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Biomedical subjects

N Kurihara

Publications and source records attributed to N Kurihara.

At least 55 records · Page 3Linked to original sources
PubMed1998

Churg-Strauss syndrome diagnosed and followed with gastrointestinal fiberscopic studies and electroneuromyography.

Churg-Strauss syndrome (CSS) is a disorder characterized by hypereosinophilia and systematic vasculitis occurring in individuals with bronchial asthma. We present a case of 24-year-old woman with CSS diagnosed by and followed with gastrointestinal fiberscopic examination and electroneuromyography. The duodenal biopsy showed granulomatous angiitis with eosinophilic infiltration, and the electroneuromyography showed peripheral nerve dysfunction. After steroid treatment, the duodenal erosion and ulcer were almost completely resolved. There was no improvement in electroneuromyography, but the patient was able to walk independently after intensive rehabilitative training.

Adult↗
PubMed1998

Clinical implication of protein levels of IL-5 in induced sputum in asthmatic patients.

To determine whether protein levels of interleukin-5 (IL-5) in induced sputum reflect the degree of eosinophilic inflammation, we evaluated the role of IL-5 on clinical characteristics in stable asthmatic patients. IL-5 level, differential eosinophil count, and level of eosinophil cationic protein (ECP) in induced sputum were all significantly higher for asthmatics than for normal controls. Both eosinophil counts and ECP levels in induced sputum were inversely correlated with the degree of airflow limitation (FEV1/FVC). In addition, patients with measurable IL-5 in sputum had significantly more eosinophils, higher levels of ECP in sputum, and lower FEV1 (percent predicted) than did patients with levels of IL-5 beneath the limit of detection. However, we found no significant difference in IL-5 levels between atopic and nonatopic asthmatics. IL-5 level in induced sputum is a good indicator of eosinophilic inflammation in atopic and nonatopic asthmatic patients.

Adult↗
PubMed1998

[Efficacy of combination of ondansetron injection and tablet in CAF-induced emesis in breast cancer patients].

Efficacy of combination of ondansetron injection and tablet on CAF (cyclophosphamide, adriamycin, 5-fluorouracil) induced emesis were investigated in 10 breast cancer patients (33 courses). Complete suppression rate of nausea or vomiting were approximately 75%, approximately 90% respectively for every treatment day. According to judgement criteria, antiemetic rate of approximately 100% was achieved during the study period. As to food intake of each treatment day, in approximately 70% of treatment courses was assessed as '(patient was) able to eat most of the meal'. Trend in emetic episodes and food intake in each patient receiving several courses of CAF therapy were evaluated. As a result, those patients experiencing nausea or vomiting or had effect on their food intake, were found to be in the similar condition in the following course (s) of CAF. No adverse drug reaction nor clinical laboratory test abnormalities due to ondansetron was observed. In this investigation, combination of ondansetron injection and tablet was shown to sufficiently suppress CAF-induced nausea and vomiting, and their efficacy was confirmed. Still, the study suggested that number of emetic episodes or degree of anorexia differs according to each individual. Therefore we regard additional administration of ondansetron or concomitant use of steroids should be considered when necessary.

Administration, Oral↗
PubMed1998

Functional MR imaging of cortical activation of the cerebral hemispheres during motor tasks.

PURPOSE: We used functional MR imaging to evaluate cortical activation in the precentral, central, and postcentral regions of the contralateral and ipsilateral cerebral hemispheres during left- and right-handed motor tasks. METHODS: Ten healthy right-handed volunteers were studied with echo-planner MR imaging (1.5 T) while performing alternating finger apposition tasks with both hands. During the hand tasks, the areas of activated pixels were compared between subregions (precentral, central, and postcentral) of the contralateral and ipsilateral sensorimotor cortex. RESULTS: The activated area of the contralateral sensorimotor cortex was significantly larger than that of the ipsilateral cortex during tasks with either hand, whereas the ipsilateral activated area was significantly larger during the left-handed task than during the right-handed task. Ipsilateral activation was greatest in the precentral region, less in the central region, and least prominent in the postcentral region. CONCLUSIONS: Our results confirmed those of previous investigators that ipsilateral activation is more pronounced during left-sided movements than during right-sided movements. The variation in activation of the precentral, central, and postcentral subregions suggests different roles of the ipsilateral and contralateral hemispheres during motor tasks.

