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A Nakazawa

Publications and source records attributed to A Nakazawa.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Antimicrobial activities of clarithromycin against recent obtained clinical isolates].

In order to evaluate antimicrobial activities of clarithromycin (CAM), minimum inhibitory concentrations (MICs) of CAM and control drugs were determined against clinical isolates that were obtained from outpatients in 1994 and 1996. The results are summarized as follows; 1. It was not showed that CAM-resistant strains were increasing among Staphylococcus spp., beta-streptococci, Moraxella subgenus Branhamella catarrhalis, Haemophilus influenzae, Bordetella pertussis, Campylobacter jejuni subsp. jejuni, Chlamydia trachomatis and Mycoplasma pneumoniae. It appeared that resistances to CAM and macrolides (MLs) were increasing among Streptococcus pneumoniae and Peptostreptococcus spp. 2. The drug susceptibility patterns to MLs were similar and detection frequencies of induced resistant strains that were resistant to only 14-membered ring MLs including CAM and constitutive resistant strains that were resistant to 14 and 16-membered ring MLs were high among Streptococcus pneumoniae and Peptostreptococcus spp. It appears that MLs-resistance systems are linked to each other, and that this was a cause of increasing MLs-resistance among these bacterial species. 3. Notwithstanding of antibiotic resistance problems, CAM is still useful since it maintains strong antimicrobial activities against M. (B.) catarrhalis, B. pertussis, C. jejuni subsp. jejuni, C. trachomatis and M. pneumoniae, and it controls arginate producing abilities of mucoide strains of Pseudomonas aeruginosa.

Anti-Bacterial Agents↗
PubMed1997

[The drug susceptibility pattern of the presumed etiologic agents of infectious enteritis including verotoxin-producing Escherichia coli O-157].

The drug susceptibility patterns were investigated for verotoxin-producing Escherichia coli (VTEC) including O-157, Salmonella spp., Vibrio parahaemolyticus and Campylobacter jejuni subsp. jejuni that were obtained in and after July 1996. The results are summarized as follows; 1. We found highly resistant strains of VTEC to tetracycline (TC) and ampicillin (ABPC). Minimum inhibitory concentrations (MIC) of some of the drugs against VTEC in an aerobic condition were significantly different from those in an anaerobic condition. For example, aerobic.anaerobic MIC ranges of the drugs tested were as follows: chroramphenicol (CP): 1.56-3.13 micrograms/ml.0.78-1.56 micrograms/ml, TC: 1.56-> 100 micrograms/ml.0.78-> 100 micrograms/ml, minocycline (MINO): 1.56-12.5 micrograms/ml.0.78-3.13 micrograms/ml, kanamycin (KM): 3.13-6.25 micrograms/ml.25-100 micrograms/ml, fosfomycin (FOM): 3.13-25 micrograms/ml.0.78-6.25 micrograms/ml, norfloxacin (NFLX): < or = 0.025-0.2 microgram/ml.< or = 0.025-0.2 microgram/ml, ABPC: 1.56-> 100 micrograms/ml.0.78-> 100 micrograms/ml and cefaclor (CCL): 1.56-25 micrograms/ml.56-12.5 micrograms/ml. MICs of CP and tetracyclines (TCs) in an anaerobic condition were lower by twofold and the MIC of FOM was lower by fourfold, but the variabilities of MIC-ranges of NFLX, ABPC and CCL were small. The MIC of KM was high. 2. We observed that some of Salmonella spp. were highly resistant to CP, TCs and MINO, and some were moderately resistant to NFLX. 3. The detection frequency of TC-resistant strains and NFLX-insensitive or resistant strains were high among C. jejuni subsp. jejuni. 4. Strains of V. parahaemolyticus and C. jejuni subsp. jejuni were mostly resistant to ABPC and CCL, MICs of which were in high ranges. 5. Fecal concentrations in MINO, KM, FOM and NFLX reported in literatures are high enough to have some antimicrobial activities, leed dose of ABPC and CCL are quite low.

