Biomedical subjects

H Abe

Publications and source records attributed to H Abe.

At least 649 records · Page 36Linked to original sources

PubMed1995

Surgical treatment of childhood moyamoya disease--comparison of reconstructive surgery centered on the frontal region and the parietal region.

Indirect revascularization procedures centered on the parietal region, such as encephalo-myo-arterio-synangiosis (parietal synangiosis) and direct procedures centered on the frontal region using both the anterior and the posterior branches of the superficial temporal artery (STA), such as STA to middle cerebral artery anastomosis combined with encephalo-duro-arterio-myo-synangiosis (frontal anastomosis) were compared in childhood moyamoya disease patients. The parietal synangiosis group consisted of 10 sides in five patients, and the frontal anastomosis group consisted of 30 sides in 15 patients. The development of postoperative collateral circulation was assessed by external carotid angiography, the neurological outcome was monitored for 2 years after surgery, and the intelligence quotient (IQ) was measured at least 6 months after surgery. Frontal anastomosis achieved superior results compared to the parietal synangiosis assessed by development of collateral circulation, in particular to the orbitofrontal artery, the prefrontal artery, and the precentral artery (p < 0.01), and reduction in the incidence of ischemic attacks, such as transient ischemic attacks (p < 0.05). The mean IQ in the frontal anastomosis group was higher than that in the parietal synangiosis group. Vascular reconstruction centered on the frontal region utilizing both the anterior and posterior branches of the STA is more efficacious than only synangiosis centered on the parietal region.

Arteriovenous Anastomosis↗

PubMed1995

p55 and p75 tumor necrosis factor receptor expression on human glioblastoma cells.

Expression of the two types of tumor necrosis factor (TNF) receptor, p55 and p75, in 12 human glioblastoma cell lines was studied. Reverse-transcription polymerase chain reaction detected messenger ribonucleic acid (mRNA) transcripts of p55 TNF receptor in all 12 cell lines tested, but p75 TNF receptor mRNA in only four cell lines. Flow cytometric analysis with anti-p55 and anti-p75 TNF receptor monoclonal antibodies demonstrated both p55 and p75 proteins in these four cell lines, but the level of expression of p75 molecule was very low. Correlation of p55 and p75 TNF receptor expression with TNF-induced growth suppression and production of bioactive molecules (interleukin-6, interleukin-8, manganase-superoxide dismutase, prostaglandin E2) showed that p55 TNF receptor mediates these TNF actions, but none of the responses were influenced by the presence of the p75 TNF receptor, which apparently has no specific role.

Base Sequence↗

PubMed1995

CT diagnosis of early hepatocellular carcinoma: sensitivity, findings, and CT-pathologic correlation.

OBJECTIVE: The purpose of this study was to determine the sensitivity of CT in detecting early hepatocellular carcinoma and to evaluate its CT appearance. An early hepatocellular carcinoma is a nodular lesion with no fibrous capsule composed of well-differentiated tumor histologically. It differs from a small hepatocellular carcinoma, which is an overt tumor that is moderately to poorly differentiated and has a fibrous capsule. Size is not a criterion for distinguishing between early and small hepatocellular carcinomas. MATERIALS AND METHODS: Thirty-one patients with 39 histopathologically proved early hepatocellular carcinomas (mean diameter, 1.7 cm) found by sonography, MR imaging, and/or intraoperative sonography were included in a retrospective study. We reviewed unenhanced CT scans of the entire liver in 30 patients (37 lesions) and early and late (35 sec and 5 min after the beginning of injection of contrast material) contrast-enhanced CT scans of the entire liver in all 31 patients (table incremental CT in 21; helical CT in 10; 39 lesions). Eighteen histologically proved small hepatocellular carcinomas (< or = 3 cm; mean diameter, 2.3 cm), present in the same patients, served for comparison. Histopathologically, nine patients had chronic hepatitis, and 22 had cirrhosis. RESULTS: The overall sensitivity of CT in detecting early hepatocellular carcinoma was 56%. These tumors were usually isodense with respect to surrounding liver on unenhanced, early enhanced, and late enhanced CT scans (iso-iso-iso). This pattern was seen in 17 (46%) of 37 lesions; thus, these 17 histologically proved early hepatocellular carcinomas were not detected with CT. An iso-iso-low density pattern was recognized in eight (22%), a low-low-low pattern in seven (19%), and several different patterns in five (13%) of the 37 lesions. Only two (5%) of 39 early hepatocellular carcinomas had a high-density appearance on early enhanced CT scans. In comparison, the most common pattern of small overt hepatocellular carcinomas on CT scans was low-high-low, seen in 17 lesions (94%) detected with CT. When the density of lesions on unenhanced CT scans was compared with the histopathologic appearance of the masses, low-density lesions showed mild to moderate fatty change and isodense lesions showed no or minimal fatty change (p = .006). CONCLUSION: The sensitivity of CT in detecting early hepatocellular carcinoma is poor (56%). However, the diagnosis of early hepatocellular carcinoma should be considered if CT scans show a small lesion with an iso-low or low-low density enhancement pattern on early and late contrast-enhanced CT scans, respectively, in patients with chronic liver disease.

