Biomedical subjects

J Tanaka

Publications and source records attributed to J Tanaka.

At least 595 records · Page 33Linked to original sources

PubMed1990

[Significance of negative U-waves during anginal attacks: correlation with severity, location and prognosis of coronary stenosis].

Negative U-waves (NU) are not infrequently observed during anginal attacks. Correlations of prevalence of NU and coronary arteriographic findings were observed in 84 patients whose 12-lead electrocardiograms were obtained during anginal attacks. The left anterior descending coronary artery (LAD) was involved in 27 patients, the left circumflex artery (LCX) in 23 and the right coronary artery (RCA) in 34. NU were observed in 44 (52%) of 84 patients with angina; 17 (63%) with LAD, 13 (57%) with LCX, and 14 (41%) with RCA stenosis. The majority (91%) of patients with angina-induced NU had severe (greater than or equal to 90%) coronary stenosis. In the patient group with LAD stenosis, NU were most frequently observed in V4 (59%) greater than V5 (56%) greater than V6 (37%) greater than V3 (33%), while more frequent in V6 (52%) greater than V5 (48%) in the group with LCX stenosis, and in III (29%) greater than a VF (24%) greater than V6 (21%) in the group with RCA stenosis. Thus, the location of the stenosed vessel could be predicted electrocardiographically from the sites of the NU. Coronary revascularization was performed in 10 patients (59%) with LAD stenosis, in nine (69%) with LCX stenosis and in eight (57%) with RCA stenosis. Both anginal attacks and NU resolved after successful coronary revascularization. We concluded that NU proves a highly predictive parameter for detecting and locating significant coronary artery stenosis.

Adult↗

PubMed1990

[Biochemical and molecular biological studies on beta-glucuronidase in myelogenous leukemic cells].

beta-Glucuronidase purified from normal human tissues (placenta, liver and spleen) and granulocytes was composed of 80 kilo-Dalton (kDa), 64 kDa and 18 kDa subunits. The enzyme from human myelogenous leukemic cells contained a 80 kDa subunit as a major component. Amino acid sequencing revealed that N-terminal regions of the 80 kDa from CML cells and the 18 kDa from placenta were identical, and the sequence of the 64 kDa from placenta was identical to the downstream sequence of Gly138 in the 80 kDa enzyme. Therefore, it is probable that the 80 kDa is a precursor form and the 64 kDa is a mature form that is derived by removal of N-terminal 18 kDa peptide (137 amino acids) from the precursor form. These observation simply that proteolytic processing of this enzyme is impaired in myelogenous leukemic cells. The possibility of impaired protease activity against the 80 kDa subunit in CML cells was excluded, since the 80 kDa was not susceptible to several protease sources from normal tissues (placenta and liver) and granulocytes under a variety of reaction conditions. In addition no mutation of the primary structure in myelogenous leukemic cells was detected through analysis of DNA encoding for a peptide, including Gly138 of the enzyme. Therefore, it is suggested that abnormal processing of beta-GUase in the myelogenous leukemic cells is due to alteration in transcriptional or translational step.

Amino Acid Sequence↗

PubMed1990

[Surgical treatment of constrictive pericarditis].

Since 1957, 30 patients with constrictive pericarditis have been treated surgically in Kyushu University Hospital. The surgical approaches were the left anterolateral thoracotomy in 17 patients (group I); the median sternotomy without cardiopulmonary bypass (CPB) in 6 patients (group II); and the median sternotomy with CPB in 7 patients (group III). The hospital mortality was 3.3 percent. The mean postoperative follow-up period was 11.7 years (longest 30 years). The actuarial survival rate at 5 years postoperatively was 88% in total cases (100% in group I, 82% in group II and 52% in group III), 88% at 10 years, 75% at 15 years and 67% at 20 years. Several patients in group III, who underwent complete pericardiectomy using CPB showed severe congestive heart failure and arrhythmia postoperatively. The comparative study between an poor result group (patients who died within 10 years post-operatively) and a good result group (patients who survived more than 10 years postoperatively revealed that preoperative hepatomegaly, atrial fibrillation and the interval between the onset of symptoms and the pericardiectomy influenced the survival rate significantly. These results suggested that pericardiectomy using CPB was a safe method for removing the calcified pericardium in the patient with severe constrictive pericarditis. However, a careful long term follow-up was necessary for the patient with severe myocardial damage even though the complete pericardiectomy was performed.