Aerobiosis↗
PubMed1997

[Antimicrobial activities of clindamycin against clinical isolated Streptococcus pneumoniae].

We investigated antimicrobial activity of clindamycin (CLDM) against clinically isolated Streptococcus pneumoniae in 1996. The results are summarized as follows; 1. The detection frequencies of macrolides (MLs)-resistance against penicillin (PC)-susceptible S. pneumoniae (PSSP) was 48.0% and those against PC-intermediate S. pneumoniae (PISP)/ PC-resistant S. pneumoniae (PRSP) was 92.0%. 2. It was found that the ratio of MLs-inducible resistant strains of PSSP was 24.6% and that of PISP/PRSP was 66.0%. MLs-constitutive resistant strains of PSSP accounted for 24.0% and that of PISP/PRSP for 26.0%. MLs-constitutive resistant strains was relatively frequent in PSSP and MLs-inducible resistant strains was frequent in PISP/PRSP. 3. CLDM showed strong antimicrobial activity against MLs-inducible resistant strains. The MIC70 of CLDM against PSSP was < or = 0.025 microgram/ml and that against PISP/PRSP was 0.1 microgram/ml. From these results, it was suggested that CLDM is effective against the infection of PISP/PRSP where the detection frequency of MLs-inducible strains was high. 4. Antimicrobial activity of CLDM was found to be strong against MLs-inducible resistant strains, but to be weak against MLs-constitutive resistant strains. When S. pneumoniae is detected, susceptibility of the strain to CLDM should be examined.

Anti-Bacterial Agents↗
PubMed1996

Cloning of a cDNA encoding the human transforming growth factor-beta type II receptor: heterogeneity of the mRNA.

We have isolated two novel cDNAs encoding the transforming growth factor-beta (TGF-beta) type II receptor (TGF-beta IIR), termed TGF-beta IIR alpha and TGF-beta IIR beta 1 from a human fetal liver library. They have unique nucleotide (nt) sequences, compared with the reported TGF-beta IIR sequence, at the 5' end. Southern blot analysis using probes from each clone detected the specific genomic DNA fragments. RT-PCR analysis revealed a distinct pattern of expression for each isoform. These results indicated that TGF-beta IIR has heterogeneity in the structure, and the expression of TGF-beta IIR isoforms is differentially regulated. The heterogeneity of TGF-beta IIR molecules could be derived from alternative splicing and might elicit specific TGF-beta receptor functions.

Amino Acid Sequence↗
PubMed1996

Cloning and characterization of the gene encoding Halobacterium halobium adenylate kinase.

The gene (AK) encoding adenylate kinase (AK) of Halobacterium halobium was cloned. AK consisted of 648 bp and coded for 216 amino acids (aa). S1 mapping and primer extension experiments indicated that the transcription start point (tsp) was located immediately upstream from the start codon. The TAT-like promoter sequence was found at a position 20-24 bp upstream from tsp. The most striking property of the enzyme was a putative Zn finger-like structure with four cysteines. It might contribute to the structural stability of the molecule in high-salt conditions. Phylogenetic analysis indicated two lineages of the AK family, the short and long types which diverged a long time ago, possibly before the separation of prokaryotes and eukaryotes. Although the H. halobium AK belongs to the long-type AK lineage, it is located in an intermediary position between the two lineages of the phylogenetic tree, indicating early divergence of the gene along the long-type lineage.

Adenylate Kinase↗
PubMed1996

A genetic analysis system of Burkholderia cepacia: construction of mobilizable transposons and a cloning vector.

A genetic analysis system of Burkholderia cepacia (Bc) was developed which included transposon mutagenesis and complementation of mutation with the cloned genes of interest. To deliver the transposon in this multidrug-resistant microorganism, two plasmids, pKN30 and pKN31, were constructed which contained Tn5 derivatives, Tn5-30Tp and Tn5-31Tp, respectively, carrying KmR and TpR genes. The plasmids have the origin of ColE1 replication and the mobilization gene of RP4. Tn5-31Tp was mobilized to Bc KF1, a strain isolated from a pneumonia patient, by the transfer system of RP4 integrated in the chromosome of Escherichia coli (Ec). Selection with trimethoprim resulted in generation of a number of transposants of Bc KF1. Fourteen protease-deficient mutants were isolated, all of which contained a single transposon marker in the chromosome. Thirteen protease-deficient mutants were also lipase deficient. An Ec-Bc shuttle plasmid, pTS1209, was constructed that consists of oriColE1, oripSa, ApR and CmR genes, and several unique restriction sites for cloning. Plasmid pTS1209 was successfully employed for cloning genes of Bc involved in protease production.

