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T Nagase

Publications and source records attributed to T Nagase.

At least 163 records · Page 9Linked to original sources
PubMed1995

In vitro airway and tissue response to antigen in sensitized rats. Role of serotonin and leukotriene D4.

We have recently demonstrated that tissue resistance increases during the early response (ER) to antigen challenge in sensitized Brown-Norway rats. The purpose of the present study was to investigate the in vitro airway and tissue responses to antigen and the involvement of the potential mediators serotonin (5-HT) and leukotriene D4 (LTD4). We sensitized Brown-Norway rats with ovalbumin (OA) and subsequently challenged bronchial rings and subpleural parenchymal strips with OA in the organ bath. In selected experiments tissues were incubated with methysergide (a 5-HT receptor antagonist), ketanserin (a 5-HT2 receptor antagonist), MK-571 (a LTD4 receptor antagonist), or MK-886 (5-lipoxygenase inhibitor) prior to challenge. Both bronchial rings and parenchymal strips constricted in response to OA. Methysergide and ketanserin completely inhibited OA-induced constriction of bronchial rings. The effect of MK-571 was not significant, whereas MK-886 partially blocked OA-induced bronchial constriction, suggesting a potential role for LTC4 in antigen-induced airway constriction. In parenchymal strips, methysergide, ketanserin, MK-571, and MK-886 all partially inhibited the OA response, whereas the combinations of methysergide and MK-571 or ketanserin and MK-886 completely ablated the response. These data suggest that both bronchial rings and parenchymal strips constrict after OA challenge but that the relative contributions of 5-HT and LTD4 to the allergic response in central airways and parenchymal tissues differ.

Airway Resistance↗
PubMed1995

Antagonism of ICAM-1 attenuates airway and tissue responses to antigen in sensitized rats.

Airway inflammation is involved in the pathogenesis of bronchial asthma. Intercellular adhesion molecule-1 (ICAM-1) is a ligand for lymphocyte function-associated antigen-1 alpha (LFA-1 alpha) and has been shown to be required for leukocyte migration into inflamed area. The purpose of this report was to investigate the role of ICAM-1/LFA-1 alpha pathway in a rat model of extrinsic asthma using monoclonal antibodies (mAbs). We chose to study ovalbumin (OA)-sensitized Brown-Norway rats, an animal model in which there is a high prevalence of both early (ER) and late responses (LR) after antigen challenge. We measured tracheal and alveolar pressure using alveolar capsules in open-chested, mechanically ventilated animals to calculate resistance of lung (RL), tissue (Rti), and airway (Raw). In the OA group, both ER (RL, Rti, Raw = 263 +/- 16, 235 +/- 10, 309 +/- 38% baseline) and LR (RL, Rti, Raw = 265 +/- 26, 238 +/- 13, 316 +/- 55% baseline) were observed. The administration of mAbs to ICAM-1 and LFA-1 alpha significantly attenuated the ER (RL, Rti, Raw = 146 +/- 9, 141 +/- 11, 156 +/- 8% baseline) and LR (RL, Rti, Raw = 128 +/- 8, 124 +/- 5, 137 +/- 1% baseline), indicating that both airway and lung tissues were involved in this mechanism. The current observations suggest that ICAM-1/LFA-1 alpha pathway is involved in both the early and late responses in a rat model of allergic asthma. The antagonism of ICAM-1 and LFA-1 alpha may provide a potential therapeutic approach to the early and late responses of bronchial asthma.

Airway Resistance↗
PubMed1995

Expression of immunoreactive and bioactive activin A protein in adult murine lung after bleomycin treatment.

Activin A is a homodimeric protein structurally and functionally related to transforming growth factor beta (TGF-beta), and the expression of activin A is modulated by TGF-beta. Here, we demonstrate the expression of activin A in normal and bleomycin (BLM)-treated murine lungs. ICR mice were treated with BLM intraperitoneally for 10 days, whereas saline vehicle was injected into control mice. Intra-alveolar fibrotic changes were observed in the lung tissue obtained from the mice at day 14 after the final BLM administration. Immunohistochemical studies using a polyclonal antibody to activin A revealed the presence of activin A in the bronchiolar epithelium and smooth muscle cells of veins in both control and BLM-treated mice. In the BLM-treated mice at days 7 and 14, the marked infiltration of immunoreactive alveolar macrophages was observed in the area of fibrotic changes. Bioactivity of activin A measured by erythroid differentiation factor assay in the conditioned medium of alveolar macrophages obtained from BLM-treated mice at day 14 was significantly increased. These findings indicate that alveolar macrophages are a potent source of activin A after BLM treatment. The present study demonstrates for the first time the abundant expression of activin A in murine lung tissues after BLM administration, suggesting that activin A may play a role in the pathogenesis of BLM-induced pulmonary fibrosis.

