Biomedical subjects

M Okazaki

Publications and source records attributed to M Okazaki.

At least 109 records · Page 6Linked to original sources

PubMed2000

Duration of systemic corticosteroids in the treatment of asthma exacerbation; a randomized study.

OBJECTIVE: To determine an appropriate duration for a short course of oral steroids in cases of asthma exacerbations. SETTING: A 1,000 bed city hospital in Kobe, Japan. PATIENTS: Patients with asthma exacerbations who needed hospital admission. METHODS: Following an initial treatment with a 3-day course of intravenous methylprednisolone, patients were allocated to either a 1-week (1 W) or a 2-week (2 W) course of oral prednisolone (PSL, 0.5 mg/kg). OUTCOME MEASURES: Peak expiratory flow rate (PEF) and rate of unscheduled hospital visits and readmission. RESULTS: Twenty patients were enrolled (10 in 1 W, 10 in 2 W). Mean PEF just before starting oral PSL in 1 W and 2 W were 51 and 58% of each patient's best value. PEF was significantly improved and to a similar degree over the course of time in both 1 W and 2 W. The frequency of unexpected hospital visits during a 3-month period after discharge was similar (2 in 1 W and 2 in 2 W). No readmission occurred during the same period. CONCLUSIONS: Because both the 1-week and the 2-week course of oral PSL were equally effective in the treatment of asthma exacerbations, 1 week may be appropriate as the maximum duration of a short rescue course of oral steroids.

Acute Disease↗

PubMed2000

Assessment of between-instrument variations in a HPLC method for serum lipoproteins and its traceability to reference methods for total cholesterol and HDL-cholesterol.

BACKGROUND: The main purpose of this study was to evaluate the between-instrument variation of the HPLC method for the measurement of total cholesterol (TC), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), VLDL-cholesterol (VLDL-C), chylomicron cholesterol (CM-C), LDL size, and HDL size. Furthermore, the accuracy of the HPLC was assessed for the determination of TC and HDL-C, compared with CDC reference methods. METHODS: We used four HPLC instruments with different column-load numbers from 250 to 5000. For accuracy assessment of TC and HDL-C, we used the reference methods recommended by the CDC. RESULTS: The values measured by the four instruments were highly correlated with each other (mean r = 0.965), and the absolute mean differences were 4-43 mg/L for TC, 4-30 mg/L for HDL-C, 0-48 mg/L for LDL-C, 7-66 mg/L for VLDL-C, 0-7 mg/L for CM-C, 0.1-0.3 nm for LDL size, and 0-0.1 nm for HDL size. For TC, the HPLC instruments showed high correlation and good agreement with the reference method: r = 0.997; total error <6.6%; absolute mean bias <1.2%. For HDL-C, the results from the HPLC method were significantly higher (10.8% absolute mean bias) than those of the CDC reference method, in spite of good correlation between the two methods (r = 0.998). CONCLUSIONS: The between-instrument variation in serum lipoprotein analysis by HPLC was confirmed to be very small. This method met the US National Cholesterol Education Program's performance criteria for TC but not for HDL-C.

Cholesterol↗

PubMed2000

[Endoscopic approach to pulmonary diseases: Transbronchial needle aspiration].

Transbronchial needle aspiration (TBNA) is a bronchoscopic technique to obtain cytologic and histologic specimen from deep site of bronchial wall. We investigated the utility and safety of TBNA in 200 patients who had mass lesions in the lung or in the mediastinum. 101 patients had submucosal or peribronchial malignant lesions (central malignancy) and TBNA was the only diagnostic method in 28 patients (28%). 39 patients had peripheral malignant lesions (peripheral malignancy) and TBNA was the only diagnostic method in 12 patients (31%). The other 60 patients had benign lesions and TBNA was diagnostic in only 5 patients (8%); bronchogenic cyst in 2, tuberculous lymph adenitis in 1, parathyroid adenoma in 1 and lung abscess in 1. In central malignancy, the yield of TBNA as exclusive means of diagnosis was higher for mediastinal tumor than for lung cancer. In peripheral malignancy it was higher for metastatic lung tumor than for primary lung tumor. In order to stage patients of lung cancer, we sampled 39 lymph nodes and 21 of them were proved to be positive. TBNA was thought to be of greatest value in the diagnosis of peritracheal mediastinal tumor and peribronchial metastatic lung tumor and in the staging of lung cancer. We used 19-gauge transbronchial histology needle in 8 patients and 2 cases were diagnostic. Low diagnostic yields were probably due to the lack of our experience and it was expected that training on this technique would increase diagnostic utility of the histology needle. No significant complications occurred and all patients tolerated TBNA well.