Adult↗
PubMed1998

Macrophage-stimulating protein (MSP) and its receptor, RON, stimulate human osteoclast activity but not proliferation: effect of MSP distinct from that of hepatocyte growth factor.

Stem cell-derived tyrosine kinase (STK) is a member of the hepatocyte growth factor (HGF) receptor family. The ligand for STK, macrophage-stimulating protein (MSP), is a serum protein activated by members of the coagulation cascade. The RON gene is a human homolog of the murine STK. In this study we examined the role of MSP-RON in the signal pathway of human osteoclasts. Using anti-RON antibody, we detected RON expressed in multinucleated osteoclast-like cells (OCLs) formed in cultures of human bone marrow cells. To determine bone resorption, we placed OCLs on thin films of ceramic calcium phosphate formed on quartz plate-coated slides (Millenium Biologix) and measured pit formation. MSP stimulated pit formation by OCLs in a dose-dependent manner. MSP (50 ng/mL) caused a fourfold increase in pit area compared with the control. Furthermore, we examined the effects of MSP and HGF on OCL formation by purified populations of hematopoietic progenitors. OCLs were phenotypically identified by their cross-reactivity with 23c6, a monoclonal antibody that preferentially binds to osteoclasts. HGF (50 ng/mL) stimulated the differentiation of progenitors to 23c6-positive OCLs but did not enhance bone absorption. In contrast, MSP did not affect proliferation of osteoclast precursors but stimulated bone resorption by OCLs. We conclude that the MSP signal transduction pathway plays a role in bone resorption that is distinct from that of HGF.

Bone Marrow Cells↗
PubMed1998

Characteristics of Helicobacter pylori strains isolated from patients with different gastric diseases.

The pathogenesis of chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis is considered to be related to infection by Helicobacter pylori. The purpose of this study was to investigate the characteristics of H. pylori strains isolated from patients with various gastric diseases. Fifty strains of H. pylori were clinically isolated at Keio University Hospital and were assessed for (i) vacuolating cytotoxin (VT) production, by cytotoxic assay using rabbit kidney (RK) 13 cells; (ii) the expression of cytotoxin associated gene (cagA), by polymerase chain reaction; and (iii) motility on a semi-solid plate. Positivity for VT production by H. pylori strains isolated from patients with chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis, was 100%, 89%, 92%, 100%, and 60%, respectively. There was no significant difference in the incidence of positivity for cagA among the strains isolated from different gastric diseases. Swarming distances, which indicate motility of H. pylori strains, were 12.7, 13.2, 12.8, 16.6 and 9.2mm in strains from chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis, respectively, with H. pylori isolated from remnant gastritis showing significantly less motility than H. pylori isolates from other diseases. There were no significant differences in VT production and cagA positivity among the H. pylori strains.

Animals↗
PubMed1997

Correlation of lesions in the hippocampal region noted on MR images with clinical features.

The purpose of our work was to compare the MR imaging findings of obvious hippocampal and/or juxtahippocampal lesions with corresponding clinical features. Magnetic resonance images of 63 patients with obvious lesions in the hippocampal and/or juxtahippocampal regions were reviewed and their findings were correlated with patients' clinical characteristics. Based on the MR and clinical findings, the patients were divided into four groups: (a) 26 patients with space occupying lesions or suspected vascular malformation frequently causing symptomatic temporal epilepsy; (b) 14 with hippocampal infarcts, which when left-sided or bilateral caused amnesia; (c) 11 with encephalitis and 5 with old temporal contusion usually accompanied by both amnesia and epilepsy; and (d) 7 with temporal atrophy and progressive dementia of subacute onset. Magnetic resonance imaging allows precise localization and evaluation of the clinical correlates of hippocampal and juxtahippocampal lesions, which frequently caused symptomatic temporal epilepsy and/or amnesic syndrome.

Adolescent↗
PubMed1997

CT and MR imaging of craniopharyngioma.

