PubMed Health⌕ Search

Biomedical subjects

H Akimoto

Publications and source records attributed to H Akimoto.

At least 19 recordsLinked to original sources
PubMed1992

Thoracic aortic operations in patients aged 70 years or older.

Thirty-one patients over the age of 70 years (group A) and 72 patients less than 69 years (group B) underwent a variety of thoracic aortic surgical procedures. Early and long-term results and cerebral function were compared between the two groups. Preoperative and postoperative cerebral function was evaluated using mini mental state-Himeji and Wechsler adult intelligence scale tests. The operative mortality of groups A and B was 12.9% and 11.1%, respectively (not significant). There were no significant differences in postoperative complications between the two groups. The late mortality rates of groups A and B were 11.1% and 9.3%, respectively (not significant). There were no significant differences between the two groups in the mini mental state-Himeji test, digit symbol, vocabulary, and total Wechsler adult intelligence scale scores before and after operation. We conclude that thoracic aortic surgical procedures in patients over 70 years of age can be performed with acceptable mortality and morbidity risks. Most patients showed symptomatic improvement.

Adult↗
PubMed1992

[Treatment of gastric ulcers with proton pump inhibitors--long-term treatment].

Pronounced inhibition of acid secretion appears to induce an intragastric environment suitable for N-nitrosamine formation, hyper-gastrinemia, ECL cell hyperplasia and carcinoid tumor formation. Development of gastric cancer, however, has not been obvious in clinical and experimental studies, but oncongenicity studies indicate an increased risk of gastric cancer with long-term use of proton pump inhibitors in subjects with hyperplastic or other, changes in the gastric mucosa. The findings suggest that proton pump inhibitors should be used only for short term treatment.

Adenosine Triphosphatases↗
PubMed1992

[Problems in ulcer surgery after the introduction of H2-receptor antagonists].

Recently, antisecretory drugs such as H2-receptor antagonists (H2-RA) or proton pump inhibitor have been used for peptic ulcer patients widely in Japan. However, there are possibilities that long term administration of H2-RA might cause changes in intragastric environment. The present study was designed to clarify the changes of surgical treatment in Japan Surgical Society training hospitals, before and after introduction of H2-RA. Serum gastrin and antral G-cell number was measured after administration of H2-RA (1 mg/kg 14 days continuous infusion) in rat. Also, acid secretion and gastrin response stimulated by adrenalin (40 ng/kg.min) were measured in duodenal ulcer patients. 1) In the view of surgical treatment, elective operation highly decreased after the introduction of H2-receptor antagonists, and showed the increase of the rate of emergency operation up to 70%. 2) Hypergastrinemia and antral G cell hyperplasia were observed after administration of H2-RA in rats. 3) Acid secretion stimulated by adrenalin which is considered as antral G cell dependent, showed a higher response in H2-RA treated cases than in those untreated. 4) Antrectomy was carried out in 43.4% of the patients treated with H2-RA versus 18.9% to the patients untreated.

Animals↗
PubMed1992

[Result of surgical treatment of true or dissected thoracic aneurysm: determinants analysis in operative mortality and morbidity].

Between 1986 and 1990, 69 patients underwent surgery either for thoracic aneurysm (27 patients) or aortic dissection (42 patients). Sixty one patients (88%) survived and 8 patients (12%) died after surgery. Main determinants of deaths in 4 patients with true arch aneurysm were bleeding from the sites of aortic clamping or anastomosis and intraoperative severe LOS. Three patients with acute type A dissection died from bleeding due to clamp injury or myocardial ischemia. The cause of death in the patient with chronic type B dissection was associated with brain damage due to hypoxia developed during left heart bypass. Postoperative cardiac, pulmonary, hepatic and renal functions were analyzed in the operative survivors. Cardiac functions were maintained well in all patients except two patients with chronic type A dissection. Four patients, one with true arch aneurysm, 2 with chronic type A and one with chronic type B dissection, required tracheostomy. The mean of maximum total serum bilirubin exceeded 4 mg/dl in the patients with true arch aneurysm, acute and chronic type A dissection. The level of serum creatinine showed slight increase in all patients but prophylactic peritoneal dialysis was performed in one patient with chronic type A dissection. In conclusion, the cause of deaths in most patients with thoracic aneurysm was due to inappropriate operative techniques and circulatory supports during surgery. Without the complication described above, the patients could tolerate surgery well.

