Biomedical subjects

Y Kamio

Publications and source records attributed to Y Kamio.

At least 127 records · Page 7Linked to original sources

PubMed1993

Gamma-hemolysin genes in the same family with lukF and lukS genes in methicillin resistant Staphylococcus aureus.

Cloning and DNA sequencing of gamma-hemolysin genes from two strains of Staphylococcus aureus showed three open reading frames, transcribed serially within the sequenced 4353 nucleotide bases. In this report, from the nucleotide sequence, we demonstrate that leukocidin and gamma-hemolysin share the F or H gamma I component and the specificity of both toxins depends on this component.

Amino Acid Sequence↗

PubMed1993

Purification and properties of collagenase from Cytophaga sp. L43-1 strain.

A collagenolytic bacterial strain was isolated from soil and was identified as Cytophaga sp. It produced several kinds of collagenase and protease. From the supernatant of a culture, a collagenase was purified as a single protein band upon SDS-PAGE and its molecular mass was estimated to be 120 kDa. Collagen and gelatin were good substrates for this enzyme. beta-Casein was cleaved by this enzyme at several sites.

Amino Acid Sequence↗

PubMed1993

Purification and characterization of a thermostable neutral metalloprotease I from Chloroflexus aurantiacus J-10-fl.

Chloroflexus aurantiacus J-10-fl was found to contain two types (protease I and protease II) of thermostable proteases which were separated by Butyl-Toyopearl 650 M chromatography. Protease I was purified to electrophoretic homogeneity from the culture broth of C. aurantiacus J-10-fl. The molecular mass of protease I was estimated to be approximately 66 kDa by SDS-PAGE, and the value of approximately 66 kDa was also obtained by the Hedrick-Smith method, indicating that protease I was a monomer. The isoelectric point was 6.2. Protease I activity was inhibited by metalloprotease inhibitors such as EDTA, EGTA, and o-phenanthroline. The optimum pH for the activity of protease I was around 8.0. Addition of Ca2+ increased the pH and heat stabilities of protease I. The activity was stable between pH 4.0-11.0 and up to 75 degrees C, and the maximum activity was observed at 70 degrees C in the presence of 2 mM CaCl2. Protease I was resistant to the treatment by denaturing reagents (8 M urea or 1% SDS) at pH 8.0 and 20 degrees C for 24 h. The sites of cleavage in oxidized insulin B chain by protease I were similar to those by other microbial neutral metalloproteases. Elastase activity of protease I was not detected.

Amino Acid Sequence↗

PubMed1993

Molecular cloning and nucleotide sequence of the pectate lyase gene from Pseudomonas marginalis N6301.

Pectate lyase was purified approximately 29-fold to electrophoretic homogeneity from Pseudomonas marginalis N6301. A pectate lyase (PL; EC4.2.2.2) gene of the strain was cloned and expressed in Escherichia coli. The nucleotides of the PL gene (pel) were sequenced. An open reading frame that encodes a polypeptide (molecular weight: 40,812) composed of 380 amino acids including a 29 amino acid signal peptide was assigned. The structural gene of pel consisted of 1140 base pairs. The nucleotide sequence of the 5'-flanking region of pel showed a consensus sequence of the promoter region of the pectin lyase gene (pnl) in P. marginalis N6301, a Pribnow box, and a ribosome binding site as found in E. coli.

Amino Acid Sequence↗

PubMed1993

Correlation of nonspecific bronchial responsiveness to baseline pulmonary function in patients with asthma and sinobronchial syndrome.

To examine the relationship of nonspecific bronchial responsiveness to baseline pulmonary function, and to compare the reactivity in asthma and sinobronchitis, we measured the provocative concentration of methacholine, causing a 20% fall in forced expiratory volume in one second (PC20-FEV1) in 82 asthmatic patients, 54 patients with sinobronchial syndrome and 57 normal subjects. Log PC20-FEV1 was directly correlated to baseline pulmonary function. The strongest correlation was seen between log PC20-FEV1 and baseline FEV1 as a % of the predicted FEV1 (%FEV1), both in asthma (log PC20-FEV1 = 0.020 x %FEV1-1.988, r = 0.54, p < 0.01) and in sinobronchial syndrome (log PC20-FEV1 = 0.025 x %FEV1-1.233, r = 0.64, p < 0.01). From the regression equations, the mean value of PC20-FEV1 at 100% FEV1 was calculated as 1.02 and 18.5 mg/ml in asthmatic and sinobronchitic patients, respectively, and the value was 35.5 mg/ml in normal subjects. The PC20-FEV1 to %FEV1 relationship may be helpful to assess individually measured PC20-FEV1 values in patients with airway obstruction.

