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N Hatori

Publications and source records attributed to N Hatori.

At least 19 recordsLinked to original sources
PubMed1998

The effect of nitric oxide synthase inhibitor on reperfusion injury of the brain under hypothermic circulatory arrest.

OBJECTIVE: The objective of this study was to investigate the protective effects of nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester hydrochloride, on reperfusion injury of the brain under hypothermic circulatory arrest. METHODS: After cardiopulmonary bypass was established using 12 piglets each weighing about 30 kg, the animals were cooled to a brain temperature of 20 degrees C and circulatory arrest was performed for 90 minutes followed by reperfusion for 120 minutes. The level of nitric oxide within the brain was measured with a needle electrode inserted into the brain. In the treatment group, N(G)-nitro-L-arginine methyl ester hydrochloride was administered with an intravenous injection of 1.5 mg/kg at the onset of the reperfusion followed by a 60-minute continuous venous infusion of 1.5 mg/kg/hr. RESULTS: In the control group, nitric oxide levels within the brain increased not during ischemia but during reperfusion, and the level after 120 minutes of reperfusion increased significantly compared with that of before circulatory arrest. But in the treatment group, N(G)-nitro-L-arginine methyl ester hydrochloride administered at the onset of reperfusion inhibited nitric oxide production during reperfusion. A significant difference was observed between the groups regarding the nitric oxide level after 120 minutes of reperfusion. Regarding cerebral blood flow, excess lactate, and cerebral tissue water content, no significant difference was observed between the groups. However, recovery of somatosensory evoked potential after 120 minutes of reperfusion was detected in all six animals in the treatment group, but none in the control group (p = 0.001). CONCLUSION: These data suggest that N(G)-nitro-L-arginine methyl ester hydrochloride protects the brain against reperfusion injury under hypothermic circulatory arrest.

Animals↗
PubMed1998

Coronary thrombosis/thrombolysis in pigs: effects of heparin, ASA, and the thrombin inhibitor inogatran.

UNLABELLED: The aim of the present study was to develop a coronary thrombolysis model using the copper coil technique in closed-chest pigs. The first goal (protocol I) was to obtain a reproducible size of myocardial infarction by controlling the coronary occlusion period, a prerequisite for evaluation of myocardioprotective interventions. The second goal (protocol II) was to study if thrombin and platelet aggregation inhibitors influence the rate of thrombolysis, the degree of reocclusion, and the time of coronary patency when added to a thrombolytic regimen (recombinant tissue-type plasminogen activator, rt-PA). Coronary thrombosis was produced by insertion of a thrombogenic copper coil into the LAD of 40 anesthetized pigs. The animals were divided into six groups as follows: Protocol I, group 1: Open-chest, lysis initiated with intracoronary rt-PA (50 mg) concomitant with intravenous heparin and acetylsalicylic acid (ASA) (n=6). Group 2: Closed-chest, lysis initiated with intracoronary rt-PA concomitant with intravenous heparin and ASA (n=10). Protocol II, group 3: Closed-chest, lysis initiated with intravenous rt-PA (n=6). Group 4: Closed-chest, lysis initiated with intravenous rt-PA concomitant with heparin (n=6). Group 5: Closed-chest, lysis initiated with intravenous rt-PA concomitant with inogatran, a low molecular weight thrombin inhibitor (n=6). Group 6: Closed-chest, lysis initiated with intravenous rt-PA immediately after intravenous administration of ASA (n=6). Protocol 1; Reperfusion was achieved in all closed- and open-chest pigs. The time to thrombolysis was 5+/-1.6 and 6+/-3.0 min (mean+/-SD) for closed- and open-chest pigs, respectively. Reocclusions were rare (one in group 1). The size of the ischemic myocardial area was 21+/-11% of the left ventricular area in group 1 and 22+/-6% in group 2. The corresponding values for infarct size as a proportion of the ischemic area were 58+/-10% and 68+/-14%, respectively. The closed-chest model was subsequently used to study the effect of the thrombin and platelet aggregation inhibitors (inogatran, heparin, and ASA) as conjunctive agents to rt-PA-induced thrombolysis (groups 3-6). To mimic its clinical use, rt-PA was administered intravenously. Time to lysis after rt-PA only (group 3) was 33+/-24 min. Concomitant treatment with heparin (group 4), inogatran (group 5), and ASA (group 6) did not significantly influence time to lysis. All adjunctive compounds did, however, prolong the time to reocclusion, which occurred in 100%, 75%, 67%, and 20% of the animals in groups 3, 4, 5, and 6. Thus, concomitant treatment with heparin and inogatran did not shorten time to lysis or reduce the reocclusion rate, and ASA turned out to be the only effective adjunct to rt-PA, significantly reducing both time to and frequency of reocclusion (p < 0.05). CONCLUSION: The described closed-chest pig model was feasible as regards the induction and lysis of a thrombus in the left coronary artery, giving reproducible areas of myocardial ischemia and infarction. This model was useful for the evaluation of pharmacological interventions in the thrombolysis process.