Aged↗

PubMed1995

A case of acute exacerbation of chronic hepatitis B accompanied by antibody to HBeAg with remission of liver damage after long-term treatment with interferon.

The patient was a 47-year-old female with chronic hepatitis B having antibody to HBe antigen (HBeAg). She was admitted to our hospital in March, 1994, because of acute exacerbation of chronic hepatitis B. Laboratory data revealed the elevated serum transaminase and DNA-polymerase levels, and decreased prothrombin activity. The histological examination of the liver showed chronic active hepatitis with severe hepatic necrosis. Point mutation of the precore region of HBV-DNA (pre-C mutant) was observed in clones from this case by polymerase chain reaction method. The patient was treated with recombinant interferon alpha-2a 9 MU daily for 2 weeks and thereafter 3 times weekly for 6 months. After interferon therapy, the pre-C mutant disappeared with the improvement of transaminase levels and prothrombin activity. These findings suggest the possibility that long-term treatment with interferon therapy is effective for the acute exacerbation of chronic hepatitis B accompanied by antibody to HBeAg.

Chronic Disease↗

PubMed1995

Structure-activity relationship of pamamycins: effects of alkyl substituents.

Nine new pamamycin homologues were isolated from the culture broth of Streptomyces alboniger IFO 12738 using a combination of ODS and NH2 HPLCs, and their structures determined by GC-MS. The structural differences in these homologues are in the numbers and positions of methyl and ethyl groups. The aerial mycelium-inducing and growth-inhibitory activities in S. alboniger of these homologues and their antibiotic activity against Bacillus subtilis were examined. The effects of the alkyl substituents on these activities are discussed.

Antifungal Agents↗

PubMed1995

[A case of surgical retrieve of migrated microcatheter].

This is a report of an accidental breakaway of a microcatheter during endovascular embolization for cerebral arteriovenous malformation occurring in a 48-year-old female. She had a sudden onset of cerebral herniated signs caused by a large hemorrhage in the region of the right parietal lobe. An angiogram showed a large arteriovenous malformation in the same region. 48 days after emergency evacuation of the hematoma and clipping of a feeding artery, we performed endovascular embolization using a microcatheter as assistant therapy for total removal of the nidus. However, accidentally, the microcatheter broke and migrated to the distal middle cerebral artery. Although we tried to retrieve the catheter using a loop snare, we had no success. We eventually retrieved it by open surgery next day. Fortunately the migrated catheter could be seen through a cortical artery, so after trapping it by using elastic thread and cutting off the artery we were able to extract the migrated catheter. Finally we were able to remove the nidus totally without other complications. Since breaking and migration of a microcatheter is a rare but possible accident, we should be prepared to cope with it appropriately.

Catheterization↗

PubMed1995

[Effects of combined aprotinin and prostagrandin E1 therapy on aortic arch replacement].

This study was undertaken to compare the effects of combined aprotinin and prostaglandin E1 therapy on aortic arch replacement. Twenty patients were divided into 2 groups with (group A; n = 10) or without (group B; n = 10) the treatment (200 KIU of aprotinin and 0.01-0.02 microgram/kg/min of prostaglandin E1 during cardiopulmonary bypass (CPB) and the first postoperative day. Preoperative evaluation of respiratory function and all parameters related to CPB procedure were revealed to be equal between the groups. Postoperative A-a DO2 and respiratory index (RI) as functional parameters of oxygenation capacity, dosage of dopamine were monitored at 0, 3, 6, 12, 18 and 24 hr after termination of CPB and at extubation period. Serum creatinine, platelet numbers and blood coagulation function (PT, APTT) were also assayed postoperatively. The recovery of respiratory and cardiac function were superior in group A with treatment, but renal and blood coagulation function showed no difference in the groups. We suggest the combined therapy with aprotinin and prostaglandin E1 for aortic arch replacement may emerge as a valuable treatment to save postoperative respiratory and cardiac function.