Burkholderia cepacia↗
PubMed1996

Ancient divergence of long and short isoforms of adenylate kinase: molecular evolution of the nucleoside monophosphate kinase family.

Adenylate kinases (AK) from vertebrates are separated into three isoforms, AK1, AK2 and AK3, based on structure, subcellular localization and substrate specificity. AK1 is the short type with the amino acid sequence being 27 residues shorter than sequences of the long types, AK2 and AK3. A phylogenetic tree prepared for the AK isozymes and other members of the nucleoside monophosphate (NMP) kinase family shows that the divergence of long and short types occurred first and then differentiation in subcellular localization or substrate specificity took place. The first step involved a drastic change in the three-dimensional structure of the LID domain. The second step was caused mainly by smaller changes in amino acid sequences.

Adenylate Kinase↗
PubMed1996

[Rhabdomyolysis related-acute renal failure in a patient with hyperosmolar nonketotic diabetic coma (HNKC): demonstration of myoglobin casts after normalization of renal function].

We report a patient with rhabdomyolysis secondary to hyperosmolar nonketotic diabetic coma (HNKC), who progressed to acute renal failure. A 43-year-old male with diabetes mellitus for three years was admitted to our hospital because of loss of consciousness. The laboratory findings at admission were as follows: serum glucose 1792 mg/dl, serum Na 129 mEq/1, BUN 71 mg/d1, serum creatinine 3.3 mg/d1, CPK 715 IU/1, plasma osmolality 370 mOsm/1, and negative urine ketone bodies. A diagnosis of HNKC was made. On the 2nd day, he had oliguria and the serum creatinine increased despite adequate treatment of HNKC by the administration of intravenous fluid and insulin. On the 4th day, CPK reached 47,300 IU/1, and serum myoglobin was also increased, indicating rhabdomyolysis. His renal function improved gradually and was almost normalized on the 20th day. Renal biopsy on the 23rd day showed myoglobin at the distal renal tubules, which appeared to be involved in the pathogenesis of renal failure by rhabdomyolysis. However, we found little abnormality association with diabetic nephropathy in the renal tissue. Since HNKC is known to induce acute renal failure rarely without diabetic nephropathy, these findings suggested that the acute renal failure was caused mainly by the rhabdomyolysis. Acute renal failure induced by rhabdomyolysis in patients with HNKC is rare, but fatal. The present study showed that the measurement of serum CPK and urine myoglobin was helpful for early diagnosis. Only 12 cases have been reported to have developed renal failure due to rhabdomyolysis among patients with HNKC. To our knowledge, we demonstrated for the first time that myoglobin at the distal renal tubules after renal function was normalized.

Acute Kidney Injury↗
PubMed1996

[Antimicrobial activity of cefodizime against clinical isolates].

