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Biomedical subjects

E Yamaguchi

Publications and source records attributed to E Yamaguchi.

At least 127 records · Page 7Linked to original sources
PubMed1989

Measurement of catecholamines, their precursor and metabolites in human urine and plasma by solid-phase extraction followed by high-performance liquid chromatography with fluorescence derivatization.

A high-performance liquid chromatographic method is described for the determination in human urine and plasma of catecholamines, their precursor and metabolites [amino compounds (norepinephrine, epinephrine, dopamine, normetanephrine, metanephrine, 3-methoxytyramine and L-DOPA), acidic compounds (3,4-dihydroxymandelic acid, 3,4-dihydroxyphenylacetic acid, vanillylmandelic acid and homovanillic acid) and alcoholic compounds (3,4-dihydroxyphenylethyleneglycol and 4-hydroxy-3-methoxyphenylethyleneglycol)]. Urine (0.5 ml) containing 3,4-dihydroxybenzylamine and 4-hydroxy-3-methoxycinnamic acid (internal standards) is deproteinized with perchloric acid, and the resulting solution is fractionated by solid-phase extraction on a strong cation-exchange resin cartridge (Toyopak IC-SP S) into two fractions (amine fraction and acid-alcohol fraction), which include 3,4-dihydroxybenzylamine and 4-hydroxy-3-methoxycinnamic acid, respectively. Plasma (0.7 ml) is deproteinized in the presence of 3,4-dihydroxybenzylamine (internal standard) in the same manner, and the resulting solution is directly used as an acid-alcohol fraction, while an amine fraction is obtained as for urine. Each fraction is subjected to the previously established ion-pair reversed-phase chromatography with post-column derivatization involving coulometric oxidation followed by fluorescence reaction with 1,2-diphenylethylenediamine. The detection limits, at a signal-to-noise ratio of 5, of the compounds measured in urine are 300 pmol/ml for the two mandelic acids, 2-7 pmol/ml for the other acidic and alcoholic compounds, 12 pmol/ml for L-DOPA and 0.6-2 pmol/ml for the other amino compounds; the corresponding values for plasma samples are 80, 0.5-3, 10 and 0.6-3 pmol/ml, respectively.

Catecholamines↗
PubMed1989

Simultaneous high-performance liquid chromatographic determination of catecholamine-related compounds by post-column derivatization involving coulometric oxidation followed by fluorescence reaction.

A highly selective and sensitive high-performance liquid chromatographic method for the determination of catecholamines (norepinephrine, epinephrine and dopamine) and related compounds (L-DOPA, normetanephrine, metanephrine, 3-methoxytyramine, 3,4-dihydroxymandelic acid, 3,4-dihydroxyphenylacetic acid, homovanillic acid, vanillylmandelic acid, 3,4-dihydroxyphenylethylene glycol, 4-hydroxy-3-methoxyphenylethylene glycol and 4-hydroxy-3-methoxyphenylethanol) with a post-column technique involving coulometric oxidation followed by fluorescence derivatization is described. These compounds, 3,4-dihydroxybenzylamine and ferulic acid are separated within 35 min by ion-pair reversed-phase chromatography using acidic buffers (pH 3.1) with methanol-acetonitrile (3:2, v/v) gradient elution, and then oxidized by a commercial coulometric detector to the corresponding o-quinones, which are converted into fluorescent derivatives by reaction with 1,2-diphenylethylenediamine. The detection limits (signal-to-noise ratio = 3) on-column are 1.5-4 pmol for the two mandelic acids, 600 fmol for L-DOPA and 20-70 fmol for the others.

Catecholamines↗
PubMed1989

Cloning and nucleotide sequences of NADH-putidaredoxin reductase gene (camA) and putidaredoxin gene (camB) involved in cytochrome P-450cam hydroxylase of Pseudomonas putida.