Activins↗
PubMed1995

Effect of cigarette smoking on pulmonary function in each phenotype M of alpha-1-protease inhibitor.

Human alpha-1-protease inhibitor (alpha-1-Pi) has been known to be a highly polymorphic protein. We hypothesized that antiprotease activity of each phenotype M of alpha 1-protease inhibitor (PiM) might be different among smokers and that a variation of decrease in pulmonary function for a given amount of cigarette smoking might be associated with PiM phenotypes. To test this, we investigated the effect of cigarette smoking on pulmonary function in each PiM phenotype. The serum level of alpha 1-Pi was measured by the turbidimetric immunoassay and the distribution of PiM phenotypes was determined using isoelectric focusing technique in 247 healthy subjects and 20 COPD patients. Serum levels of alpha-1-antitrypsin of healthy and COPD subjects were 205.1 +/- 31.1 and 179.2 +/- 44.4 (+/- SD) mg/dL, respectively (p > 0.01). The frequency of each PiM phenotype in healthy subjects was shown as follows: M1, 0.555; M1M2, 0.328; M2, 0.041; M1M3, 0.057; M2M3, 0.016; M3, 0.004. The difference in the distribution of PiM phenotypes between healthy and COPD subjects was not significant. Single- and multiple-regression analyses showed that the ratio of FEV1 to forced vital capacity (FVC), in which FEV1 is expressed as percentage of FVC, the maximum flow rate at 50% of FVC divided by measured body height (V50/Ht), and the maximum flow rate at 25% of FVC divided by body height (V25/Ht) were closely related to age and that V25/Ht also was related to smoking index. However, PiM phenotype was unrelated to those pulmonary function variables. We conclude that PiM phenotype is not a major determinant of difference in magnitude of pulmonary impairments caused by cigarette smoking in each individual.

Adult↗
PubMed1995

Magnetic resonance imaging of multiple brain abscesses of the bilateral basal ganglia.

A 64-year-old woman developed multiple brain abscesses of the basal ganglia associated with Klebsiella pneumoniae septicemia. Magnetic resonance (MR) images showed three different stages of the brain abscesses. The images of early cerebritis of this site mimicked lacunar infarctions or dilated Virchow-Robin spaces. The differentiation of the brain abscess from lacunae and dilated Virchow-Robin spaces is discussed, together with the evolution of the brain abscesses on MR images.

Basal Ganglia↗
PubMed1995

[A case of pulmonary infiltration with eosinophilia (PIE) syndrome associated with syndrome of inappropriate secretion of ADH (SIADH) in the elderly patient].

A 76-year-old woman was admitted to our hospital because of productive cough, fever and anorexia in January 1995. She had suffered from bronchial asthma for 25 years. From 1983, exacerbation of PIE was recorded three times, on which occasions prednisolone and antibiotics were quite effective. On admission, marked leukocytosis (28,000/microliters) and eosinophilia (18,000/microliters) were found. However, plasma IgE level was normal, and specific antigen for eosinophilia was not detected by RAST or the skin allergic reaction test. Chest X-ray film and CT scan revealed extensive bilateral pulmonary infiltration. Increase in eosinophils (33%) was demonstrated in bronchoalveolar lavage. Furthermore, biopsy specimen of the affected lung revealed diffuse infiltration of eosinophils into alveolar septa. On the basis of these findings, the patient was diagnosed as chronic eosinophilic pneumonia (PIE syndrome). Hyponatremia (117 mEq/l) was persistent after the hydration with normal saline. Plasma ADH was not suppressed (2.29 pg/ml) in spite of hypoosmolality of plasma. Laboratory examination showed that renal, adrenal and thyroid function as well as plasma renin activity were normal. Taking these findings together, she was diagnosed as having SIADH. Treatment with prednisolone improved not only the PIE syndrome but also SIADH.

Aged↗
PubMed1995

[Nocturnal pulmonary hypertension in an elderly patient with sleep apnea syndrome].

