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Haruo Watanabe

Publications and source records attributed to Haruo Watanabe.

At least 37 records · Page 2Linked to original sources
PubMed2006

Mechanism of hilA repression by 1,2-propanediol consists of two distinct pathways, one dependent on and the other independent of catabolic production of propionate, in Salmonella enterica serovar Typhimurium.

A glycerol dehydrogenase gene was selected as a multicopy suppressor rescuing the reduced hilA expression in the Salmonella enterica serovar Typhimurium cpxA mutant. A substrate of the enzyme, 1,2-propanediol, repressed hilA expression. The 1,2-propanediol-mediated repression at 150 mM, but not that at 300 mM, was abrogated by blocking the catabolism producing propionate from 1,2-propanediol.

Bacterial Proteins↗
PubMed2006

Surveillance of group B streptococcal toxic shock-like syndrome in nonpregnant adults and characterization of the strains in Japan.

Nine group B streptococci (GBS) strains were isolated from five toxic shock-like syndrome cases of nonpregnant adults in Japan from 2001 to 2005. All of them were identified as Streptococcus agalactiae. The serotypes of these strains were Ib, III, V, and VII. Pulsed-field gel electrophoresis revealed that the patterns of the strains isolated from the different patients were variable. Antimicrobial susceptibility tests showed that all of the strains were susceptible to penicillin G, ampicillin, cefotaxime, clindamycin, and telithromycin. One strain showed intermediate resistance to erythromycin.

Aged↗
PubMed2006

Characteristics of Streptococcus suis isolated from patients in Japan.

Seven cases of Streptococcus suis infection in Japan during 1994 and 2006 were summarized. All cases had porcine exposure and five of them had hand skin injury during the exposure. Five cases presented symptoms of meningitis, three presented symptoms of sepsis, and one resulted in sudden death. All of the isolated S. suis belonged to Lancefield's group D and to serotype 2. They were susceptible to penicillin G, ampicillin, cefotaxime, and ciprofloxacin. However, six of them were resistant to both erythromycin and clindamycin, and four were also resistant to minocycline. Multilocus sequence typing of six isolates showed that they belonged to sequence type (ST) 1, and their pulsed-field gel electrophoresis (PFGE) patterns were similar. The remaining isolate was ST28 and its PFGE pattern was distinct from those of the others.

Animals↗
PubMed2005

A gonococcal homologue of meningococcal gamma-glutamyl transpeptidase gene is a new type of bacterial pseudogene that is transcriptionally active but phenotypically silent.

BACKGROUND: It has been speculated that the gamma-glutamyl transpeptidase (ggt) gene is present only in Neisseria meningitidis and not among related species such as Neisseria gonorrhoeae and Neisseria lactamica, because N. meningitidis is the only bacterium with GGT activity. However, nucleotide sequences highly homologous to the meningococcal ggt gene were found in the genomes of N. gonorrhoeae isolates. RESULTS: The gonococcal homologue (ggt gonococcal homologue; ggh) was analyzed. The nucleotide sequence of the ggh gene was approximately 95% identical to that of the meningococcal ggt gene. An open reading frame in the ggh gene was disrupted by an ochre mutation and frameshift mutations induced by a 7-base deletion, but the amino acid sequences deduced from the artificially corrected ggh nucleotide sequences were approximately 97% identical to that of the meningococcal ggt gene. The analyses of the sequences flanking the ggt and ggh genes revealed that both genes were localized in a common DNA region containing the fbp-ggt (or ggh)-glyA-opcA-dedA-abcZ gene cluster. The expression of the ggh RNA could be detected by dot blot, RT-PCR and primer extension analyses. Moreover, the truncated form of ggh-translational product was also found in some of the gonococcal isolates. CONCLUSION: This study has shown that the gonococcal ggh gene is a pseudogene of the meningococcal ggt gene, which can also be designated as Psiggt. The gonococcal ggh (Psiggt) gene is the first identified bacterial pseudogene that is transcriptionally active but phenotypically silent.