Adult↗

PubMed1993

Log normal distribution of bronchial responsiveness to methacholine in normal young adults.

It has not been well known whether or not the distribution of non-specific bronchial responsiveness is log normal in normal subjects. We measured bronchial responsiveness to methacholine using partial flow-volume curves. The expiratory flow at 40% (above RV) from the full forced vital capacity (MEF40) was obtained and used as a reference volume to compare the isovolume flow from the partial flow-volume curve (PEF40). Provocative concentrations of methacholine causing a 20% fall in FEV1 (PC20-FEV1) and a 35% fall in MEF40 (PC35-MEF40) and PEF40 (PC35-PEF40) were measured as indices of bronchial responsiveness in 93 Japanese college students including 36 atopic and 57 non-atopic normal subjects. A 35% or more fall in PEF40 was produced by 160 mg/ml or less of methacholine in all the subjects whereas 20% or more fall in FEV1 did not occur in 4 atopic and 10 non-atopic subjects, and 35% or more fall in MEF40 did not occur in 4 non-atopic subjects at the final concentration of methacholine (160 mg/ml). The geometric mean value of PC35-PEF40 was 2.41 (GSEM, 1.21), 3.74 (GSEM, 1.16), and 3.16 (GSEM, 1.12) mg/ml in atopic, non-atopic, and both subjects, respectively. The distribution of log PC35-PEF40 could not be differentiated at the 5% level from a normal distribution using chi-square test to examine the goodness of fit in each group of subjects and in the whole subjects. These results directly confirm the log normal distribution of non-specific bronchial responsiveness in normal humans.

Adult↗

PubMed1993

[Bronchial provocation test in bronchial asthma].

Methacholine provocation test, bronchial reversibility test, aspirin inhalation test, and cough provocation test have been performed at our institute to examine pathophysiology and to diagnose bronchial diseases. Bronchial responsiveness to methacholine correlated to baseline pulmonary functions, especially to % predicted value of forced expiratory volume in 1 second (%FEV1) in asthma and sinobronchial syndrome. Bronchial reversibility was greater with beta 2-agonists than with muscarinic antagonists in asthma while it was less with beta 2-agonists than with muscarinic antagonists in sinobronchial syndrome. Our protocol for aspirin inhalation test consists of a screening test and threshold measurement test and is useful for diagnosis of analgesics-induced asthma. Capsaicin provocation test to measure airway cough receptor sensitivity is used to diagnose chronic cough.

Aspirin↗

PubMed1992

Molecular cloning and nucleotide sequence of leukocidin F-component gene (lukF) from methicillin resistant Staphylococcus aureus.

A lukF gene encoding F-component of Staphylococcal leukocidin from methicillin resistant Staphylococcus aureus (MRSA) was cloned. The nucleotide sequence of lukF gene was determined. The sequence data have revealed an open reading frame, which encodes a polypeptide with 323 amino acid residues. Inspection of the amino acid sequence deduced from nucleotide sequence of lukF and that from F-component of leukocidin from S. aureus V8 clarified that pre-matured F-component contains a typical signal peptide at the NH2 terminus and ATG starting codon for pre-matured F-component was present one base downstream to the TGA which is translation termination codon for S-component of leukocidin [A. Rahman et al. (1991) Biochem. Biophys. Res. Commun. 181, 138-144]. The nucleotide sequence of 5'-flanking region of lukF showed the presence of the consensus sequence of ribosome binding site in the internal region of the structural gene of S-component. The lukF was transcribed in the same direction as that of lukS. No Pribnow box can be discerned in the intercistronic region between the lukS and lukF genes. The amino acid sequence homology between S- and F-components was 31%. F-component was expressed in Escherichia coli DH5 alpha harboring plasmid pFRK92 which contained lukF gene.

Amino Acid Sequence↗

PubMed1992

Molecular cloning and nucleotide sequence of a pectin lyase gene from Pseudomonas marginalis N6301.