Biopsy, Needle↗

PubMed2000

[Clinical study of selective intra-arterial infusion chemotherapy using trans-radial arterial approach in 4 cases of advanced breast cancer].

We administered neoadjuvant chemotherapy by a selective intra-arterial infusion method using a trans-radial approach in patients with advanced breast cancer (stage III and stage IV). The trans-radial approach uses the arterial flow, based on the Seldinger technique. In this method, the radial artery is cannulated, and epirubucin is infused into the artery that carries blood from the subclavical artery to the breast. We have used this method in 4 cases thus far. Two of the patients received a single intra-arterial infusion of epirubicin. The other 2 patients were catheterized before they received chemotherapy by intra-arterial infusion. This technique decreased the pain or discomfort caused by the catheterizations during chemotherapy in all 4 cases. However, the currently available catheters are not always able to approach the artery flowing into the breast, thus the protocol will need to be refined.

Adenocarcinoma, Scirrhous↗

PubMed2000

[Detectability of metastatic brain tumors using gadoteridol-enhanced MRI: usefulness of standard-dose T1-weighted spin-echo image with magnetization transfer and enhanced FLAIR].

PURPOSE: The aim of this study was to compare the detectability and image contrast of metastatic brain tumors depicted by T1-weighted MR imaging (T1WI) with the magnetization transfer (MT) technique after the administration of a standard dose(MT-SD-T1WI) or T1WI without MT after the administration of a double dose of gadoteridol(DD-T1WI). We also assessed the usefulness of enhanced fluid attenuated inversion recovery (FLAIR) for depicting very small metastatic tumors. METHODS: Forty-six MRI procedures were performed in 31 patients with metastatic brain tumors that had been diagnosed clinically and radiologically. An incremental dose technique was used with intravenous injections of 0.1 and 0.1 mmol/kg of gadoteridol. In 28 MRI procedures, enhanced FLAIR was carried out after an MT-SD-T1WI study. RESULTS: Detectability was significantly greater with both MT-SD-T1WI and DD-T1WI than with SD-T1WI. However, there was no significant difference between MT-SD- and DD-T1WI. Although an MT pulse increased the contrast between the enhanced tumor and white matter, the contrast between edema and white matter was decreased. Both MT-SD- and DD-T1WI showed small but conspicuous enhanced foci, but we could not determine whether these were vessels or small metastases on the brain surface. However, enhanced FLAIR only demonstrated foci that were thought to be small metastases. CONCLUSIONS: MT-SD- and DD-T1WI had equal ability to detect metastatic brain tumors. Enhanced FLAIR was useful for assessing very small metastases on the brain surface.

Adult↗

PubMed2000

[Impact of discontinuing peak flow monitoring in stable asthma].

We conducted a prospective study to examine the influence of discontinuing peak flow monitoring (PFM) in stable asthmatics who had already been properly educated and were monitoring their own peak expiratory flows (PEF). All subjects had been performing PFM for at least 3 months prior to their entry into the study, and PFM was then stopped for a period of 3 months. Comparisons of endpoints were made between a period of 3 months prior to, and after discontinuing PFM. Forty patients with a mean age of 52 were studied. Only one patient experienced a single emergency room visit either before or after discontinuing PFM. Short courses of oral steroids were administered in 6 patients (15%), both before and after discontinuing PFM. There was no significant change in pulmonary function, beta 2-agonist use and asthma symptoms during a 3-month period before and after discontinuing PFM. These results suggest that simply continuing PFM in stable, educated asthmatics may have little impact on asthma control, although its long term influence should be carefully examined.

Adrenergic beta-Agonists↗

PubMed2000

Intramedullary clear cell ependymoma in the cervical spinal cord: case report.

OBJECTIVE AND IMPORTANCE: Clear cell ependymoma of the spinal cord has not been reported in the literature, although ependymoma in the cerebral and cerebellar hemispheres has been described. We present the first case report of this rare histological type of ependymoma arising in the cervical spinal cord and emphasize the importance of recognizing this histological entity. CLINICAL PRESENTATION: A 42-year-old woman presented with numbness in both upper limbs and spastic gait. Magnetic resonance imaging revealed an intramedullary tumor at the C6-T1 level with syringomyelia. INTERVENTION: The tumor was totally removed. Histological analysis revealed that the tumor was composed of round cells with perinuclear halos similar to those observed in oligodendroglioma. However, we diagnosed clear cell ependymoma because these tumor cells exhibited epithelial features and ependymal rosettes under light microscopic examination. CONCLUSION: Histological diagnosis was crucial to our determining whether to perform postoperative adjuvant therapy in this patient. Neurosurgeons should be aware of the possibility of this histological entity among intramedullary spinal cord tumors.

