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Biomedical subjects

H Akashi

Publications and source records attributed to H Akashi.

At least 19 recordsLinked to original sources

Partial brachiocephalic perfusion under hypothermic cardiopulmonary bypass. An experimental study.

We studied electrophysiological, oxygen metabolic, and histological variables in dogs to establish the reliability and safety of partial brachiocephalic perfusion (PBP) under hypothermic cardiopulmonary bypass (CPB) at 23 degrees-25 degrees C. Sixteen mongrel dogs were divided into two groups. Six (control group) underwent typical hypothermic CPB for 90 min, and 10 (PBP group) underwent PBP under hypothermic CPB for 90 min. During core cooling on the CPB, a progressive reduction in voltage and slowing of frequency of the electroencephalogram (EEG) was observed. At around 23 degrees C nasopharyngeal temperature the tracing became almost flat and remained so throughout the hypothermic CPB or the PBP under hypothermic CPB. Consistent recovery of the EEG was, however, observed during the period of rewarming on the CPB, and the voltage and frequency of the EEG recovered to control levels on weaning off CPB at 36 degrees C in both groups. In the PBP group, the cerebral arteriovenous oxygen (AVO2) difference was 12.4 +/- 4.0 vol% before beginning the CPB, and it was 5.6 +/- 2.7, 5.7 +/- 3.1, 5.4 +/- 3.3, and 4.9 +/- 2.9 vol% at 10, 30, 60, and 90 min respectively after commencement of the PBP under hypothermic CPB. The cerebral AVO2 difference measured 10 min after commencement of the PBP was significantly less than that in the control group (P less than 0.05), but otherwise there were no significant differences between cerebral AVO2 differences in the two groups. Concentration of serum creatine kinase-BB (CK-BB) gradually increased in proportion to the duration of CPB in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

An index for proportion of head size to body mass during infancy.

The index "head circumference (cm)3/body weight (g)" gave an almost constant average (about 10) and standard deviation (about 1) in more than 2000 children at birth and at 4, 10, and 18 months. Application of this index to the data previously published confirms that the average is almost constant throughout the period from birth to 18 months, irrespective of sex or race. Head circumference cubed and body weight correlate significantly. This index seems to be useful to assess the proportion of head size to body mass during infancy, and to contribute to early diagnosis of diseases such as hydrocephalus or microcephaly.

Body Mass Index

Characterization of Japanese isolates of Aujeszky's disease virus by restriction endonuclease cleavage patterns, virulence in mice and thymidine kinase activity.

Twenty four cloned isolates of Aujeszky's disease virus collected from outbreaks of Aujeszky's disease from 1981 through 1989 in Japan were characterized by their restriction endonuclease (RE) cleavage patterns, virulence for mice and thymidine kinase (TK) activity. All of the isolates belonged to Type II of the four types classified by Herrmann et al. (1984). Based on the number and migration rate of the restriction fragments, the isolates were divided into 7 groups with Bam HI, 9 groups with Kpn I, 3 groups with BstE II and 2 groups with Sal I. The results indicate that the RE analysis, especially with Bam HI and Kpn I, provides useful epidemiological information about field isolates of Aujeszky's disease virus. All of the isolates showed virulence for mice ranging from 6.9 to 63.0 (PFU/LD50). It was interesting that the Nagano S87 strain, which had the highest virulence for the mouse, showed unique RE cleavage patterns with four enzymes. On the other hand, ara-T-resistant, TK-negative strain, was avirulent for mice (greater than 10(6.4) PFU/LD50). All of the isolates investigated in this study showed TK activity by the thymidine plaque autoradiography.

Animals

Spontaneous rupture of the ascending aorta.

A case of spontaneous non-traumatic rupture of the thoracic aorta in a hypertensive patient is presented. The clinical findings suggested acute aortic dissection, and a large pericardial effusion was detected by echocardiography. The typical angiographic features of aortic dissection were not found. Autopsy revealed a longitudinal intimal tear and a rupture in the postero-lateral aspect of the ascending aorta. No false lumen was seen in the ascending aorta. When acute intrapericardial or intrapleural bleeding develops with no evidence of aortic aneurysm or dissection, spontaneous aortic rupture should be suspected.