Aged↗
PubMed1992

[Postoperative respiratory dysfunction in patients with Stanford type A aortic dissection].

Between 1986 and 1990, 24 patients with Stanford type A dissection (acute; 14, chronic; 10) underwent surgery through median sternotomy. The patients were divided into two groups by a duration of postoperative ICU stay for respiratory care. Six patients in the long-period group stayed in ICU for more than 15 days and 18 patients in the short-period group stayed for less than 15 days after surgery. Acuity of disease, age, sex, operation time, pump time, aortic clamp time, lowest esophageal temperature, amount of blood transfusion, arch manipulation for cerebral perfusion with or without arch reconstruction, occurrence of phrenic nerve palsy and other postoperative complications, postoperative cardiac, hepatic and renal functions were compared between two groups. Conclusions are as follows: 1) Arch manipulation for cerebral perfusion with or without arch reconstruction, phrenic nerve palsy, other complications (pericardial and pleural fluid accumulation, recurrent nerve palsy, postoperative bleeding and coronary spasm) and high serum creatinine level were main factors for prolonged postoperative ICU stay for respiratory care and 2) arch manipulation in the patients with chronic type A aortic dissection induced high incidence of phrenic nerve palsy.

Adult↗
PubMed1991

Induction of differentiation of human myeloid leukemia HL-60 cells by novel nonphosphorus alkyl ether lipids.

We synthesized a new series of nonphosphorus alkyl ether glycerolipids, in which the 2-acetyl group of platelet-activating factor was replaced by a pyrimidin-2-yl group and the 3-phosphocholine portion by an omega-(substituted ammonio)ethoxyethyl side-chain including omega-thiazolio-, imidazolio- and pyridinio groups with or without a carboxyl substituent, respectively (compound I-XI). Their effects on cell proliferation and differentiation of human myeloid leukemia HL-60 cells were examined. Incubation of HL-60 cells with these cationic and zwitterionic alkyl ether lipids inhibited proliferation of HL-60 cells with IC50 values ranging from 10 to 500 ng/mL. The cells were induced by the lipids to differentiate into morphologically and functionally mature granulocytes. Among the compounds we tested, 1-octadecyl-2-pyrimidinyl-3-[3-(5- carboxylatepentyl)imidazolioethoxyethyl]glycerol (compound I) was the most effective in inducing differentiation of HL-60 cells. Compound I showed on a molar basis, an inhibitory effect on the leukemic cells over 50 times greater than did 2-(2-dodecyloxyethoxy)ethyl 2-pyridinio-ethyl phosphate, the antileukemic alkyl ether phospholipid.

Antineoplastic Agents↗
PubMed1991

Evaluation of mRNA levels by the polymerase chain reaction in small cardiac tissue samples.