Adult↗

PubMed2000

[Radiation exposure to patient and radiologist during transcatheter arterial embolization for hepatocellular carcinoma].

PURPOSE: To evaluate radiation exposure to patients and radiologists during transcatheter arterial embolization(TAE) for hepatocellular carcinoma. MATERIALS AND METHODS: In 39 TAE procedures performed at eight institutes, skin doses were evaluated with thermoluminescence dosimeters at the patient's back(entrance surface) and lower abdomen, and at the radiologist's forehead and abdomen. Real-time dosimeters were also used to evaluate patient skin dose. RESULTS: The patients' mean entrance surface dose was 973 +/- 681 mGy(range, 185 to 3543 mGy) with the mean fluoroscopic time of 21 minutes and 6 digital subtraction angiography(DSA) acquisitions. The dose at the patients' lower abdomen was 0.98 +/- 0.77 mGy. Doses for the radiologists were 0.04 +/- 0.04 mGy at the forehead and 0.15 +/- 0.19 mGy and 0.005 +/- 0.01 mGy at the abdomen over and under the apron, respectively. Fifty-six percent of the patients' skin dose was from DSA and 44% from fluoroscopy. CONCLUSIONS: Patient skin dose may occasionally exceed the dose for transient erythema. Because a patient may have repeated TAEs, skin doses or X-ray conditions should be recorded. The exposed doses of radiologists were considered to be acceptable with proper techniques. Further efforts to reduce radiation should be directed toward both DSA and fluoroscopy.

Aged↗

PubMed2000

Serum extracellular superoxide dismutase in pediatric patients with various diseases as judged by an ELISA.

Extracellular superoxide dismutase (EC-SOD) concentration was measured in sera from 141 patients with 20 forms of infantile diseases including IDDM, SLE and epilepsy, 31 healthy children (controls), and 21 healthy young men by an enzyme-linked immunosorbent assay using a polyclonal antibody against human lung EC-SOD. Serum from patients with IDDM and fever of unknown origin had a significantly (p<0.05) lower concentration of EC-SOD than control serum. Part of sera from patients with the seven forms of diseases (SLE, viral infections, epilepsy, nephrosis, hyperthyroidism, hepatic disease, and Reye syndrome), on the other hand, had a greatly high concentration of EC-SOD, albeit not statistically significant. This SOD isoenzyme profile appears to be specific to each pediatric disease.

Adolescent↗

PubMed2000

Current and future therapies for ischemic cerebrovascular disease.

Stroke is the third leading cause of death in the adult population. It makes great demands on patients, who must not only survive the complications of the acute stages but also must cope with the great physical and economic costs of long-term disabilities. Therefore, there is an urgent need to establish generally useful treatments for ischemic stroke. Currently, there are three treatment approaches based on pathophysiologic concepts derived from basic research: (i) pharmacologic strategies for arterial recanalization, (ii) neuronal protection and (iii) the inhibition of undesirable damaging host responses. The key to current treatment is the emergent administration of tissue plasminogen activator (t-PA). Thrombolytic treatment improves outcome when given to carefully selected patients within 3 h of stroke onset. Numerous neuroprotective agents have been developed in the last decade, and a new wave of therapies is now on the horizon that could potentially minimize ischemic brain damage. This article highlights recent advances in pharmacological interventions for ischemic stroke.

Journal Article↗

PubMed1999

Changes in mRNA levels of fibrinogen subunit polypeptides in rats defibrinogenated with batroxobin.

Batroxobin is a snake venom that is a thrombinlike enzyme used for clinical treatment. We analyzed hepatic mRNA levels for fibrinogen subunit polypeptides and prothrombin by reverse transcription-polymerase chain reaction as well as coagulation and fibrinolysis factors in plasma 1, 3, 5 and 24 hours after Batroxobin treatment (3 BU/100 g) in rats. The mRNA levels of alpha- and beta-chains of fibrinogen were significantly increased with decreases in plasma fibrinogen, alpha2-plasmin inhibitor, and plasminogen levels, while the mRNA levels for prothrombin remained unchanged. These results suggest that fibrinogen mRNA synthesis is regulated by plasma fibrinogen levels in Batroxobin-induced defibrinogenated rats.

Animals↗

PubMed1999

Hypofibrinogenemia associated with a heterozygous missense mutation gamma153Cys to arg (Matsumoto IV): in vitro expression demonstrates defective secretion of the variant fibrinogen.

