Biomedical subjects

M Okada

Publications and source records attributed to M Okada.

At least 73 records · Page 4Linked to original sources

PubMed2002

Superior vena cava syndrome after bone marrow transplantation caused by aspergillosis: a case report.

Aspergillosis is known for the variety of unusual presentations in immuno-suppressed patients. We report a patient in whom aspergillosis caused the superior vena cava (SVC) syndrome. A 37-year-old woman became febrile soon after bone marrow transplantation (BMT). Chest radiography demonstrated a 5-cm mass extending from the right lung apex to the right supraclavicular fossa beside her Hickman catheter. She then developed SVC syndrome, which progressed despite treatment. Despite recovery of the white blood cell count, the patient continued to deteriorate, became comatose, suffered a cardiac arrest and died 31 days after BMT. Autopsy revealed Aspergillus infection at the apex of the right lung associated with innominate artery thrombosis.

Adult↗

PubMed2002

Anticholinergic drugs: response of parkinsonism not responsive to levodopa.

A 41 year old man with parkinsonism and pyramidal signs is described. He was non-responsive to levodopa and dopamine receptor agonists but dramatically responded to trihexyphenidyl. In this patient, brain MRI showed bilateral hyperintensities along the corticospinal tracts on T2 weighted images. PET studies showed a decrease in (18)F-6-fluorodopa uptake in the putamen contralateral to the more affected limbs and normal D(2) receptor binding in the putamen. The PET and MRI findings and responsiveness to antiparkinsonian agents suggested degeneration of nigrostriatal dopaminergic neurons, striatal output pathways, and corticospinal tracts.

Adult↗

PubMed2002

Differential display of protein tyrosine kinase cDNAs from human fetal and adult brains.

Here we describe a differential display method for surveying the expression of most protein tyrosine kinases and applying it to cDNAs from human fetal and adult brains. The method involves two selective steps for processing the mRNA. At each step, degenerate oligonucleotide primers derived from highly conserved regions of the catalytic domain of the kinases are used. In the display with BstYI and BsiHKI digests of the cDNA, 65% and 59% of a total of 72 and 63 bands, respectively, represented fragments from a total of 27 different tyrosine kinases. The expression levels of the kinases in the display were comparable with those measured by RT-PCR. This method offers a relatively specific way to display differentially expressed gene families in any tissue and cell type.

Adult↗

PubMed2002

Nephropathy of cyanotic congenital heart disease: clinical characteristics and effectiveness of an angiotensin-converting enzyme inhibitor.

AIMS: Nephropathy has long been recognized as a potential complication of cyanotic congenital heart disease (CCHD). There have been few large-scale studies or clinical reports on renal impairment in patients with CCHD; similarly, very few studies have examined the drug treatment of nephropathy in CCHD. We examined the clinical characteristics and effectiveness of enalapril, an angiotensin-converting enzyme inhibitor (ACE-I), in patients with CCHD complicated with significant proteinuria. MATERIALS AND METHODS: The clinical records of 37 patients with CCHD were evaluated; all were older than 10 years of age (median 19, range from 10 to 27) and had regular check-ups, including urinalysis. The treatment criteria for enalapril administration included significant proteinuria (urinary excretion > 1.0 g/24 h), stable cardiac condition and blood pressure within the normal range. RESULTS: Eleven patients (29.7%) had persistent proteinuria, 6 patients met the enalapril treatment criteria and 5 patients were treated for more than 12 months. Enalapril apparently reduced the urinary protein excretion in 4 of the 5 patients (80%). No consistent improvement of renal function, as evidenced in the glomerular filtration rate (GFR), renal plasma flow (RPF) or filtration fraction (FF) was found in these patients, but neither were any significant adverse effects noted. CONCLUSION: The incidence of nephropathy among patients with CCHD was about 30%, which was consistent with previous studies. It is worth considering the use of ACE-I when nephropathy accompanies CCHD.

Adolescent↗

PubMed2002

[Coronary artery bypass grafting without cardiopulmonary bypass: MIDCAB and OPCAB].

Minimally invasive direct coronary artery bypass grafting via left anterior small thoracotomy (MIDCAB) and coronary artery bypass grafting without cardiopulmonary bypass (OPCAGB) are accepted technique as less invasive than conventional coronary artery bypass grafting (CABG). We reported our experience with these procedures. From 1996 to December 1999, 176 patients underwent MIDCAB or OPCAB with the internal thoracic artery. The left internal thoracic arteries were used for grafting of the left anterior descending artery (LAD) in 131 patients, LAD and diagonal branches sequentially in 8 patients, using free radial artery conduits for grafting of the right coronary artery (RAC) or left circumflex (LCx) in 7 patients, using radial artery conduits as Y-graft from LAD for grafting of the RAC or LCx in 24 patients, and bilateral internal thoracic artery grafting was performed in 4 patients. One patient (0.6%) died in the hospital. One patient (0.6%) had perioperative myocardial infarction. No patient had cerebrovascular accident and sever wood infection. One-hundred-seventy-four patients (98.8%) had resolution of their angina symptom.