We reviewed imaging findings of CT and MR imaging in 20 cases of surgically confirmed craniopharyngioma in an attempt to determine their relation to patterns of tumor extent. The relationship between these patterns and the frequency of preoperative CT diagnosis and MR imaging diagnosis according to the surgical diagnosis were determined. The CT technique was superior to MR imaging in the detection of calcification. The MR imaging technique was superior to CT for determining tumor extent and provided valuable information about the relationships of the tumor to surrounding structures. Thus, CT and MR imaging have complementary roles in the diagnosis of craniopharyngiomas. In cases of possible craniopharyngioma, noncontrast sagittal T1-weighted images may enable the identification of the normal pituitary, possibly leading to the correct diagnosis.

Adolescent↗
PubMed1997

Relationship between isocapnic buffering and maximal aerobic capacity in athletes.

This study was performed to clarify the relationship between isocapnic buffering and maximal aerobic capacity (VO2max) in athletes. A group of 15 trained athletes aged 21.1 (SD 2.6) years was studied. Incremental treadmill exercise was performed using a modified version of Bruce's protocol for determination of the anaerobic threshold (AT) and the respiratory compensation point (RC). Ventilatory and gas exchange responses were measured with an aeromonitor and expressed per unit of body mass. Heart rate and ratings of perceived exertion were recorded continuously during exercise. The mean VO2max, oxygen uptake (VO2) at AT and RC were 58.2 (SD 5.8) ml x kg(-1) x min(-1), 28.0 (SD 3.3) ml x kg(-1) x min(-1) and 52.4 (SD 6.7) ml x kg(-1) x min(-1), respectively. The mean values of AT and RC, expressed as percentages of VO2max, were 48.3 (SD 4.2)% and 90.0 (SD 5.2)%, respectively. The mean range of isocapnic buffering defined as VO2 between AT and RC was 24.4 (SD 4.5) ml x kg(-1) x min(-1), and the mean range of hypocapnic hyperventilation (HHV) defined as VO2 between RC and the end of exercise was 5.8 (SD 3.0) ml x kg(-1) x min(-1). The VO2max per unit mass was significantly correlated with AT (r = 0.683, P < 0.01). In addition, VO2max/mass was closely correlated with both the range of isocapnic buffering (r = 0.803, P < 0.001) and RC (r = 0.878, P < 0.001). However, no correlation was found between VO2max per unit mass and the range of HHV (r = 0.011, NS.). These findings would suggest that the prominence of isocapnic buffering, in addition to the anaerobic threshold, may have been related to VO2max of the athletes. The precise mechanisms underlying this proposed relationship remain to be elucidated.

Adult↗
PubMed1997

Molting hormonal and larvicidal activities of aliphatic acyl analogs of dibenzoylhydrazine insecticides.

Dibenzoylhydrazines are the nonsteroidal ecdysone agonists. Using comparative molecular field analysis, we previously found that the alkyl side chain of 20-hydroxyecdysone (20E) is three-dimensionally superposable with one of their two aryl moieties. To identify the aryl moiety that is better superposable on the alkyl chain, we synthesized compounds in which one of the two aryl groups of tebufenozide (N-t-butyl-N-3,5-dimethylbenzoyl-N'-4-ethylbenzoylhydrazine) is replaced by alkyl groups such as C4H9, C5H11, and C6H13. The molting hormonal activity of these compounds was measured using cultured integuments prepared from rice stem borers, Chilo suppressalis Walker, in terms of stimulation of incorporation of N-acetyl-[14C]glucosamine. N-t-Butyl-N-3,5-dimethylbenzoyl-N'-acylhydrazines with a hexanoyl or heptanoyl group were about 20-fold higher than that of 20E, whereas N-acyl-N-t-butyl-N'-4-ethylbenzoylhydrazines with a hexanoyl or heptanoyl group were much weaker than 20E. Their larvicidal activity was also measured against rice stem borers. The former series of compounds were much more active than the other series as well as 20E. Thus, the benzoyl moiety of dibenzoylhydrazines, which is bound to the secondary nitrogen atom (-NH-), is replaceable by aliphatic acyl groups without greatly affecting the biological activities.

