[Laryngeal mask for general anesthesia].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to H Okazaki.
Explore the source record for details and available documents.
We studied the influence on cerebral hemodynamics with 10 pigs, weighing 25 to 30 kg, when the temperature of perfusion blood changed in both rapid cooling and rewarming, and in slow them. As for the protocol of temperature, we decided that rapid change was the large temperature gradient of more than 0.5 degree C/min, and slow change was the small gradient of less than 0.3 degree C/min. Cardiopulmonary bypass (CPB) was established with a flow rate of 60 ml/kg/min, and core cooling was performed until the temperature of the returned blood from internal jugular vein reached 25 degrees C/min. For selective cerebral perfusion (SCP), blood was infused into aortic arch with the clamp of descending aorta at the temperature of less than 20 degrees C. We measured regional tissue cerebral blood flow (TCBF), intracranial pressure (ICP), carotid arterial flow (CAF), and carotid arterial pressure (CAP), and PCO2 in both CPB and SCP. Rapid cooling during CPB caused an elevation in CAP, and marked decrease in CAF, ICP, and PCO2. In contrast, rapid rewarming caused the significant increase in CAF, ICP. Slow change did not cause marked difference in CAP, CAF, and ICP, and PCO2. Moreover, TCBF was not significant in both rapid and slow changes. On the other hand, rapid change in SCP caused a significant decrease in CAP, significant difference in CAF, ICP. Slow change did not cause significant difference in them as same as in CPB. In conclusion, we presume that the influence on cerebral hemodynamics is less in slow cooling and rewarming than in rapid changes.
A 62-year-old man who had undergone left lingual segmentectomy for pulmonary tuberculosis developed left chronic localized pleural empyema with multiple bronchial fistulae in the region of surgical gauze left in the thoracic cavity. We surgically removed the gauze and fenestrated the empyema. After disinfection of the region of suppuration, small fistulae which were less than 2 mm in diameter were closed by fibrin-glue-packing and consolidation of the orifices using 40% silver nitrate solution. Two and one-half months later a second operation was performed. Residual large fistulae were closed by fibrin-glue-packing and suturing of their orifices, and the empyema space was then obliterated by muscle flap plombage. The patient's postoperative course was good and the empyema was completely cured with this treatment.
Comparison of long term clinical results after aortic valve replacement with 19 mm or 21 mm vs. 23 mm or larger bileaflet prostheses has not yet been reported. Between December 1979 and September 1993, 80 consecutive patients who underwent isolated aortic valve replacement at Niigata University using a standard St. Jude Medical valve were assigned to small size group (19 mm and 21 mm, n = 34) or to large size group (23 mm or larger, n = 46). In the small size group, patient's age was older, body surface area smaller, female patients and calcified aortic stenosis were dominant (all p < 0.01). The left ventricular systolic dimension was shorter (p < 0.001), while the cardiothoracic ratio was similar to that of the large size group. All patients received warfarin treatment, and target thrombotest level was 15 to 25% (equivalent to INR 1.6 to 2.1). Actuarial survival rates including hospital death in the small size group (94% at fifth postoperative year) were comparable to those in the large size group. Cerebrovascular event occurred in two patients with the small size prosthesis (1.3%/pty) and three with larger prosthesis (0.9%/pty). Major hemorrhagic complication was not observed in either group. No significant difference was noticed in the proportion free from valve-related morbidity. In the patients with aortic stenosis (n = 41), the left ventricular posterior wall thickness decreased from 15 mm preoperatively to 11 mm late post surgery in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)
The purpose of this study is to evaluate the long-term renal function of donors after nephrectomy in living related renal transplantation (n = 100). The survival rate of donors was 98% and causes of death in the other 2% were not associated with the donation. Serum creatinine (Scr) and Creatinine clearance (Ccr) deteriorated just after the donation, but gradually improved. The number of donors with proteinuria increased after donation. In Scr and Ccr there was no significant difference between donors with and without proteinuria. In the donors with hypertension (25.3%) mean urine protein was higher than in those without hypertension. There was a correlation between systolic blood pressure and proteinuria. These results strongly suggest that renal function of donors deteriorates once just after the donation, but gradually improves year by year, and that hypertension is strongly associated with renal dysfunction, especially proteinuria, after the donation.