Animals↗
PubMed1997

[Surgical treatment for primary cardiac malignant lymphoma].

A 60-year-old woman who complained of palpitation was diagnosed as ventricular tachycardia on electrocardiography and admitted to our hospital. The ultrasonic cardiography showed cardiac tumor in right ventricle and right atrium. Due to the obstruction of the right ventricle inflow by the tumor, we immediately performed resection of cardiac tumor and repair of right ventricle wall under cardiopulmonary bypass. The tumor was diagnosed as malignant lymphoma by pathological examination for surgical specimen of tumor. After operation her general condition was good, but residual cardiac lymphoma developed large size. We performed radiation therapy for cardiac lymphoma. Therefore the lymphoma was reduced to minimum size. Six months after operation metastatic malignant lymphoma appeared at whole body. So we performed chemotherapy for reduction of systemic malignant lymphoma. At first the chemotherapy was very effective. But metastasis spread rapidly and effectiveness of chemotherapy reduced. Thirteen months after operation she died for respiratory distress, probably due to metastatic brain tumor.

Female↗
PubMed1997

[The effect of nitric oxide synthase inhibitor on reperfusion injury to the brain under hypothermic circulatory arrest].

The effect of nitric oxide synthase inhibitor-NG-nitro-L-argine methyl ester (L-NAME)-on reperfusion injury of the brain under deep hypothermic circulatory arrest was experimentally investigated in sixteen piglets weighing about 30 kg. Cardiopulmonary bypass was established and animals were cooled to a brain temperature of 20 degrees C and circulatory arrest was performed for 60 minutes followed by reperfusion of 120 minutes. The value of nitric oxide (NO) within the brain was measured with a needle electrode which was inserted into the brain. In the treatment group L-NAME was administered with a intravenous injection of 1.5 mg/kg at the beginning of the reperfusion followed by a 60-minute continuous venous infusion of 1.5 mg/kg/hour. In the control group the value of NO after 120 minutes reperfusion increased significantly compared with pre-circulatory arrest, but in the treatment group it did not. There was significant difference between the groups regarding the NO value after 120 minutes reperfusion. Blood pressure after 120 minutes reperfusion in the treatment group was a little higher than the control group, but there was no significant difference between the groups regarding cerebral blood flow, excess lactate and cerebral tissue water content. However, recovery of SEP after 120 minutes reperfusion was detected in all 8 cases of the treatment group, but only in one of the control group (p < 0.001). This data suggests that L-NAME protects the brain against the reperfusion injury under deep hypothermic circulatory arrest.

Animals↗
PubMed1997

[A case report of the subclavian pseudoaneurysm due to blunt chest trauma without fracture].

A young adult patient, 21 years old female, with left subclavian pseudoanurysm caused by blunt chest trauma is reported. The patient was carried to the emergency room of our hospital with the blunt trauma and lung contusion due to the traffic accident. On chest roentgenogram no fractures of ribs and subclavia were seen, but the superior mediastinum was widened. Superior mediastinal hematoma was suspected by CT scan. Following examination of aortogram revealed an pseudoaneurysm of the left subclavian artery at the origin of left internal artery. Emergency operation was performed with left postero-lateral thoracotomy and the aneurysm was located just the point at the bifurcation of internal mammary from left subclavian artery. Internal mammary artery was clipped and the fissure of the subclavian of the subclavian artery was repaired by direct suture under temporary occlusion of the subclavian artery. Postoperative course was uneventful and superior mediastinal hematoma was not noticed on chest roentgenogram and CT of 18 days postoperatively.

Adult↗
PubMed1996

[Evaluation of non-uniform attenuation correction using simultaneous transmission and emission computed tomography--basic analysis with myocardial phantom].

