Biomedical subjects

N Ono

Publications and source records attributed to N Ono.

At least 127 records · Page 7Linked to original sources

PubMed1994

Value of thallium-201 early reinjection for assessment of myocardial viability.

To assess the efficacy of early reinjection for predicting post intervention improvement in thallium-201 (T1) uptake and regional wall motion, we reinjected a small dose of T1 following post-stress imaging and obtained reinjection early images (10 min after early reinjection) and reinjection delayed images (3 hr afterwards) in 40 patients who were referred to us for revascularization (group I). Twenty-nine patients in group I also underwent conventional stress-redistribution T1 scintigraphy (group II). Conventional stress-redistribution T1 scintigraphy was repeated after intervention. Contrast left ventriculography was performed before and after intervention and changes in regional wall motion were assessed in 22 of 40 patients. In group I, the predictive value for improvement and no improvement (the accuracy) of reinjection early images in perfusion was 83%, while that of reinjection delayed images was 91%. Furthermore, the accuracy of reinjection early images in regional wall motion was 80%, while it was 91% for reinjection delayed images. In group II, the accuracy in perfusion was 78% and the value in regional wall motion was 70%. Both accuracy in perfusion and in regional wall motion obtained from reinjection delayed images were significantly higher than the values in group II (p < 0.05). These data suggest that early reinjection is useful for predicting postintervention thallium uptake and regional wall motion.

Aged↗

PubMed1994

A clinical feature of myocardial stunning associated with acute myocardial infarction.

We report a case of myocardial stunning after acute myocardial infarction. In the hyperacute phase of myocardial infarction, the patient's coronary arteries showed normal features on coronary angiography during extensive ST-segment elevation observed on a standard 12-lead electrocardiogram and extensive akinesis observed on a left ventriculogram. Thallium-201 emission computed tomography revealed extensive perfusion abnormality. In the chronic phase, the perfusion abnormality was markedly improved. However, the electrocardiogram demonstrated poor R wave progression, and the left ventriculography revealed slight hypokinesis in the anterolateral wall. The acetylcholine provocation test disclosed coronary vasospasm of the left anterior descending coronary artery. About six months thereafter, left ventricular wall motion became completely normal and no poor R wave progression was observed on the electrocardiogram. The findings in this case indicate that myocardial stunning resulted from brief but sever ischemia due to vasospasm which led to cardiogenic shock, and that the recovery of findings for thallium-201 perfusion might be followed by those of electrocardiography and left ventriculography in the stunned myocardium.

Acetylcholine↗

PubMed1994

Factors affecting functional prognosis in survivors of primary central nervous system germinal tumors.

We evaluated 79 patients of whom 62 survived treatment for intracranial germinal tumors between 1964 and 1992. The survivors were assessed for their Karnofsky scores and intellectual and reproductive functions to verify factors associated with better prognosis. Thirty-one tumors were pineal, 17 were suprasellar, and ten were in the basal ganglia. These included 50 germinomas, five teratomas, and seven tumors of extra-embryonic origin producing alpha-fetoprotein or human chorionic gonadotropin. Although patients with germinoma or benign teratoma had better Kaplan-Meier survival rates than those with extra-embryonic origin tumors, the mean Karnofsky scores of the survivors did not differ significantly among the three histologic groups. On the other hand, although survival rates did not differ significantly among different tumor site groups, the mean Karnofsky score of the pineal group was higher than that of the suprasellar or basal ganglia group. Intellectual and reproductive functions were severely affected in the basal ganglia and suprasellar tumor groups, respectively. The Karnofsky score of survivors treated after 1977 was higher than for those treated before 1977. The score of patients who received less than 55 Gy irradiation was better than those who received more than 55 Gy. No patient who received less than 45 Gy developed a recurrence, suggesting that a lower dose may suffice for pure germinomas. Tumors of extra-embryonic origin, however, should be treated with combined chemotherapy to minimize subsequent irradiation. Factors affecting survivors' capabilities are discussed.

Adolescent↗

PubMed1994

An immunohistochemical study of Warthin-Finkeldey cells in measles.

