification revealed a favorable tendency in the cumulative disease-free rate in Stage II and Stage III patients in the HCFU group. In the second study, the same methods of treatment as in the first study were compared in a prospective control study. No differences were found between the two groups in Stage II patients. In Stage III patients, however, the disease-free rate tended to increase significantly in the HCFU group as in the first study.

Adult↗

PubMed1994

Carbon dioxide reactivity by consecutive technetium-99m-HMPAO SPECT in patients with a chronically obstructed major cerebral artery.

UNLABELLED: In the management of major cerebral artery obstruction, cerebral perfusion reserve is key to introducing cerebral revascularization surgery. The purpose of this study was to evaluate the feasibility of assessing cerebral perfusion reserve by consecutive 99mTc-hexamethyl-propyleneamine oxime (99mTc-HMPAO) SPECT with 5% carbon dioxide (CO2) inhalation. METHODS: The CO2 inhalation and consecutive 99mTc-HMPAO SPECT study was performed on 30 chronic ischemic cerebrovascular disease patients with unilateral major cerebral artery obstruction and on 27 patients without. CO2 reactivity was expressed as the percent increase of 99mTc-HMPAO accumulation from the baseline (%Change) and as a constant k' that was the ratio of 99mTc-HMPAO accumulation per 1 mmHg change of end-tidal CO2 tension by exponential curve fitting. RESULTS: The mean %Change and k' in the middle cerebral artery (MCA) territory on the side without an obstructive lesion or in the cerebellum ranged from 10.0% to 11.1% and from 0.98% to 1.13% per mmHg, respectively. In the MCA territory, an obstructive lesion was noted in 5.9% versus 0.54% per mmHg in the contralateral MCA territory (p < 0.01). Eleven of 30 patients with major cerebral artery obstruction revealed significant asymmetry in the k' value between bilateral MCA territories. CONCLUSION: The results showed compromised cerebral perfusion reserve in the obstructed major cerebral artery territory. The present method was proven clinically useful for evaluating cerebral perfusion reserve in patients with unilateral major cerebral artery obstruction.

Adult↗

PubMed1994

[Simultaneous assessment of exercise-induced abnormalities in myocardial perfusion and regional wall motion by using 99mTc-tetrofosmin].

To clarify the usefulness of the combined assessment of exercise (EX)-induced abnormalities in myocardial perfusion and regional wall motion for detecting coronary artery disease (CAD), we carried out first-pass radionuclide angiography and myocardial perfusion imaging during EX and at rest by 99mTc-tetrofosmin. Twenty-four patients with angiographically proven CAD, 9 (Gp A) with single and 15 (Gp B) with multivessel disease, were studied. The sensitivity for the detection of CAD was 78% of Gp A, 73% of Gp B in planar image and 78%, 87% in SPECT image, respectively. When left ventricular ejection fraction and regional ejection fraction (rEF) were combined with the result of myocardial perfusion, sensitivity increased up to 89% of Gp A, 100% of Gp B. Diagnostic accuracy of LAD, LCX and RCA was 79%, 88% and 83%, respectively. Regional EF in ischemic areas decreased during EX in both Gps, particularly in Gp B. Regional EF in relatively normal perfusion areas did not significantly change in Gp A, but decreased in Gp B. These results suggest that 99mTc-tetrofosmin contributes to the improvement of sensitivity for CAD by combined assessment of EX-induced wall motion and myocardial perfusion abnormalities.

Aged↗

PubMed1993

Molecular cloning of a novel putative G protein-coupled receptor (GPCR21) which is expressed predominantly in mouse central nervous system.

A novel cDNA clone encoding a putative G protein-coupled receptor (named GPCR21) was isolated from a mouse brain cDNA library along with its homologue, GPCR01 (the mouse counterpart of previously reported rat receptor R334 [(1991) FEBS Lett. 292, 243-248]) by the polymerase chain reaction using degenerate oligonucleotide primers. Northern blotting and reverse transcription-polymerase chain reaction analyses showed predominant expression of these two receptors in the central nervous system. In situ hybridization analysis revealed their prominent expression in the limbic system and further demonstrated the differential distribution of their mRNAs in mouse brain. Although the ligands for these receptors are yet to be identified, the significant sequence homology between these receptors suggests that they constitute a new receptor subfamily and they possibly represent different receptor subtypes for an unknown neurotransmitter.

Amino Acid Sequence↗

PubMed1993

[Detectability of diagonal branch disease with other branch lesions by 201TlCl exercised myocardial scintigraphy].

The detectability of coronary diagonal (Dx) branch disease in 24 patients (16 with myocardial infarction, 8 with angina pectoris; mean age of 56) with other branch (left anterior descending branch [LAD], left circumferential branch [LCX], or right coronary artery [RCA]) diseases was reviewed with 201TlCl exercised myocardial planar and SPECT images. In Dx branch disease with LAD #7 lesion (n = 10), Dx perfusion abnormality was detected in planar and SPECT images in 3 (30%) and 8 patients (80%), respectively. In Dx branch disease with LCX lesion (n = 7), Dx perfusion abnormality was detected in planar and SPECT images in 3 (43%) and 4 patients (57%), respectively. In Dx branch disease with RCA lesion (n = 7), Dx perfusion abnormality was detected in only 1 (14%) and 2 patients (29%), respectively. In conclusion, SPECT is a useful modality for detecting Dx branch disease, but it is sometimes hard to detect Dx branch disease with LCX and RCA lesions.

Coronary Disease↗