A pectin lyase (PNL;EC4.2.2.10) gene of Pseudomonas marginalis N6301 was cloned and expressed in Escherichia coli. We purified PNL from P. marginalis N6301 and determined N-terminal 33 amino acids sequence. From this sequence, we synthesized two oligonucleotide probes. From the analysis of Southern hybridization, 2. 1kb EcoRI-SmaI fragment from the chromosomal DNA of P. marginalis was found to hybridize with oligonucleotide probes. Then, we cloned the fragment into pUC119 vector and transformed into E. coli DH5 alpha. A plasmid thus obtained was designated as pPNL6301. E. coli DH5 alpha harboring pPNL6301 expressed PNL activity. The nucleotide sequence of pn1 gene in the plasmid pPNL6301 encoding PNL from P. marginalis N6301 was determined. The structural gene of pn1 consisted of 936 base pairs. An open reading frame that encodes a 34,103 dalton polypeptide composed of 312 amino acids was assigned. The molecular weight of the polypeptide predicted from the amino acid composition was close to that of PNL of P. marginalis N6301 determined. The nucleotide sequence of the 5'-flanking region of pn1 gene showed the presence of the consensus sequence of LexA binding site, Pribnow box and ribosome binding site as found in Escherichia coli. The amino acid sequence homology of PNLs and nucleotide sequence homology of pn1 gene between P. marginalis N6301 and E. carotovora Er were 60.8% and 57.2%, respectively.

Amino Acid Sequence↗

PubMed1992

Tachyphylaxis to capsaicin-induced cough and its reversal by indomethacin, in patients with the sinobronchial syndrome.

Cough reflex testing with capsaicin has been used to study the pathophysiology of the cough reflex and the antitussive effects of various drugs. Although the reproducibility of capsaicin-induced cough has been well established in normal subjects, it is not known if prior challenge with capsaicin reduces the subsequent cough response to inhaled capsaicin in patients with the sinobronchial syndrome, a condition characterized by chronic upper and lower airway inflammation. Measurement of the capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was repeated four times at intervals of 15, 30 and 60 min in eleven patients with the SBS and ten normal subjects. The cough thresholds at 15, 30 and 60 min were greater than the initial value in patients with the SBS but not in normal subjects. In addition, we examined the effect of 4 days treatment with indomethacin (100 mg/day) on the cough thresholds measured twice at an interval of 15 min in eight patients with the SBS. Indomethacin increased the initial cough threshold and reduced the increment in the post-15 min cough threshold from the initial value compared with placebo, thus reducing the tachyphylaxis. These results indicate that chronic airway inflammation may be responsible for the decreased response (tachyphylaxis) to repeated inhalation of capsaicin, and suggest that cyclooxygenase products released by the airway inflammation may be involved in tachyphylaxis, cough receptor sensitivity to inhaled capsaicin, or both, in patients with the SBS.

Adult↗

PubMed1992

Purification and Properties of a Maltotetraose- and Maltotriose-Producing Amylase from Chloroflexus aurantiacus.

A maltotetraose- and maltotriose-producing amylase which is stable at alkaline pHs and high temperatures was detected in the culture filtrate of a strain of Chloroflexus aurantiacus J-10-F1, a thermophilic, green, photosynthetic bacterium. The enzyme was purified to homogeneity, as demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, by means of ultrafiltration, ammonium sulfate fractionation, and DEAE-cellulose, hydroxyapatite, and high-performance liquid chromatographies. The molecular mass of the purified enzyme was estimated to be about 210,000 Da. The isoelectric point of the enzyme was estimated to be 6.24 by polyacrylamide gel electrofocusing. The amylase was stable up to 55 degrees C and at alkaline pHs of up to 12.0. The optimum pH and temperature of the enzyme activity were 7.5 and 71 degrees C, respectively. Metal ions such as Hg, Zn, Cu, Mn, and Ni strongly inhibited the enzyme activity. The enzyme activity was reactivated specifically by Ca after the enzyme was treated with 1 mM EDTA. This enzyme could digest various kinds of raw-starch granules from corn, cassava, and potato. Both maltotetraose and maltotriose were formed as the main enzymatic products from soluble starch.