In order to evaluate antimicrobial activity of cefodizime (CDZM), minimum inhibitory concentrations (MICs) of CDZM and control drugs were determined against clinical isolates collected from nation-wide medical institutions and in our laboratory from September to December of 1992 and from September to December of 1995. The results are summarized as follows: 1. Bacterial species with no or few strains resistant to CDZM included Streptococcus pyogenes, Haemophilus influenzae, Citrobacter koseri, Proteus mirabilis and Neisseria gonorrhoeae. The range of MIC values of CDZM against Klebsiella pneumoniae was spread. Other strains, Streptococcus pneumoniae, Moraxella subgenus Branhamella catarrhalis, Escherichia coli, Citrobacter freundii, Enterobacter spp., Serratia marcescens, Proteus vulgaris, Morganella morganii, Providencia spp., Peptostreptococcus spp. and Bacteroides fragilis group were resistant to cephems including CDZM. 2. The MIC90's of CDZM were 0.05 approximately 3.13 micrograms/ml against Streptococcus spp., H. influenzae, M. (B.) catarrhalis, E. coli, Klebsiella spp., P. mirabilis, N. gonorrhoeae and Peptostreptococcus spp. obtained in 1995 that were frequently found in daily treatment of infections. It appears that the effectiveness of CDZM was still relatively high against community-acquired infections. 3. Among H. influenzae isolates included imipenem (IPM)-resistant and norfloxacin (NFLX)-resistant strains. The MIC-range of CDZM against strains collected in 1995 including IPM-resistant and NFLX-resistant strains was < or = 0.025 approximately 0.1 microgram/ml, and MIC90 against these strains was 0.05 microgram/ml. CDZM showed strong antimicrobial activities against H. influenzae strains resistant to carbapenems and new-quinolones.

Bacteria↗
PubMed1996

[Antimicrobial activities of cefetamet against clinical isolates from urinary tract infection].

In order to evaluate antimicrobial activity of cefetamet (CEMT), minimum inhibitory concentrations (MICs) of CEMT and control drugs were determined against Gram-negative rods mainly from complicated urinary tract infections examined in our laboratory from April to September of 1994. The results are summarized as follows; 1. The obtained strains were Citrobacter diversus 20, Citrobacter freundii 30, Enterobacter aerogenes 20, Enterobacter cloacae 30, Serratia marcescens 30, Proteus mirabilis 30, Proteus vulgaris 20 and Morganella morganii 30 strains, a total of 210 strains. 2. Excluding some resistant strains, the MIC-distribution showed showed that CEMT had strong antimicrobial activities against those strains from the MIC-distribution of this investigation. Compared to reports on CEMT in 1989, the MIC80 of CEMT in this investigation against clinical isolates were similar. The MIC50's of CEMT against E. aerogenes, S. marcescens, P. mirabilis, P. vulgaris and M. morganii in the previous examination were equal to or similar to the current results, but the MIC50's against C. freundii and E. cloacae were lower than the value of this report. The detection frequency of highly resistant strains of C. freundii and E. cloacae to cefteram and cefixime were similar to that of CEMT-resistant strains. Multiple drug resistant strains, among these bacterial species seemed to be increasing. 3. Compared to oral antibacterial agents of oxime cephems that were used in the past, CEMT showed higher peak values of urinary excretion concentration and higher blood levels were sustained for a longer period of time. CEMT-PI will be effective against urinary tract infections.

Ceftizoxime↗
PubMed1995

Cloning, DNA sequencing, and amino acid sequencing of catechol 1,2-dioxygenases (pyrocatechase) from Pseudomonas putida mt-2 and Pseudomonas arvilla C-1.

Catechol 1,2-dioxygenase catalyzes the oxygenative ring cleavage of catechol to form cis,cis-muconic acid and is encoded by a catA gene. We have cloned a catA gene from Pseudomonas putida mt-2 using a PCR product of amino acid sequence-based primers as a probe. The amino acid sequence deduced from the 930 nucleotides was in complete agreement with the chemically determined sequence of the protein. Crude extracts of Escherichia coli cells carrying the catA gene downstream from the lac promoter showed the enzyme activity. By using the same probe, we also cloned and sequenced the catA beta gene for catechol 1,2-dioxygenase isozyme beta beta from Pseudomonas arvilla C-1, which has three isozymes, alpha alpha, alpha beta, and beta beta (C. Nakai, H. Horiike, S. Kuramitsu, H. Kagamiyama, and M. Nozaki, 1990, J. Biol. Chem. 265, 660-665). There was very high homology between isozyme beta beta of the C-1 strain and the enzyme of the mt-2 strain in both the amino acid (98%) and the DNA sequences (97%). A preference for the use of codons terminating in C and G was found in the coding region of both the enzymes, which contributed to the high G + C content (65-66%) of the genes. A comparison of the DNA sequences of various catA genes from other sources revealed their common ancestry, whereas a comparison of the amino acid sequences of the enzymes revealed clear reflection of substrate specificity. Tyrosyl and histidyl residues for proposed ligands of ferric ion are conserved in all catechol 1,2-dioxygenases.