We report a case of sleep apnea syndrome (SAS) with nocturnal pulmonary hypertension (NPH) in a 71-year-old man suffering from dyspnea during sleep. Severe snoring at night and daytime sleepiness were noticed before admission by his wife. Nocturnal oxygen desaturation (NOD) was documented with a pulse oximeter and severe sleep apnea syndrome was diagnosed on the basis of results of respiratory inductive plethysmography, an apnea index (AI) > 20, minimum SpO2 56%. NPH was diagnosed by Swan-Ganz catheter. The levels of NPH were severe. Elevation of systolic pulmonary arterial pressure (PAP) above 40 mmHg was observed 137 episodes at night. Both NPH and NOD were improved by 1 L/min of nasal oxygen therapy. A number of episodes of systolic PAP above 40 mmHg with oxygen therapy was 55 episodes. Peak mean PAP was 36 mmHg in room air vs 33 mmHg in oxygen therapy. Minimum SpO2 with oxygen therapy was improved to 69%. Total time of SpO2 < 90% at night was 153 minutes in room air vs 37 minutes in oxygen therapy. In this case, NPH and NOD due to severe SAS were remarkably improved by oxygen therapy.

Aged↗
PubMed1995

A visual telemedicine system: the integration of ordinary TV and HDTV still image transmission.

This paper describes a project to develop and test a new telemedicine system using image transmission. The system was implemented at Aomori prefecture, the northernmost prefecture of Japan, to provide medical consultation to remote hospitals from a medical center located in Aomori city, capital of the prefecture. The characteristics of the system are the combination of an HDTV still image transmission system and an ordinary tele-conference system using 65 kilobit telephone line i.e., an ordinary telephone line available in almost any part of Japan. We also developed a disk storage system that stores transmitted images automatically without human intervention. The system was assessed in real clinical settings and has proved to be effective in various areas of medical consultation, including radiology, pathology, dermatology, etc. We hope that this system becomes a standard telemedicine system in the future.

Computer Peripherals↗
PubMed1994

Biochemical and pharmacological profile of a potent and selective endothelin B-receptor antagonist, BQ-788.

We describe the characteristics of a potent and selective endothelin (ET) B-receptor antagonist, BQ-788 [N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D -1- methoxycarbonyltryptophanyl-D-norleucine]. In vitro, this compound potently and competitively inhibits 125I-labeled endothelin 1 (ET-1) binding to ETB receptors on human Girardi heart cells (IC50, 1.2 nM) but only poorly inhibits the binding to ETA receptors on human neuroblastoma cell line SK-N-MC cells (IC50, 1300 nM). In isolated rabbit pulmonary arteries, BQ-788 shows no agonist activity up to 10 microM and competitively antagonizes the vasoconstriction induced by an ETB-selective agonist, BQ-3020 (pA2, 8.4). In rat, an ETA-selective antagonist, BQ-123 (1 mg/kg, i.v.), does not affect transient depressor response to ET-1 (0.3 nmol/kg, i.v.) but potently inhibits following sustained pressor response; vice versa, BQ-788 (1 mg/kg, i.v.) abolishes the depressor response, resulting in a rapid onset of apparently enhanced pressor response. Thus, being a potent and selective ETB receptor antagonist, BQ-788 may be considered as a powerful tool for investigating the role of ET in physiological and pathological processes.

Amino Acid Sequence↗
PubMed1994

Interleukin-6 in transcatheter arterial embolization for patients with hepatocellular carcinoma. Effects of serine protease inhibitor.

BACKGROUND: Modulation of serum levels of circulating cytokines and inflammatory responses with a serine protease inhibitor was studied in 34 patients with hepatocellular carcinoma (HCC) after transcatheter arterial embolization (TAE). METHODS: The 34 patients were randomly divided into two groups: 17 patients received 500 mg gabexate mesilate, a serine protease inhibitor, intravenously twice a day for 5 days after TAE, and the remaining 17 patients did not receive the drug. RESULTS: In the patients not given the drug, circulating interleukin-6 (IL-6) markedly increased 1 day after TAE, reached a peak (approximately 8 times the pretreatment value) after 4 days, and remained elevated 7 days after TAE. In comparison, in the patients given the drug, circulating IL-6 was at a significantly lower level at 4 and 7 days after TAE (P < 0.05, respectively). Both groups did not show significant change in circulating interleukin-1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF alpha) during the week after TAE. The drug also showed a tendency to keep patient temperature below 38 degrees C, and the elevation of serum C-reactive protein (CRP) concentration to less than 1 mg/dl after TAE (P < 0.05, respectively). CONCLUSIONS: The serum level of circulating IL-6 can be modulated by serine protease inhibitor, and this may contribute to suppressing inflammatory responses, such as fever and acute-phase protein synthesis, in the liver after TAE.