Journal Article↗

PubMed1992

Effects of methacholine induced bronchoconstriction and procaterol induced bronchodilation on cough receptor sensitivity to inhaled capsaicin and tartaric acid.

BACKGROUND: The direct effect of bronchoconstriction on cough receptor sensitivity is unknown, and the antitussive effect of beta 2 adrenergic agonists in man has been controversial. This study was designed to throw light on these questions. METHODS: The threshold of the cough response to inhaled capsaicin, a stimulant acting on C fibre endings, and tartaric acid, a chemostimulant, was measured before and 10 minutes after inhalation of methacholine, which caused a nearly 20% fall in forced expiratory volume in one second (FEV1), in 14 normal subjects (study 1), and also before and 30 minutes after inhalation of procaterol (30 micrograms), placebo, and saline in eight normal subjects (study 2). Progressively increasing concentrations of capsaicin and tartaric acid solutions were inhaled for 15 seconds by mouth tidal breathing at one minute intervals and cough threshold was defined as the lowest concentration of capsaicin and tartaric acid that elicited five or more coughs. RESULTS: In study 1 the geometric mean values of the cough threshold of response to capsaicin and tartaric acid before methacholine callenge, 2.98 (GSE 1.30) micrograms/ml and 46.6 (1.22) mg/ml, were not significantly different from those of the response to methacholine inhalation, 3.45 (1.33) micrograms/ml and 32.9 (1.37) mg/ml. In study 2 the geometric mean value of the cough threshold of response to capsaicin before inhalation of procaterol (4.61 (GSE 1.84) micrograms/ml) was not different from that after inhalation of procaterol (4.61 (GSE 1.84) micrograms/ml), which had significant bronchodilator effects. The cough threshold was not altered by placebo or saline. CONCLUSIONS: These findings suggest that muscarinic receptor stimulation, bronchoconstriction, beta 2 receptor stimulation, or bronchodilation might have no direct effect on the sensitivity of the cough receptors in normal subjects.

Adult↗

PubMed1992

Effect of a M1-selective muscarinic receptor antagonist (pirenzepine) on basal bronchomotor tone in young women.

To examine the role of muscarinic M1-receptors in vagally mediated basal bronchomotor tone, we studied the effects of inhaled pirenzepine, which is a M1-receptor antagonist, on basal bronchomotor tone in 8 young women. To obtain dose-response curves to inhaled pirenzepine, we measured partial and full flow-volume curves before and 30 min after inhalation of each concentration of pirenzepine (3.25-200 micrograms/ml). Maximum expiratory flow on partial flow-volume curve at 25% forced vital capacity (PEF25) was measured as an index showing basal bronchomotor tone. The dose-response curve of the percent increase in PEF25 by pirenzepine was biphasic in shape. PEF25 was significantly increased by 3.12 (14.5 +/- 5.8%), 6.25 (15.5 +/- 4.2%), 12.5 (20.0 +/- 0.29%) and 200 micrograms/ml (17.3 +/- 5.9%) of pirenzepine, but not by 25 (9.6 +/- 5.6%), 50 (9.4 +/- 6.2%) and 100 micrograms/ml (14.4 +/- 6.2%) of pirenzepine. The percent increase in PEF25 by 40 micrograms of ipratropium bromide was 66.2 +/- 14.2%. These results suggest that the role of M1-receptors in vagally mediated basal bronchomotor tone may be significant but little compared with M3-receptors in normal humans.

Adult↗

PubMed1992

Molecular cloning and sequencing of the extracellular pectate lyase II gene from Erwinia carotovora Er.

Erwinia carotovora Er produces three extra-cellular pectate lyases (PL I, II, and III). The gene for pectate lyase II (pelII) of E. carotovora Er was cloned and expressed both in Escherichia coli and E. carotovora Er. Localization experiments in E. coli showed that PL II was exclusively in the cytoplasmic space, while PL II was excreted into the culture medium. The complete nucleotides of the pelII gene were sequenced and found to include one open reading frame of 1122 bp coding for a protein of 374 amino acid residues. From comparison of the N-terminal amino acid sequence between the purified PL II and the deduced protein from the nucleotide sequence we reached the conclusion that the mature protein is composed of 352 amino acids with a calculated molecular weight of 38,169 and is preceded by a typical signal sequence of 22 amino acid residues. PL II had 90.1% and 82.9% homologies with PL I and PL III in amino acid sequence, respectively.