Acylation↗
PubMed1997

Supratentorial primary intra-axial tumors in children. MR and CT evaluation.

PURPOSE: To evaluate the MR and CT features of pediatric supratentorial intra-axial tumors with respect to differential diagnosis and the role of each investigation modality. MATERIAL AND METHODS: MR and CT findings in 40 children with 12 types of pathologically proven histological tumors were reviewed. RESULTS: The location of tumors might be one clue to differential diagnosis. In our material, cysts (60%), calcifications (45%), and intratumoral hemorrhages (27%) were found in the tumors. Characteristic features noted in some lesions included: peritumoral hemosiderin deposition in cavernous angiomas; intratumoral flow void in a choroid plexus carcinoma and in glioblastomas; and hemicerebral atrophy in germinomas. A comparison between malignant and benign tumors showed perifocal edema and a mass effect to be significantly more common in malignant lesions. Homogeneous enhancement suggested a benign tumor and an inhomogeneous pattern represented malignancy, while the lack of obvious enhancement did not always suggest benignity. Intratumoral calcium deposition was a not uncommon finding in malignant tumors. CONCLUSION: In most cases, the exact diagnosis should be made by histological examination but it is important for treatment planning that the appropriate depiction of tumor extension and tissue characterization be made by MR and CT.

Adolescent↗
PubMed1997

Heat-shock protein 60 homologue of Helicobacter pylori is associated with adhesion of H. pylori to human gastric epithelial cells.

A previous study reported a relationship between the expression of heat-shock protein 60 (HSP60) by Helicobacter pylori and its adhesion to human gastric carcinoma (MKN45) cells. To examine whether the HSP60 homologue of H. pylori is associated with the adhesion of H. pylori to human gastric epithelial cells, an inhibition assay of adhesion of H. pylori to MKN45 cells was performed by flow cytometric analysis with monoclonal antibody (MAb) designated as H20 recognising HSP60 of H. pylori. The rate of adhesion of H. pylori pretreated with MAbH20 to MKN45 cells was lower than that of untreated H. pylori. Primary human gastric epithelial cells from a patient with gastric cancer were also prepared for comparison in the inhibition assay with MAbH20. H. pylori adhered to the primary human gastric epithelial cells, and this adhesion was significantly inhibited by MAbH20. These results suggest that the H. pylori HSP60 homologue recognised by MAbH20 might be associated with the adhesion of H. pylori to primary human gastric epithelial cells as well as to cultured gastric cancer cells.

Adhesins, Bacterial↗
PubMed1997

Effect of exercise training and detraining on gas exchange kinetics in patients with chronic obstructive pulmonary disease.

Symptom-limited incremental exercise tests are used to estimate the training effect on patients with chronic obstructive pulmonary disease (COPD). However, there is a need for objective parameters for measurement on submaximal exercise testing. The purpose of this study was to assess the usefulness of measurement of oxygen uptake (VO2) kinetics during a constant work rate exercise test of patients with COPD after exercise training. Eleven patients with COPD performed exercise tests before and after cycle ergometer training on 3 days per week for 8 weeks; they then went without training for 5 months and performed the same tests. They performed an incremental exercise test to symptom-limited maximum and a constant work rate exercise test for 6 min on a cycle ergometer. The time constant of VO2 during the onset of constant work rate exercise was significantly decreased (from 63.5 +/- 7.8 s to 53.2 +/- 8.0 s) after exercise training (P = 0.021), but was significantly increased (to 73.4 +/- 14.9 s) after 5 months without training (P = 0.001). The oxygen pulse at steady state during constant work rate exercise testing was significantly increased after exercise training but decreased 5 months later. The change in blood lactate from rest to steady state during constant work rate exercise was significantly decreased after exercise training, but increased 5 months later. Measurement of the time constant of VO2 and oxygen pulse during constant work rate exercise are useful for the objective evaluation of the training effect of patients with COPD.

Aged↗
PubMed1997

Adenosine modulates endothelin-induced bronchoconstriction in guinea pig airway.

