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Y Morimoto

Publications and source records attributed to Y Morimoto.

At least 91 records · Page 5Linked to original sources
PubMed2001

Short term effect of silicon carbide whisker to the rat lung.

We studied the short-term effect of silicon carbide whisker (SiCW) in vivo by instillation and inhalation to the rat lung. SiCW was instilled low dose (2 mg/0.5 ml saline) or high dose (10 mg/ 0.5 ml) intratracheally into the lungs of 25 rats. SiCW was also inhaled to another 25 rats at the average concentration of 10.4 mg/m3 for 1 month. In instillation study, the lung had focal alveolitis with the destruction of alveolar wall especially at 3 days after the instillation, and the lesion remained as an aggregated foci of SiCW at 6 months. The 'inflammation-score' of the instilled group by point counting method of the specimen correspondingly decreased gradually. In inhalation group, a minimum inflammatory change was observed. Collagen deposition in the aggregated foci of SiCW with accumulated alveolar macrophages and neutrophils was not progressive during the observed period. These findings suggest that SiCW may cause a minor effect to the rat lung in 6 months after exposure.

Administration, Inhalation↗
PubMed2001

Pharmacokinetic and pharmacodynamic evaluations of a potent analgesic, dihydroetorphine, in hairless rat.

To evaluate the pharmacokinetic and pharmacodynamic characteristics of a novel opioid analgesic, dihydroetorphine (DHE), concentrations of DHE and its glucuronide (DG) in plasma and central nervous system (by liquid chromatography-tandem mass spectrometry) and the antinociceptive effect (by tail-immersion test) were measured after intravenous (i.v., 2 microg/kg), intracutaneous (i.c., 2 microg/kg), subcutaneous (s.c., 2 microg/kg), intraperitoneal (i.p., 10 microg/kg), and oral (p.o., 200 microg/kg) administrations in hairless rats. An elimination half-life of plasma DHE concentration was 37.2 min after i.v. injection. Brain DHE concentration reached a maximum within 6 min after i.v. injection, and the concentration ratio in brain to plasma was 5.17. Relative bioavailabilities of DHE to i.v. injection (100%) were 70.8, 79.8, 16.7, and 0.37% after i.c., s.c., i.p., and p.o. administrations, respectively. Area under the plasma concentration-time curve ratios of plasma DG to DHE concentrations after i.v., i.c., s.c., i.p., and p.o. were 1.76, 3.26, 4.74, 14.5, and 290, respectively. Antinociceptive effects appeared rapidly after i.v., i.c., and s.c. administrations but were diminished after i.p. and p.o. administrations, and these effects were closely related to the brain DHE concentrations. DHE was excreted mainly as DG in bile (89.5% of the dose) by 240 min after i.v. injection. Serum protein binding of DHE was 83.4%, which was not influenced by DG. Glucuronidation of DHE was detected in the liver, intestine, and kidney in vitro but was minimal in the skin and brain. In conclusion, DHE was rapidly distributed to the brain in relation to producing the antinociceptive effect, and then it was rapidly metabolized to the pharmacologically inactive DG.

Algorithms↗
PubMed2001

[Do all patients with mandibular hypoplasia present difficulty in endotracheal intubation?].

On 7 patients with Pierre-Robin syndrome (PR), 8 patients with first and second brachial arch syndrome (BA) and 7 patients with Treacher Collins syndrome (TC), we examined retrospectively the number of patients whom anesthesiologists found difficult to perform laryngoscopy and intubation, the number of attempt necessary for proper insertion of the tracheal tube, the number of patients in whom the endotracheal intubation with laryngoscopy was given up and the time necessary for endotracheal intubation. We compared these with those from 22 control patients. Our results suggest that the difficult laryngoscopy and intubation are more frequent in TC. On the other hand, most of PR and BA may not present difficulty in intubation.

Child↗
PubMed2001

Aortic laceration due to prolapse of the bicuspid aortic valve: case report.

Reports of aortic regurgitation due to rupture of the aortic valve commissures are rare. Prompt surgical intervention is necessary, as the condition results in rapid, progressive heart failure and subsequent death. We report the case of a 78-year-old man who presented with aortic laceration and cardiac tamponade that was probably induced by prolapse of the bicuspid aortic valve. We speculate that prompt initial surgery may have prevented aortic laceration and cardiac tamponade in this patient. Thus, in order to optimize clinical outcome, clinicians must consider early, precautionary surgical management in patients who have sudden cardiac failure due to aortic regurgitation associated with prolapse of the bicuspid aortic valve.

Aged↗
PubMed2001

Postoperative myocardial ischemia in thoracic aortic aneurysms.