This study was undertaken to clarify characterization on cerebral hemodynamics during deep hypothermic selective perfusion (SCP) in 18 pigs. Besides, the changes on cerebral hemodynamics were investigated with obstruction to venous drainage due to the clamp of superior vena cava (SVC) cannula. For SCP, blood was infused into aortic arch with the clamp of descending aorta, during 90 minutes at 20 degrees C. We measured regional cerebral blood flow (CBF), intracranial pressure (ICP), and carotid arterial flow (CAF), and carotid arterial pressure. The carotid arterial pressure as perfusion pressure was not significantly correlated with CAF, CBF and ICP. Although CAF increased as pump flow rate increased, the relationship between pump flow and CBF was not significant. Moreover, SVC pressure showed a tendency to increase, as CAF increased. Both ICP and internal jugular vein pressure (IJVP) were significantly (p < 0.01) increase, and CAF was significantly (p < 0.05) decrease with the clamp of SVC cannula. On the other hand, both ICP and IJVP were significantly decrease, and both CAF and CBF were increase, without unclamp of SVC cannula. The results suggest that cerebral autoregulation is intact during deep hypothermic SCP, and hyperperfusion cause the increase of shunt flow in extracranial area, and besides, the increase of ICP with obstruction to venous drainage cause decrease in cerebral blood flow.
Explore the source record for details and available documents.
Two cases were operated on simultaneously for coronary revascularization and lung resections for cancer. Case 1 was a 79 year-old man, diagnosed with two vessels coronary artery disease and squamous cell carcinoma of left lower lobe. At the end of aortocoronary bypass grafting to LAD and first diagonal branch using saphenous vein, median sternotomy was closed, and lower lobectomy was performed through left posterolateral standard thoracotomy. Case 2 was a 65 year-old man who underwent aortocoronary bypass grafting to LAD first and left lingular segmentectomy via median sternotomy simultaneously. We concluded that a simultaneous operation was definitively and ideally a preferable method in most selected cases. The order of two operations for coronary artery and lung was also discussed.
Explore the source record for details and available documents.
Angiotensin II plays an important role in neointimal formation after vascular injury. Our objectives were 1) to investigate the difference between angiotensin converting enzyme inhibitors (captopril, delapril) and an angiotensin II subtype 1 (AT1) receptor antagonist (DuP753) in suppressing neointimal proliferation; and 2) to investigate the antiproliferative effects of these drugs given topically to the injured vessels. All these treatments effectively prevented neointimal formation (p < 0.01). Even a single topical application of either type of drug with F127 pluronic gel to be injured vessel after ballooning is found to be significantly effective probably due to the inhibition of smooth muscle cell migration (p < 0.01). Multiple systemic application of angiotensin converting enzyme inhibitors was more effective than that of DuP753 at the same blood pressure level. The effectiveness of topical application of these drugs suggests clinical usefulness after angioplasty or vascular surgery.
Two types of cDNA encoding PACAP receptors were isolated from the rat brain cDNA library by homology screening with a cDNA probe for VIP receptor. Nucleotide sequence analysis indicated that these two types of receptor mRNA were generated by alternative splicing mechanisms. These two cloned cDNAs were introduced into CHO cells respectively. Resultant transformants showed specific binding to [125I]PACAP27 which was displaced by unlabeled PACAP27 but not by VIP. Thus, these receptors are two subtypes of Type I PACAP receptor (Type I-A and Type I-B). The amino acid sequences of rat PACAP receptors deduced by the cDNAs showed a remarkable similarity with rat receptors for VIP, secretin, glucagon, and GHRH. A 6.5 kb significant hybridizing signal of the PACAP receptor mRNA was detected in the rat brain, and slight signal was also detected in the lung and the liver.
