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Biomedical subjects

A Hashimoto

Publications and source records attributed to A Hashimoto.

At least 235 records · Page 13Linked to original sources

[Evaluation of (1-3)-beta-D-glucan in aspergillosis and cryptococcosis].

(1-3)-beta-D-Glucan (beta-glucan) is a major structural component of fungi. The G test is a direct method to detect beta-glucan using fractionated (1-3)-beta-D-glucan-sensitive component, factor G, eluted from the limulus lysate. Previously, we reported that the G test is a more sensitive method than the mannan detection assay for the serological diagnosis of Candida infection. In this study, we discuss beta-glucanemia in patients with pulmonary aspergillosis and cryptococcosis. The concentration of beta-glucan was less than 10 pg/ml in 9 of 10 cases of pulmonary cryptococcosis, except for one case receiving hemodialysis (16.5 pg/ml). beta-Glucan increased in 3 cases of invasive pulmonary aspergillosis (27-937 pg/ml). Galactomannan antigen was positive in all of those cases. In 8 cases of aspergilloma, which showed fungus ball on roentgenogram, the mean concentration of beta-glucan was 67.1 +/- 92.7 pg/ml. Two of 8 cases were positive for galactomannan antigen. One of three cases of PAIC (productive aspergilloma on the inner wall of a cavity) and one case of chronic necrotizing pulmonary aspergillosis showed slightly increased levels of beta-glucan and positive results of galactomannan antigen test.

Adult↗

[Directions for reoperation of patients with Björk-Shiley convexo-concave valve prosthesis, based on long-term experience].

Although a high incidence of strut fracture of the Björk-Shiley convexo-concave (C-C) valve prosthesis has been reported, it is still controversial whether the prosthesis functioning normally should be replaced electively. To clarify our policy for this issue, we reviewed 28 patients who had undergone mitral valve replacement with a C-C valve prosthesis, and evaluated long-term results according to STS guidelines. The incidence of valve-related complications expressed as % patient-year were; structural deterioration 0.30, nonstructural dysfunction 0.30, thromboembolism 1.20. There were no thrombosed valves, anticoagulant-related hemorrhage or prosthetic valve endocarditis. The actuarial free rate after valve replacement with the C-C at 10 years, constructed by the Kaplan-Meier method, were compared with those with St. Jude Medical (SJM) valve prosthesis. (1) Actuarial survival: 77.9 vs 87.3 (NS), (2) Reoperation-free: 91.6 vs 98.0 (p < 0.05), (3) thromboembolism-free: 83.7 vs 83.9 (NS), (4) Event-free (hospital death+reoperation+valve-related complications: 71.2 vs 77.7 (NS). The long-term results with the C-C were compatible to those with a SJM valve prosthesis. However, if a strut fracture occurs, it is very difficult to save the patient's life. The hospital mortality of re-replacement of valve prosthesis during the last 10 years, at our institute, was 2.6%, which is almost equal to the cumulative risk of strut fracture of the C-C valve after 10 years (3.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Exercise-induced STV1 elevation: a sign of right ventricular dysfunction in recent inferior myocardial infarction.

BACKGROUND: Little is known about exercise-induced electrocardiographic ST segment shift in right-sided precordial leads, especially elevated ST in patients with subacute inferior myocardial infarction. OBJECTIVE: To test the clinical significance of exercise-induced STV1 deviation with special regard to right ventricular function and right ventricular involvement. DESIGN: Sixty-eight patients with recent inferior myocardial infarction (without having a left descending arterial lesion) aged 30 to 73 years (mean +/- SD, 59.1 +/- 10.0) were investigated with respect to biventricular function observed in radionuclide ventriculography and treadmill stress electrocardiographic findings. RESULT: STV1 shift during exercise (delta STV1) had a negative linear logarithmic relationship only with the right ventricular ejection fraction (RVEF) and no correlation with the left ventricular ejection fraction (delta STV1 = 6.7604-1.7528xlnRVEF, r = 0.709, P = 0.0001). Significant STV1 elevation (delta STV1 of 0.5 mm or more) predicted right ventricular dysfunction (RVEF of 40% or less) and right ventricular infarction with sensitivities of 76% and 77%, specificities of 88% and 92%, and accuracies of 84% and 77%, respectively. Twenty patients with STV1 elevation (0.5 mm or more) showed nearly identical rest and exercise electrocardiographic findings, exercise capacities and similar stenotic lesions on coronary angiography, to 43 patients without significant STV1 elevation. Elective balloon angioplasty reduced the delta STV1 during exercise in only three of six patients (50%) with right ventricular infarction. CONCLUSION: Exercise-induced STV1 elevation may be a useful indicator of global right ventricular dysfunction and/or right ventricular infarction in the subacute phase of myocardial inferior infarction.