BACKGROUND: To determine the incidence and predictors of postoperative myocardial ischemia in non-coronary risk patients undergoing surgery for thoracic aortic aneurysms. METHODS DESIGN: a prospective, observational study. SETTING: a general intensive care unit in a university hospital. PARTICIPANTS: twenty patients without ischemic heart disease, scheduled for elective surgical repair of thoracic or thoracoabdominal aortic aneurysms. INTERVENTIONS: all patients underwent aortic replacement with prosthetic graft and routine postoperative care. Patients who developed myocardial ischemia received an infusion of coronary vasodilators. RESULTS: ECG episodes of myocardial ischemia were defined as reversible ST-segment changes of either >1 mm of depression or >2 mm of elevation at the J point. All patients survived operation. Eleven patients (ischemia group) developed myocardial ischemia, and 9 patients did not (non-ischemia group). These episodes were transient in 8 cases, but lasted longer than 3 days in 3 cases. In univariate analysis of perioperative factors between the two groups, the use of total cardiopulmonary bypass (p<0.01), the cardiac index at ICU admission (p<0.05), and the incidence of pre-existent hypertension (p<0.05) were significantly different. Multiple regression analysis identified the use of total cardiopulmonary bypass as the only predictor of myocardial ischemia. CONCLUSIONS: The use of total cardiopulmonary bypass is predictive of perioperative myocardial ischemia in surgery for thoracic aortic aneurysms, probably due to the production of proinflammatory cytokines by systemic ischemia and reperfusion. Prophylactic use of coronary vasodilators may be validated in these cases.

Adolescent↗
PubMed2001

Pathological evaluation of venous emboli during total hip arthroplasty.

One of the possible causes of bone cement implantation syndrome during total hip arthroplasty is pulmonary embolism, as has been suggested by a characteristic image seen during transoesophageal echocardiography, the so-called 'Snow Flurry'. However, the nature of the embolic material has not been definitively determined. We studied seven patients undergoing cemented or uncemented total hip arthroplasty. 'Snow Flurry' images were detected in all patients. Blood was aspirated from the right atrium during 'Snow Flurries' and was subjected to pathological examination. Amorphous, eosinophilic, fine granular material was seen in all specimens. The material did not originate from cement. Fat and bone marrow were not detected. The material seen may consist of fine particles of bone ('bone dust') originating from reamed bone.

Adult↗
PubMed2001

Diagnosis of deep vein thrombosis using platelet scintigraphy.

PURPOSE: We reviewed the usefulness of platelet scintigraphy, in which autologous platelets labeled with indium-111-oxine reveal thrombotic activity, for evaluating deep vein thrombosis (DVT). MATERIALS: During the past 2 years, 39 cases with DVT were enrolled in this study. DVT was definitely diagnosed by color duplex scanning, platelet scintigraphy or both in all cases. For semiquantitative analysis, we estimated the ratio of accumulation in the abnormal region to that in the normal vein on the other side, and defined an abnormal accumulation ratio as over 1.2. RESULTS: Abnormal accumulation ratio showing active DVT was recognized in 30 cases (77%), and showed a good correlation with clinical symptoms. In addition, in 19 cases with crural DVT, platelet scintigraphy showed abnormal accumulation ratio in 16 cases (84%), while duplex scanning detected thrombi in 13 cases (68%). In cases with abnormal accumulation ratio, thrombolytic and anticoagulant therapy were very effective for improving clinical symptoms as well inducing regression of the accumulation ratio. CONCLUSIONS: Platelet scintigraphy was very useful for the diagnosis and treatment of DVT and for evaluation of the effect of anticoagulant therapy. Limitations in the definite diagnosis of deep vein thrombosis (DVT) have been apparent for more than three decades. During the last decade, duplex scanning has reached a high level of accuracy and has been considered the gold standard in the diagnosis of DVT, instead of venography. However, duplex scanning and venography demonstrates only the anatomic alterations associated with venous lesions. In contrast, in platelet scintigraphy, the labeled platelets are incorporated directly into the thrombus and can reveal thrombus activity. We noticed that autologous platelets labeled with indium-111-oxine accumulated on fresh lesions of DVT. This observation suggested two applications of this technique: 1) evaluation of the role of platelets in the pathophysiologic characteristics of DVT; and 2) monitoring the effects of anticoagulant therapy.

Adult↗
PubMed2001

Isolation, culture, and characterization of endocrine cells from 6-month-old porcine pancreas.