Doxurubicin is an effective and widely used chemotherapeutic agent. However, use of this drug is often limited by its cardiotoxic side effects. We have observed that an early event accompanying doxorubicin cardiomyopathy is a selective decrease in levels of muscle gene transcripts in cardiac tissue (Ito et al., Proc. Natl. Acad. Sci. USA 87: 4275-4279). Since this decrease precedes ultrastructural evidence of cardiac damage, measurements of muscle transcripts might assist in the clinical evaluation of doxorubicin cardiotoxicity. We have therefore assessed the utility of the polymerase chain reaction in the measurement of mRNA in control and doxorubicin-treated animals. These measurements were performed on small tissue samples that simulate endomyocardial biopsies. We measured cardiac alpha-actin transcripts as a fraction of ferritin heavy chain transcripts using the method described by Chelly et al. (Nature 333: 858-860, 1988). 0.5 micrograms of total RNA, an amount equivalent to that obtainable from a typical endomyocardial biopsy, was efficiently co-amplified with cardiac alpha-actin and ferritin heavy chain specific primers. The cardiac alpha-actin/ferritin heavy chain ratio calculated from the PCR results correlated well (R = 0.981) with results obtained using Northern blot analysis of 10 micrograms RNA. The correlation was maintained over a wide range of cardiac alpha-actin transcript abundance. These results show that mRNA from cardiac tissue can be estimated by the polymerase chain reaction, even from a small, endomyocardial biopsy-sized sample.

Actins↗
PubMed1991

Novel pyrrolo[2,3-d]pyrimidine antifolates: synthesis and antitumor activities.

New antifolates, characterized by a 6-5 fused ring system, a pyrrolo[2,3-d]pyrimidine ring, and a trimethylene bridge at position 5 (12a,b and 13a,b) were designed and efficiently synthesized. The synthetic method included (1) construction of the key intermediary acyclic skeleton, 5-[4-(tert-butoxycarbonyl)phenyl]- 2-(dicyanomethyl)pentanoates (6a,b), (2) cyclization with guanidine, followed by reduction to the pyrrolo[2,3-d]pyrimidine derivatives (8a,b and 9a,b), and (3) subsequent glutamate coupling and saponification. These antifolates were more growth-inhibitory by about 1 order of magnitude than methotrexate (MTX) against KB human epidermoid carcinoma cells and A549 human nonsmall cell lung carcinoma cells in in vitro culture. Growth inhibitory IC50 values for N-[4-[3-(2,4-diamino-7H-pyrrolo[2,3-d]pyrimidin-5- yl)propyl]benzoyl]-L-glutamic acid (12a) against KB and A549 were 0.27 and 4.5 ng/mL, while those for MTX were 5.0 and 35 ng/mL, respectively. Other members of this class of antifolates, 12b and 13a,b, showed good activities nearly equal to that of 12a.

Antineoplastic Agents↗
PubMed1991

Effects of pirmenol on electrical induction of sustained ventricular tachycardia in a seven-day-old canine myocardial infarction.

Effects of pirmenol on electrical induction of sustained ventricular tachycardia (VT) were examined in 14 dogs with 7-day-old myocardial infarctions. Before administration of the drug, sustained VT was induced in 8 of 14 dogs. After administration of 3 mg/kg pirmenol, induction of VT was suppressed in 2 dogs but remained inducible in 6 dogs. After cumulative administration of 5 mg/kg pirmenol, VT was no longer inducible in 3 dogs but in the other 3 dogs VTs were still inducible at increased cycle lengths. After 7 mg/kg pirmenol, VT was not inducible in the remaining three dogs. Arrhythmias could not be provoked in any postinfarction dogs after pirmenol administration. Plasma concentrations after sequential and cumulative administration of 3, 5, and 7 mg/kg pirmenol averaged 0.43, 0.65, and 1.15 micrograms/ml, respectively. Administration of pirmenol increased the effective refractory period (ERP) and paced QRS duration in both the normal and infarcted ventricular myocardium. In the infarcted myocardium, prolongation of the ERP for the second and third extrastimuli was greater than for the first one (p less than 0.05). Results indicate that pirmenol is effective for prevention of sustained VT owing to prolongation of both the ERP and conduction time in recent myocardial infarction.

Animals↗
PubMed1991

[Analysis of hepatic and renal dysfunction after surgery of thoracic aneurysm].