Adult↗

PubMed2002

Oral eicosapentaenoic acid for acute colonic graft-versus-host disease after bone marrow transplantation.

We investigated whether pretreatment with eicosapentaenoic acid, an inhibitor of leukotriene (LT) B4, could ameliorate acute colonic graft-versus-host disease (GVHD) after bone marrow transplantation (BMT). Seventeen patients undergoing unrelated BMT were divided into two groups, with eight patients receiving eicosapentaenoic acid and nine not receiving it. The grade of GVHD after transplantation was compared with that estimated from the pretransplantation LTB4 level. The levels of LTB4 and several cytokines were also monitored. The actual grade of GVHD was lower than that estimated from LTB4 levels in three of the eight patients from the treated group, and there was a significant difference between the treated and untreated groups (p < 0.05, chi 2 test). The levels of LTB4, tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) were all significantly lower in the treated group (p < 0.05, Student's t-test). These findings suggest that eicosapentaenoic acid may ameliorate acute colonic GVHD when administered from before BMT.

Acute Disease↗

PubMed2002

[Rice-wheat rotational FACE platform. I. System structure and control].

A Free Air CO2 Enrichment (FACE) system for rice and winter wheat rotation was established, elevated CO2 concentration was controlled to 200 mumol.mol-1 above ambient by computer system platform according to ambient CO2 concentration variation, wind direction, wind speed, canopy height and day-night changing. Experiments showed that the main factors affecting control precision are wind speed, crop and soil respiration and thickness of diffuse layer. After parameters adjustment, in daytime the time fraction for control precision achieve 80% is 83%, in night is 68%. The CO2 concentrations distribution in FACE rings are uniformity. The set CO2 is 557 mol.mol-1 in daytime and 608 mol.mol-1 in night. In 2001 rice season the target achievement ratios (TAR) were 1.03 after sunrise and 1.09 after sunset, respectively.

Agriculture↗

PubMed2002

[Rice-wheat rotational FACE platform. II. Data processing software package].

A large amount data are brought from daily control, data collection and processing of FACE platform. A FACE system control, data collection and processing software package written in Visual BASIC including OLE to support office functions can finish the platform control, data collection, original data save and backup, daily data processing, monthly data processing and whole time FACE system control status analysis functions, so FACE system controllers can observe FACE system control status and keep control precision timely, and the researchers can get the data they want at any moment and convenient.

Air↗

PubMed2002

[Functional diagnosis with color ultrasound in occlusion of peripheral arteries].

In recent years the number of the patients with occlusive disease of the peripheral arteries is increasing also in Japan. For such patients there are many methods to make final diagnosis. Among a lot of methods we have chosen color duplex sonography for functional diagnosis in the patients with occlusive disease of the peripheral artery. During 2 years we have investigated color duplex sonography in addition to digital subtraction arteriography for 40 patients (68 limbs) with occlusive disease of the peripheral artery. First of all waveform of blood flow and the systolic velocities of the dorsal- and the posterior tibial arteries as well as the brachial artery were observed and measured. The blood flow volume and the ratio of systolic velocities and flow volume of lower to upper extremity (AVI, AFI) were measured and their values were also analysed in each patient. These data were compared with Fontaine's classification as a clinical symptom. For the patients with Fontaine class I, or II conservative treatments were carried out, and operative interventions such as bypass graft, or endovascular operation were carefully performed for the patients with Fontaine's class III or IV. Consequently, clinical symptoms and waveforms of systolic flow, and its velocity were remarkably improved by surgical interventions. Thus, color duplex sonography was a useful procedure to make diagnosis and to decide operative indication in the patients with occlusive disease of the peripheral artery.

Adult↗

PubMed2001

Neutralization of interleukin-1beta in the acute phase of myocardial infarction promotes the progression of left ventricular remodeling.