Aged

Primary anastomosis for acute ascending aortic dissection.

Intimal tear resection and primary anastomosis of the aorta were used for the treatment of eight patients with DeBakey I and II type acute aortic dissection. Five patients were of DeBakey I type, and three patients were of the II type. Moderate or severe aortic regurgitation (AR) was observed in six of eight patients. The site of the intimal tear was diagnosed by intraoperative echocardiography, and the adventitia corresponding to the intimal tear was transversely opened under total cardiopulmonary bypass. While resuspension of the aortic valve was performed on only one of six patients, AR disappeared in four, postoperatively. Two of eight patients died early postoperatively. The cause of death was postoperative cardiac tamponade in one patient and cerebral herniation in the remaining one. The other six patients have been observed for a mean period of 27 months. There is no late death, and they show no dilatation of the aortic root and deterioration of AR. We believe that this operative method is a simple and safe emergency procedure for DeBakey I and II type acute aortic dissection.

Acute Disease

Beta-blocking potency and selectivity of bopindolol and its two metabolites for beta 1- and beta 2-adrenergic receptors as assessed by radioligand binding assay.

Using a radioligand binding assay, we assessed the affinity and selectivity of the antagonistic effects of bopindolol (4-(benzoyloxy-3-tert-butylaminopropyl)-2-methylindole hydrogen-malonate) and its two metabolites, (18-502, (4-(3-tert-butylamino-2-hydroxypropoxy)-2-methyl indole) and 20-785, (4-(3-tert-butylaminopropoxy)-2-carboxyl indole], for beta 1- and beta 2-adrenoceptors and on 5HT1B-receptors in rat brain and heart. In addition, we also determined the pA2 values of these agents for their antagonistic effects toward positive chronotropic and inotropic actions (beta 1-adrenoceptors) and for their antagonistic effects toward isolated tracheal relaxation (beta 2-adrenoceptors), using isoproterenol as an agonist. The data showed that bopindolol was more selective for beta 2-adrenoceptors than for beta 1-adrenoceptors and 5HT1B-receptors, but its two metabolites (18-502 and 20-785) did not have significant selectivity for beta 1- and beta 2-adrenoceptors, using both [3H]CGP12177 and [125I]ICYP ([125I]iodocyanopindolol) bindings. In contrast, the results from pharmacological assessment for antagonistic potencies, using atria and trachea, showed that bopindolol and its two metabolites did not have significant selectivity on beta 1- and beta 2-adrenoceptors. A major metabolite of bopindolol, 18-502, had higher pKi and pA2 values for beta-adrenoceptors and 5HT1B-receptors than those of bopindolol and 20-785. These results indicate, first, that a radioligand binding assay for the assessment of the selectivity of bopindolol and its two metabolites for beta 1- and beta 2-adrenoceptors is more effective than pharmacological experiments, and that there is a possibility that its two metabolites also contribute to the strong beta-blocking action of bopindolol.

Adrenergic beta-Antagonists

Structural and functional characterization of calelectrins from bovine liver.

Two Ca2(+)-dependent membrane-binding proteins with apparent molecular weights of 70000 (calelectrin70) and 32000 (calelectrin32) were isolated from bovine liver using phenyl-Sepharose affinity chromatography followed by diethylaminoethyl (DEAE)-cellulose and Ultrogel AcA44 chromatographies. Limited proteolysis and immunological analyses indicated that calelectrin32 was not a digested product from calelectrin70. Both calelectrins bound to phosphatidylserine and to calmodulin in a Ca2(+)-dependent manner. Circular dichroism studies showed that the apparent alpha-helical contents of calelectrin70 and calelectrin32 were 25 and 40%, respectively and they underwent Ca2(+)-dependent conformational changes. When the calelectrins were incubated with a brain microtubule preparation, they were phosphorylated by endogenous kinase(s) and phosphorylation occurred on serine residues. Moreover, calelectrin70 showed an inhibitory action on endogenous kinase activity in the presence of Ca2+.

