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T Kamei

Publications and source records attributed to T Kamei.

At least 55 records · Page 3Linked to original sources
PubMed2000

Studies on antihypertensive agents with antithrombotic activity. 2. Syntheses and pharmacological evaluation of pyrrolo[2,3-c]azepine derivatives.

As an extension of our previous investigation, a series of 7-aminoalkylpyrrolo[2,3-c]azepine derivatives was synthesized and evaluated as alpha1-adrenergic- and serotonin 2 (5-HT2)-receptor antagonists, with the aim of finding a novel potent antihypertensive agent with both activities. Among the compounds obtained in this study, (E)-1-ethyl-7-[3-[4-(4-fluorophenyl)piperazin-1-yl]propyl]-4-hy droxyimino-1,4,5,6,7,8-hexahydropyrrolo[2,3-c]azepin-8-on e (16d) displayed potent alpha1-adrenoceptor blocking activity (pA2=7.83+/-0.20) and 5-HT2-receptor blocking activity (pA2=9.47+/-0.17) in isolated guinea pig arteries. At 3 mg/kg oral administration, compound 16d exhibited antihypertensive activity more potent than that of doxazosin in deoxycorticosterone acetate (DOCA)-salt hypertensive dogs. Furthermore, this compound reduced the rate of mouse acute pulmonary thromboembolytic death induced by collagen and serotonin at oral doses of 0.3 mg/kg or more, and its effect lasted for at least 6 h at 3 mg/kg.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed2000

Synthesis and serotonin 2 (5-HT2) receptor antagonist activity of 5-aminoalkyl-substituted pyrrolo[3,2-c]azepines and related compounds.

A series of 5-aminoalkylpyrrolo[3,2-c]azepine derivatives was synthesized and their serotonin 2 (5-HT2) receptor antagonist and antiplatelet aggregation activities were evaluated. 5-HT2 receptor antagonist activity was largely determined by the nature of the substituent at the 8-position as well as the aminoalkyl group at the 5-position of the pyrrolo[3,2-c]azepine ring. Compound 18a, 5-[3-[4-(4-fluorophenyl)piperazin-1-yl]propyl]-8-hydroxy-1-methyl- 1,4,5,6,7,8-hexahydropyrrolo[3,2-c]azepin-4-one, was recognized as having potent 5-HT2 receptor antagonist activity with weak alpha1 adrenoceptor blocking activity and no significant D2 receptor binding affinity, while the corresponding isomeric pyrrolo[3,4-c]azepine derivative (22) displayed only weak 5-HT2 receptor antagonist activity. After racemic 18a was resolved directly via diastereomeric salt formation, each enantiomer was evaluated precisely. The 5-HT2 receptor antagonist activity of 18a was found to reside primarily in (-)-18a (which was about 14-fold more potent than (+)-18a in isolated guinea pig arteries). Consequently, (S)-(-)-18a (SUN C5174) displayed the overall best profile with potent 5-HT2 receptor antagonist activity (pA2=8.98+/-0.06) and high selectivity versus other receptors. SUN C5174 showed a marked inhibitory effect on the platelet aggregation induced by serotonin in combination with collagen and adenosine diphosphate (ADP) in canine or human platelet-rich plasma (IC50=6.5 to 16 nM). Moreover, this compound significantly inhibited the mortality rate in mouse acute pulmonary thromboembolytic death induced by collagen and serotonin at oral doses of 0.3 mg/kg or higher. SUN C5174 is currently undergoing clinical evaluation.

Adrenergic alpha-2 Receptor Antagonists↗
PubMed2000

Clinical experiences of stenting in patients with esophago-bronchial fistula: report of four cases.

The esophagorespiratory fistula is difficult to treat, and the patients' quality of life is generally poor due to suffering from dysphagia and dyspnea. We performed stent therapy in four cases of the esophagorespiratory fistula associated with esophageal cancer. Three of four patients showed improved symptoms, enabling oral liquid or food intake, although one died of dyspnea despite the therapy. The findings suggest that stent therapy is an effective method to close the esophagorespiratory fistula and to improve the patients' quality of life, although it is temporary and not a radical treatment.

Aged↗
PubMed2000

Pulmonary lymphangiomyomatosis (LAM) developing chylothorax.