Alprostadil↗

PubMed1995

Endothelial cell injury induced by plasmin in vitro.

We investigated the effect of plasmin on the integrity and function of endothelial cells to elucidate the mechanism by which bleeding or rethrombosis may be induced in thrombolytic therapy. When incubated with cultured human umbilical vein endothelial cells (HUVECs), plasmin increased the endothelial permeability to serum albumin 10 minutes after the incubation. Plasmin damaged the cell membranes 30 minutes after the incubation, detached the cells from the matrix 3 hours after the incubation, and finally induced cell lysis. Such damaging effects on HUVECs were not observed with plasminogen or plasmin pretreated with aprotinin and alpha 2-plasmin inhibitor, suggesting that the catalytic function of plasmin plays an important role in inducing this damage. Sulfur 35-labeled glycosaminoglycans (35S-GAGs) of HUVECs were decreased 1 hour after the incubation of plasmin with HUVECs, and the thrombomodulin (TM) activity of HUVECs measured by protein C activation capacity was decreased 6 hours after the incubation. Neither 35S-GAGs nor the TM activity of HUVECs was decreased after the incubation of plasmin pretreated with aprotinin and alpha 2-plasmin inhibitor. These findings suggest that the nonthrombogenic properties of endothelial cells can be damaged by the proteolytic action of plasmin. Our findings, taken together, suggest that plasmin damages the endothelial barrier function, endothelial cell integrity, and nonthrombogenic properties. These damaging effects of plasmin on endothelial cells may be related to the pathophysiology of bleeding or rethrombosis observed in patients undergoing high-dose thrombolytic therapy for thrombosis.

Cell Membrane Permeability↗

PubMed1995

JTP-4819: a novel prolyl endopeptidase inhibitor with potential as a cognitive enhancer.

JTP-4819 ((S)-2-[[(S)-2-(hydroxyacetyl)-1-pyrrolidinyl]carbonyl]-N- phenylmethyl)-1-pyrrolidinecarboxamide) is a potent (IC50: 0.83 +/- 0.09 nM in rat brain supernatant; 5.43 +/- 0.81 nM in Flavobacterium meningosepticum) and specific inhibitor of prolyl endopeptidase (PEP). JTP-4819 (3 mg/kg p.o.) exhibited a strong and durable ex vivo inhibitory effect on PEP in various regions of the rat brain. In addition, JTP-4819 inhibited the degradation of substance P, arginine-vasopressin, thyrotropin-releasing hormone, neurotensin, oxytocin, bradykinin, and angiotensin II by purified PEP with IC50 values of 9.6, 13.9, 10.7, 14.0, 4.5, 7.6 and 10.6 nM, respectively. In the one-trial passive avoidance test in rats with scopolamine-induced amnesia, JTP-4819 significantly prolonged the retention time when administered orally at doses of 1 and 3 mg/kg 1 hr before acquisition or at 3 and 10 mg/kg 1 hr before retention. In addition, coadministration of JTP-4819 and substance P, arginine-vasopressin or thyrotropin-releasing hormone (at doses at which each drug alone did not prolong the retention time) improved the retention time of rats with scopolamine-induced amnesia. Microdialysis studies demonstrated that JTP-4819 caused a significant increase in ACh release in the frontal cortex and hippocampus of young rats at oral doses of 1 and 3 mg/kg, as well as in both brain regions of aged rats at a dose of 3 mg/kg. These results indicate that JTP-4819 potentiates neuropeptide functions inhibiting PEP, that it activates cholinergic transmission and that it enhances learning and memory.

Acetylcholine↗

PubMed1995

[Pharmacokinetics of SK & F 104864 in experimental animals. I. Plasma level].

A camptothecin derivative, SK & F 104864 (topotecan), was injected for 30 minutes into the rabbit ear vein at a dose of 2 mg/kg or 5 mg/kg, and the plasma concentration was assayed by a HPLC method. The plasma level of SK & F 104864 (lactone form) decreased bi-exponentially with mean alpha and beta half-lives of 0.101 h and 0.849 h at 2 mg/kg, respectively, and 0.518 h and 7.57 h at 5 mg/kg, respectively. The AUCs were 0.846 micrograms.h/ml at 2 mg/kg and 2.14 micrograms.h/ml at 5 mg/kg. The plasma level of total topotecan (SK & F 104864 plus SK & F 105992) decreased bi-exponentially with mean alpha and beta half-lives of 0.696 h and 9.07 h at 2 mg/kg, respectively, and 0.795 h and 8.97 h at 5 mg/kg, respectively. The AUCs were 2.15 micrograms.h/ml at 2 mg/kg and 5.73 micrograms.h/ml at 5 mg/kg. The AUCs of lactone form were 39.3% of total topotecan at the 2 mg/kg dose and 37.3% at the 5 mg/kg dose, respectively. After intravenous bolus injection of SK & F 104864 at 20 mg/kg into Sarcoma 180 bearing mice, the alpha and beta half-lives of SK & F 104864 were 0.401 h and 3.99 h, respectively, and the AUC was 5.49 micrograms.hr/ml. The alpha and beta half-lives of total topotecan were 0.517 h and 4.27 h, respectively, and the AUC was 9.88 micrograms.hr/ml. The ratio of lactone form to total topotecan was 55.6%.