Adolescent↗

PubMed1990

[Right pulmonary artery obstruction and pulmonary hypertension secondary to aortitis syndrome].

A 56-year-old woman with aortic arch syndrome and finally right pulmonary artery obstruction secondary to Takayasu's aortitis was presented. She had had a history of visual disturbance and dizziness when she looked upward since 1983. On admission in July, 1984, aortography showed obstruction of the right innominate artery and of the left subclavian artery. Pulmonary arterial pressure, pulmonary perfusion and ventilation images seemed to be normal at that time. After discharge from our hospital, she began in 1987, to be aware of dyspnea on effort. Because of this symptom, she was admitted again in March, 1988. The pulmonary perfusion images showed complete lack of perfusion in the right lung, and arterial blood gas showed hypoxia with 62 mmHg in PaO2, 39 mmHg in PaCO2. Cardiac catheterization confirmed pulmonary hypertension with pulmonary artery pressure of 56/18 mmHg. In conclusion, pulmonary perfusion and ventilation scintigraphy proved to be the best way to clarify the nature of a lesion of the pulmonary artery in aortitis syndrome.

Adult↗

PubMed1990

[A case of silent posterior myocardial ischemia/left circumflex artery obstruction detected by prominent U-wave in right precordial leads].

A 64-year-old woman with a history of hypertension for ten years and of syncope 18 month previously visited our Division of Cardiology on 12 June, 1989. The S4 and mitral regurgitation were audible at the apex, and her electrocardiogram showed ST-depression in leads II, aVF, V5-6 and prominent U-wave (PU) in V1-3 when first seen. Then, she was thought to have a posterior myocardial ischemia. PU in V1-3 diminished whereas T-wave increased after nitrate and Ca++ blocker. Ergometer exercise ECG showed ST-depression in II, III, aVF, V4-6 and PU with decreased T-wave in V2-3 with no apparent symptoms. Simultaneously, Tl-201 myocardial imaging demonstrated a transient posterior defect. A silent posterior myocardial ischemia was, therefore, confirmed. Coronary arteriograms demonstrated subtotal obstruction of the proximal left circumflex artery, and the peripheral site was filled by collaterals from the right coronary artery. Angina-induced PU in the right precordial leads proved to be useful in detection of posterior myocardial ischemia, and this marker may also improve the possibility of detection of silent posterior ischemia.

Coronary Disease↗

PubMed1990

A new method of retrograde cardioplegic administration. Right ventricular protection by right atrial perfusion cooling.

Retrograde administration of cardioplegic solution via the right atrium with continuous cooling of the right ventricular cavity (right atrial perfusion cooling) was assessed for its protective effect in 12 dogs with occlusion of the right coronary artery subjected to global ischemia for 60 minutes. After an initial administration of 4 degrees C crystalloid cardioplegic solution by antegrade aortic perfusion, myocardial protection was established either by right atrial perfusion cooling (group I; n = 6) or by antegrade aortic perfusion alone (group II; n = 6). The right ventricular temperature was approximately 15 degrees C in group I and 20 degrees C in group II. After ischemia for 60 minutes, the adenosine triphosphate content of the right ventricular free wall was significantly higher in group I than in group II (24.4 +/- 1.45 versus 13.8 +/- 2.34 mumol/gm dry weight, p less than 0.05). The percent recovery of right ventricular contractility, which was evaluated by end-systolic pressure-volume relationships, was significantly better in group I at each reperfusion period (30 minutes: 130.0% +/- 9.6% versus 86.1% +/- 11.8%, p less than 0.05; 60 minutes: 159.6% +/- 12.9% versus 96.5% +/- 20.1%, p less than 0.05). Postischemic right ventricular stiffness (reciprocal value of compliance) increased in group II compared with group I, although the difference was not statistically significant. There were no major differences in percent recovery of the left ventricular end-systolic pressure-volume relationships between the two groups. The evidence suggests that the right atrial perfusion cooling method produces excellent right ventricular protection.