To analyze causes of postoperative hepatic and renal dysfunction in patients with thoracic aneurysm, we examined 31 patients who survived surgeries and 2 patients died of MOF. The patients were separated into three groups as follows; Cardiopulmonary bypass (CPB) was used for circulatory support in group A (n = 7), CPB and low flow perfusion during open distal anastomosis in group B (n = 13) and temporary bypass or left atrial distal aorta arterial bypass was used in group C (n = 11). Operation time was significantly longer in group A (9.8 hrs) compared with group C (6.1 hrs). Amount of intraoperative blood transfusion was greater in groups A (4980 ml) and B (4860 ml) compared with group C (2320 ml). Postoperative highest total bilirubin level was significantly greater in group A (7.8 mg/dl) than group C (2.5 mg/dl). LDH was higher in groups A (1322 IU/l) and B (1336 IU/l) than group C (991 IU/l). GOT was higher in group B (200 IU/l) than group C (64 IU/l). There were no significant differences in GPT, creatinine and BUN among the three groups. Operation time and amount of intraoperative blood transfusion were positively correlated with postoperative hepatic function parameters. Two patients died of MOF showed severe hepato-renal dysfunction associated with LOS. The results indicate that hypothermic low flow perfusion during open distal anastomosis do not induce hepatic or renal dysfunction, and postoperative hyperbilirubinemia is resulted from bilirubin overload which patients can tolerate well if they are not complicated with MOF.

Aged↗
PubMed1979

[Computed tomography in crossed aphasia (author's transl)].

Crossed aphasia, first described by Bramwell, is aphasia due to the hemispheric damage on the side of handedness. Crossed aphasia in a dextral is rare, and in Japan, there have not been more than ten cases in which the lesion is localized clearly. The cases reported till now have been verified mainly by necropsy. However, the time lag between the appearance of aphasia and the necropsy may affect the conclusion subtly. We consider that computed tomography (CT) can obtain almost the same findings as that by necropsy. However, at present there have been few cases diagnosed by CT except two cases reported by April et al. and Wechsler. We have reported a 47-year-old man in a dextral, who shows left hemiparesis and Broca's aphasia. His lesion is diagnosed by cerebral angiography and CT as the right hemisphere infarction due to right middle cerebral artery occlusion. CT localizes the lesion on the right hemisphere mainly sited deep region and sited wedge shaped cortical area of the fronto-parietal region. On the other hand, it localizes no lesion on the left hemisphere. CT in aphasia has been already reported by Hayward et al. In their report they concluded that correlation of lesion located by CT with aphasia type supported Geschwind's concept of aphasia. In this report we have discussed CT in crossed aphasia analysing our case and the two cases by April et al. and Wechsler. Three cases including our case are all Broca's aphasia, and we compare the lesion location of these three cases with Hayward's lesion located on Broca's aphasia. As the result of this, we can draw the conclusion that the lesion location by CT of these three cases and that of Hayward's report are almost symmetric.

Aphasia↗
PubMed1979

[Computed tomography in metastatic brain tumors and meningeal carcinomatosis (author's transl)].

The computed tomogrpahy has been proved to be highly reliable in diagnosis of CNS diseases. The findings in 26 cases of metastatic brain tumors, and 2 cases of meningeal carcinomatosis performed with Hitachi CT-H scanner are analized. Metastatic tumors are seen on plain CT as mainly isodense nodules (60%). But, on enhanced CT, they increase in their density (97%). Larger nodules of metastatic tumors (over 2 cm in diameter) are tend to contain less dense central area, so called central cavitation. The direction of the expansion and/or extension of the perifocal low density is characteristic to the location of the tumor. In cases of meningeal carcinomatosis, diffuse periventricular higher density can be recognized enhanced CT.

Adult↗
PubMed1979

[Roentgenological aspect of the basilar artery and its significance in clinical diagnosis--angiographical study a of the basilar artery (author's transl)].