Porcine endocrine cells were isolated from pancreas of 6-month-old pigs by two-step enzymatic digestion procedures. They were separated by the density gradient (isopycnic) centrifugation method using Histopaque-1077. Isolated cells were cultured and divided into two groups: suspension cells and adhesion cells. Suspension cells maintained their cell numbers on and after 7 days in culture. Approximately 1 x 10(7) cells were obtained from single pancreas of a 6-month-old pig. The cultured suspension cells took up dithizone (DTZ) staining 14 days after isolation in culture and indicated the presence of beta-cells. In in vitro study, the suspension cells were capable of secreting insulin into the culture medium. The suspension cells were tested for insulin and glucagon staining by Western blot analysis. These results indicated the maintenance of endocrine cell function after isolation. However, cultured adhesion cells failed to maintain their function during culture. In in vivo study, the suspension cells were transplanted into diabetes-induced nude mice. Reduction in blood glucose level was obtained after transplantation. Intraperitoneal glucose tolerance test (IPGTT) results showed a normal pattern of blood glucose clearance. After 1 week, the transplanted endocrine cells were detected with anti-insulin antibody by immunostaining and it showed the presence of viable beta-cells under the renal capsule of nude mice. Collectively, our results suggest that isolated and cultured suspension porcine endocrine cells maintained their endocrine function. These endocrine cells can be used as isolated islets for further study, including transplantation experiments.

Animals↗
PubMed2001

[Emergent surgical treatment of type A acute aortic dissection in an elderly patient].

An 86-year-old man with severe chest pain and shock was transferred to our hospital. Computed tomography revealed type A aortic dissection with cardiac tamponade. He needed intubation and closed chest massage preoperatively. At operation, intrapericardial space was filled with clotted blood and rupture of the ascending aorta was confirmed. He underwent a successful emergency graft replacement of the ascending aorta. Postoperative course was uneventful except for mild hemianopsia due to cerebral infarction. He had recovered to be able to walk and is doing well.

Acute Disease↗
PubMed2001

[Early diagnosis and therapy of deep venous thrombosis with 111 indium labeled platelets].

Clinical assessment of platelet scintigraphy by using autologous platelet labeled with 111-indium oxine to detect thrombotic activity for deep vein thrombosis. Platelet accumulation on scintigrams had a tendency to correlate with aggravation of acute thrombotic symptoms in deep vein thrombosis. This method was a useful procedure to make early diagnosis of deep vein thrombosis by detecting of abnormal accumulation of platelet. In addition, appropriate thrombolytic and anticoagulant therapy resulted in reduced platelet accumulation in conjunction with improvement of acute clinical symptoms. Thus, platelet scintigraphy could be available to evaluate thrombotic activity and might be useful for determining the optimal indications of thrombolytic and anticoagulation therapies for acute deep vein thrombosis. On the other hand, another kind of scintigraphy might be inevitable especially for detection of the pulmonary embolism. Anticoagulation therapy is also effective for pulmonary embolism.

Adult↗
PubMed2001

Large focal nodular hyperplasia of the liver: possible to evade surgical resection.

PURPOSE: Although recent advances in diagnostic imaging have allowed a number of patients with focal nodular hyperplasia (FNH) to avoid surgical treatment, the natural course of large FNH is still unknown. CASE REPORT: A 25-year-old man was admitted because of a large hepatic mass detected on routine examination in June 1998. The only laboratory abnormality was an elevated gamma-GTP. Computed tomography, angiography, positron emission tomography using F-18 fluorodeoxyglucose (FDG-PET), and scintigraphy using technetium-99m-galactosylneoglycoalbumin(99mTc-NGA) demonstrated a spoke-wheel appearance of vessels, normal hepatocytes, and no malignancy. Histologic findings on needle biopsy were consistent with FNH. After informed consent, the patient agreed to observation. Two years after the initial diagnosis, he has no symptoms, and there are no changes in the size or character of the lesion on computed tomography. DISCUSSION: Careful observation of patients with FNH is required because its natural course is unknown and these lesions can bleed or rupture.

Adult↗
PubMed2001

[Transdermal microparticle delivery by a supersonic-Helios gun system].

AIM: To investigate the effect of particle size and high speed flow of helium gas on the systemic absorption of indomethacin using a needle-less injection system. METHODS: Poly-L-lactic acid microspheres containing indomethacin was prepared by the o/w solvent evaporation technique. After anesthetizing the male hairless rat, microspheres filled in the tube cartridge was accelerated by a stream of helium gas at various velocity in the Helios gun system, and then was introduced to the abdominal skin. RESULTS: Introduction of indomethacin to the hairless rat skin was proportionally increased with enhancing the helium pressure (supersonic flow). Bioavailability and Cmax were also dependent on the helium pressure. CONCLUSION: This method can be used to deliver the powered drug and/or microparticulate systems into the skin tissues and the systemic circulation.

Administration, Cutaneous↗
PubMed2001

[Pharmaceutical evaluation of fast-disintegrant tablet containing nicorandil-loaded particles].