Pseudomonas putida PpGl, which carries the CAM plasmid encoding enzymes involved in the degradation pathway of D-camphor, can utilize D-camphor as a sole carbon source. Cytochrome P-450cam and related enzymes participate in the early oxidation steps of D-camphor degradation metabolism. We cloned from a HindIII DNA library of PpGl a 2.9 kbp CAM segment which carries the major part of camA gene encoding NADH-putidaredoxin reductase and the entire camB gene encoding putidaredoxin. The 2.9 kbp CAM segment was adjacent to the 4.27 kbp HindIII CAM segment which has been previously cloned (Koga et al. (1986) J. Bacteriol. 166, 1089-1095). Thus, the total 7.17 kbp HindIII CAM directed all the genes responsible for early steps of D-camphor degradation, i.e. 5-exo-hydroxycamphor dehydrogenase (camD gene), cytochrome P-450cam (camC), NADH-putidaredoxin reductase (camA), and putidaredoxin (camB). These cam genes form an operon, camDCAB, and are under negative control by the gene camR located immediately upstream from the camD gene. The total number of amino acids deduced from the nucleotide sequence is 422 for putidaredoxin reductase, and 106 for putidaredoxin.

Amino Acid Sequence↗
PubMed1989

Interleukin 1 production by alveolar macrophages is decreased in smokers.

To evaluate the mechanism by which cigarette smoking suppresses pulmonary immune responses, we determined the capacity of alveolar macrophages (AM) to produce interleukin 1 (IL-1 in 32 normal subjects and in 40 patients with pulmonary sarcoidosis. The amount of IL-1 released from LPS-stimulated AM from smokers was significantly decreased compared with that in nonsmokers in both normal and sarcoid groups. The addition of indomethacin to the cultures in 18 normal subjects and in 22 patients with pulmonary sarcoidosis yielded similar results, thus excluding the possibility that this difference resulted from a difference in the amount of cyclooxygenase metabolites released in the culture supernatants. Similar results were obtained by enzyme-linked immunosolvent assay. Because IL-1 is thought to induce the accumulation of T cells at the site of disease and contribute to local cellular and humoral immunity of the lung, our data suggest that the reduced capacity of AM to release IL-1 in smokers affords partial protection against the initiation of immune responses in the lung and the development of granulomatous lung diseases.

Adult↗
PubMed1989

CD8+ cell-dominant alveolitis in pulmonary sarcoidosis.

A 55-year-old woman had bilateral hilar lymphadenopathy and retinouveitis. Microscopic examination of a biopsy specimen from a mediastinal lymph node revealed noncaseating epithelioid cell granulomas. Since granulomatous diseases of infectious origin and sarcoid reaction were reasonably excluded, she was diagnosed as having pulmonary sarcoidosis. Bronchoalveolar lavage findings were atypical in that the ratio of helper T cells to suppressor T cells (CD4/8 ratio) was 0.5 in two separate examinations, despite a moderately increased proportion of lymphocytes. Immunohistochemical examination of the lymph node also showed a predominancy of suppressor T cells. The inversion of the CD4/8 ratio suggests the presence of heterogeneity in the immunoregulatory mechanism in pulmonary sarcoidosis and may have a prognostic significance.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

[A case of pulmonary sarcoidosis with CD8 positive cell dominant alveolitis].

A 55-year-old woman was admitted for examination of bilateral hilar lymphadenopathy. Serum angiotensin converting enzyme was not elevated, but gallium-scan revealed an increased uptake in both lung hilus. The percentage of lymphocytes in the bronchoalveolar lavage fluid (BALF) was elevated (28.9%), and the proportion of OKIa1 positive cells was also elevated (50.5%). However, the ratio of cluster differentiation (CD) 4/8 was inverted at 0.5. Microscopic examination of the mediastinal lymph nodes revealed epithelioid cell granulomas without ceasation, and a diagnosis of sarcoidosis was made. Immunohistochemical examination of the lymph nodes showed predominancy of CD8 positive cells. Patients with pulmonary sarcoidosis having a low CD4/8 ratio in BALF are extremely rare in the early stage of sarcoidosis. The inverted CD4/8 ratio was of interest in regard to the pathogenesis of sarcoidosis.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

[A case of pulmonary sarcoidosis with calcification in the lung].