Animals↗

PubMed1995

[Pharmacokinetics of SK & F 104864 in experimental animals. II. Tissue distribution].

After intravenous bolus injection of a camptothecin derivative, SK & F 104864 (topotecan), at 20 mg/kg into Sarcoma 180 bearing mice, the tissue concentration of total topotecan (SK & F 104864 plus SK & F 105992) in the mice decreased bi-exponentially, and the beta half-lives in most tissues were longer than those in plasma. The AUCs of total topotecan were extremely large in the kidney, that was followed by the pancreas > intestine > stomach > spleen > liver > thymus > lung > tumor > uterus > plasma. The concentration of total topotecan after 24 hours decreased to less than 2% of the peak level in most tissues except the kidney.

Animals↗

PubMed1995

Extensive subcutaneous emphysema and hypercapnia during laparoscopic cholecystectomy: two case reports.

We report two cases of marked hypercapnia of more than 60 mm Hg (PaCO2) and extensive subcutaneous emphysema noted during laparoscopic cholecystectomy. The first case, a 55-year-old man was diagnosed as having cholecystolithiasis and had hypercapnia up to 83.5 mm Hg (PaCO2) during laparoscopic cholecystectomy. The patient resumed spontaneous respiration under controlled ventilation accompanied by persistent bigeminal pulse. Soon after deflation, CO2 returned to normal range, and extensive subcutaneous emphysema was detected in the recovery room. The second patient, a 53-year-old woman, had cholecystolithiasis and also underwent laparoscopic cholecystectomy. Both hypercapnia rising to 61.1 mm Hg (PaCO2) and extensive subcutaneous emphysema appeared just before completion of resection of the gallbladder. Mild hypercapnia during pneumoperitoneum of about 50 mm Hg (PaCO2) has been reported previously. As compared with cases in the literature, the present cases suggest that hypercapnia is due to extensive subcutaneous emphysema. The large absorption surface area in the subcutaneous tissue and the large difference in the partial pressure cause the extensive gaseous interchange of CO2 between subcutaneous tissue and blood perfusing into it at the moment between peritoneal cavity and blood perfused the peritoneum.

Carbon Dioxide↗

PubMed1995

[Effect of ulinastatin on the free radical during cardiopulmonary bypass].

Cardiopulmonary bypass (CPB) involves many factors for generating free radicals. It is difficult to detect free radical directly in clinical situations. Vitamin E is recognized as an intrinsic radical scavenger. We examined the change of vitamin E level to prove indirectly the evidence of free radical generation during CPB. Moreover, we investigated the effect of ulinastatin on the free radical during CPB by determining the vitamin E level. Twenty patients who received cardiac surgery were divided into the membrane oxygenator group and the bubble oxygenator group. In each group, five patients received 12,000 units.kg-1 of ulinastatin 15 min after starting CPB. Blood samples were obtained 15 min after starting CPB and 15 min after reperfusion of coronary artery. In the bubble oxygenator group without ulinastatin, vitamin E level at reperfusion phase decreased significantly compared with that at the start of CPB. In the bubble oxygenator group with ulinastatin, vitamin E level at reperfusion phase showed no decrease compared with the level at the start of CPB. In the membrane oxygenator group, there was no significant change in vitamin E level. Therefore, we suspect that a decrease of vitamin E during CPB with bubble oxygenator demonstrates the evidence of free radical generation and these results suggest that ulinastatin may scavenge free radicals during CPB.

Adult↗

PubMed1995

[The effect of nicorandil on the neuromuscular block induced by vecuronium].