Animals↗

PubMed1989

[Clinical investigation of the branching formation of the bronchial arteries in the Japanese].

It is imperative to be familiar with anatomical variation in the branching formation of the bronchial artery for radiologists attempting an interventional angiography to the pulmonary diseases such as hemoptysis or pulmonary carcinoma. The anatomy of the bronchial arteries reported by Cauldwell et al. is the most frequently quoted literature in the world as well as in Japan. However, we had noticed that some discrepancies exist between our clinical experience and those in Cauldwell's report regarding anatomical variation of the bronchial arteries. Then, we reviewed the bronchial arteriograms in 640 patients. We included 412 patients in investigation, in which it was possible to identify the branches supplying all pulmonary lobes. In 50 out of 640 patients, catheterization of the branches supplying the lesion was failed. Branching formation of the bronchial arteries is extremely variable and complicated by presence of the accessory bronchial arteries and anastomosing branches from the systemic arteries, which may be enlarged in various pathological conditions. Our results showed that the most common branching type was single artery on each side (50.0%), followed by common trunk (14.1%). The incidence of single on the right and dual on the left, most common in Cauldwell's series, was only 12.9%. Kasai and Chiba also pointed out these differences in their detail report investigating 100 cadavers. These discrepancies between the data may be due to differences of methodology or due to differences between the races. The authors feel that Cauldwell's data should not be referred to the anatomical variation of the bronchial artery in Japanese.

Asian People↗

PubMed1989

Inputs from the nucleus of the solitary tract to subfornical organ neurons projecting to the paraventricular nucleus in the rat.

Extracellular single-unit activity was recorded from 26 subfornical organ (SFO) neurons antidromically identified as projecting to the hypothalamic paraventricular nucleus (PVN) in urethane-anesthetized male rats. Of these identified SFO neurons, 10 displayed an inhibitory response and 2 exhibited an excitatory response in neuronal excitability following electrical stimulation of the nucleus of the solitary tract (NTS), while the remaining neurons were unresponsive. Eight out of 10 SFO neurons that demonstrated the inhibitory response to NTS stimulation also displayed a reduction in ongoing activity in response to activation of peripheral baroreceptors, achieved by rising arterial blood pressure with an intravenous administration of the alpha-agonist metaraminol, whereas the remaining responsive neurons to NTS stimulation were ineffective. These results show that a part of SFO neurons projecting to the PVN may receive inhibitory inputs from the peripheral baroreceptors through NTS neurons.

Action Potentials↗

PubMed1989

Impaired responsiveness of paraventricular neurosecretory neurons to osmotic stimulation in rats after local anesthesia of the subfornical organ.

Extracellular recordings were obtained from 32 phasically active neurosecretory cells in the hypothalamic paraventricular nucleus (PVN) of urethane-anesthetized male rats. None of the PVN cells changed their activity to intracarotid infusions of isotonic saline (0.15 M NaCl solution, 0.05 ml). Of these PVN neurons, 26 displayed an increase in neuronal activity following intracarotid infusions of hypertonic saline (0.2 M NaCl solution, 0.05 ml), while the remainder were unresponsive. Microinjection of the local anesthetic lidocaine into the subfornical organ (SFO) reversibly diminished the excitatory response to the infusions of hypertonic saline in 10 out of 15 PVN neurons tested, whereas the injection of lidocaine into the vicinity of the SFO (n = 4) or the third ventricle (n = 4) did not cause a marked change. These results show an involvement of the SFO in the mechanism of osmotic activation of putative vasopressin (AVP)-secreting neurons in the PVN.