An autopsy case of an 18 month old male infant with measles infection is reported. An autopsy revealed generalized lymphadenopathy, splenomegaly and hyperplastic thymus. Histologically, there were many Warthin-Finkeldey cells (WFC) in hyperplastic lymphoid tissues. Although viral particles and inclusions were not detected electronmicroscopically, the infection of measles virus was detected in WFC by immunofluorescent technique using anti-measles antibody. Warthin-Finkeldey cells were morphologically and immunohistochemically divided into two groups. The first type was WFC appearing in the germinal centers of lymphoid tissue, revealing many large nuclei and B cell markers. The second type was WFC appearing in the interfollicular areas and thymus, showing many small hyperchromatic nuclei and T cell markers. The data indicate that there might be a morphologic and immunophenotypic heterogeneity in WFC.

Autopsy↗

PubMed1994

Intra-abdominal venous pressure during laparoscopic cholecystectomy.

Superior vena cava (SVC) and inferior vena cava (IVC) pressures were measured serially during laparoscopic cholecystectomy in which the intra-abdominal pressure was maintained at 12 mmHg. The influences of alteration of position from 15 degrees head-down to 15 degrees head-up and of the operative procedure of holding the gallbladder up to the right subphrenic space on SVC and IVC pressures were mild. IVC pressure was maintained almost equal to the intra-abdominal pressure during prolonged continuous pneumoperitoneum lasting longer than 60 min, while SVC pressure did not change significantly during operation. The discrepancy between SVC and IVC pressures underwent no change during continuous pneumoperitoneum.

Abdomen↗

PubMed1994

Recurrence of primary intracranial germinomas after complete response with radiotherapy: recurrence patterns and therapy.

Nine germinoma patients are described who developed a recurrence after a complete response to radiation without adjuvant chemotherapy. Extraembryonic tumors producing alpha-fetoprotein and human chorionic gonadotropin were excluded from this study. Four patterns of recurrence are described with respect to mechanism and appropriate treatment. Type I germinoma recurrence, characterized by intracranial recurrence caused by an inadequate initial irradiation field was treated by total craniospinal irradiation. Type II recurrence, characterized by a benign teratoma caused by late growth of the teratoma component was treated by surgery alone. All patients with these patterns of recurrence are still alive. Type III local recurrence is characterized by human chorionic gonadotropin- or alpha-fetoprotein-producing tumors of extraembryonic origin. This pattern of recurrence should be treated by chemotherapy or radiosurgery, because all these patients died. Type IV germinoma recurrence consists of extraneural metastasis without evidence of intracranial recurrence. Two of these patients were treated with chemotherapy. In summary, four patients died after recurrence, whereas the remaining five patients survived. The classification of germinoma recurrence patterns should facilitate the selection of the most appropriate treatment. However, it has been difficult to identify the precise histopathology by biopsy or partial resection alone. Furthermore, chemotherapy is indicated in treating germinomas that have a ventriculoperitoneal shunt because of the risk of extraneural metastases.

Adolescent↗

PubMed1994

Assessment of quantitative exercise thallium-201 emission computed tomography in patients with vasospastic angina--value of washout rate analysis.

This study was performed to assess the value of washout rate analysis of quantitative exercise thallium-201 emission computed tomography in vasospastic angina patients without significant coronary stenosis. Quantitative analysis of both thallium-201 perfusion and washout rate before and after drug treatment was performed in 48 patients with vasospastic angina and no significant coronary artery stenosis. All of the patients attained more than 90% of their age-predicted heart rate during each exercise test. Before drug treatment, 26 patients exhibited exercise-induced ischemia (perfusion defects on stress polar map), 17 did not exhibit exercise-induced ischemia (normal stress and washout rate polar maps), and the remaining 5 patients showed no perfusion defects, but did show extensive abnormal washout rates. On coronary angiography, multivessel coronary spasm was documented in 12 of the 26 patients with exercise-induced ischemia, in 7 of the 17 patients without exercise-induced ischemia and in 4 patients with an extensive abnormal washout rate and a normal stress polar map. In the 17 patients without exercise-induced ischemia, the mean washout rate was significantly decreased (p < 0.05) in association with a significant decrease in the double product (p < 0.05) after drug treatment. Of the 26 patients with exercise-induced ischemia, 18 (group 1) showed an increase in the mean washout rate with improved perfusion defect after drug treatment. The remaining 8 patients (group 2) showed a decrease in the mean washout rate with improved perfusion defect after drug treatment, which increased significantly on repeat exercise test performed after additional increased doses of antianginal drugs were administered (p < 0.01). The number of patients with multivessel coronary spasm was significantly high in group 2 (p < 0.01). Thirteen patients showed an extensive abnormal washout rate before drug treatment, including 8 patients with exercise-induced ischemia and 5 patients with no perfusion defects, who showed an increased mean washout rate after drug treatment (p < 0.05). These findings indicate that washout rate analysis aids in the diagnosis in vasospastic angina patients with exercise-induced ischemia. Some patients with exercise-induced ischemia can not be detected by thallium-201 perfusion analysis alone, especially those with multivessel coronary spasm and when this procedure is performed after drug treatment. In addition, a high frequency of abnormal washout rate in vasospastic angina may result not only from exercise-induced ischemia due to main epicardial coronary artery spasm, but also from microspasm, or impairment of microcirculation or myocyte.