Adult↗

[Reoperations on valvular disease: an analysis of outcome].

To evaluate risks and complications of reoperation on valvular disease, we reviewed data on 186 patients who underwent reoperations because of prosthetic valve malfunctions, pregression of valvular disease after open mitral commissulotomy and previous valvular replacement. Overall hospital mortality was 4.8% (9/186 patients). The common causes of death was low cardiac output syndrome (3 pts.) and respiratory failure (3 pts.) and others (3 pts). Hospital mortality was different according to the risk factors. There was no significant difference between the operative procedures; AVR (6.2%), MVR (3.2%), DVR (8%), TVR (0%) and MVR + TVR (9%). Furthermore, advanced age, valve position, renal failure, preoperative %FS, LVDd and diagnosis of prosthetic valve malfunction did not appear to be significant risk factor. However, preoperative respiratory failure and emergency operation showed significant increase of hospital mortality in comparison with other factors. On the basis of this reports, hospital mortality and late survival indicated that reoperation should be performed early as the potentially safe condition.

Disease Progression↗

[Surgical treatment of false aneurysms following Bentall's operation].

Between January 1973 and June 1993, 157 patients had Bentall's operation and its modifications for the surgical treatment of annuloaortic ectasia and dissecting aneurysm in our institute. Reoperation for false aneurysms following Bentall technique were performed 10 patients. There were 8 males and 2 females. This ages ranged from 29 to 57 years with an average of 41. The interval between initial and subsequent operation was from 3.7 to 18.4 years (median, 8.2 years). Prior to a median sternotomy, femoro vein-femoral artery partial cardiopulmonary bypass was instituted occationaly. Operative technique of repair of coronary detachment were direct closure in 6 and interposition graft technique in 4 patients. There were 2 hospital death caused by rupture at median aternotomy and graft infection. The actuarial freedom from reoperation at 10 years according to technique of coronary reattachment, for the patients with one lane suture was 69%, for those with two lane suture was 95% (p < 0.01), and for those with interposition graft technique was 100%. In conclusions, it was very important for repair of false aneurysms following Bentall procedure to expose aneurysms safely through proper approach. Interposition graft technique was preferable to repair coronary detachment. Our recent surgical results of Bentall procedure improved by the modification of the coronary reimplantation method.

Adult↗

Widespread distribution of free D-aspartate in rat periphery.

We have identified and quantified free D-aspartate in adult rat peripheral organs using gas chromatographic-mass spectrometric and high-performance liquid chromatographic techniques. The level of free D-aspartate was highest in the adrenal, testis, spleen and pituitary, followed by the thymus, lung, ovary, placenta, pancreas and heart, and below the detection limit in the kidney, liver, brain, muscle and serum. These data provide the first evidence that a high level of free D-aspartate widely occurs in the adult rat periphery and suggest that the D-amino acid may be an endogenous substrate for D-aspartate oxidase.

Animals↗

Free D-serine, D-aspartate and D-alanine in central nervous system and serum in mutant mice lacking D-amino acid oxidase.

We have examined whether D-amino acid oxidase (DAO) regulates free D-serine content using mutant ddY/DAO- mice lacking DAO activity. We find that the content of D-serine in the serum and cerebellum of mutant mice is much higher than that of normal mice, whereas a slight but significant difference in the cerebral D-serine level is observed between the two strains. These results suggest that, although DAO may participate in the catabolism of D-serine in the cerebellum and periphery, there appears to be other mechanisms for catabolism of endogenous D-serine in the brain.

Alanine↗

Studies on percutaneous transvenous mitral commissurotomy using a modified transseptal approach.