Simultaneous transmission emission protocol (STEP), developed for the non-uniform attenuation correction of single photon emission computed tomography (SPECT) was evaluated using the cardiac phantom prepared with and without a myocardial wall defect. Emission computed tomography (ECT) of the cardiac phantom using 201Tl was acquired. Transmission data (TCT) were taken using a line source of 99mTc. Myocardial images with STEP method were superior in the homogeneity of intramyocardial radioactivity and spatial resolution to the conventional SPECT images. This is an excellent method because of the accurate matching position between TCT and ECT images and shortening the examination time by simultaneous data acquisition. It would be clinically useful for diagnosing various myocardial diseases.

Heart↗
PubMed1996

[A basic and clinical evaluation of a new immunoradiometric assay kit for human serum tissue polypeptide antigen (TPA)].

A new immunoradiometric assay kit (IRMA) of human serum tissue polypeptide antigen (TPA) based on combination monoclonal antibodies was evaluated. Using a new TPA-IRMA, the procedure of TPA measurement was faster and the range of measurement was more wide than a conventional TPA-IRMA. 89% (76/85 cases) of patients with malignant tumor and 96.4% (27/28) of patients with metastatic malignant tumor were positively detected. This assay of new TPA-M kit is sensitive to the level of serum TPA which is corresponding to a therapy. It is concluded that a new TPA-IRMA is very useful in monitoring and assessing malignant tumors.

Adult↗
PubMed1996

[Ventricular septal perforation due to weak blunt chest trauma. A case report].

Traumatic ventricular septal perforation (VSP) is a rare type of heart injury. This case report describes a 72-year-old Japanese woman who got VSP secondary to weak blunt chest trauma on a train. A two-dimensional color doppler echocardiography and cardiac catheterization study revealed a VSP at muscular portion near the apex. On the 48th day following injury, she was performed a patch closure through left ventriculotomy under cardiopulmonary bypass. The patient was discharged uneventfully.

Aged↗
PubMed1995

[A construction of a PACS and reporting system linked with the hospital information system in Gunma University Hospital].

A PACS (Picture Archiving and Communication System) and reporting system were introduced into Gunma University Hospital. These systems were linked with Hospital Information System (HIS), enabling us to refer to images, such as those of CR, CT, MRI and scintigraphy, at wards and conference rooms within a reasonable times. Bone scintigraphy and a report on it are illustrated as an example. A standardized protocol for the interface between PACS and the imaging format must be established without delay for the progress of PACS.

Computer Communication Networks↗
PubMed1995

[A pilot study with lung-cancer screening CT (LSCT) at the secondary screening for lung cancer detection].

We have developed computed tomography (CT) equipment for lung-cancer screening (named LSCT) that can be used exclusively for lung-cancer screening with spiral volumetric CT and is available on a screening car. A pilot study with LSCT was performed from November 1992 to January 1993 on 118 screenees at the secondary examination of lung-cancer screening. Scan parameters were as follows: 120 kVp, 50 mA, slice thickness 10 mm, table feed 10 mm/sec, scan time 2 sec/rotation. All the screenees were scanned under quiet respiration instead of the breath-hold technique. Under these scan parameters, LSCT images were almost free from respiratory motion artifacts even at the lung base. Continuity of the bronchial tree and vessels was well maintained in consecutive slices. Pulmonary nodules approximately 5 mm in diameter were clearly depicted. By LSCT, 43 of 118 screenees were diagnosed to need further examinations. And 33 out of 43 screenees underwent detailed examinations. Finally, 16 lung cancers were confirmed. Ten of 16 patients with lung cancer underwent surgery; nine were in stage I and one in stage IIIA. LSCT was considered to be useful in lung-cancer screening.

Adult↗
PubMed1994

Biocompatibility of heparin-coated membrane oxygenator during cardiopulmonary bypass.