Bacterial Proteins↗
PubMed2005

Effects of activation of central nervous histamine receptors in cardiovascular regulation; studies in H(1) and H(2) receptor gene knockout mice.

To elucidate the central roles of histamine receptors in cardiovascular regulatory system, systolic, mean, and diastolic blood pressures (BPs) and heart rate (HR) were examined in conscious H(1) receptor gene knockout (H(1)KO) mice, H(2) receptor gene knockout (H(2)KO) mice, H(1) and H(2) receptor gene double knockout (DKO) mice, and their respective control mice by the tail-cuff system. Histamine, histamine-trifluoromethyl-toluidine derivative (HTMT, an H(1) agonist), dimaprit (an H(2) agonist), and immepip (an H(3) agonist) were intrathecally administered to these KO mice and control mice. Basal BPs and HR were not different among these three KO mice and their control or wild-type mice. Intrathecal administration of histamine significantly increased BPs and decreased HR in control mice. The increases in BPs were produced by histamine in H(1)KO and H(2)KO mice and by HTMT and dimaprit in C57BL mice. The pressor responses by HTMT and dimaprit in C57BL mice were greater than those by histamine in H(1)KO and H(2)KO mice, although the same decreases in HR were induced by histamine in C57BL and H(1)KO mice and by dimaprit in C57BL mice. The selective stimulation of H(3) receptors by immepip produced a consistent decrease in BPs in control mice. These results obtained with the exogenous selective agonists of three histamine receptors suggest that the pressor responses to histamine are mediated through the stimulation of both H(1) and H(2) receptors, whereas the atropine-sensitive decrease in heart rate is mainly due to H(2) receptors which activate the vagal output to the heart.

Animals↗
PubMed2005

Molecular mechanisms of high level tetracycline-resistance in group A streptococcal isolates, T serotypes 4 and 11.

The molecular mechanism of high level tetracycline resistance in T serotypes 4 and 11 group A streptococcal (GAS) isolates was examined in 61 tetracycline-resistant isolates in Japan. PCR and sequencing analyses revealed that the T serotype/emm genotype, T4/4 isolates carried tet(O) genes, which were genetically homogenous. The T11/11 and T11/89 isolates carried different subtypes of tet(M) genes, which were present on transposons Tn916 and Tn1545, respectively. In addition, these T11 isolates may have obtained the tet(M) gene after the 1990s, because resistance to tetracycline in T11 isolates was rarely found before then. These results strongly suggested that the T4 and T11 GAS isolates acquired tetracycline-resistance via different molecular mechanisms.

Bacterial Proteins↗
PubMed2005

Close correlation of streptococcal DNase B (sdaB) alleles with emm genotypes in Streptococcus pyogenes.

DNase B is a major nuclease and a possible virulence factor in Streptococcus pyogenes. The allelic diversity of streptococcal DNase B (sdaB) gene was investigated in 83 strains with 14 emm genotypes. Of the 15 alleles identified, 11 alleles carried only synonymous nucleotide substitutions. On the other hand, 4 alleles had a non-synonymous substitution other than synonymous substitutions, resulting in the substitution of a single amino acid. The distribution of each allele was generally emm genotype-specific. Only sdaB7 was found in both emm2 and emm4. The promoter region was highly conserved and DNase B protein was similarly expressed in all alleles.

Alleles↗
PubMed2005

Legionella pneumophila serogroup 1 isolates from cooling towers in Japan form a distinct genetic cluster.

Thirty-one epidemiologically unrelated Legionella pneumophila serogroup 1 isolates (10 from cooling towers, 10 from public spas and/or hot spring baths, and 11 from patients) were analyzed by pulsed-field gel electrophoresis (PFGE) and sequence-based typing (SBT) using 6 loci, flaA, pilE, asd, mip, mompS, and proA. The results of PFGE and SBT analysis indicated that all 10 isolates from cooling towers clustered into a unique type, which was distinct from strains of other environmental sources.

Adult↗
PubMed2005

[Comparison of multidrug-resistant Salmonella enterica serovar Newport isolates from a patient and sewages in Fukui Prefecture].