Action Potentials↗

PubMed1989

Prognostic value of electrically elicited blink reflex in neonates.

The electrically elicited blink reflex (BR) was evaluated in 80 normal neonates and 12 neonates with neurologic abnormalities. In normal subjects, R1 and bilateral R2 responses were elicited both while awake and in a quiet sleep state. Whereas the R1 response was consistently elicited in the active sleep state, as well as while awake, the ipsilateral R2 response was markedly suppressed and the contralateral R2 response was almost absent. The BR in neonates with neurologic abnormalities showed the following variable results: normal, prolonged latency, or suppressed response at initial recording. Abnormal BRs were detected in most neonates with respiratory or sucking problems. While neonates in whom a suppressed response or prolonged latency persisted for over three months had a poor prognosis, those with normal BRs or early correction of the BR abnormality had almost normal development. The BR appears to be useful not only to evaluate brain-stem function in the neonatal period but also to predict subsequent outcome.

Blinking↗

PubMed1989

Involvement of the median preoptic nucleus in the regulation of paraventricular vasopressin neurons by the subfornical organ in the rat.

Extracellular recordings in urethane-anesthetized male rats indicated that electrical stimulation of the subfornical organ (SFO) alters the activity of 54 out of 62 phasically firing neurosecretory neurons in the hypothalamic paraventricular nucleus (PVN); 44 cells demonstrate an increase in excitability; 10 cells display a depression in their activity. In 14 out of 38 PVN cells tested, SFO stimulation-evoked excitations were abolished by pretreatment with the angiotensin II (ANG II) antagonist, saralasin (Sar), in the region of the median preoptic nucleus (MnPO). Inhibitory responses (n = 7) were not affected. Microinjection of ANG II into the region of the SFO produced either a facilitation (n = 28) or no effect (n = 6) on the excitability of phasically active PVN neurosecretory cells and the facilitatory effect of 9 out of 23 cells tested was prevented by pretreatment with Sar in the region of the MnPO. All the PVN cells which had excitatory responses to either electrical (n = 7) or chemical (n = 9) stimulation of the SFO that were blocked following the pretreatment could also be activated by intravenous administration of ANG II. Furthermore, this activation was blocked (n = 10) or attenuated (n = 6) by pretreatment with Sar in the region of the MnPO. These results show an involvement of both the MnPO and the SFO for the regulation of excitability of putative vasopressin (VP)-secreting PVN neurons, and suggest that MnPO neurons sensitive to ANG II may relay activation of SFO neurons by circulating ANG II to putative VP-secreting PVN neurons which result in enhanced excitability.

Action Potentials↗

PubMed1989

Clinicopathological features of malignancy in hepatocellular carcinoma.

The clinicopathological features showing the malignancy of hepatocellular carcinoma were investigated by retrospectively analyzing the postoperative prognosis after hepatic resection. The long-term prognosis was strongly affected by the existence of portal tumor invasion or intrahepatic metastasis as indicated by the following results. The 3-year cumulative survival rates were 61% and 38% for patients in portal vein tumor invasion groups (Vp0 and Vp1 (P less than 0.05). No patients with Vp2 or Vp3 could survive beyond 3 years after hepatic resection. Similarly, patients with intrahepatic metastasis IM0 showed a better prognosis, compared to those with IM2 or IM3 (P less than 0.05). In addition, the grade of tumor cell anaplasia to some extent affected the prognosis, but not the tumor growth pattern at the tumor/non-tumor boundary. The tumor growth rate, estimated by the alpha-fetoprotein doubling time, was not connected with venous invasion or intrahepatic metastasis, but it became shorter at the time of a recurrence. It is concluded that, from the standpoint of a long-term prognosis, the pathological features showing malignancy appear in venous invasion and intrahepatic metastasis.