A novel cDNA clone encoding a putative G protein-coupled receptor has been isolated from a rat aortic smooth muscle cDNA library. Sequence analysis of this clone reveals the structural features characteristic of this superfamily, with a high degree of sequence similarity to the Edg-1 receptor previously reported to be expressed in vascular endothelial cells. This novel receptor mRNA is expressed predominantly in the lung and heart. Although the ligand for this receptor has yet to be identified, the results suggest the existence of a new receptor subfamily in the cardiovascular system thus far unrecognized.
Articulatory and language impairment heralded rapidly progressive motor neuron disease in 7 patients aged 54 to 77 years. One patient had a family history of a similar disorder. Severe nonfluent aphasia developed in all 7 patients and 4 were anarthric within a year. Other cognitive domains were impaired, yet 2 patients lived alone until 1 month before their deaths. Four died within 2 years. Abnormalities were found on electromyography, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, and electroencephalography. Neuropathological examination in 3 patients showed bilateral hemispheric atrophy with neuronal loss and gliosis predominantly of superficial cortical layers. Pigmented and hypoglossal nuclei were relatively preserved. At all spinal levels there was degeneration of corticospinal tracts and loss of anterior horn cells with gliosis. Rapidly progressive aphasic dementia and motor neuron disease are a distinctive clinical entity whose nosology is poorly understood.
This report concerns the expression of ubiquitin in anterior horn cells of various subgroups of adult and infantile motor neuron disease (MNDs); immunohistochemical techniques were employed. Ubiquitin-positive skein-like inclusions (SLIs) were found in all cases of adult-onset amyotrophic lateral sclerosis (ALS), including 16 cases with sporadic ALS, two cases of familial ALS with posterior column degeneration and Lewy body-like hyaline inclusions (LBHIs), two sporadic ALS cases with LBHIs, and three cases of sporadic ALS with dementia. SLIs were not found in anterior horn cells of 5 cases with Werdnig-Hoffmann disease (WHD). However, granular ubiquitin-positive deposits were seen in ballooned neurons of WHD patients. No ubiquitinated materials were found in the perikarya of two sporadic juvenile ALS patients with basophilic inclusions (BIs), but granular ubiquitin-immunoreactive deposits were occasionally observed in the BIs. These results suggest that ubiquitin-positive SLIs are characteristic features of various forms of adult-onset ALS and that aggregated ubiquitinated granules are characteristic of ballooned neurons of WHD. Ubiquitinated structures and their distribution patterns may reflect degenerative processes of anterior horn cells, and may be useful for classifying subgroups of motor neuron diseases.
Nitric oxide (NO)-generating vasodilators inhibit the mitogenesis and proliferation of cultured vascular smooth muscle cells. We investigated the role of NO in the vascular response to arterial injury by administering L-arginine (precursor of NO), D-arginine or N-nitro L-arginine methylester (NAME; an inhibitor of NO synthesis) to a rat model of balloon catheter-induced left carotid artery injury. Two weeks after the balloon injury, animals that received both oral (1.25 g/l water) and local (10mg in gel) administration of L-arginine showed suppression of neointimal proliferation with no change in systolic blood pressure. Medial proliferation was potentiated in NAME-treated animals with a higher blood pressure. Tissue cGMP content (representative of NO generation) of the injured arteries was similar to that of normal arteries with intact endothelium. These findings suggest that a higher local concentration of NO produced from L-arginine can inhibit the migration and proliferation of smooth muscle cells in the injured vascular wall.