From May 2003 to March 2004, nine strains of multidrug-resistant (MDR) Salmonella enterica serovar Newport were isolated from 5 sewages of 3 sewage treatment plants located in 2 different regions of Fukui Prefecture. Antimicrobial susceptibility testing identified 2 different MDR patterns (type I and II). Type I strains were resistant to ampicillin, tetracycline, streptomycin, chloramphenicol, amoxicillin/clavulanic acid, sulfisoxazole, cefotaxime, cephalothin, ceftriaxone, and ceftrazidime and type II strains were additionally resistant to sulfamethoxazole-trimethoprim and spectionomycin. Neither of kanamycin, fosfomycin, nalidixic acid, gentamycin, or ciprofloxacin resistance was observed. Type I and II strains were different in pulsed-field gel electrophoresis patterns and plasmid profiles, while they showed the same profiles with in each type. All the MDR strains in this study were proved to carry the blaCMY-2 gene by PCR and sequence analyses. Numbers of reports on MDR S. Newport with blaCMY-2 have been increasing in foreign countries such as the United States. The MDR patterns of the isolates in this study were similar to those of the United States. These properties of the type I strains were identical with that a strain isolated from a 7-year-old patient in Fukui Prefecture, in September 2003 which we previously reported. However, the patient lived in a region where no epidemiological associations with the sewage treatment plants were found. This suggests that the MDR strains might prevail in Fukui Prefecture. Domestic surveillance for MDR S. Newport would be need.

Anti-Bacterial Agents↗
PubMed2005

[A case of leptospirosis caused by Leptospira borgpetersenii serovar sejroe infected in Bali Island, Indonesia].

We report a patient with leptospirosis caused by Leptospira borgpetersenii serovar Sejroe infection on Bali Island, Indonesia. This 33-year-old Japanese man had stayed at a resort hotel on the island from July 8 to July 13 2004. At the hotel, he swam in the pool, walked barefoot, and lied down in the grass. He developed a high fever and headache 7 days after completing his trip, and was admitted to our hospital on July 23. On admission he showed conjunctival suffusion and complained of myalgias. Laboratory findings included granulocytosis and elevated CRP. Plasmodium spp. were not found in blood smears, and no pathogenic bacteria were isolated from blood or fecal cultures. We diagnosed the patient as leptospirosis upon detection of slender coiled organisms with characteristic morphology by darkfield examination of blood sample. Minocycline 100 mg i.v.b.i.d. showed excellent efficacy. A microscopic agglutination test (MAT) during the convalescent stage demonstrated a significant increase in antibodies against L. borgpetersenii serovar Sejroe, confirming the diagnosis of leptospirosis. Despite occurrence of a pandemic of leptospirosis in certain Southeast Asian countries including Indonesia, information concerning pandemic disease is limited. In addition serovars of "imported" cases representing infection in pandemic areas differ widely from those in domestic cases. Adequate laboratory support therefore is crucial for accurate diagnosis of leptospirosis.

Adult↗
PubMed2005

[The largest outbreak of legionellosis in Japan associated with spa baths: epidemic curve and environmental investigation].

In July 2002, a large outbreak of legionellosis occurred in a bathhouse with spa facilities in Miyazaki Prefecture. Two hundred-ninety-five patients (including suspected cases) that had pneumonia and/or symptoms of fever, cough and so forth were reported; 37% of them were hospitalized and seven people died. In environmental investigations, Legionella pneumophila serogroups (SGs) land 8, L. dumoffii, L. londiniensis, some other Legionella species and many kinds of amoeba were isolated from 55 samples of bathtub water, tank water, filters and so forth in the spa facilities. The dominant isolates from the bathtab waters belonged to L. londiniensis, L. dumoffii and L. pneumophila SG1, and their maximum concentrations were 1.5 x 10(6), 5.2 x 10(5) and 1.6 x 10(5) cfu/100 mL, respectively. L. pneumophila SG1 strains isolated from bathtub water, tank water, filters and sputa of patients showed a indistinguishable DNA fingerprint pattern by pulsed-field gel electrophoresis (PFGE), confirming that the source of infection was the spa water. Our study indicate that spas may be a significant health hazard if hygienic management fails.