Topometric study of basilar arteries was performed, using 130 normal vertebral angiograms of cases consisting of 83 males and 47 females aged 2 to 67 (mean = 38.1). The cases having clinically and/or neuroradiologically had obvious positive findings such as cerebral atrophies, cerebrovascular diseases and space-taking lesions were excluded. Selective vertebral angiography using Seldinger's technique in 120 cases and retrograde brachial angiography in remaining 10 cases was carried out. The following results were obtained. 1) The position of vertebrobasilar junction was almost at the midline in frontal view with a mean distance of 0.3 mm +/- 3.6 leftward from the midline. 2) The length of basilar artery was 25.5 mm +/- 6.6 in frontal view and 32.8 mm +/- 5.8 in lateral view. 3) The position of basilar bifurcation was almost at the midline in frontal view with a mean of 0.0 mm +/- 2.0 from the midline, and 9.3 mm +/- 4.7 above the Twining's line and 24.5 mm +/- 3.4 posterior from tuberculum sellae in lateral view. 4) As for the configulation of basilar artery in frontal view, 'straight type' was common in young age and 'curved type' in old age. 'Curved type' was divided into four subtypes. The concave rightwards curved type and/ or the reversed S-formed tortuous type were almost twice many as the concave leftwards curved type and/or the S-formed tortuous type. This result seemed to support the reports on the hemodynamic mechanism of verteral arteries that the dominant flow was present on the left side at the rate of 50 to 80%. 5) Internal diameter of basilar artery at the point of 1 cm proximal to the apex was measured. The mean value was 3.3 mm +/- 0.6 in frontal view and 3.2 mm +/- 0.5 in lateral view. Maximum diameter of basilar artery was 3.5 mm +/- 0.7 in frontal view and 3.6 mm +/- 0.6 in lateral view.

Adolescent↗
PubMed1978

A new cephalosporin. SCE-963: 7-[2-(2-aminothiazol-4-yl)-acetamido]-3-[[[1-(2-dimethylaminoethyl)-1h-tetrazol-5-yl]-thio]methyl]ceph-3-em-4-carboxylic acid. Chemistry and structure-activity relationships.

The synthesis and the in vitro and in vivo antimicrobial activities of a series of 7-[2-(2-aminothiazol-4-yl)acetamido]cephalosporins (1) having varied 3-substituents, such as methyl, hydroxymethyl, acetoxymethyl, pyridiniomethyl and heterocyclicthiomethyls, are described. The derivatives having five membered heterocyclicthiomethyls exhibited strong inhibitory activities against Gram-negative organisms including some strains of Escherichia coli and Proteus morganii which are insensitive to cefazolin and cephaloridine. Pronounced activities were noted with 7-[2-(2-aminothiazol-4-yl)-acetamido]-3-[[[1-(2-dimethylaminoethyl)-1H-tetrazol-5-yl]thio]methyl]ceph-3-em-4-carboxylic acid (1y; SCE-963).

Animals↗
PubMed1978

[Falx images on CT scan (author's transl)].

It has been reported that falx images usually are not visualized on CT scan except in the case with brain atrophy of falx calcification. But we have often experienced the falx images on CT scan in the case of normal child, and we have an idea that falx images do not always mean a calcification of the falx. Evaluation of falx images on CT scan was done in 964 normal or abnormal cases in relation to different CT slice level, age, sex, pineal body and habenula and choroid plexus. Results are as follows; 1) Slice of higher level revealed higher incidence of falx image. 2) Incidence of falx images was lowest in the second decade, and showed gradual increase in relation to aging process. 3) Incidence of falx images revealed no sex difference. 4) Incidence of falx images showed a following tendency: a) Under 10 years; falx greater than pineal body and habenula greater than choroid plexus. b) Between 11 years to 20: pineal body and habenula greater than choroid plexus greater than or equal to falx. c) Over 21 years: pineal body and habenula greater than choroid plesus greater than falx. 5) The case with brain edema showed a higher incidence of falx images than the normal case, but the case with brain atrophy did not show a higher incidence. 6) Difference of CT number of falx region between the case of positive falx image and negative could not be recognized.

Adolescent↗