A modified version of Brockenbrough's trans-septal catheterization technique was carried out in 11 patients indicated for percutaneous transvenous mitral commissurotomy (PTMC). In 8/11 (72.7%), a coiled guide-wire was successfully inserted through the foramen ovale without atrial septal puncture. The Brockenbrough needle was used merely to maintain stiffness and the orientation of the dilator. PTMC was performed with an Inoue single balloon without incident. Patent foramen ovale was found by transesophageal echocardiography prior to the operation in only 1/11 patients (9.0%); nonetheless, it proved not to be a critical factor for the success of the procedure. This procedure seems to have much potential to enable the treatment of mitral stenosis with a lowered risk to the patient, as long as it is performed with precision and caution.

Adult↗

Synthesis and evaluation of 1-(1-[5-(2'-[18F]fluoroethyl)-2-thienyl]-cyclohexyl)piperidine as a potential in vivo radioligand for the NMDA receptor-channel complex.

1-(1-[5-(2'-[18F]Fluoroethyl)-2-thienyl]cyclohexyl)piperidine (18FE-TCP) was prepared as a fluorine-substituted analogue of the potent NMDA receptor channel blocker, 1-[1-(2-thienyl)cyclohexyl]piperidine (TCP), by the mesylate displacement with [18F]fluoride ion with isolated radiochemical yields of 6-12%, and the synthesis time including a two step HPLC purification was 120 min. The regional distribution in rat brain after i.v. injection of 18FE-TCP was heterogeneous and similar to the known distribution of phencyclidine recognition sites, with hippocampus-cerebellum, striatum-cerebellum and cerebral cortex-cerebellum concentration ratios of 2.08, 1.7 and 1.54, respectively, 15 min post-injection. Furthermore, this localized regional cerebral distribution was blocked by co-injection with the unlabelled FE-TCP or pretreatment with cis-2-hydroxymethyl-r-1-(N-piperidyl)-1-(2-thienyl)cyclohexane, with the greatest reductions seen in the hippocampus followed by the striatum and cerebral cortex. However, relatively low receptor binding affinity and high non-specific binding due to its high lipophilicity suggest that 18FE-TCP may not be a suitable radioligand for in vivo PET investigations of the NMDA receptor-channel complex.

Animals↗

Vaccination with hatched but non-activated, non-viable oncospheres of Taenia taeniaeformis in rats.

The usefulness of hatched but non-activated oncospheres as a candidate vaccine was evaluated using a Taenia taeniaeformis/rat system, since preparation of these oncospheres in vitro is known to be very simple. The findings were: (1) rats vaccinated with non-viable oncospheres became completely resistant to challenge infection; (2) intra-venous injection was the most effective to induce complete resistance; (3) a single oncosphere was sufficient to induce complete resistance in infected rats, whereas approximately 50 and 500 non-viable oncospheres were required to evoke strong and complete resistance, respectively, in vaccinated rats. The usefulness of non-viable oncospheres without adjuvant is discussed.

Animals↗

Endogenous D-serine in rat brain: N-methyl-D-aspartate receptor-related distribution and aging.

Recently, a substantial amount of free D-serine has been demonstrated in rat brain, although it has long been presumed that D-amino acids are uncommon in mammals. The anatomical distribution and age-related changes in endogenous D-serine have been examined here to obtain insight into its physiological functions. Free D-serine exclusively occurs in brains, with a persistent high content from birth to at least 86 postnatal weeks. The patterns of the regional variations and the postnatal changes in brain D-serine are closely correlated with those of the N-methyl-D-aspartate (NMDA)-type excitatory amino acid receptor. Because D-serine potentiates NMDA receptor-mediated transmission by selective stimulation of the strychnine-insensitive glycine site of the NMDA receptor, it is proposed that D-serine is a novel candidate as an intrinsic ligand for the glycine site in mammalian brain.

Aging↗

Embryonic development and postnatal changes in free D-aspartate and D-serine in the human prefrontal cortex.

