Analysis of molecular epidemiologic characteristics of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli colonizing feces in hospital patients and community dwellers in a Japanese city.

Infectious diseases caused by extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli are prevalent because of nosocomial infection. In addition, colonization of ESBL-producing E. coli in the intestinal tract of community dwellers due to the contamination of meat or environmental water is assumed to be one of the sources, but the causes have not been clarified. To analyze these factors, we investigated the difference in clonal groups using a combination of phylogenetic groups and multilocus sequence typing of ESBL-producing E. coli, which were obtained from the feces of an inpatient group in our hospital and a community-dwelling group living in a Japanese city. The carriage rate of ESBL-producing E. coli in the inpatient group was 12.5% (32/257), similar to that of 8.5% (42/496) in the community dwellers (P = 0.082). Of the ESBL clonal groups detected from the community dwellers, 52% (22/42) were clonal groups, including D-ST1485, D-ST70, D-ST2847, B2-ST550, B2-ST3510, A-ST93, A-ST580, A-ST716 and B1-ST2787, that have not been detected from human pathogens, meat, companion animals and environmental water, whereas all clonal groups detected from the inpatients were those that had already been reported. The rate of fluoroquinolone-resistant ESBL clonal groups colonizing the intestinal tract of the inpatient group rose as the number of hospital days increased. These results indicated that different factors were related to colonization of ESBL-producing E. coli in the feces of the inpatient group and the community-dwelling group.

Rapid detection of B2-ST131 clonal group of extended-spectrum ß-lactamase-producing Escherichia coli by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry: discovery of a peculiar amino acid substitution in B2-ST131 clonal group.

One reason for the spread of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli worldwide is the global pandemic of the B2-ST131 clonal group. We searched for the specific biomarker peaks to distinguish between the B2-ST131 clonal group and other sequence type (ST) clonal groups isolated from clinical specimens obtained in our hospital. Biomarker peaks at m/z 7650 in the B2-ST131 group (sensitivity of 100% and specificity of 89.7%) and m/z 7707 in the other ST clonal groups showed the highest discrimination abilities. We further verified reproducibility against other Japanese clinical isolates obtained in another area of Japan. Differences between the molecular mass at the 7650m/z and 7707m/z peaks indicated an E34A amino acid substitution by proteomic and genomic analysis. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry rapidly and simply identified the B2-ST131 clonal group in routine examinations and will allow for adequate empirical therapy and the possibility to control both hospital infections and the global pandemic.

Autocrine pathways involving S100A8 and/or S100A9 that are postulated to regulate the immunological functions of macrophages in rats.

The development of ulcerative colitis (UC) is closely associated with abnormally functioning macrophages. Rat S100A8 (r-S100A8) and r-S100A9 (S100 proteins) is abundantly expressed in immune cells of myeloid origin, macrophages; however, it remains unclear why r-S100A9 is dominantly expressed in the macrophages of UC rats (UCR). The purpose of this study was to verify the immunological roles of S100 proteins in UCR. We observed the distribution of S100 protein-positive macrophages in the large colons of UCR using a fluorescent immunological staining method, so that S100 protein-positive macrophages were restricted to the rectal tissues of the UCR, and that the mRNA levels of r-S100A8 and r-S100A9 were up-regulated by stimulation with recombinant rat S100A8 (rr-S100A8) alone and rr-S100A9 alone, respectively. When the changes in the mRNA levels of r-S100A8 and r-S100A9 in macrophages were examined in in vitro study by PCR and real-time PCR, the mRNA levels of anti-inflammatory and inflammatory cytokines increased selectively after stimulation with rr-S100A8 alone and rr-S100A9 alone, respectively. These results suggest that autocrine signal transduction pathways involving S100 proteins regulate the immunological functions of macrophages to maintain homeostasis in the gastrointestinal tract. This may be depended on expression balance of S100 proteins in macrophages. It is strongly suggested that in UCR the immune functions of macrophages are regulated in a complex manner by r-S100A8 and/or r-S100A9 through undefined autocrine pathways on the cells.

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2012].