Aged↗

PubMed1994

Small gliomas: metabolism and blood flow.

Eight patients with small gliomas (6 low-grade and 2 high-grade) localized in a single gyrus or less than 2 cm diameter were investigated using positron emission tomography and single photon emission computed tomography. All three tumors examined demonstrated hypermetabolism of amino acids. High-grade gliomas demonstrated hypermetabolism of glucose and high blood flow, but normal or low oxygen metabolism. High-grade gliomas also showed accumulation of 201Tl chloride and high or low accumulation of 123I-isopropyl iodoamphetamine. These indications allow preoperative diagnosis of the malignancy of small gliomas, which is important because small gliomas with high-grade malignancy need more extensive removal and adjuvant therapy.

Adult↗

PubMed1994

Changes of the bromodeoxyuridine labeling index of astrocytic tumors between primary and recurrent lesions.

Changes of bromodeoxyuridine labeling index at recurrence were examined in 6 glioblastomas, 2 anaplastic astrocytomas, and 3 fibrillary astrocytomas. Decreased labeling index occurred in 5 glioblastomas, probably due to the effects of combined radiotherapy and chemotherapy, but was not correlated with a favorable outcome. No change of labeling index occurred in 1 anaplastic astrocytoma. Increased labeling index was seen in 1 glioblastoma, 1 anaplastic astrocytoma, and 3 fibrillary astrocytomas, possibly indicating rapid progression just before surgery for recurrent tumor. Recurrent astrocytomas had become anaplastic astrocytoma or glioblastoma, but demonstrated no specific histopathology or labeling index of the primary lesion.

Adult↗

PubMed1994

[A study of the drug distribution on intra-hepatic arterial infusion chemotherapy; how much difference between continuous infusion and rapid infusion?].

The subjects were 41 cases with implantable reservoir systems for unresectable hepatic tumors. We evaluated the difference in drug distribution between intra-hepatic arterial continuous infusion and rapid infusion using hepatic perfusion scintigraphy by 99mTc-macroaggregated albumin via reservoirs. The 41 cases were divided into 2 groups (A and B) according to the imaging of the perfusion scintigraphy. There were 17 cases in group A with equal distribution and 24 cases in group B with a different distribution between the continuous infusion and the rapid infusion. The 24 cases in group B were subdivided into groups according to the distribution of 99mTc-MAA in and around liver. In some cases the distribution pattern after rapid infusion improved more than with continuous infusion. These results suggested that the infusion method must be selected for every case.

Antineoplastic Agents↗

PubMed1994

[A juvenile case of radiation-induced meningioma two years after radiation for craniopharyngioma].

The patient was a 7-year-old boy who received radiation therapy of 50 Gy after total gross removal of a craniopharyngioma. After two years a follow up CT scan showed a new enhanced lesion in the right temporal tip within the previous irradiation field. Total removal of the tumor was performed and its histological examination showed it to be an atypical meningioma. This atypical meningioma satisfied Cahan's criteria. So we diagnosed this atypical meningioma as radiation-induced meningioma. Immunohistochemically this meningioma stained for Vimentin. An electron-microscopical examination showed neither desmosome nor interdigitation. The score of Ki-67 and BrdU-L. I. was very small. Compared with previously reported juvenile radiation-induced meningioma, the latency was very short. The patient received growth hormone (GH) replacement therapy. We suspected relation between GH replacement therapy and short latency. He was discharged without any new neurological deficits and we haven't detected tumor recurrence for two years.