Aged↗
PubMed1994

Modulation of the mevalonate pathway and cell growth by pravastatin and d-limonene in a human hepatoma cell line (Hep G2).

Modulation of cell growth by a combination of pravastatin [a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor] and d-limonene (an inhibitor of protein isoprenylation) was studied using Hep G2, a human hepatoma-derived cell line. Pravastatin, at 0.1 mM, produced 85% inhibition of cholesterol biosynthesis in Hep G2 cells. The combination of 0.1 mM pravastatin and 1.0 mM d-limonene had no further effect on the reduction seen with pravastatin alone. Addition of 0.1 mM pravastatin or 1.0 mM d-limonene did not significantly suppress DNA synthesis by the cells, whereas the combination suppressed it to 50% of the control level. Production of m-p21ras was markedly decreased to 35% of the control level by the combination of these two inhibitors. Both the reduction by pravastatin of farnesylpyrophosphate as substrate for protein:farnesyl transferase and inhibition of protein farnesylation by d-limonene seem to be responsible for the profound suppression of m-p21ras formation in the cells. However, dolichol synthesis was not suppressed by the combination of these inhibitors. In human fibroblasts, the combination suppressed m-p21ras production but not DNA synthesis. These findings suggest that the combination of pravastatin and d-limonene acts on cancer cell growth through inhibition of the post-translational processing of cellular proteins including p21ras, rather than through the suppression of cholesterol and dolichol biosynthesis. Thus, the combination of an HMG-CoA reductase inhibitor and an inhibitor of protein isoprenylation offers potential as a new approach for cancer therapy.

Antineoplastic Agents↗
PubMed1994

Prediction of the coding sequences of unidentified human genes. I. The coding sequences of 40 new genes (KIAA0001-KIAA0040) deduced by analysis of randomly sampled cDNA clones from human immature myeloid cell line KG-1.

We established a protocol for the prediction of the coding sequences of unidentified human genes based on the double selection and sequence analysis of cDNA clones with inserts carrying unreported 5'-terminal sequences and with insert sizes corresponding to nearly full-length transcripts. By applying the protocol, cDNA clones with inserts longer than 2 kb were isolated from a cDNA library of human immature myeloid cell line KG-1, and the coding sequences of 40 new genes were predicted. A computer search of the sequences indicated that 20 genes contained sequences similar to known genes in the GenBank/EMBL databases. The sequences of the remaining 20 genes were entirely new, and characteristic protein motifs or domains were identified in 32 genes. Other sequence features noted were that the coding sequences of 23 genes were followed by relatively long stretches of 3'-untranslated sequences and that 5 genes contained repetitive sequences in their 3'-untranslated regions. The chromosomal location of these genes has been determined. By increasing the scale of the above analysis, the coding sequences of many unidentified genes can be predicted.

Base Sequence↗
PubMed1994

Prediction of the coding sequences of unidentified human genes. II. The coding sequences of 40 new genes (KIAA0041-KIAA0080) deduced by analysis of cDNA clones from human cell line KG-1.

By applying the protocol previously established, we isolated and sequenced full-length cDNA clones longer than 2 kb from cDNA library of human immature myeloid cell line KG-1, and the coding sequences of 40 new genes were predicted. A computer search of the sequences indicated that 29 genes contained sequences with similarities to reported genes in the GenBank/EMBL databases. Significant transmembrane domains were identified in 9 genes, 5 of which harbored multiple hydrophobic regions. Protein motifs that matched those in the PROSITE motif database were identified in 13 genes. In terms of sequence similarities and protein motifs, 5 genes were related to transcriptional factors. Repetitive sequences were found in the 3'-untranslated region of 8 genes. Northern hybridization demonstrated that the expression of 9 genes was tissue-specific, while the remaining 31 genes were expressed ubiquitously. It was also noted that 17 genes yielded different sizes of bands possibly due to either alternative splicing or alternative initiation. The chromosomal location of these genes has been determined.

Amino Acid Sequence↗
PubMed1994

Adenovirus pulmonary infections identified by PCR and in situ hybridisation in bone marrow transplant recipients.