Animals

Avirulent ts and thymidine kinase-deficient mutant of Aujeszky's disease virus.

The temperature-sensitive (ts), thymidine kinase-deficient (TK-) mutant designated ZHtsTK- strain, of Aujeszky's disease virus (ADV) was isolated from a virulent strain with the treatments using 5-bromodeoxyuridine and arabinosylthymine. The ZHtsTK- strain was easily distinguished from the other virulent ADV strains by plaque size on HmLu-1 and chicken embryo fibroblast cells and by restriction endonuclease analyses using Bam HI, Sal I and Kpn I. The ZHtsTK- strain was avirulent for mice, guinea pigs and rabbits, and produced neutralizing antibodies to ADV in these animals. The rabbits inoculated with the ZHtsTK- strain did not shed detectable amounts of virus after dexamethasone treatment. The ZHtsTK- strain was also avirulent for 5-day-old piglets and did not cause disease. No virus was detected from the piglets inoculated intramuscularly in the nasal swabs or the tissues examined on postinoculation day 9. These findings presented here suggested that there is a significant correlation between pathogenicity and properties such as ts and TK-, and the combination of ts and TK- properties plays a much larger role in reducing virulence for animals.

Animals

[Surgical treatment of acute ascending dissection--a simplified operative method].

Primary anastomosis for acute ascending aortic dissection was performed in 8 patients. Primary anastomosis included resection of the intimal tear where applicable, a circumferential suture line in the ascending aorta at the site of the tear, and wrapping of the anastomosis of the ascending aorta with Dacron vascular prosthesis. The aortic valve was resuspended in 1 of 6 patients associated with aortic regurgitation. In 4 patients, aortic regurgitation disappeared postoperatively. Two patients show minor non-progressive valve regurgitation. Two of 8 patients died early postoperatively. There was no late death and dilatation of the aortic root in the follow-up period of mean 27 months. On the basis of these results, we believe that primary anastomosis is a simpler and safer operative method for acute dissection of the ascending aorta.

Acute Disease

[Surgical treatment of the aortic arch dissection--a report of two cases operated by partial brachiocephalic perfusion, and open aortic anastomosis].

Two patients underwent aortic arch replacement for the dissecting aneurysm of the aorta using a simplified cardiopulmonary bypass (CPB) technique with partial brachiocephalic perfusion, moderate systemic cooling (22 degrees to 23 degrees C), and open aortic anastomosis were reported. The partial brachiocephalic perfusion was accomplished by perfusion to the right axillary artery using separate pump. Open distal anastomosis was performed under low flow hypothermic perfusion of the lower body during selective perfusion to the brain. Cardiopulmonary bypass and partial brachiocephalic perfusion time were 170 minutes, and 30 minutes in one case, and 207 minutes, 56 minutes in the other case. Both patients survived operations, and there were no postoperative strokes, and neurological complications. On the basis of these results, we discussed about supportive methods for aortic arch surgery.

Anastomosis, Surgical

[Combined operation for renovascular hypertension and ischemic heart disease].

We have experienced two patients of ischemic heart disease associated with renovascular hypertension. Patient 1 (60-year-old man) underwent LV aneurysmectomy and triple aortocoronary bypass grafting (saphenous vein to diagonal branch, left internal mammary artery to obtuse marginal branch, and right gastroepiploic artery to right coronary artery). Seventy five days after the initial cardiac surgery endarterectomy for the left renal artery and bifurcated Dacron graft implantation for the iliac artery obstruction were performed. Patient 2 (62-year-old woman) underwent simultaneous operation of both right nephrectomy and triple aortocoronary bypass grafting (saphenous vein grafts to obtuse marginal branch and right coronary artery, and left internal mammary artery to left anterior descending artery). Their postoperative courses were uneventful except unstable and high blood pressure for four to seven days after the operation. It appears that it should be decided to achieve either simultaneous or two stage approach for ischemic heart disease associated with renovascular hypertension based on the preoperative cardiac function. And both postoperative cardiac function and hypertension should be carefully managed until the blood pressure becomes stable after the surgery.