We describe a case of pulmonary lymphangiomyomatosis (LAM) with chylothorax that developed in a 46-year-old Japanese woman. This patient exhibited clinical symptoms of dyspnea and chest X-ray showed right pleural effusion. Thoracocentesis demonstrated chylous effusion. Chest computed tomography (CT) scan revealed multiple cystic lesions. Subsequent thoracoscopy revealed the chylorrhea from swelled vessels on the diaphragm. The clinical diagnosis, based on histological examinations with biopsy specimens obtained by thoracoscopy, was pulmonary LAM. Although the hormone therapy was not effective, chylous effusion was improved by the pleurodesis. Pulmonary LAM developing chylothorax is rare in Japan.

Chylothorax↗
PubMed2000

Churg-Strauss Syndrome with pleural involvement.

A 51-year-old Japanese man with Churg-Strauss Syndrome (CSS) diagnosed by pleural biopsy is described. He was hospitalized because of high fever and bilateral knee, elbow and shoulder joint pain. Chest roentgenogram and chest computed tomography (CT) scan revealed bilateral massive pleural effusion. Pleural biopsy revealed eosinophilic infiltration and necrotizing granulomas. He was treated with oral prednisolone and his symptoms improved. This is the first report of CSS diagnosed by pleural biopsy.

Churg-Strauss Syndrome↗
PubMed2000

Use of photic feedback as an adjunct treatment in a case of Miller Fisher syndrome.

Photic Feedback treatment of a patient diagnosed with Miller Fisher syndrome has resulted in the rapid and permanent remission of symptoms. During Photic Feedback treatment, the CD20 appeared to be slightly increased. This may have been associated with changes in humoral immunity. The present clinical observation of a single patient suggests that Photic Feedback treatment should be investigated as a possible adjunct therapy for patients who suffer from polyneuropathies, such as Miller Fisher syndrome, within a carefully controlled clinical trial.

Adult↗
PubMed2000

C-Cbl protein in human cancer tissues is frequently tyrosine phosphorylated in a tumor-specific manner.

To search for the signaling pathway relevant to the tumorigenesis in human, we examined the expression and tyrosine phosphorylation of c-cbl proto-oncogene product, c-Cbl, in various human cancer cell lines and surgical specimens. In cells derived from human cancer, we found constitutive tyrosine phosphorylation of c-Cbl protein, whereas its phosphorylation was undetectable in control ECV304 cells. Expression and tyrosine phosphorylation of c-Cbl was also examined in various surgical specimens. Thirty-six surgical specimens obtained from human tumor tissues were studied: 9 gastric carcinomas, 10 colon carcinomas, 6 renal carcinomas, 2 hepatomas, 2 brain tumors, 2 uterus tumors, 1 breast carcinoma, 1 thyroid tumor, 1 bladder tumor and 2 lung carcinomas. We found tyrosine phosphorylation of c-Cbl protein in 12 cases (33%) of these tumor tissues in a tumor-specific manner. These results suggest the importance of c-Cbl signaling in tumorigenesis in human.

Carcinoma↗
PubMed2000

[Changes in brain metabolites under combined mild-hypothermia and isoflurane anesthesia in rat with temporal brain ischemia].

The significance of mild-hypothermia as a treatment of brain ischemia-induced neuronal cell death was investigated by measurement of hippocampul excitatory amino acids, brain lactate and energy-charge just after 10 min of transient forebrain ischemia in a rat model with four vessels occluded. After 10 min of ischemia, cerebral circulation was restored. At that time, in the control group transient increases of hippocampul aspartate and glutamic acid levels were observed. Furthermore, brain lactate levels were also elevated but the energy-charge was reduced. These significant changes were observed in the non-isoflurane anesthesia and mild-hypothermia rats (control group). However, in rats with treatment of either isoflurane or mild-hypothermia, the excessive amount of amino acids and the significant fluctuation of brain metabolic/energy pathway seen in the control group were suppressed. Particularly, in the combined treatment group, these increased and decreased phenomena induced by brain ischemia were significantly inhibited. In a group of pre- and post-treatment of mild-hypothermia, the maximum peak of lactate was significantly less than that seen in the control group, although the sustained increased level of lactate was detected. These results indicate that the combined treatment with isoflurane anesthesia and mild-hypothermia is a suitable treatment for the brain dysfunction induced by ischemia and that the sustained hypothermia may help restore brain lactate levels after brain ischemia because of the lasting anaerobic metabolism.