AIMS: To investigate adenovirus pulmonary infections in bone marrow transplant (BMT) recipients. METHODS: Formalin fixed, paraffin wax embedded lung tissue was examined from 13 necropsy cases after BMT using PCR and in situ hybridisation to detect adenovirus DNA. The E1A region of the adenoviral genome was targeted for PCR. In situ hybridisation was performed only in the PCR positive cases. RESULTS: Of the 13 lung specimens analysed, nine cases were negative for adenoviral nucleic acid. Four (30%) PCR and two (15%) in situ hybridisation positive cases were found. In some of the patients there were clinical and pathological indications that some diseases might be associated with adenovirus infection--haemorrhagic cystitis (three cases); necrotising pneumonia (one case). In necrotising pneumonia in which no pathogenic agents had been shown by conventional histological study, the in situ hybridisation technique showed positive staining for adenovirus. In a patient who died of renal failure caused by adenovirus nephritis, both PCR and in situ hybridisation were positive in the lung as well as in the kidney, although no histological change was found. Two PCR positive cases lacked positive sites for adenovirus by in situ hybridisation. CONCLUSIONS: The combination of PCR and in situ hybridisation could be useful for diagnosing adenovirus infection of the lung in BMT recipients. These results provide a basis for exploring further the clinical use of PCR and in situ hybridisation to diagnose adenovirus infection.

Adenovirus Infections, Human↗
PubMed1994

Airway and tissue behavior during induced constriction in rats: intravenous vs. aerosol administration.

The distribution of contractile agonist during intravenous (i.v.) or aerosol (AR) administration is likely to be different. We questioned whether the different pattern of distribution would result in different effects on lung tissue response. We measured tracheal and alveolar pressure in open-chest mechanically ventilated [frequency 1 Hz, tidal volume 8 ml/kg, positive end-expiratory pressure (PEEP) 3 cmH2O] rats under control conditions and after i.v. or AR administration of saline or methacholine (MCh; i.v., 50 micrograms.kg-1.min-1; AR, 256 mg/ml). We calculated lung elastance and resistances of lung, tissue, and airway by fitting the equation of motion to changes in tracheal and alveolar pressure. Lungs were then frozen in situ with liquid nitrogen (PEEP=3 cmH2O) and processed via freeze substitution. Airway constriction was assessed by measuring the ratio of airway lumen to ideally relaxed area. Tissue distortion was assessed by measuring mean linear intercept between alveolar walls (Lm), atelectasis index (ATI) derived by calculating ratio of tissue to air space, and SD of Lm and ATI. I.v. and AR MCh increased lung resistance to a similar degree. However, changes in tissue resistance and lung elastance after AR MCh were significantly greater than those after i.v. MCh, whereas the change in airway resistance was significantly less. After i.v. MCh, airway constriction was prominent and evenly distributed. After AR MCh, airway constriction was less prominent and decreased as airway size decreased. Tissue distortion, i.e., SD of Lm and ATI, was significantly greater after AR than i.v. MCh.(ABSTRACT TRUNCATED AT 250 WORDS)

Aerosols↗
PubMed1994

Mechanical interdependence in relation to age: effects of lung volume on airway resistance in rats.

Elastic recoil has been reported to decrease with increasing age in human subjects. In the current study, we hypothesized that aging influences mechanical interdependence, which affects the magnitude of agonist-induced airway constriction. To examine this hypothesis, we compared the effects of changing lung volume on airway resistance (Raw) under baseline conditions and during methacholine-induced constriction in adult (14 mo old, 624 +/- 14 g; n = 11) and aged (29 mo old, 629 +/- 9 g; n = 11) Sprague-Dawley rats. With use of alveolar capsules, Raw was directly measured under baseline conditions at different levels of end-expiratory transpulmonary pressure (PL; 3-11 cmH2O). Then aerosolized methacholine was delivered (125 mg/ml), and measurements were performed at different levels of PL (3 and 11 cmH2O). From measured tracheal flow and tracheal and alveolar pressures in open-chest animals during mechanical ventilation (6 ml/kg tidal volume, 1 Hz frequency), we calculated dynamic lung elastance and resistance of lung, tissue, and airway. In the baseline conditions, we found that increasing lung volume decreased Raw similarly in both groups but that lung elastance was reduced in the aged group at PL > or = 7 cmH2O. The shape constant obtained from the pressure-volume curve in the aged rats was significantly greater than that in the adult rats. During induced constriction, higher lung volume significantly lowered Raw in the adult group, whereas Raw was not significantly reduced by increasing PL in the aged group. These observations suggest that increasing age may affect the mechanical properties of the airway and/or airway-parenchymal interdependence.

Aging↗