Carcinoma, Hepatocellular↗

PubMed1989

Mitochondria covered with a net of parallel and latticed filaments in nigral neurons of monkeys with experimental parkinsonism.

Nigral neurons of crab-eating monkeys treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) showed a peculiar configuration occasionally in mitochondria. The outer membrane of mitochondria was covered with a net of fine parallel or latticed filaments, which turned spirally about the long axis of the mitochondria. The filaments were approximately 8 nm in diameter: parallel filaments were arranged at intervals of about 13 nm from center to center; and latticed filaments intersected each other at an angle of almost 135 degrees. When mitochondria were present in groups, the intermitochondrial gap was occasionally filled with the same parallel filaments. The netted mitochondria were frequently associated with intramitochondrial abnormalities such as small floculent inclusions and disintegrated cristae. Only one or two netted mitochondria were counted in the perikaryon of one section of an injured neuron. They appeared in about one-third of mildly or moderately injured neurons in three of six MPTP-treated monkeys, and not in normal surviving and recovering neurons of treated animals, or in neurons of control animals. We consider the netted mitochondria to be a pathological configuration related to a metabolite of oxidation of MPTP, and to be different from the stubby mitochondria reported in amyotrophic lateral sclerosis (ALS) and a non-ALS case.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

PubMed1989

Prognosis and prognostic factors in chronic pancreatitis.

To evaluate the prognosis and prognostic factors of chronic pancreatitis, 84 patients with alcoholic chronic pancreatitis and 51 with nonalcoholic chronic pancreatitis have been followed for 1-21 years (average of 7.1 years). The follow-up period was defined as the period from diagnosis to death in those who died and to the present in those still alive. The following conclusions were obtained. (1) Patients with alcoholic chronic pancreatitis showed a significantly higher mortality rate (26.2%) and cancer death rate (8.3%) than the age- and sex-matched population. In patients with nonalcoholic chronic pancreatitis, however, the difference did not reach the level of statistical significance, although both rates tended to be higher. (2) Patients with alcoholic chronic pancreatitis showed a significantly poorer prognosis than those with nonalcoholic chronic pancreatitis. (3) Frequent causes of death in chronic pancreatitis were cancer (11 cases) and diabetes-associated conditions (renal failure in three cases, intractable pneumonia in one, hypoglycemic shock in two, and myocardial infarction in two). Death directly from pancreatitis was observed in four. (4) Unfavorable prognostic factors in alcoholic chronic pancreatitis included heavy drinking, continuance of drinking after diagnosis, smoking, insulin-dependent diabetes, and an advanced age. In nonalcoholic chronic pancreatitis, however, patients' age was the only significant prognostic factor; smoking did not reach the level of statistical significance, although it tended to lead to a poorer prognosis.

Adult↗

PubMed1989

Targeting chemotherapy for intrahepatic periductal lymphatic invasion by mitomycin C adsorbed to activated charcoal in hepatic hilar bile duct cancer.

A new dosage form of anticancer agent, mitomycin C adsorbed to activated charcoal (MMC-AC), was evaluated in the rabbit model of hepatic hilar bile duct cancer. The model was produced by inoculation of VX2 cells into the wall of the hepatic hilar bile duct. Histologic examination revealed that the mode of spreading of VX2 cells in the model closely resembles that of human bile duct cancer. On the other hand, selective accumulation of MMC-AC into the lymphatic vessels around the intrahepatic bile duct was observed after its injection into the hepatic hilum in rabbits. To assess the anticancer effect, 1 ml of MMC-AC was injected into the bile duct wall near the VX2 tumor. The numbers of lymphatic vessels where necrosis of VX2 cells was observed in one-third or more were 34 of 103 vessels 0.5 cm away from the tumor, 23 of 80 vessels 1.5 cm away, and 9 of 67 vessels 2.5 cm away. We believe that the injection of MMC-AC into the hepatic hilum can be effective adjuvant therapy for hepatic hilar bile duct cancer.