Anesthesia, Inhalation↗
PubMed1999

An FH domain-containing Bnr1p is a multifunctional protein interacting with a variety of cytoskeletal proteins in Saccharomyces cerevisiae.

Proteins containing formin homology domains, FH1 and FH2, are involved in cytokinesis or establishment of cell polarity in a variety of organisms. Bni1p and Bnr1p are FH proteins and potential targets of the Rho family small GTP-binding proteins in S. cerevisiae. We have shown that Bnr1p is localized at the bud neck to interact with Hof1p, involved in cytokinesis. We report here that the overexpression of BNR1 causes a cytokinesis deficiency which is similar to the phenotypes of the septin mutants, including cdc3, cdc10, cdc11, and cdc12. The region required for the septin mutant phenotypes was mapped to Bnr1p (35-500), which coincided with the region required for the bud-neck localization. To further isolate a gene interacting with BNI1 or BNR1, a multicopy suppressor of the bni1 bnr1 mutant was isolated. This gene encoded Smy1p, a kinesin-related protein. Bnr1p, but not Bni1p, directly interacted with the C-terminal region of Smy1p. The Smy1p-interacting region of Bnr1p was mapped to a region containing the FH2 domain. Bnr1p also directly interacted with Bud6p, a novel actin-binding protein. Bnr1p is thus a multifunctional protein which interacts with the septin system, a microtubule-dependent motor protein, and the actin system, to regulate cytoskeletal functions in S. cerevisiae.

Carrier Proteins↗
PubMed1999

Coendocytosis of cadherin and c-Met coupled to disruption of cell-cell adhesion in MDCK cells--regulation by Rho, Rac and Rab small G proteins.

Both E-cadherin, a cell-cell adhesion molecule, and c-Met, the hepatocyte growth factor (HGF)/scatter factor (SF) receptor, were colocalized at cell-cell adhesion sites of MDCK cells. HGF/SF or a phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA), induced disruption of cell-cell adhesion, which was accompanied by endocytosis of both E-cadherin and c-Met. Reduction of medium Ca2+ to a micromolar range showed the same effects. Re-increase in medium Ca2+ to a millimolar range formed cell-cell adhesion, which was accompanied by exocytosis of E-cadherin and c-Met, followed by their re-colocalization at the cell-cell adhesion sites. These results suggest that E-cadherin and c-Met are colocalized at cell-cell adhesion sites and undergo co-endo-exocytosis. We have previously shown that TPA does not induce disruption of cell-cell adhesion and subsequent scattering of MDCK cells stably expressing a dominant active mutant of RhoA or Rac1 small G protein or a dominant negative mutant of Rab5 small G protein. In these cell lines, the HGF- or TPA-induced coendocytosis of E-cadherin and c-Met was inhibited, but the coendocytosis of E-cadherin and c-Met in response to reduction of medium Ca2+ was not affected. Wortmannin, an inhibitor of phosphoinositide (PI) 3-kinase, inhibited the HGF-induced disruption of cell-cell junction and endocytosis of E-cadherin and c-Met, but not the TPA-induced ones. These results suggest that disruption of cell-cell adhesion is involved in the HGF- or TPA-induced coendocytosis of E-cadherin and c-Met in MDCK cells, and that the Rho and Rab family members indirectly regulate this coendocytosis. In addition, coendocytosis of E-cadherin and c-Met in response to HGF is partly mediated by PI 3-kinase. The cross-talk between cell-cell and cell-matrix adherens junctions is discussed.

Animals↗
PubMed1999

Method for the simultaneous determination of losartan and its major metabolite, EXP-3174, in human plasma by liquid chromatography-electrospray ionization tandem mass spectrometry.