Child↗

PubMed1993

Stimulation of SV40 DNA replication and transcription by Alu family sequence.

The sequence motif GGAGGC (Alu core) is present in the Alu family repeats, where it is required for RNA polymerase III promoter function. This motif is also found in the SV40 origin (ori) of replication. Here, an oligonucleotide containing the Alu sequence was inserted into pSV2CAT, a plasmid composed of the SV40 enhancer/promoter/ori linked to the bacterial chloramphenicol acetyltransferase gene (CAT), to see the effect of the Alu sequence on SV40 DNA replication and transcription. Results of transfection experiments in human HeLa cells showed that the Alu sequence stimulated sequence-specifically replication and transcription in the SV40 system. Stimulation effects on DNA replication were observed when the Alu sequence was placed upstream of enhancer/promoter/ori in either orientation, while effects on transcription were detected only when it was inserted in the normal orientation. These effects correlate with sequence-specific binding of two proteins (40 kDa and 120 kDa) to this motif. In fact, binding was abolished by a mutation in the cognate sequence that disrupted stimulation of replication and transcription. Both proteins bind duplex DNA, while the 40 kDa one also binds the minus strand with high affinity.

Base Sequence↗

PubMed1993

Delayed brain hemorrhage associated with prophylactic whole brain irradiation for pediatric malignant brain tumor: a case report.

Intraparenchymal hemorrhage in the left frontal lobe suddenly occurred in a 7-year-old girl who had undergone partial removal of an undifferentiated brain stem glioma and received craniospinal (30 Gy) and posterior fossa booster (20 Gy) irradiation at the age of 20 months. The brain hemorrhage was thought to be delayed irradiation effect. Follow-up neuro-imaging at age 9 years showed two more small occult chronic and subacute hemorrhages in the brain. The possibility of repeated hemorrhage as a delayed reaction to brain irradiation is emphasized.

Brain Neoplasms↗

PubMed1993

Integration is essential for efficient gene expression of human immunodeficiency virus type 1.

A mutant of human immunodeficiency virus type 1 which carries a frameshift insertion in the integrase/endonuclease region of pol gene was constructed in vitro. Upon transfection into cells, although this mutant exhibited a normal phenotype with respect to expression of gag, pol, and env genes and to generation of progeny virions, no replication-competent virus in CD4-positive cells emerged. An assay for the single-step replication of a defective viral genome dependent on trans complementation by rev protein was established and used to monitor the early phase of viral infection process. Viral clones with a mutation in the vif, vpr, or vpu gene displayed no abnormality in the early phase. In contrast, the integrase mutant did not direct a marker gene expression after infection. Together with an observation that the mutant lacked the ability to integrate, these results indicated that the integration was required for efficient viral gene expression and productive infection of human immunodeficiency virus type 1.

Cell Line↗

PubMed1993

Long-term clinical effects of radiation therapy for primitive gliomas and medulloblastomas: a role for radiosurgery.

The effect of conventional irradiation on primitive gliomas and medulloblastomas was examined for 21 patients and a role for radiosurgery was evaluated. Five patients survived more than 8 years after treatment. However, side effects were recognized not only on neuronal and hormonal functions but also on neurovascular structures in the developing brain. The remaining patients died due to tumor recurrence, dissemination and/or metastases. Although these tumors were radioresponsive, conventional irradiation was inadequate in more than half the cases. A role for Gamma Knife radiosurgery should be considered, especially for young children and recurrences. Radiosurgery could also conceivably contribute to the prevention of tumor dissemination. In all events a multidisciplinary treatment should be considered.

Adolescent↗

PubMed1993

Implications of delayed image on simultaneous thallium-201/technetium-99m pyrophosphate dual emission computed tomography early after acute myocardial infarction.