Animals↗

PubMed1989

Toxicity to medaka of solutions of fenitrothion degraded by strong alkali.

Various experiments were conducted to examine the effects of degradation products on organisms. Fenitrothion (MEP) emulsions adjusted to pH 10 or 14 were degraded by exposure to natural sunlight in winter with heat. Medaka eggs were exposed to various concentrations of the degraded solutions and an untreated MEP emulsion for 5 days starting 4-5 h following fertilisation. The eggs were then allowed to develop in dechlorinated tap water until the fish reached 3 months of age. The hatching rate and rate of survival in the degraded solutions tended to be lower than those in the untreated MEP emulsion, and the incidence of abnormal fry in the degraded solutions was higher than that of the untreated MEP emulsion. It thus appears that degradation products formed by MEP have toxic effects on medaka.

Journal Article↗

PubMed1989

Evaluation of gamma-enolase as a tumor marker for renal cell carcinoma.

To evaluate whether serum gamma-enolase is a useful marker for renal cell carcinoma alpha and gamma-enolases in tissues of 36 renal cell carcinomas and 13 normal kidneys, and in sera of 103 renal cell carcinoma patients were determined with an enzyme immunoassay system. Tissue gamma and alpha-enolase levels were 34 and 2.3 times higher, respectively, in renal cell carcinoma than in normal renal cortex. The tissue gamma enolase-to-total enolase value of renal cell carcinoma (5.3 per cent) was significantly higher than that of normal cortex (0.29 per cent) and medulla (0.51 per cent). Over-all serum gamma-enolase levels were elevated (more than 6.0 ng. per ml.) in 53 of 103 patients (51 per cent) with renal cell carcinoma. In regard to stage the positive rates were 34 per cent (12 of 35) of patients with stage I, 22 per cent (2 of 9) with stage II, 80 per cent (12 of 15) with stage III, 61 per cent (22 of 36) with stage IV and 61 per cent (5 of 8) with recurrent disease. The mean value of serum gamma-enolase in renal cell carcinoma (8.0 +/- 5.7 ng. per ml.) was significantly higher than that of normal subjects (3.1 +/- 0.9 ng. per ml., p less than 0.001). The mean value of serum gamma-enolase in patients with high stage tumors (III and IV, 9.9 +/- 6.8 ng. per nl.) was significantly higher than that of low stage tumors (I and II, 5.8 +/- 3.0 ng. per ml., p less than 0.001). In 39 patients treated by complete surgical excision serum gamma-enolase was significantly reduced postoperatively (p less than 0.01). Furthermore, 7 of 8 patients whose serum gamma-enolase levels were determined serially had levels within the normal range postoperatively that increased when distant metastases appeared. These results indicate that serum gamma-enolase could be a useful tumor marker to stage disease and monitor treatment in patients with renal cell carcinoma.

Adult↗

PubMed1989

Microangiographic study of spinal cord injury and myelopathy.

Post-mortem microangiography has been performed in 12 patients with traumatic cervical cord injury, 2 patients with myelopathy, and one patient with post-traumatic syringomyelia. Microangiography defined 4 zones in the injured spinal cord. In traumatic injury, the size and extent of the non-filling area (Zone 1) was directly related to the injury force. Subsequently these areas became cavitated. Surrounding the non-filling area, widely extending areas demonstrated filling of capillaries but showed damaged neurons and axons (Zone 2). In the chronic stage, Zone 2 replaced by gliomesenchymal tissue. The capillaries in the gliomesenchymal scars revealed a distorted abnormal arrangement (Zone 3). In a case with myelopathy, the hypervascular areas (Zone 4) were observed just around the chronically compressed area. The vascular increases were considered to be a reaction against chronic compression. In a patient with post-traumatic syringomyelia, the vascular network of the posterior grey matter disappeared and the central arteries were distorted by the distending forces of the syrinx. The microangiographs suggested that vascular factors might play a significant role in original cavity formation; but in cavity extension, these factors were not primary.

Adult↗