A 35 year-old male farmer presented with complaints of productive cough and sputum. The chest X-ray films showed reticulonodular shadows bilaterally in the upper and middle lung fields, segmental infiltration in the right lung, and no BHL. Tuberculin reaction was negative. Serum angiotensin converting enzyme level was 26.5 IU/ml. Precipitating antibodies for Thermophilic actinomycetes and M.f. were negative. BAL showed moderate lymphocytosis (24.3%), and CD 4/8 was 1.67. A biopsy specimen of right scalene lymph node showed epithelioid cell granulomas and TBLB epithelioid cell granulomas and spot-like calcification. Pulmonary sarcoidosis with calcification in the lung is very rare.

Adult↗
PubMed1988

Interleukins in pulmonary sarcoidosis. Dissociative correlations of lung interleukins 1 and 2 with the intensity of alveolitis.

To investigate whether interleukins are involved in the formation of alveolitis in pulmonary sarcoidosis, interleukin-1 (IL-1) production by LPS-stimulated alveolar macrophages (AM) and interleukin-2 (IL-2) production by PHA-stimulated lung and blood T-cells were determined in 35 untreated patients with pulmonary sarcoidosis. The amount of IL-1 produced by AM (BAL IL-1) was significantly increased in patients with pulmonary sarcoidosis compared with that in 18 control subjects. BAL IL-1 showed a significant positive correlation with the intensity of alveolitis assessed by the proportion of lymphocytes in bronchoalveolar lavage fluid (BALF) and the absolute number of lymphocytes per milliliter of BALF. However, the amount of IL-2 produced by lung T-cells (BALT IL-2) showed a significant negative correlation with the intensity of alveolitis. BALT IL-2 was significantly lower than the amount of IL-2 produced by blood T-cells (PBT IL-2). There was no correlation between PBT IL-2 and the intensity of alveolitis. These results suggest that IL-2 contributes to the formation and maintenance of alveolitis in pulmonary sarcoidosis, whereas IL-2 production by lung T-cells is suppressed to down-regulate the enhanced immune processes at the site of disease. The possibility that this hyporesponsiveness of lung T-cells to PHA has resulted from the modulation of the T3-T cell receptor complex remains to be determined.

Adolescent↗
PubMed1988

Plasma cells in the bronchoalveolar lavage fluid of a patient with eosinophilic pneumonia. Morphologic proof of local production of antibodies.

We describe a case of eosinophilic pneumonia in which plasma cells appeared in bronchoalveolar lavage fluid (BALF). A 49-year-old man presented with wheezing, lung infiltrates, peripheral eosinophilia, and extremely high IgE levels in serum and BALF. A differential count of BALF revealed 56.6 percent lymphocytes and 1.3 percent plasma cells. The appearance of plasma cells suggests local maturation of B cells and represents a morphologic proof of local production of immunoglobulins. The increased number of lymphocytes suggests their role in B cell differentiation via the lymphokine network.

Adult↗
PubMed1987

Association of HLA-DR with sarcoidosis. Correlation with clinical course.

HLA-DR typing was performed in 58 Japanese patients with sarcoidosis. We found a significantly increased frequency of HLA-DRw52 (p less than 0.0007; pc less than 0.009) and DR5J (p less than 0.004; pc less than 0.05). (Corrected probability value is given as pc.) In 34 of 58 patients the disease resolved spontaneously. There was no significant difference between the frequency of DRw52 and the resolution rate of disease. The frequency of DR5J was increased significantly in the unresolved cases. Our results also suggest that DRw52 is concerned with onset of sarcoidosis and DR5J antigen has an effect on the clinical course of this disease.

Adult↗
PubMed1986

camR, a negative regulator locus of the cytochrome P-450cam hydroxylase operon.

A 4.27-kilobase insert from a HindIII DNA library of Pseudomonas putida carrying the CAM plasmid allowed coordinate expression of genes camD and camC under control of camR, an upstream regulator. The camC gene specifies cytochrome P-450cam, and camD specifies the 5-exo-alcohol dehydrogenase. A 1.38-kilobase deletion from the insert results in the constitutive expression of genes camC and camD; transformation in trans restores the substrate control, indicating that camR is a negative regulator.

Alcohol Dehydrogenase↗