We genetically analyzed a case of hypofibrinogenemia that showed no bleeding or thrombotic tendency. Direct sequencing of a polymerase chain reaction-amplified gamma-chain gene segment showed a novel nucleotide substitution. This heterozygous mutation encodes both Cys (TGT) and Arg (CGT) at residue 153. To examine the basis for the fibrinogen deficiency, we prepared expression vectors containing mutant gamma-chain DNAs encoding gamma153R and gamma153A for in vitro expression in Chinese hamster ovary (CHO) cells. Enzyme-linked immunosorbent assay and immunoblot analysis of the culture media and cell lysates showed that CHO cells transfected with gamma153R or gamma153A synthesized the variant gamma-chain, but did not secrete variant fibrinogen into the culture medium. Metabolic pulse-chase experiments showed that fibrinogen assembly was impaired when either variant gamma-chain was expressed. In cells expressing normal fibrinogen, assem- bly intermediates and intact fibrinogen were seen in cell lysates prepared after short (3 minutes) or long (1 hour) incubation with (35)S-methionine. Neither intermediates nor intact fibrinogen was seen with the variant gamma-chains. These data suggest that gamma-chains have an important early role in fibrinogen assembly. Thus, our results support the model for fibrinogen assembly proposed by Huang et al (J Biol Chem 268:8919, 1993), in which the first step in assembly is the formation of alphagamma or betagamma dimers, or both. This model implies that gammaCys153 has a critical role in the formation of these early assembly intermediates. We concluded that the gamma153Cys-->Arg substitution does not allow fibrinogen assembly and secretion, and this is manifest in vivo as a fibrinogen deficiency. We designated this variant as fibrinogen Matsumoto IV.

Adult↗

PubMed1999

Cloning, expression profile, and genomic organization of the mouse STAP/A170 gene.

The preferential screening of cDNA libraries derived from the mouse osteoblastic cell line MC3T3-E1 has yielded a cDNA clone encoding a 442-amino-acid protein designated STAP (signal transduction and adaptor protein), which contains several motifs shared among transcription factors and adaptors such as a Zn-finger like motif, a proline-rich domain, and a PEST sequence. The amino acid sequence homology search also reveals that STAP is identical to a mouse oxidative stress protein, A170, and has 90% homology with a human p62 protein that binds to the tyrosine kinase p56(lck) SH2 domain. Northern blot analysis indicated a broad expression profile of STAP mRNA in various tissues and cell lines. In MC3T3-E1 cells, STAP mRNA was induced by treatment with TGF-beta, but not with BMP-2 or GDF-5. Analysis of the mouse STAP gene isolated from the genomic library revealed that the STAP gene spans a region of over 11 kb and comprises eight exons. The transcription start site was identified by primer extension analysis to be located 35 bp upstream from the translation initiation site. Sequencing analysis of the 5' flanking region of the STAP gene revealed multiple consensus motifs/sequences for several DNA binding transcription factors. The STAP gene had a TATA box, but no CCAAT box. Potential Sp1, AP-1, NF-E2, MyoD, and NF-kappaB binding sites were found in the 5' flanking region (1.4 kb) of the STAP gene.

3T3 Cells↗

PubMed1999

Kainic acid-induced inducible cyclooxygenase and c-Jun phosphorylation in the rat hippocampal formation.

Inducible cyclooxygenase (COX-2) was transiently induced in the neurons throughout the entire hippocampus between 6 and 24 h after injection of kainic acid (KA). The induction of COX-2 correlated more closely with the induction of c-Jun than with that of c-Fos. Phosphorylated c-Jun was induced 6-12 h after in the CA3 pyramidal neurons, which undergo apoptosis. Almost all of neurons with phosphorylated c-Jun were colocalized with COX-2. These results suggest that COX-2 and c-Jun phosphorylation may participate in KA-induced neurodegeneration.

Animals↗

PubMed1999

Developmental expression of P-glycoprotein (multidrug resistance gene product) in the rat brain.