The present study was designed to determine whether endogenous and exogenous adenosine modulates endothelin (ET)-induced bronchoconstriction. Exogenous adenosine enhances ET-induced bronchoconstriction. Following pretreatment with adenosine deaminase and theophylline to eliminate or antagonize endogenous adenosine, ET-1-induced bronchoconstriction was significantly attenuated, but not that of ET-3. In conclusion, this is the first report of an enhancement of ET-induced bronchoconstriction of guinea pig airways by endogenous and exogenous adenosine. Our findings may be useful in designing specific adenosine receptor antagonists as therapeutic agents in the management of bronchial asthma.

Acetylcholine↗
PubMed1997

Synergistic effect of nitric oxide and vasoactive intestinal peptide on bronchoprotection against histamine in anesthetized guinea pigs.

Vasoactive intestinal peptide (VIP) and nitric oxide (NO) are considered to be nonadrenergic, noncholinergic (NANC) inhibitory neurostransmitters in the airways. It seems likely that these neurotransmitters may be coreleased and act as functional antagonists against bronchoconstrictor stimuli. In the present study, we examined the synergistic effect of NO and VIP on bronchoprotection against histamine in anesthetized guinea pigs. The NO donor, S-nitroso-N-acetylpenicillamine (SNAP) significantly inhibited histamine-induced bronchoconstriction in a dose-dependent manner. VIP also inhibited histamine-induced bronchoconstriction in a dose-dependent manner, but this bronchoprotective effect was short-lived. Additionally, VIP (10(-9) M) had no significant bronchoprotective effect, but a subthreshold dose of SNAP (10(-7) M) significantly potentiated VIP (10(-9) M)-induced bronchoprotection against histamine. Moreover, SNAP (10(-7) M) significantly enhanced VIP (10(-7) M)-induced bronchoprotection for a longer period of time. On the other hand, VIP (10(-9) M) also significantly potentiated SNAP-induced bronchoprotection against histamine. In conclusion, combination therapy with NO donor and VIP receptor agonist may have important advantages in the treatment of bronchial asthma, and both NO and VIP may contribute in complementary fashion to the NANC-induced relaxant response in guinea pig airways.

Anesthesia↗
PubMed1997

Research on the estimate of safety and toxicity of p-nitrophenol sodium with a physiologically based pharmacokinetics model.

The safety and toxicity of chemicals given first to animals and finally to humans are generally estimated with a method of safe coefficient, which is scientifically a way lack of grounds. To make a change of the old method, we designed a Physiologically-Based Pharmacokinetics Model for the estimate of safety and toxicity of chemicals. As an example, p-nitrophenol sodium (PNP-Na) is used in the research work. Studies of the PNP-Na pharmacokinetics in bodies of rat as well as humans are made, and possibilities of making use of the Model in the estimate of safety and toxicity of chemicals are discussed.

Animals↗
PubMed1997

[Relationship between exercise-induced hypoxemia and long-term survival in patients with chronic obstructive pulmonary disease].

In patients with chronic obstructive pulmonary disease (COPD), exercise-induced hypoxemia (EIH) is an important limiting factor of exercise performance, but there are very few reports of the prognostic value of EIH. We therefore examined whether EIH is related to long-term outcome in patients with COPD. We gathered data on survival of 77 patients with COPD who had undergone three-minute incremental treadmill exercise tests between 1979 and 1988. A plastic catheter was placed percutaneously into a brachial artery to measure arterial blood gases at each stage of exercise. Expired gas was analyzed continuously during exercise with a Respiromonitor RM-300 (Minato Medical Science). As an index of the severity of EIH we used the delta PaO2/delta VO2 (mmHg/L/min), PaO2-slope. Patients were assigned to two groups according to PaO2-slope, and actuarial survival curves were plotted for the two groups. The survival data were analyzed by generalized Wilcoxon analysis. Survival was significantly better in the group with low PaO2-slopes (< 20 mmHg/L/min) than in the group with high PaO2-slopes (> or = 20 mmHg/ L/min) (p = 0.0031). Also, among the patients in whom PaO2 during exercise was less than 60 mmHg, there was a significant difference in survival between those who received home oxygen therapy and those who did not. We conclude that the degree of EIH can be used to predict survival in patients with COPD, and that the degree of EIH should be considered when prescribing continuous home oxygen therapy for these patients.

Aged↗