There is evidence that glucose sensors and arginine sensors are present in the hepato-portal system and exert a reflex regulation of the pancreatic neuroendocrine system in normal rats. To investigate the function of these sensor systems in liver cirrhosis, we examined the effect of hepatic vagotomy on plasma glucose and insulin concentrations after intraperitoneal (IP) injection of glucose or L-arginine in carbon tetrachloride (CCl4)-induced cirrhotic rats. After IP glucose injection, hepatic vagotomy decreased plasma insulin with elevation of plasma glucose in control rats; however, in cirrhotic rats, this procedure did not affect either plasma glucose or insulin concentrations. After IP arginine injection, hepatic vagotomy increased plasma insulin and reduced plasma glucose in control rats, although in cirrhotic rats, this procedure did not affect plasma glucose but did increase plasma insulin concentrations. These results suggest that function of the glucose sensor in CCl4-induced cirrhotic rats is disturbed, although that of the arginine sensor is retained.
Hepatocyte growth factor (HGF) has mitogenic and unique morphoregulatory functions, and is considered to act as a hepatotrophic and a renotrophic factor for regeneration of the liver and kidney subjected to various insults. We have now obtained evidence that heparin is a potent inducer of HGF production. The addition of heparin to a culture of MRC-5 human embryonic lung fibroblasts increased the HGF concentration in the conditioned medium, in a dose-dependent manner. The maximal stimulation was obtained at 1 microgram/ml heparin and stimulation was 4-fold compared to control cultures. The rate of HGF synthesis in MRC-5 cells, as measured by pulse-labeling with [35S]methionine, and subsequent immunoprecipitation of HGF from both conditioned medium and a cell lysate, was 3-4-fold stimulated by 1 microgram/ml heparin, whereas heparin apparently had no significant effect on the HGF mRNA level. The stimulatory effect of heparin on HGF production was evident in various types of cells, such as MRC-9, IMR-90, and WI-38 human embryonic lung fibroblasts, human skin fibroblasts, HL-60 human promyelocytic leukemic cells and human umbilical vein endothelial cells. In addition to heparin, heparan sulfate also stimulated HGF production, albeit to a lesser extent than heparin; 1.7-fold stimulation with 2 micrograms/ml heparan sulfate. However, other glycosaminoglycans, such as hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, and keratan polysulfate, had no stimulatory effect on HGF production.(ABSTRACT TRUNCATED AT 250 WORDS)
OBJECTIVE: The aim of this study was to determine the efficacy of color Doppler sonography in the diagnosis of portal vein thrombosis in patients with primary hepatocellular carcinoma. The findings on angiography were used as the gold standard for diagnosis. SUBJECTS AND METHODS: We compared the findings on color Doppler sonograms and hepatic angiograms in 18 patients with hepatocellular carcinoma and portal vein thrombosis and in 22 patients with hepatocellular carcinoma without portal vein thrombosis. In most patients, tumor-related thrombus of the portal vein was confirmed by autopsy or surgery. The sonographic criteria for diagnosing portal vein thrombosis included nonvisualization of portal vein flow, pulsatile flow in the thrombus, arterioportal shunts, and cavernous transformation of the portal vein. RESULTS: Nonvisualization of portal vein flow was the predominant color Doppler finding in all patients with portal vein thrombosis. Other flow abnormalities overlapped the finding of nonvisualization of portal vein flow in 10 of 18 patients with portal vein thrombosis. The sensitivity of color Doppler sonography was 100% for nonvisualization of portal vein flow, 89% for detection of pulsatile flow in the thrombus, 60% for detection of arterioportal shunts, and 100% for detection of cavernous transformation. Among these findings, pulsatile flow in the thrombus was diagnostic for pathologically proved neoplastic thrombi in the main portal vein; sensitivity and specificity were 89% and 100%, respectively, and accuracy was 96%. No portal vein that appeared normal on color Doppler sonograms was thrombosed on arteriograms. CONCLUSION: We conclude that color Doppler sonography is a useful means of imaging the vascular extension of a tumor-based thrombus and an accurate means of screening for portal vein thrombosis.