The effect of nicorandil on the neuromuscular block induced by vecuronium was investigated in vitro with rat phrenic nerve-hemidiaphragm preparation. Both single twitch (ST) and train-of-four ratio (TOFR) elicited with indirect electrical stimulation were used. The administration of nicorandil alone showed no effects on ST and TOFR. The pre-administration of nicorandil exerted significant depressing effect on ST compared with vecuronium alone. High concentration of nicorandil (4 x 10(-6) M) produced more significant effect on ST compared with low concentration of nicorandil (10(-7) M). In this study, the nicorandil showed similar effect as calcium antagonists on neuromuscular blockade.

Animals↗

PubMed1995

[Responses of TNF alpha, IL-8, and leukocyte adhesion molecule CD18 to cardiopulmonary bypass].

To evaluate the inflammatory response to the cardiopulmonary bypass, we investigated the serum levels of tumor necrosis factor alpha (TNF alpha), interleukin 8 (IL-8), and the expression of leukocyte adhesion molecule CD18. Six patients who underwent elective coronary artery bypass grafting were studied. TNF alpha was elevated significantly 30 minutes after the start of CPB and returned to the baseline 60 minutes after CPB. IL-8 increased significantly after the start of CPB and reached a peak at 10 minutes after release of the aortic cross-clamp, remaining significantly elevated until 10 minutes after the end of CPB (P < 0.05). Circulating neutrophil count and granulocyte elastase increased significantly 10 minutes after release of the aortic-cross clamp and remained high until the first postoperative day. The increase of the neutrophil CD18 expression was not observed. This study demonstrates elevated TNF alpha and IL-8 levels during CPB followed by increases of the neutrophil and the granulocyte elastase, which may be of importance in the systemic inflammatory response to CPB, especially in the development of postperfusion lung injury.

CD18 Antigens↗

PubMed1995

[Antegrade or retrograde blood cardioplegic method: comparison of postsurgical right ventricular function and conduction disturbances].

This study was undertaken to compare postsurgical right ventricular function and the occurrence of conduction disturbances after employing cold blood antegrade or retrograde cardioplegia during open heart surgery. Thirty-four patients were divided into AC (antegrade) and RC (retrograde) groups for the difference of route for delivery of cardioplegic solutions. Preoperative evaluation of cardiac and respiratory function revealed to be equal characteristics between the groups. Postoperatively, A-aDO2 and respiratory index (RI) as functional parameters of oxygenation capacity, LVSWI, RVSWI, dosage of dopamine and conduction disturbances were monitored at 0, 3, 6, 12 hours after termination of cardiopulmonary bypass and at extubation period. Although the recovery of respiratory function and left ventricular function were similar in both groups, temporal suppression of right ventricular function was indicated in RC group during early period after surgery, and then recovered to the same values of AC group within 3 hours. In RC group, several type of conduction disturbances were detected in 28 per cent of patients. But none of the persistent conduction disturbances were remained in all patients. We suggest retrograde coronary sinus perfusion may emerge as a valuable alternative to antegrade methods for delivery of cardioplegia.

Blood↗

PubMed1995

[Matrix metalloproteinase in the cynomolugus monkey optic nerve heads].

Gelationolytic and caseinolytic activity of matrix metalloproteinase in normal cynomolugus monkey optic nerve heads was investigated. Optic nerve heads of three eyes were incubated in the media for 20 hours. Each media was applied to the gelatin or casein containing gels, and zymography was performed. Major bands of 94 kDa and 62 kDa gelatinase activities were demonstrated in all three eyes. In one eye gelatinolytic activity of the 58 kDa band was also demonstrated. Caseinase activity was not detected in any of the three optic nerve heads.

Animals↗

PubMed1995

[Functional magnetic resonance imaging of the human primary visual cortex during visual stimulation].

Signal changes in the human primary visual cortex during visual stimulation were evaluated using non-invasive functional magnetic resonance imaging (fMRI). The experiments were performed on 10 normal human volunteers and 2 patients with homonymous hemianopsia, including one who was recovering from the exacerbation of multiple sclerosis. The visual stimuli were provided by a pattern generator using the checkerboard pattern for determining the visual evoked potential of full-field and hemifield stimulation. In normal volunteers, a signal increase was observed on the bilateral primary visual cortex during the full-field stimulation and on the contra-lateral cortex during hemifield stimulation. In the patient with homonymous hemianopsia after cerebral infarction, the signal change was clearly decreased on the affected side. In the other patient, the one recovering from multiple sclerosis with an almost normal visual field, the fMRI was within normal limits. These results suggest that it is possible to visualize the activation of the visual cortex during visual stimulation, and that there is a possibility of using this test as an objective method of visual field examination.

Adult↗