This study aimed investigate whether thallium-201 and technetium-99m pyrophosphate dual rest-redistribution emission computed tomography early after intracoronary thrombolysis may provide supplementary information for the management of patients with acute myocardial infarction. Fifty patients who received intracoronary thrombolysis underwent simultaneous dual emission computed tomography 3 days after first acute myocardial infarction. All patients who had a technetium-99m pyrophosphate accumulation were selected. Thallium-201/technetium-99m pyrophosphate overlap in the initial and delayed images early after intracoronary thrombolysis identified successful recanalization with sensitivities of 68% and 90% (p < 0.05), specificities of 47% 79% (p < 0.05), positive predictive accuracies of 68% and 88%, negative predictive accuracies of 47% and 80% (p < 0.05), and overall accuracy of 60% and 86% (p < 0.01), respectively. The patients were divided into 3 groups according to the change in thallium-201 uptake from the initial image to the delayed image on dual emission computed tomography: 20 patients had no change in thallium-201 uptake (fixed type), 16 had increases in thallium-201 uptake (redistribution type), and 14 had decreases in thallium-201 uptake (reverse redistribution type). The number of patients with successful recanalization was significantly higher in the redistribution type than in the other types (redistribution type vs reverse redistribution type or fixed type; p < 0.01, respectively). In the redistribution type a frequency of reinfarction in the same infarcted area during the hospital course was significantly higher than in the other types (redistribution type vs reverse redistribution type or fixed type; p < 0.05, respectively), which was mainly due to the patients having high grade residual stenosis. Thus, a thallium-201/technetium-99m pyrophosphate overlap in the delayed image early after acute myocardial infarction can be used as an index for predicting successful early recanalization and probably viable myocardium. In addition, the redistribution patterns on thallium-201 emission computed tomography early after intracoronary thrombolysis can be helpful in identifying patients with successful early recanalization and a high risk subset.

Adult↗

PubMed1993

Ischemic heart disease showing unusual angiographic findings.

Atherosclerotic lesions usually occur in the proximal and middle portion of the coronary arteries. Multiple obstructive lesions appearing only in the peripheral branches without lesions in the proximal or distal portion have not been reported. We encountered a patient with ischemic heart disease showing multiple obstruction in the peripheral branches of the right and left coronary arteries without significant stenotic lesions in the proximal or middle portion. This 49-year-old male was admitted to Yamada Red Cross Hospital due to angina pectoris. Coronary risk factors for him included hypertension, abnormal glucose tolerance, smoking habit, and obesity. Laboratory studies showed a complete blood count and normal blood chemistries, as well as thromboplastin and prothrombin times. Coronary angiography showed multiple obstruction or marked stenosis in the distal portion and peripheral branches; there was no stenosis in the proximal and middle portions. Left ventriculography showed severe hypokinesis in the diaphragmatic segment. Biopsy of the left ventricular endocardium showed interstitial fibrosis but showed no abnormalities in the myocardial fibers or cell infiltration to perivascular areas and vascular walls. Coronary angiography after two months showed multiple lesions, as previously observed. Although ischemic heart disease is caused by various types of vasculitis, embolism, coronary spasm, and fibromuscular dysplasia, in this patient, there were no findings suggestive of causes other than atherosclerosis. This case is interesting in terms of rare angiographic findings and its cause.

Coronary Angiography↗

PubMed1993

A case of dilated cardiomyopathy manifested by exercise-induced left bundle branch block.

We report an extremely rare case of dilated cardiomyopathy manifested by exercise-induced left bundle branch block. A 63-year-old female came to our hospital because supraventricular arrhythmia had been detected at a check-up. A treadmill exercise test induced left bundle branch block. However, chest X-ray and echocardiography revealed no abnormal finding. Two years later, the patient experienced exertional dyspnea. A chest X-ray examination showed cardiomegaly, and echocardiography showed a moderate impairment of left ventricular function with left ventricular dilatation. The diagnosis of dilated cardiomyopathy was made by left ventricular myocardial biopsy. No previous cases have initially shown exercise-induced left bundle branch block which was followed by left ventricular dysfunction due to dilated cardiomyopathy. Careful long-term observation of the clinical course is necessary in patients with exercise-induced left bundle branch block which shows no significant underlying disease.

Bundle-Branch Block↗