A liquid chromatography-electrospray ionization tandem mass spectrometric method was developed for the simultaneous determination of losartan and its major active metabolite, EXP-3174, in human plasma. The two analytes and the internal standard (DuP-167) were extracted from plasma under acidic conditions by using solid-phase extraction cartridges containing a sorbent of copolymer, poly(divinylbenzene-co-N-vinylpyrrolidone). The analytes were separated by LC equipped with a reversed-phase C18 column, and introduced into the mass spectrometer via the electrospray ion source with pneumatically-assisted nebulization. For LC-MS-MS samples, an isocratic mobile phase consisting of [0.1% triethylamine-0.1% acetic acid (pH 7.1)]-acetonitorile (65:35, v/v) was used, and the assay was monitored for the negative fragment ions of the analytes. The method demonstrated linearity from 1 to 1000 ng/ml for both losartan and EXP-3174. The limit of quantification for both compounds in plasma was 1 ng/ml. This assay method may be useful for the measurement of levels of the two compounds in clinical studies of losartan.

Antihypertensive Agents↗
PubMed1999

The ability of Vibrio vulnificus to use a synthetic hydrophilic heme compound, Fe-TPPS, as a single iron source.

Vibrio vulnificus, an opportunistic human pathogen, can obtain iron from a variety of heme proteins. This process involves the digestion of heme proteins by an exoprotease to liberate protoheme (iron-protoporphyrin IX). In the present study, we tested whether this pathogen also uses a synthetic heme compound, Fe-alpha,beta,gamma,delta-tetraphenylporphine tetrasulfonic acid (Fe-TPPS), as an iron source. When inoculated into a medium containing Fe-TPPS, V. vulnificus L-180 multiplication was seen to be dependent on the concentration of the synthetic heme compound; a mutant lacking the ability to utilize protoheme did not multiply. Cells of the strain grown under the iron-restricted condition showed time-dependent uptake of Fe-TPPS. The ability to use either protoheme or Fe-TPPS was significantly reduced by the addition of an excess amount of free TPPS or Cu-TPPS. The data suggest that, V. vulnificus may assimilate Fe-TPPS, at least partially, through the same system as that for protoheme.

Blood↗
PubMed1999

Elevation of anti-cytokeratin 19 antibody in sera of the patients with idiopathic pulmonary fibrosis and pulmonary fibrosis associated with collagen vascular disorders.

It has been suggested that cytokeratin 19 is expressed in regenerated bronchoepithelial cells in patients with pulmonary fibrosis, and serum cytokeratin 19 fragment is elevated in patients with pulmonary fibrosis. We hypothesized that serum antibodies to cytokeratin 19 may be formed in patients with pulmonary fibrosis. To prove the existence of anti-cytokeratin 19 antibodies in patients' sera, human recombinant cytokeratin 19 was stained with patients' sera by a Western immunoblot. Then, we tried to establish an enzyme-linked immunosorbent assay to quantitate anti-cytokeratin 19 antibody in the sera of patients with idiopathic pulmonary fibrosis (IPF) and pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). We demonstrated the anti-cytokeratin 19 antibody in patient' sera by a Western immunoblot. In patients with IPF and PF-CVD, significantly high anti-cytokeratin 19 antibody was demonstrated compared with normal volunteers, patients with chronic bronchitis, and patients with pneumonia. These results suggest that anti-cytokeratin 19 antibody may have played a role in the process of lung injury in pulmonary fibrosis.

Adult↗
PubMed1999

Successive follow-up of chest computed tomography in patients with Mycobacterium avium-intracellulare complex.

The aim of this study was to evaluate the changes in chest CT findings examined successively in patients with Mycobacterium avium-intracellulare complex (MAC) infection. We carried out a retrospective study of 25 patients with MAC infection who had serial CT scans. Patients included 18 women and seven men with a median age of 66 years. Mean (+/- SE) follow-up interval between the first and second CT was 27.5 +/- 4.2 months. The serial chest CT scans were reviewed with consensus reading by two observers. At the first chest CT examination, we found the following: bronchiectasis (in 133 of 250 fields), cavity formation (11 of 250 fields), centrilobular nodules (167 of 250 fields), air-space disease (30 of 250 fields) and nodules (81 of 250 fields). The middle lobe and lingula were frequently involved. Centrilobular nodule scores improved in seven patients; disease progressed in nine patients and was stable in nine patients. In addition, bronchiectasis scores improved in four patients; disease progressed in 15 patients and was stable in six patients. The score of bronchiectasis in the second CT was significantly higher than in the first CT. In conclusion, our data suggest that centrilobular nodules and bronchiectasis are frequent observations in patients with MAC. In addition, progression of bronchiectasis appeared to be caused by MAC infection.