The nationwide surveillance of antibacterial susceptibility to meropenem (MEPM) and other parenteral antibiotics against clinical isolates during 2012 in Japan was conducted. A total of 2985 strains including 955 strains of Gram-positive bacteria, 1782 strains of Gram-negative bacteria, and 248 strains of anaerobic bacteria obtained from 31 medical institutions were examined. The results were as follows; 1. MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA). 2. Of all species tested, there were no species, which MIC90 of MEPM was more than 4-fold higher than those in our previous studies in 2009 or 2006. Therefore, the tendency to increase in antimicrobial resistance rates was not observed. 3. MEPM resistance against Pseudomonas aeruginosa was 17.8% (56/315 strains). Compared to our previous results, it was the lowest than that in 2006 and 2009. 4. Carbapenem-resistant Klebsiella pneumoniae, and multi-drug-resistant Acinetobacter species, which emerged in worldwide, were not observed. 5. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 6.2% (59/951 strains) in enterobacteriaceae, which increased compared with that of our previous studies in 2009 or before. Whereas, the proportion of metallo-beta-lactamase strains was 1.6% (5/315 strains) in P. aeruginosa, which was stable. In conclusion, the results from this surveillance suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 17 years passed after available for commercial use in Japan.

Role of nitric oxide in the onset of facial nerve palsy by HSV-1 infection.

IMPORTANCE: Although herpes simplex virus type 1 (HSV-1) is a causative agent of Bell palsy, the precise mechanism of the paralysis remains unknown. It is necessary to investigate the pathogenesis and treatment of Bell palsy due to HSV-1 infection. OBJECTIVE: This study elucidated the role of nitric oxide (NO) in the incidence of facial nerve paralysis caused by HSV-1 in mice and to evaluate the possible role of edaravone, a free radical scavenger, in preventing the paralysis. DESIGN, SETTING, PARTICIPANTS: Sixty-two mice served as animal models of Bell palsy in this laboratory study conducted at an academic institution. INTERVENTIONS: Levels of NO in the facial nerve were measured using high-performance liquid chromatography and absorption photometry. The incidence of facial palsy was assessed following administration of edaravone immediately after HSV-1 inoculation and daily for 11 days thereafter. MAIN OUTCOMES AND MEASURES: The ratio of NO (inoculated side to control side) and incidence of facial palsy. RESULTS Before the onset of facial palsy, no substantial difference in the NO level was noted between the HSV-1-inoculated side and the control side. When facial palsy occurred, usually at 7 days after inoculation, the NO level was significantly higher on the inoculated side than on the control side. Following recovery from the palsy, the high NO level of the inoculated side decreased. No increase in the NO level was observed in animals without transient facial palsy. When edaravone was administered, the incidence of facial palsy decreased significantly. CONCLUSIONS AND RELEVANCE: These findings suggest that NO produced by inducible NO synthase in the facial nerve plays an important role in the onset of facial palsy caused by HSV-1 infection, which is considered a causative virus of Bell palsy. Hato and colleagues elucidate the role of nitric oxide in HSV-1­related facial nerve paralysis in mice and evaluate the role of edaravone, a free radical scavenger, in preventing the paralysis.

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2009].

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 2655 strains including 810 strains of Gram-positive bacteria, 1635 strains of Gram-negative bacteria, and 210 strains of anaerobic bacteria obtained from 30 medical institutions during 2009 was examined. The results were as follows; (1) MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multidrug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA). (2) MEPM maintained potent and stable antibacterial activity against Pseudomonas aeruginosa. The proportion of MEPM-resistant strains to ciprofloxacin-resistant strains or imipenem-resistant strains were 53.1% and 58.0% respectively. (3) The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (26 strains) in enterobacteriaceae. And the proportion of metallo-beta-lactamase strains was 2.0% (6 strains) in P. aeruginosa. (4) Of all species tested, there were no species except for Bacteroides fragilis group, which MIC90 of MEPM was more than 4-fold higher than those in our previous study. Therefore, there is almost no significant decrease in susceptibility of clinical isolates to meropenem. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 14 years passed after available for commercial use in Japan.

Valacyclovir and prednisolone treatment for Bell's palsy: a multicenter, randomized, placebo-controlled study.