Amino Acid Sequence↗
PubMed1995

NM23-H1 and NM23-H2 messenger RNA abundance in human hepatocellular carcinoma.

nm23 was originally identified as an antimetastatic gene, the expression of which was inversely correlated with tumor metastatic potential in rodent model systems. Subsequently, two related human nm23 genes, nm23-H1 and nm23-H2, were identified. The relationship between expression of nm23-H1 and nm23-H2 in hepatocellular carcinoma specimens from 30 patients and metastatic potential was investigated with the use of a quantitative reverse transcription-PCR procedure. The abundance of nm23-H1 and nm23-H2 mRNA was compared with serum alpha-fetoprotein concentration, tumor size (maximum diameter), and histopathological parameters such as portal vein tumor thrombus, intrahepatic metastasis, capsular formation, capsular infiltration, differentiation of tumor cells, and TNM stage. The abundance of nm23-H1 mRNA showed a significant inverse correlation with intrahepatic metastasis and TNM stage. Furthermore, we confirmed that reduced expression of nm23-H1 mRNA was in accordance with a reduced amount of NM23-H1 protein using Western blot analysis. No correlation was apparent between nm23-H2 mRNA abundance and intrahepatic metastasis. These data support the conclusion that nm23-H1 may play a more important role than nm23-H2 in intrahepatic metastasis in hepatocellular carcinoma. Furthermore, nm23-H1 mRNA abundance may be a predictor of intrahepatic metastasis, the most important factor correlated with the metastatic potential of hepatocellular carcinoma.

Age Factors↗
PubMed1995

Effect of dietary linoleic acid on the tryptophan-niacin metabolism in streptozotocin diabetic rats.

To make clear the mechanism of change of tryptophan-niacin metabolism in diabetic rats, we investigated the effect of dietary linoleic acid on the tryptophan-niacin metabolites and the activity of liver, alpha-amino-beta-carboxymuconate-epsilon-semialdehyde decarboxylase (ACMSD), a key enzyme of tryptophan-niacin metabolism, in streptozotocin diabetic rats. Moreover, we investigated the involvement of linoleic acid in the induction of hepatic ACMSD activity by streptozotocin diabetes. In diabetic rats, the sum of urinary excretion of nicotinamide, N1-methylnicotinamide (MNA), N1-methyl-2-pyridone-5-carboxamide (2-Py) and N1-methyl-4-pyridone-3-carboxamide (4-Py) was higher in the fat free diet group than in the linoleic acid group, that was accompanied by the increase of tryptophan intake and reduction of body weight in the fat free diet group. In diabetic rats, hepatic ACMSD activity was higher in the fat free diet group than in the linoleic acid group. The results indicated that the induction of hepatic ACMSD activity by diabetes was not due to removal of the suppressive effect of the linoleic acid on the enzyme. In the diabetic+insulin group, hepatic ACMSD activity was significantly lower than in the diabetic group.

Animals↗
PubMed1995

Overexpression of Pseudomonas putida catechol 2,3-dioxygenase with high specific activity by genetically engineered Escherichia coli.