Amino Acid Sequence↗

PubMed1992

Cough threshold to inhaled tartaric acid and bronchial responsiveness to methacholine in patients with asthma and sino-bronchial syndrome.

To evaluate the effect of chronic airway inflammation on cough sensitivity and bronchial responsiveness, we measured the cough threshold to tartaric acid and bronchial responsiveness to methacholine (PC20-FEV1) in 13 asthmatic, 13 bronchitic (sino-bronchial syndrome) and 49 healthy non-atopic subjects. All subjects were non-smokers. The geometric mean value of the cough threshold was 9.55, 5.62 and 12.3% in asthmatic, bronchitic and normal subjects, respectively. The value in bronchitic subjects was significantly (p less than 0.02) lower than that in normal subjects. The geometric mean value of PC20-FEV1 in asthmatic subjects (0.63 mg/ml) was significantly lower than those in bronchitic (8.7 mg/ml) (p less than 0.01) and normal subjects (21.4 mg/ml) (p less than 0.01). There was no correlation between cough threshold and PC20-FEV1 values [correlation coefficient (r) = 0.06, p greater than 0.1]. These results indicate that cough sensitivity is potentiated by chronic airway inflammation in bronchitis but not in asthma and suggest that cough sensitivity and bronchial responsiveness may be independently potentiated by different mechanisms resulting from chronic airway inflammation.

Adult↗

PubMed1992

[A case report of solitary bone cyst of rib detected from pathological fracture].

A case of solitary bone cyst of rib was reported. The patient was 28-year-old man who was admitted to our hospital complaining of chest pain caused by pathological fracture of the left 10th rib. Chest x-ray film revealed a solitary cystic lesion of the 10th rib. The tumor was removed by extrapleural rib partial resection and the histological examination confirmed the diagnosis of solitary bone cyst.

Adult↗

PubMed1992

Cough receptor sensitivity and bronchial responsiveness in normal and asthmatic subjects.

We examined whether airway cough receptor sensitivity correlates to nonspecific bronchial responsiveness. We measured cough threshold, the lowest concentration of inhaled tartaric acid eliciting five or more coughs, and the provocative concentration of methacholine producing a 20% fall in forced expiratory volume in one second (PC20FEV1) in 38 normal and 11 asthmatic subjects. All subjects were nonsmokers. The geometric mean value of PC20FEV1 was 25.7 mg.ml-1 (GSEM1.29) and 0.63 mg.ml-1 (GSEM1.29) and the geometric mean value of the cough threshold was 115 mg.ml-1 (GSEM1.20) and 95.5 mg.ml-1 (GSEM1.35) in normal and asthmatic subjects, respectively. The PC20FEV1 was significantly (p less than 0.01) lower in asthmatics than in normals but the cough threshold did not differ between them. No significant correlation was observed between the cough threshold and the PC20FEV1 in normal subjects or in asthmatics. These results indicate that cough sensitivity does not directly correlate to bronchial responsiveness in normal and asthmatic subjects.

Administration, Inhalation↗

PubMed1991

Nucleotide sequence of leukocidin S-component gene (lukS) from methicillin resistant Staphylococcus aureus.

The nucleotide sequence of lukS gene encoding S-component of Staphylococcal leukocidin from methicillin resistant Staphylococcus aureus (MRSA) was determined. The structural gene of lukS consisted of 857 base pairs. An open reading frame that could encode a 35,556 dalton polypeptide consisting of 315 amino acids was assigned. The molecular size of the polypeptide predicted from the amino acid composition was close to the value of pre-matured S-component determined in DNA-directed transcription/translation system. Inspection of the amino acid sequence deduced from nucleotide sequence of lukS and that from S-component of leukocidin clarified that pre-matured S-component contains a typical signal sequence at the NH2 terminus. The amino acid sequence of predicted matured S-component correlated exactly with the known N-terminal 50 amino acid sequence of S-component from MRSA and S. aureus V8. The molecular size of the predicted matured protein was also close to the value of S-component determined in both MRSA and S. aureus V8. The nucleotide sequence of the 5'-flanking region showed the presence of the consensus sequence of ribosome binding site, Pribnow box and the RNA polymerase recognition site in Escherichia coli.

Amino Acid Sequence↗