Adult↗
PubMed1999

Clinical features of non-specific interstitial pneumonia.

The clinical features of 24 patients with non-specific interstitial pneumonia (NIP) were evaluated. The patients consisted of seven men and 17 women, with a median age of 60 years. In seven patients, the disease was idiopathic and eight had collagen vascular diseases. Cough, dyspnoea and fever were frequently observed. The time interval between the onset of symptoms and open lung biopsy was 3 months. Mild increases of IgG, CRP, and LDH were also frequently observed. The average per cent VC was 65.1 +/- 3.2% and the average PaO2 was 71.3 +/- 2.4 Torr. Bronchoalveolar lavage was done in 20 patients, and a moderate increase in lymphocytes (27.8 +/- 6.7%) with a low CD4/CD8 ratio (0.86 +/- 0.22) was observed. Multiple patchy infiltration or diffuse interstitial shadows, located predominantly in the lower fields of both lungs were the characteristic chest CT findings. Lung biopsies in this group were characterized by varying proportions of chronic interstitial inflammation and fibrosis which was temporarily uniform. Patients were given steroid pulse therapy or oral steroids. The results were mild to marked improvements in chest roentgenographic findings and lung functions. Four patients (16.7%) died because of respiratory failure caused by NIP. This is the first report to describe clinical features of NIP since the original report by Katzenstein and Fiorelli.

Adrenal Cortex Hormones↗
PubMed1999

Elevated serum and BAL cytokeratin 19 fragment in pulmonary fibrosis and acute interstitial pneumonia.

Cytokeratin 19 fragment (CK19) levels in serum have already been documented as a useful tumour marker for lung cancer. In the present study, it was hypothesized that CK19 may be increased in the serum and epithelial lining fluid of the respiratory tract from patients with pulmonary fibrosis. CK19 was measured in the serum and bronchoalveolar lavage fluid (BALF) of patients with pulmonary fibrosis and the correlation between CK19 levels and clinical parameters evaluated. Nineteen patients diagnosed with idiopathic pulmonary fibrosis (IPF), eight with pulmonary fibrosis associated with a collagen vascular disorder (PF-CVD), seven patients with acute interstitial pneumonia (AIP), and 10 normal smokers as a control group were studied. CK19 levels in sera of patients with IPF and patients with PF-CVD were significantly increased compared to those of normal smokers. CK19 levels in sera of patients with AIP were significantly increased compared to those of other groups. CK19 values in the BALF of patients with pulmonary fibrosis were significantly elevated compared to those of normal smokers. CK19 values in sera charged according to the progression or improvement of the acute lung injury. Immunohistochemical study using pulmonary tissues obtained from patients with AIP demonstrated that the hyaline membrane and proliferating type II pneumocytes were stained by anti-human cytokeratin 19 antibody. These data demonstrated that the measurement of cytokeratin 19 fragment is a useful parameter to evaluate the activity of lung epithelial cell damage and repair.

Acute Disease↗
PubMed1999

Second lung adenocarcinoma after combination chemotherapy in two patients with primary non-Hodgkin's lymphoma.

We report a rare complication of a secondary malignant solid tumor in two patients with non-Hodgkin's malignant lymphoma who developed lung adenocarcinoma after treatments with combination chemotherapies. The first was a case of primary malignant lymphoma of the cervical spinal cord which had been previously treated with radiation to the spinal lesion and combination chemotherapies and entered complete remission. The patient was further treated for relapse with autologous bone marrow transplantation preconditioned with high-dose chemotherapy. Lung adenocarcinoma developed 5.5 years after the initial diagnosis. The second case of malignant lymphoma of lymph nodes did not respond to conventional combination chemotherapies and did not enter remission. Lung adenocarcinoma developed 1 year after the initial diagnosis. The two patients died of lung carcinoma. The clinical profiles of these cases are presented and the causal relationship of primary malignant neoplasms to the second malignant neoplasms is discussed.

Adenocarcinoma↗