We have analyzed free chiral amino acids (aspartate and serine) in the human frontal cortex at different ontogenic stages (from 14 weeks of gestation to 101 years of age) by HPLC with fluorometric detection after derivatization with N-tert-butyl-oxycarbonyl-L-cysteine and o-phthaldialdehyde. Exceptionally high levels of free D-aspartate and D-serine were demonstrated in the fetal cortex at gestational week 14. The ratios of D-aspartate and of D-serine to the total corresponding amino acids were also high, at 0.63 and 0.27, respectively. The concentration of D-aspartate dramatically decreased to a trace level by gestational week 41 and then remained very low during all postnatal stages. In contrast, the frontal tip contained persistently high levels of D-serine throughout embryonic and postnatal life, whereas the D-amino acid content in adolescents and aged individuals was about half of that in the fetuses. Because D-aspartate and D-serine are known to have selective actions at the NMDA-type excitatory amino acid receptor, the present data suggest that these D-amino acids might play a pivotal role in cerebral development and functions that are related to the NMDA receptor.

Adolescent↗

Mechanical circulatory support for postcardiotomy ventricular failure: the Heart Institute of Japan experience 1984-1992.

In the last 9 years, 30 patients received assisted circulation or a ventricular assist device after open-heart operations at the Heart Institute of Japan. After cardiovascular surgery, 9 of those patients underwent venoarterial bypass, 10 had biventricular bypass, 7 had left ventricular bypass, and the remaining 4 received a left ventricular assist device. Of the first 15 patients, only 3 (20%) were discharged from the hospital. In contrast, 7 (46.7%) of the last 15 patients were discharged without major complications. With respect to complications, bleeding and ventricular arrhythmia (immature weaning) decreased with low-heparinized isolated left ventricular supports. However, profound biventricular failure, infection, and multiple organ failure remain as possible complications with any type of assisted circulation. These results suggest that early application of circulatory support and appropriate selection of the mode of support and devices used are important for successful circulatory support.

Adult↗

Percutaneous cardiopulmonary support as the second generation of venoarterial bypass: current status and future direction.

We have developed a new percutaneous cardiopulmonary support (PCPS) system in cooperation with Terumo Corporation, called the Emergency Bypass System (EBS). This preassembled system is unique in terms of its small priming volume (470 cc), fully automatic priming function, originally developed membrane oxygenator, and Capiox straight path centrifugal pump. The priming process takes only 5 min. We have used this system in 4 patients (all were male; mean age 56 years, range 35-73 years). The duration of assist ranged from 15 min to 210 h. Maximum bypass flow ranged from 2.2 to 3.6 L/min, systemic circulation was very well maintained, and urinary output was acceptable. Although the centrifugal pump was in good working condition, we had to change the oxygenator because of serum leakage 36 to 48 h after initiation of the assist. One patient was weaned from the PCPS, but died of brain death. The other patients could not be weaned from the PCPS. The cause of death in these patients was irreversible myocardial damage. Disseminated intravascular coagulopathy triggered by surgical trauma related to various procedures developed in 2 patients during assist and was the cause of cessation of the assist. Problems to be ratified and future directions in the EBS and PCPS were earlier introduction through the establishment of clear indications and endpoint, heparin coating, improvement in durability of the oxygenator, and cost.

Adult↗

Clinical experience of assisted circulation with a centrifugal pump at Tokyo Women's Medical College.

In postpericardiotomy patients, the use of pulsatile pumps is limited in a semielective fashion to patients whose postoperative marginal hemodynamics are expected preoperatively. Since 1989, 25 patients have undergone assisted circulation with a centrifugal pump: 15 (60%) were weaned from the pump, and 7 (28%) survived. In 1988, we heparin-coated the Bio-Pump using the Carmeda technique and developed a totally heparin-coated left heart bypass system together with heparin-coated cannulas and tubing. Four postpericardiotomy patients underwent left heart bypass with this system without heparin for 2 to 9 days. No thrombus was detected in the system. Left heart bypass with a centrifugal pump has been used as a supportive method in surgical repair of thoracic or thoracoabdominal aortic aneurysm. To overcome intraoperative hypothermia and hypoxia, we used a small membrane oxygenator with a heat exchanger in 11 patients, and postoperative recovery dramatically improved. We also developed a preassembled percutaneous cardiopulmonary support (PCPS) system with an automatic priming function using Terumo's straight path centrifugal pump and small membrane oxygenator in cooperation with the Terumo Corporation. This system was used in a patient with cardiogenic shock after acute myocardial infarction. The setup and priming took only 5 min, and 2.5-3.5 L/min of flow was obtained.

Adult↗