OBJECTIVES: We sought to examine the role of the pro-inflammatory cytokine, interleukin-1-beta (IL-1beta), in the process of left ventricular (LV) remodeling in the early phase after myocardial infarction (MI). BACKGROUND: Studies have shown that pro-inflammatory cytokines are closely related to the progression of LV remodeling after MI. METHODS: Mice underwent coronary artery ligation, and the time course of LV remodeling was followed up to 20 weeks. The gene expression level of IL-1beta was examined. In a second set of experiments, the mice underwent coronary artery ligation followed by treatment with anti-IL-1beta antibody (100 microg, intravenously), versus control immunoglobulin G (100 microg, intravenously) immediately after the operation. RESULTS: Rapid hypertrophy of noninfarcted myocardium was observed by four weeks, and interstitial fibrosis progressed steadily up to 20 weeks. Anti-IL-1beta treatment increased the occurrence of ventricular rupture and suppressed collagen accumulation in the infarct-related area. At four and eight weeks after the operation, total heart weight and LV end-diastolic dimension were significantly greater in the anti-IL-1beta-treated mice than in the other groups. In the infarct-related area, collagen accumulation was suppressed, whereas in the noninfarcted area, pro-collagen gene expression levels, particularly type III, were decreased in the anti-IL-1beta-treated mice. CONCLUSIONS: Anti-IL-1beta treatment suppressed pro-collagen gene expression and delayed wound healing mechanisms-properties that are likely to lead to progression of LV remodeling. In the acute phase of MI, IL-1beta appears to play a protective role.

Acute Disease↗

PubMed2001

Treatment of intestinal graft-versus-host disease using betamethasone enemas.

Intestinal graft-versus-host disease (GVHD) can readily easily induce generalized metabolic disturbance that influences morbidity and mortality after allogeneic bone marrow transplantation. Although adding a new drug or increasing the doses of immunosuppressive agents will probably be effective for controlling intestinal GVHD, the systemic side effects of such therapy cannot be ignored. In this study, we used betamethasone retention enemas as a local treatment for eight patients with refractory and/or severe intestinal GVHD. Six of the eight patients showed improvement of diarrhea and/or abdominal pain, with a reduction in the stage of GVHD. When treatment with betamethasone enemas was continued for 10 to 27 days in the 6 responding patients, no severe toxicity was observed. One patient failed to respond to treatment and another could not tolerate the enemas. Despite some uncertainty regarding the indications and duration of treatment, betamethasone enemas seem to be a potential alternative method for the management of intestinal GVHD.

Administration, Topical↗

PubMed2001

A novel protein interacts with a clock-related protein, rPer1.

Mammalian Per proteins are thought to be important in the mechanism of circadian rhythm. We identified a novel protein PIPS (Per1 interacting protein of the suprachiasmatic nucleus) with the yeast two-hybrid system using PAS domain of rat Per1 (rPer1) as a bait. PIPS is about a 180-kDa protein and expressed mainly in the brain, especially in the hypothalamus including the suprachiasmatic nuclei (SCN). PIPS interacts with mouse Per1 (mPer1) in vitro and in cultured cells transfected with both molecules. Furthermore, it was found that mPer1 translocated PIPS into the nuclei in the cultured cells. Thus, these findings suggest a possibility that PIPS is involved in the feedback loop or output mechanism of circadian rhythm through interacting with Per1 in the SCN.

Amino Acid Sequence↗

PubMed2001

Extinguishing Egr-1-dependent inflammatory and thrombotic cascades after lung transplantation.

Hypoxic induction of the early growth response-1 (Egr-1) transcription factor initiates proinflammatory and procoagulant gene expression. Orthotopic/isogeneic rat lung transplantation triggers Egr-1 expression and nuclear DNA binding activity corresponding to Egr-1, which leads to increased expression of downstream target genes such as interleukin-1b, tissue factor, and plasminogen activator inhibitor-1. The devastating functional consequences of Egr-1 up-regulation in this setting are prevented by treating donor lungs with a phosphorothioate antisense oligodeoxyribonucleotide directed against the Egr-1 translation initiation site, which blocks expression of Egr-1 and its gene targets. Post-transplant graft leukostasis, inflammation, and thrombosis are consequently diminished, with marked improvement in graft function and recipient survival. Blocking expression of a proximal transcription factor, which activates deleterious inflammatory and coagulant effector mechanisms, is an effective molecular strategy to improve organ preservation.

Animals↗

PubMed2001

TGF-beta-producing CD4+ mediastinal lymph node cells obtained from mice tracheally tolerized to ovalbumin (OVA) suppress both Th1- and Th2-induced cutaneous inflammatory responses to OVA by different mechanisms.

Advances in the treatment of allergic disorders require elucidation of the autoregulatory immune systems induced in averting detrimental inflammatory responses against invading foreign Ags. We previously reported that excessive Ags intruding through the airway mucosa induce a subset of regulatory CD4+ T cells secreting TGF-beta in the regional mediastinal lymph nodes (MLNs), which inhibits Th2 cells and subsequent eosinophilic inflammation in the trachea. In the present experiments we examined whether and in what mechanisms TGF-beta-secreting CD4+ T cells in the MLNs regulate Th cell-mediated skin inflammation using a previously established murine model. Th1 or Th2 cells injected s.c. into ear lobes of naive mice induced swelling, whereas the concomitant local injection of MLN cells suppressed the inflammation. The suppressor activities of MLN cells were markedly neutralized by anti-TGF-beta mAb and were mimicked by rTGF-beta. The MLN cell- and rTGF-beta-induced inhibition was reversed by anti-IL-10 mAb significantly in Th1-induced inflammation and only partially in Th2-induced inflammation. rIL-10 reduced Th-induced ear swelling, although higher doses of rIL-10 were required in Th2-induced one. Thus, allergen-specific TGF-beta-producing CD4+ T cells induced in the respiratory tract controlled cutaneous inflammatory responses by Th1 or Th2 cells either directly by TGF-beta or indirectly through IL-10 induction. From a clinical standpoint, these observations might explain the mechanism of spontaneous regression in some patients with atopic dermatitis, which exhibits both Th1- and Th2-mediated skin inflammation in response to airborne protein Ags.