The biocompatibility of the cardiopulmonary bypass (CPB) circuit, in which an oxygenator is solely heparinized, was assessed by systemic inflammatory reactions as an indicator during CPB. Fourteen patients, 11 males and 3 females, underwent coronary artery bypass surgery and were randomly divided into 2 groups of 7 patients each. For the heparin-coated oxygenator group (Group H), a heparin-coated membrane oxygenator was used in the CPB circuit, and in the control (Group C) an uncoated membrane oxygenator was employed. Systemic inflammatory reactions, such as platelet activation, prostaglandin production, complement activation, and activated granulocyte released substance, were measured prior to, during, and 6 h after CPB. The number of platelets decreased after protamine administration in both groups (14.5 +/- 4.7 x 10(4)/microliters in Group H and 13.8 +/- 8.7 x 10(4)/microliters in Group C) and returned to baseline levels in Group H while it remained decreased in Group C at 6 h after CPB. The platelet factor 4 level was significantly lower in Group H (181 +/- 40 ng/ml) than in Group C (297 +/- 131 ng/ml) after protamine administration. Thromboxane-B2 (TXB2) rose during CPB in both groups; however, there were significantly different levels of TXB2 between the 2 groups at 60 min after CPB (293 +/- 258 pg/ml in Group H versus 408 +/- 120 pg/ml in Group C) and after protamine administration (259 +/- 122 pg/ml in Group H versus 709 +/- 418 pg/ml in Group C). Plasma concentrations of granulocyte elastase were significantly lower in Group H at 30, 60 and 90 min, immediately after, and post-CPB than those of Group C.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗
PubMed1994

Ischemic and nonischemic tissue concentrations of felodipine after coronary venous retroinfusion during myocardial ischemia and reperfusion: an experimental study in pigs.

Tissue and plasma concentrations of felodipine, a dihydropyridine (DHP) calcium antagonist, retroinfused through the coronary venous system were studied in 27 pigs. The animals underwent 45-min myocardial ischemia followed by 4-h reperfusion. Felodipine (7 nmol/kg body weight) was administered in the coronary vein for 30 min, 5 min before reperfusion. Concentrations of felodipine in the ischemic and nonischemic myocardium and in plasma were determined by gas chromatography. In the ischemic area, felodipine concentration at start of reperfusion was 304 +/- 285, 171 +/- 160, and 52 +/- 47 nmol/kg (mean +/- SD) in the subepicardial, midmyocardial, and subendocardial layer, respectively. Corresponding concentrations in the nonischemic area were 15 +/- 13, 17 +/- 14, and 16 +/- 15 nmol/kg (p < 0.05 vs. ischemic area). Subepicardial concentration was highest at start of reperfusion, whereas concentrations in other layers peaked at the end of retroinfusion. The transmural concentration gradient of felodipine in the ischemic area decreased progressively during the reperfusion period. The nonischemic tissue concentration increased slightly during the reperfusion period. The plasma concentration was very low throughout the study (peak = 3.2 +/- 1.4 nM at 30 min). Coronary venous retroinfusion of felodipine resulted in profound accumulation of the drug, specifically in ischemic myocardium. The plasma concentration was low and did not affect systemic hemodynamics. Coronary venous retroinfusion is considered an advantageous technique for selective drug delivery.

Animals↗
PubMed1993

Acute cobalt exposure and oxygen radical scavengers in the rat myocardium.

Excessive amounts of cobalt are cardiotoxic, although the mechanism for this toxicity remains unclear. We studied the effects of acute cobalt exposure on the activities of free radical scavengers in the myocardium in 5 groups of rats. Six rats served as a control group and were given a daily subcutaneous injection of 1 ml saline for 8 days. The other 4 groups of rats received a daily injection subcutaneously of cobalt chloride in doses of 1 mg/kg bw, 5 mg/kg bw, 20 mg/kg bw and 50 mg/kg bw, respectively for 8 days. There was a marked and dose-dependent accumulation of cobalt in the myocardium of the cobalt exposed rats. Creatine kinase, copper-zinc superoxide dismutase (CuZn-SOD) and alpha-tocopherol content did not differ between the control and the cobalt exposed groups. The activity of glutathione peroxidase increased, while the activity of manganese-superoxide dismutase (Mn-SOD) was significantly reduced in the cobalt exposed groups. There was an inverse relationship (r = 0.60, P < 0.0001) between the cobalt content and Mn-SOD activity in the myocardium. These results suggest that acute cobalt cardiotoxicity may involve a reduction of intrinsic scavengers resulting in an increased vulnerability to oxygen free radical toxicity.

Animals↗
PubMed1993

Coronary venous retroinfusion of felodipine reducing infarct size without affecting regional myocardial blood flow.