AIM: To improve the bioavailability and taste of fast-disintegrating tablet (FD tablet) containing nicorandil-loaded particles. METHODS: A FD tablet containing nicorandil-loaded particles with 1%-4% croscarmellose sodium in addition of D-mannitol and lactose (9:1) was prepared and the dissolution and absorption characteristics were examined, in comparison with FD tablet and commercial tablets of nicorandil. In vivo absorption of nicorandil from FD tablet was evaluated in beagle dogs. RESULTS: The disintegration time of FD tablets containing 1% croscarmellose sodium with 6 mm and 10 mm in diameter were about 12 and 23 seconds, respectively. When nicorandil-loaded particles consist of myristyl alcohol and stearyl alcohol were put in FD tablet, nicorandil release from FD tablet continued until 6 h while nicorandil release from Sigmart and FD tablet containing nicorandil crystals finished within 5 min. In vivo absorption of nicorandil from Sigmart and FD tablet containing nicorandil crystals was very similar after oral administration in beagle dogs and no statistic difference in AUC, Tmax, Cmax was observed between these tablets. However pharmacokinetics parameters of nicorandil after oral administration of FD tablet containing nicorandil-loaded particles showed that nicorandil was delivered into the body at a suitable absorption rate with similar AUC, delayed Tmax and lower Cmax. CONCLUSION: The reports suggest that the modification of properties of myristyl alcohol and stearyl alcohol released from the drug-loaded particles system would lead to more acceptable bioavailability of the system. However, The formulation of particles and may have a masking effect against the bitter taste and irritation of the drug.

Administration, Oral↗
PubMed2000

Total Synthesis of (+)-Eurylene and (+)-14-Deacetyleurylene We thank K. Ujihara (Sumitomo Chemical Co.) for generously supplying an authentic sample and a copy of the (1)H NMR spectrum of synthetic eurylene. We are grateful to Prof. H. Iio and Dr. Y. Usuki (Osaka City University) for the HPLC purification. T.I. thanks the Japan Society for the Promotion of Science for providing a JSPS Research Fellowship for Young Scientists. This research was supported by the Naito Foundation, the Fujisawa Pharmaceutical Award in Synthetic Organic Chemistry, Japan, the SUNBOR GRANT from the Suntory Institute for Bioorganic Research, and a Grant-in Aid for Encouragement of JSPS Research Fellows from the Japan Society for the Promotion of Science.

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Journal Article↗
PubMed2000

A reverse transcriptase-polymerase chain reaction assay in the diagnosis of soft tissue sarcomas.

BACKGROUND: Many types of sarcomas are characterized by specific chromosomal translocations that result in the production of novel chimeric genes. Detection of these fusion genes could be a sensitive molecular diagnostic assay. However, to the authors' knowledge there have been few systemic comparisons between the current histopathologic diagnosis and the presence or absence of particular fusion genes in patients with adult soft tissue sarcomas (STSs). METHODS: Total RNA was extracted from 75 cases of STS and analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) assay for the detection of a variety of fusion transcripts. The results of the molecular assay were compared with standard histopathologic diagnoses. RESULTS: Of the 18 tumors diagnosed as synovial sarcoma, 17 (94%) expressed SYT-SSX chimeric transcripts. All nine myxoid liposarcomas were positive for FUS-CHOP fusion transcripts. Of the four cases of Ewing sarcoma, two had an EWS-FLI1 fusion transcript and one had an EWS-ERG fusion transcript. A clear cell sarcoma had a EWS-ATF1 fusion transcript. None of 19 cases of malignant fibrous histiocytoma nor 3 leiomyosarcomas contained a fusion transcript. Three cases with an initial diagnosis other than synovial sarcoma expressed a SYT-SSX fusion transcript. A review of the slides and additional examination showed that a diagnosis of synovial sarcoma was appropriate for these cases. There was a trend for biphasic synovial sarcoma to contain the SYT-SSX1 fusion. CONCLUSIONS: The authors believe RT-PCR assay for the detection of a specific fusion gene provides a useful tool for confirmation of the diagnosis of adult STS in diagnostically difficult cases and in retrospective studies.

DNA Primers↗
PubMed2000

Study of complement activation on well-defined surfaces using surface plasmon resonance.

It has been accepted that covalent immobilization of C3b on artificial materials is the most important step to initiate the complement activation. However, there are few studies that have directly demonstrated covalent immobilization of C3b on artificial surfaces. In this study, model thin layers were prepared by the self-assembled monolayer method to produce a surface covered with hydroxyl or methyl groups using mercaptododecane (CH(3)-SAM) and mercaptoundecanol (OH-SAM). Interactions of the complement system with the model surfaces were studied using a surface plasmon resonance instrument. The OH-SAM immobilized C3b, resulting in activating of the complement system through the alternative pathway in Veronal-buffered saline, but this surface did not activate the classical pathway. However, the OH-SAM could not activate the alternative pathway in Veronal-buffered saline containing 10 mM EGTA and 2 mM MgCl(2) that is believed not to interfere with the activation of the alternative pathway. The hydrophobic CH(3)-SAM surface could not activate the classical pathway, but activated the alternative pathway, although the extent was small.

Journal Article↗