Animals↗

PubMed2001

Leukemia inhibitory factor induces nociceptin mRNA in cultured rat cortical neurons.

The effects of leukemia inhibitory factor (LIF) on the expression of neurotransmitter synthetase and neuropeptide mRNAs in cultured rat cortical neurons were examined by reverse transcription-polymerase chain reaction. Nociceptin mRNA expression was increased by treatment with 20 or 80 ng/ml LIF for 24 h, but choline acetyl transferase, glutamic acid decarboxylase, enkephalin, dynorphin, substance P, somatostatin and galanin mRNA expression were not altered by LIF. These observations indicated a specific effect of LIF on nociceptin gene regulation in cultured cortical neurons.

Aging↗

PubMed2001

Stereochemistry of aldols: configuration and conformation of aldols derived from cycloalkanones and aldehydes.

The structures of cycloalkanone-based threo and erythro aldols were investigated by systematic introduction of stereo-determining factors. The combination of single-crystal X-ray analysis and cryoscopic measurement and solution NMR and IR studies elucidated the detailed geometry of these typical aldols. Currently, X-ray diffraction is the only reliable spectroscopic method to determine the relative configuration of aldols. Empirical NMR analysis can be safely applied in only limited cases. In hydrocarbon solvents, many aldols exist as monomers with an intramolecular OH...O=C hydrogen bond, but some compounds are in an equilibrium with higher aggregates via intermolecular hydrogen bonds. The aldols take various staggered conformers, where the relative stabilities are controlled largely by torsional strain affected by the size and nature of substituents. The intramolecular and intermolecular hydrogen bonds, gauche interactions between the vicinal substituents, and sometimes CH/pi attractions significantly influence the distribution of conformers. The preferred structure in solution often differs greatly from the crystalline-state geometry.

Journal Article↗

PubMed2001

Altered expression of HES-1, BETA2/NeuroD, and PDX-1 is involved in impaired insulin synthesis induced by glucocorticoids in HIT-T15 cells.

Expression of the insulin gene is highly specific to pancreatic beta cells and is upregulated mainly by PDX-1 and BETA2/NeuroD depending on the extracellular glucose concentration. However, its downregulation has not been well studied. Reporter gene analyses using pancreatic HIT-T15 cells revealed that the glucose-dependent insulin promoter activity was blocked by glucocorticoids, dexamethasone (DEX) and hydrocortisone, in a dose-dependent manner. After the addition of DEX (20 nM) to HIT-T15 cells, a decrease of insulin mRNA was observed at 12-24 h, followed by a decline of insulin protein at 48 h. Expressions of PDX-1 and BETA2/NeuroD decreased within 2 h. HES-1, a potent negative regulator of bHLH-type transcription factors, was found to be expressed in HIT-T15 cells, and its expression was increased 6 h after the addition of DEX. Overexpression of HES-1 suppressed the insulin promoter activity in a dose-dependent manner. These results suggest that glucocorticoids impair insulin synthesis in HIT-T15 cells by decreasing PDX-1 and BETA2/NeuroD and that enhancement of HES-1 expression is involved in this regulation.

Animals↗

PubMed2001

Interaction of the SH2 domain of Fyn with a cytoskeletal protein, beta-adducin.

Fyn is a Src family tyrosine kinase expressed abundantly in neurons and believed to have specific functions in the brain. To understand the function of Fyn tyrosine kinase, we attempted to identify Fyn Src homology 2 (SH2) domain-binding proteins from a Nonidet P-40-insoluble fraction of the mouse brain. beta-Adducin, an actin filament-associated cytoskeletal protein, was isolated by two-dimensional gel electrophoresis and identified by tandem mass spectrometry. beta-Adducin was tyrosine phosphorylated by coexpression with wild type but not with a kinase-negative form of Fyn in COS-7 cells. Cell staining analysis showed that coexpression of beta-adducin with Fyn induced translocation of beta-adducin from the cytoplasm to the periphery of the cells where it was colocalized with actin filaments and Fyn. These findings suggest that tyrosine-phosphorylated beta-adducin associates with the SH2 domain of Fyn and colocalizes under plasma membranes.

Amino Acid Sequence↗