Effects on the ischaemic and reperfused myocardium of felodipine, a vasoselective calcium blocker, retrogradely infused into the coronary vein was investigated in a porcine model. Sixteen open-chest pigs underwent 45 min of myocardial ischaemia by occlusion of the left anterior descending coronary artery followed by 4 h of reperfusion. Either felodipine (felo-retro group, 7 nmol.kg-1: n = 6) or the corresponding amount of vehicle (vehicle group: n = 5) was retroinfused over 30 min starting 5 min prior to reperfusion. In a third group, the same amount of felodipine was administered intravenously (felo-i.v. group n = 5). Myocardial regional blood flow was measured with radioactive microspheres prior to ischaemia and at different times of reperfusion. Infarction size, expressed as a percentage of the area at risk, was significantly reduced to 62 +/- 12% in the felo-retro group as compared to 86 +/- 12% (P < 0.05) and 94 +/- 5% (P < 0.05) in the vehicle and felo-i.v. group, respectively. Following an early hyperaemia, the regional blood flow decreased uniformly in the reperfused myocardium in all three groups and there were no significant differences between the groups at any period of reperfusion. In conclusion, felodipine retroinfused into the coronary vein could salvage ischaemic and reperfused myocardium without affecting the regional blood flow. The mechanism of this protective effect should be explained by factors other than an increased myocardial blood flow during reperfusion.

Animals↗
PubMed1993

Coronary venous retroinfusion of felodipine reduces myocardial necrosis after coronary occlusion and reperfusion.

The effect of the vasoselective calcium antagonist felodipine on myocardial necrosis was studied in 14 anesthetized pigs subjected to 45-min occlusion of the left anterior descending coronary artery (LAD) followed by 24-h reperfusion. Felodipine (7 nmol/kg, n = 7), or the corresponding amount of vehicle diluted in 300 ml saline (n = 7) was infused in the great cardiac vein for 30 min beginning 5 min before onset of reperfusion. Regional myocardial function was measured as percentage of systolic segment shortening (%SS) by sonomicrometry. The recovery in ischemic myocardium was significantly already better among felodipine-treated animals after 30-min reperfusion (mean +/- SD = 9.1 +/- 6.1 vs. 0.1 +/- 3.2%, p < 0.05). The improved recovery in the felodipine group persisted throughout the observation period; %SS was 8.5 +/- 5.9% after 24-h reperfusion. No significant improvement was observed in the vehicle group after 24 h (%SS = 2.7 +/- 2.0%, p < 0.05). The area of the infarct was measured by triphenyl tetrazolium chloride staining. When expressed as percentage of the left ventricle, the infarct was smaller in the felodipine group (8.2 +/- 4.0%) than in the vehicle group (14.6 +/- 3.5%; p < 0.01). The corresponding values for infarct size expressed as percentage of the area at risk was 38.6 +/- 18.9% in the felodipine group and 69.8 +/- 6.7% in the vehicle group (p < 0.01). Peak plasma felodipine concentration was reached 30 min after onset of reperfusion (4.9 +/- 1.2 nM).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Granulocyte superoxide anion and elastase release during cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) is known to induce several pathogenic responses in cardiovascular surgery. To explore leukocyte activation during PCB, we investigated superoxide anion (O2-) production by granulocytes in 6 patients undergoing aortocoronary bypass surgery. O2- production was determined with chemiluminescence amplified by a cypridina luciferin analogue. Granulocytes collected from the blood in the arterial site of the CPB circuit were stimulated by phorbol myristate acetate, n-formyl-methionyl-leucyl-phenylalanine, and opsonized zymosan. All the stimulators failed to disclose a significant difference between the magnitude of chemiluminescence during and after CPB. However, significant complement activation was detected, and the plasma level of granulocyte elastase increased gradually during and after CPB. This discrepancy between the unchanged O2- production by stimulated granulocytes and the increase in inflammatory mediators including granulocyte elastase may be due to sequestration of activated granulocytes in extravascular tissues. Namely, it was highly likely that activated granulocytes responsible for the increased plasma elastase level were sequestered and remained outside the blood circulation.

Aged↗
PubMed1993

[Basic study of CA125 measurement using a newly developed "SD-8729" IRMA kit].

"SD-8729" is a one-step IRMA kit employing OC125 antibody as 125I-labeled tracer and M-11 antibody as an immunoadsorbent. Higher bound-radioactivity to beads was observed with shorter incubation time than that of a currently used CA125 IRMA kit which employed OC125 antibody both as 125I-labeled ligand and immunoadsorbent attached to beads. Almost identical CA125 values were obtained by using two kits. The antigenic nature recognized by the M-11 antibody seems substantially different from those of 130-22 or 145-9 antibodies recognizing CA130 antigen.

Antibodies, Monoclonal↗