Coronary Artery Bypass

[Surgical treatment of massive pulmonary embolism--the time of the operation and its effectiveness].

The records of 6 patients undergoing pulmonary embolectomy for massive pulmonary embolism (MPE) at Kurume University Hospital during 17 years were reviewed to determine the management of surgery. The patients consisted of 2 men and 4 women. The patients' ages ranged from 29 to 68 years (mean age, 49.3 years). The records showed that one patient died of brain death after operation and the others survived. All the patients complained of chest pain, anterior chest discomfort and dyspnea. Sudden syncope was observed in 2 patients. Artificial mechanical ventilation was performed preoperatively on 3 patients. Right ventricular load was demonstrated on electrocardiograms and ultrasonograms. Pulmonary angiograms were attempted on two patients and one of them had cardiac arrest during this examination. MPE was suspected by perfusion defect of 50% to 80% of pulmonary vasculature demonstrated on lung perfusion scintigram in 4 patients. Open pulmonary embolectomy with cardiopulmonary bypass (CPB) was performed on all patients using crystalloid cardioplegia and topical cooling. Intraoperative pulmonary angiograms were performed in 4 patients to prevent residual thromboemboli. Since most thromboemboli originate below the level of the vena cava, acute double ligation of the vena cava just below the renal vein was performed to control recurrent embolism. Oral anticoagulant, warfarin, was administered for 3 months after embolectomy as prophylaxis against postoperative recurrent embolism. It is our opinion that an aggressive attitude toward pulmonary embolectomy on CPB is necessary to save lives of MPE patients. This surgical procedure is very easy and safe.

Adult

Isolation and preliminary characterization of an orbivirus of the Palyam serogroup from biting midge Culicoides oxystoma in Japan.

An orbivirus of the Palyam serogroup was isolated from Culicoides oxystoma collected in a cowshed in Kagoshima, Southern Kyushu Island, Japan. This is the first isolation of an orbivirus of the Palyam serogroup in Japan. The virus was a spherical non-enveloped RNA virus, approximately 60 nm in diameter. The virus was resistant to ethyl ether, sodium deoxycholate and freezing-thawing, but readily inactivated by trypsin. The virus was not stabilized by 1 M MgCl2, was labile at pH 3.0 and was not precipitated by protamine sulfate. Indirect immunofluorescent staining of infected Vero cells indicated the virus to be antigenically related to D'Aguilar and Bunyip Creek viruses of the Palyam serogroup. Neutralization tests showed the virus to have no relationship with D'Aguilar virus, but to have a one-way cross-reaction with Bunyip Creek virus. The virus was tentatively designated as Kagoshima virus. A serological survey indicated dissemination of the virus in cattle populations in Kagoshima Prefecture.

Animals

[An autopsied case of an aged patient with advanced gastric cancer that showed a complete response to immunochemotherapy].

Described is the case of an 88-year-old male suffering from advanced hemorrhagic gastric cancer who, because of surgical risk factors, was conservatively treated with immuno-chemotherapy in the form of suppositories containing ftorafur (FT-207) and Picibanil (OK-432). The patient showed marked clinical improvement from this therapy. However, his advanced age and other associated complications kept us from performing further examinations, such as an upper-G-I series and a gastrofiberscopy. A year and 4-months later, the patients died of pneumonia and subsequently was autopsied. Macroscopically, his gastric tumor was found to have completely disappeared and had been replaced by a yellowish-white scar tissue. Microscopically, no cancer cells were found in the examined specimens or in the regional lymph nodes.

Adenocarcinoma