P-Glycoprotein (PGP), a product of the multidrug resistance gene (mdr), acts as an adenosine triphosphate-dependent drug efflux system in cells. Initially, PGP was found in cancer cells, but it is now known that PGP is richly distributed in the adult brain. Passage to the central nervous system is limited by the blood-brain barrier (BBB), and mdr1 gene-deficient mice showed up-regulation of BBB permeability. In this study, we examined the expression and localization of PGP in the rat brain during development. PGP protein was predominantly detected in the membrane fraction of the adult rat brain, although it was also faintly detected in the cytosolic fraction. PGP protein in the membrane fraction was undetectable in the embryo and early stages of postnatal development by immunoblotting studies, was first detected on postnatal day (P) 7, and then gradually increased to reach a plateau. Such changes were observed commonly in the cerebral cortex, hippocampus, and cerebellum. Immunohistochemical studies showed that PGP immunoreactivity was first detected on P7, and intense PGP immunoreactivity was observed in the adult rat brain. Double-immunolabeling studies revealed that PGP was colocalized with von Willebrand factor-immunoreactive capillaries. We further examined the colocalization of PGP and astrocytes using glial fibrillary acidic protein (GFAP) as a marker. Three-dimensional analysis showed that the GFAP-immunoreactive astrocytes possessed fine processes which ensheathed capillaries, but the PGP immunoreactivity did not colocalize with the GFAP immunoreactivity. These results indicate that PGP expression increased with postnatal development and is localized in the brain capillaries.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1999

The NH2-terminal region of the active domain of sonic hedgehog is necessary for its signal transduction.

The NH2-terminal domain of sonic hedgehog (residue 25-198) was expressed in both yeast and animal cells. The yeast-derived NH2-terminal domain of sonic hedgehog was less active by far than the animal cell-derived counterpart. The yeast-derived NH2-terminal domain of sonic hedgehog lacked 10 amino acids from the NH2-terminus. This cleavage of the yeast-derived NH2-terminal domain of sonic hedgehog might due to Kex 2. In contrast, a mutant yeast-derived NH2-terminal domain of sonic hedgehog (Lys-33 to Thr) retained its NH2-terminus and its activity was comparable to that of the animal cell-derived NH2-terminal domain of sonic hedgehog. The NH2-terminal deleted NH2-terminal domain of sonic hedgehog completely lost its activity, nevertheless it inhibited the alkaline phosphatase activity induced by the animal cell-derived NH2-terminal domain of sonic hedgehog in a dose-dependent manner. These data suggest that the NH2-terminal deleted NH2-terminal domain of sonic hedgehog retains a receptor-binding ability and that the NH2-terminal peptide of the NH2-terminal domain of sonic hedgehog is necessary for its signal transduction.

Alkaline Phosphatase↗

PubMed1999

Cloning and characterization of a new exo-cellulase gene, cel3, in Irpex lacteus.

A new cellulose-inducible gene (named cel3) was isolated from a strain of the white rot basidiomycete, Irpex lacteus MC-2. The cel3 open reading frame, containing two introns, encodes a polypeptide of 526 amino acids residues with a molecular mass of 55794 Da. Expression of the cel3 gene was induced by various insoluble celluloses and CM-cellulose. Transcription of cel3 was abolished when cells were cultivated in media containing the above cellulosic substrates, but added with glucose, fructose or lactose, while addition of glycerol or mannitol did not affect the cel3 mRNA level. The amino acid sequence of the catalytic domain of the Cel3 protein was homologous to that of fungal exo-type cellulases belonging to family 7 of the glycosyl hydrolases. A phylogenetic study showed that these exo-type cellulases can be clearly separated from family 7 endo-type cellulases.

Amino Acid Sequence↗

PubMed1999

Volume Changes Due to SO2-4, SeO2-4, and H2PO-4 Adsorption on Amorphous Iron(III) Hydroxide in an Aqueous Suspension.

Volume changes due to SO2-4, SeO2-4, and H2PO-4 adsorption on amorphous iron(III) hydroxide were determined by dilatometry in a mixture comprising an aqueous solution of Na2SO4, Na2SeO4, or NaH2PO4 and amorphous iron(III) hydroxide suspended in 0.1 mol dm-3 NaClO4 at an initial pH ranged from 4.50 to 6.50. System volumes increased during SO2-4, SeO2-4, and H2PO-4 adsorption on amorphous iron(III) hydroxide, suggesting that some hydrated water around aqueous SO2-4, SeO2-4, or H2PO-4 ions and amorphous iron(III) hydroxide were released to the bulk. The volume changes due to SO2-4, SeO2-4, and H2PO-4 adsorption at initial pH 4.50 were +18, +18, and +14 cm3 mol-1, respectively. Phosphate, which adsorbed as an inner-sphere complex, released most of its hydration water to the bulk. The volume changes due to SO2-4 and SeO2-4 adsorption indicated that they were dehydrated at the water/amorphous iron(III) hydroxide interface. The smaller changes in volume for H2PO-4 compared to SO2-4 and SeO2-4 may be explained by differences of charges and adsorption mechanisms of these oxoanions. Copyright 1999 Academic Press.

Journal Article↗