Adolescent↗
PubMed2005

[Isolation of Neisseria meningitidis from healthy persons in Japan].

Between September 2000 and March 2003 healthy subjects in 10 prefectures of Japan were investigated to identify carriers of Neisseria meningitidis. Twenty-five N. meningitidis strains were isolated from 5886 throat swab specimens collected from healthy persons, such as students, elderly, and foreigners. Of the 25 carriers, 9 were teenagers, 15 were in their twenties, and only one was in the fifties. The male-female ratio of the carriers was 17 to 8, showing male dominance. The serogroups of the 25 strains were B (9 strains), Y (4 strains) and non-groupable (12 strains). One of the strains was found to be deficient in gamma-glutamyl aminopeptidase activity, which is an identification marker for N. meningitidis.

Adolescent↗
PubMed2005

[Symptoms of food-borne diseases and gastroenteritis in Kyushu, Japan].

In this study we analyzed the symptoms of gastroenteritis or food-borne disease caused by the 10 most prevalent pathogens: Norovirus, Salmonella, Vibrio parahaemolyticus, Campylobacter jejuni, Clostridium perfringens, Shiga toxin-producing Escherichia coli (STEC), enterotoxigenic E. coli (ETEC), Shigella sonnei/flexneri (Shigella), Staphylococcus aureus, and emetic-type Bacillus cereus. The symptoms diarrhea, vomiting, fever, abdominal pain, and headache, and the incubation period in 646 cases in 10 districts of Kyushu between January 2000 and December 2004 were recorded. The pathogen with the shortest mean incubation period was B. cereus (0.8 h), and was followed by S. aureus (3.3 h), C. perfringens (10.7 h) and V. parahaemolyticus (16.4 h). All the patients infected with B. cereus and S. aureus developed symptoms within 6 hours, and those infected with V. parahaemolyticus and C. perfringens developed symptoms within 24 hours. Bloody diarrhea was associated with STEC and Shigella, but rare with other pathogens. Vomiting was associated with almost all cases of S. aureus and B. cereus infection, and occurred in 71.5% of the Norovirus cases and 56.1% of the V. parahaemolyticus cases. Vomiting was less common in the C. perfringens (22.0%) and the ETEC and STEC (both about 5%). Bloody diarrhea, abdominal pain, and vomiting were statistically significantly more common with STEC 0157 infection than with STEC non-0157 infection. Since the cases analyzed in this study included all degrees of illness, mild to severe, and a wide range of ages, the information obtained will serve as a good reference material for administrative and laboratory work when an outbreak takes place.

Abdominal Pain↗
PubMed2005

Antimicrobial susceptibility survey of Streptococcus pyogenes isolated in Japan from patients with severe invasive group A streptococcal infections.

We assessed antimicrobial susceptibility against 211 Streptococcus pyogenes strains isolated from patients with severe invasive group A streptococcal infections. Overall, 3.8, 1.4, 1.4, and 0.5% of the isolates were resistant to erythromycin, clindamycin, telithromycin, and ciprofloxacin, respectively, and 10.4% had intermediate resistance to ciprofloxacin. All isolates were susceptible to ampicillin and cefotaxime.

Anti-Bacterial Agents↗
PubMed2005

Antimicrobial susceptibility of Shigella sonnei isolates in Japan and molecular analysis of S. sonnei isolates with reduced susceptibility to fluoroquinolones.

We performed susceptibility testing with Shigella sonnei isolates from imported and domestic cases of infection in Japan during 2001 and 2002. Some S. sonnei isolates were resistant to nalidixic acid, tetracycline, and trimethoprim-sulfamethoxazole. Most of the nalidixic acid-resistant strains showed reduced susceptibility to fluoroquinolones but did not show fluoroquinolone resistance.

Drug Resistance, Bacterial↗