The cloned xylE gene encoding catechol 2,3-dioxygenase (metapyrocatechase) from TOL plasmid in Pseudomonas putida mt-2 has been expressed in Escherichia coli W3110 to a level of approximately 15% of the total soluble protein. Of the total iron in the crude extract, 45% was on the enzyme. The crystallized enzyme from E. coli had higher iron content (3.7 mol/mol enzyme) and specific activity (536 U/mg) than the enzyme from P. putida mt-2. However, no differences were observed in physicochemical, protein-chemical, and kinetic properties between the two enzymes. The enzyme was a homotetramer, and no changes were observed in the values of M(r) (136,000 +/- 5,000) and Stokes radius (4.26 nm) in the concentration range from 0.36 nM to 2.8 microM, indicating that the native enzyme neither dissociated into subunits nor polymerized in this range. The catalytic center activity and the Km values for catechol and dioxygen were 278 s-1, 1.87 and 7.45 microM, respectively, at pH 7.5 and 25 degrees C. The enzyme showed a broad substrate specificity. Among substrates, 4-methylcatechol and 4-chlorocatechol showed specificity constants (approximately 200 microM-1.s-1) higher than that for catechol. Acetone and phenol derivatives competitively inhibited the activity against catechol. The relationship between specific activity and iron content was not linear, suggesting some conformational changes in the partially iron-depleted enzyme.

Amino Acid Sequence↗
PubMed1995

A ColE1-encoded gene directs entry exclusion of the plasmid.

To detect entry exclusion of the ColE1 plasmid, we established an assay system that was not influenced by incompatibility of extant plasmids in the recipient cells or by the viability of the cells due to the killing action of colicin E1 protein. The assay revealed that exc1 and exc2, assigned as genes directing entry exclusion, had no exclusion activity. Instead, mbeD, which had been characterized as a gene for plasmid mobilization, directed the exclusion activity. MbeD was overexpressed and identified as a 35S-labeled protein, which was recovered in both the soluble and membrane fractions, particularly in the inner membrane fraction. An amphipathic helical structure was predicted in the N-terminal region of MbeD as well as in the corresponding homologous proteins of ColA and ColK. These proteins may bind to the inner membrane via the N-terminal amphipathic helix and function in entry exclusion.

Amino Acid Sequence↗
PubMed1995

[Efficacy of smoking cessation instruction for general smokers at an annual physical examination].

A randomized controlled trial was conducted to evaluate the efficacy of smoking cessation instruction given to general smokers at an annual physical examination. Four hundred and twenty-six male and 42 female clients were randomly assigned to an intervention group (I), and 413 males and 76 females were assigned to a control (C) group. The I group was given an approximately 2-minute smoking cessation instruction by physicians, answered a quiz concerning tobacco, chose their own behavioral goals and were handed a leaflet on how to quit smoking. Subjects in both groups responded to a self-administered questionnaire and a 6-month and 12-month follow-up was performed by post card or telephone. The I group received an encouragement card one month after instruction and abstainers of the I group were awarded a telephone card at the 6-month follow-up. The results were as follows: 1) The male I group exhibited 7.3% (6 months), 10.1% (12 months) abstinence rates and the male C group 4.4% (6 months), 5.3% (12 months), respectively. The difference in 12-month abstinence rates was statistically significant. 2) The female I group exhibited abstinence rates of 16.7% (6 months), 23.8% (12 months) and the female C group 14.5% (6 months), 17.1% (12 months), respectively. 3) A multivariate analysis of smoking cessation showed that lower nicotine dependency, strong determination for smoking cessation, and being female were significant factors for abstinence at the 6-month follow-up. At 12 months, the smoking cessation instruction also became a significant factor. These data suggest that a simple smoking cessation instruction at an annual physical examination was effective for general smokers.

Adult↗
PubMed1994

Molecular cloning of a mouse counterpart for human TGF-beta type I receptor.

TGF-beta is a multifunctional polypeptide which is involved in the regulation of cell growth, differentiation, and immunomodulation. Its signaling receptors on the cell surface are postulated to be the type I (TGF beta RI) and type II receptors (TGF beta RII). Previously, TGF beta RII has been cloned and was found to be a receptor type serine/threonine kinase (RSK). In an attempt to isolate novel RSKs expressed in mouse ES cells, we obtained a clone designated as ESK2, which was very closely related to human TGF beta RI. The amino acid sequence of the intracellular domain is completely identical and the transmembrane domain is identical except for one residue. The extracellular domain is 90% homologous with a deletion and an insertion of four amino acid residues. ESK2 also binds to TGF-beta in the presence of TGF beta RII, indicating that ESK2 is the mouse counterpart for human TGF beta RI.

Amino Acid Sequence↗