OBJECTIVE: To investigate the effects of valacyclovir and prednisolone in comparison with those of placebo and prednisolone for the treatment of Bell's palsy, excluding zoster sine herpete. STUDY DESIGN: Prospective, multicenter, randomized placebo-controlled study. SETTING: Six academic tertiary referral centers. PATIENTS: Ultimately, 221 patients with Bell's palsy who were treated within 7 days of the onset. Serological and polymerase chain reaction examinations were performed to distinguish Bell's palsy from zoster sine herpete. INTERVENTION: The patients were treated with either valacyclovir (dosage, 1,000 mg/d for 5 days) plus prednisolone (VP [n = 114]) or placebo plus prednisolone (PP [n = 107]) administered orally. MAIN OUTCOME MEASURE: Recovery from the palsy was defined as a score higher than 36 using Yanagihara 40-point scoring system without facial contracture or synkinesis. The patients were followed up until complete recovery occurred or for more than 6 months in cases with a poor prognosis. RESULTS: The overall rate of patient recovery among those treated with VP (96.5%) was significantly better (p < 0.05) than the rate among those treated with PP (89.7%). The rate of patient recovery was also analyzed by classifying the initial severity of facial palsy. In cases of complete or severe palsy, the rates of patients treated with VP and PP who recovered were 95.7% (n = 92) and 86.6% (n = 82), respectively; the recovery rate for treatment with VP was significantly better than that with PP (p < 0.05). CONCLUSION: The valacyclovir and prednisolone therapy was more effective in treating Bell's palsy, excluding zoster sine herpete, than the conventional prednisolone therapy. To our knowledge, this is the first controlled study of an antiviral agent in the treatment of a sufficient number of Bell's palsy cases based on an etiologic background.

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2006].

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 876 strains of Gram-positive bacteria, 1764 strains of Gram-negative bacteria, and 198 strains of anaerobic bacteria obtained from 30 medical institutions during 2006 was measured. The results were as follows; 1. MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus. 2. As for Pseudomonas aeruginosa, all of the MEPM-resistant strains were resistant to imipenem (IPM). MEPM showed low cross-resistant rate both againt IPM-resistant P. aeruginosa (41.8%) and ciprofloxacin-resistant P. aeruginosa (33.3%). 3. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 4.3% (6 strains) in Escherichia coli, 1.1% (1 strain) in Citrobacter freundii, 21.7% (5 strains) in Citrobacter koseri, 3.1% (4 strains) in Klebsiella pneumoniae, 3.3% (3 strains) in Enterobacter cloacae, 0.8% (1 strain) in Serratia marcescens, and 4.9% (2 strains) in Providencia spp. The proportion of metallo-beta-lactamase strains was 3.1% (10 strains) in P. aeruginosa. 4. Of all species tested, there were no species, which MIC90 of MEPM was more than 4-fold higher than those in our previous study. Therefore, there is almost no significant decrease in susceptibility of clinical isolates to meropenem. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem at present, 11 years after available for commercial use.

A new tool for testing ossicular mobility during middle ear surgery: preliminary report of four cases.

OBJECTIVE: We developed an ossicular vibration tester for the objective and quantitative assessment of ossicular mobility, which is one of the most critical factors affecting postoperative hearing after tympanoplasty. METHODS: Our device consists of three components: a probe shaft with a curved tip to be attached to the target ossicle, a vibration exciter to activate the probe, and a piezoelectric sensor to detect vibrations of the probe. These components are encased in a stainless steel holder, allowing easy hand manipulation during ear surgery. The probe is activated with an electric signal at around 1,600 Hz. The system is controlled with a laptop computer, and the results are presented as the ratio of the ossicular resistance (ROR) to a reference value as a percentage. One measurement takes 10 ms. The device was applied in four selected patients during ear surgery. RESULTS: Several measurements in two of the cochlear implantees showed a greater difference in the RORs of the stapes (15-20% in Case 1 and 35-45% in Case 2), whereas the RORs of the malleus and incus were within the same range. This was thought to correspond to the partial cochlear calcification noted in Case 2. In Case 3, who underwent surgery because of otosclerosis, the ROR of the stapes was high, ranging from 70 to 80%. When measured for the malleus-incus fixation anomaly (Case 4), the ROR of the malleus and incus was in the range of 60 to 70%. Owing to the limited surgical view, the ROR of the stapes could not be measured. No problems related to the measurements with this device were noted. CONCLUSION: The design, principles, measuring procedures, and preliminary results of our new tool for testing ossicular mobility are reported. Measuring the ossicular mobility during surgery may provide important information for deciding the surgical procedures.