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Key Clinical Message A 76-year-old Japanese woman contracted a Mycobacterium tuberculosis (TB, Manila type) infection in Japan, despite never having traveled. However, her son was treated for TB in the Philippines 3 years before he stayed at her house. Spoligotyping allows us to identify the TB genotype and identify the route of infection.

Acute otitis media (AOM) is the most common upper respiratory tract infection in childhood. Children with AOM were enrolled at Tohoku Rosai Hospital between July 2006 and June 2011 if their middle ear fluid cultures after tympanocentesis yielded only Haemophilus influenzae . The susceptibilities of the isolates to ampicillin were determined, and microtiter biofilm assays and invasion assays using BEAS-2B cells were performed. The association between these bacterial characteristics and clinical relapses of AOM and treatment failures was evaluated. Seventy-four children (39 boys and 35 girls) with a median age of 1 year (interquartile range [IQR], 0.25 to 2 years) were enrolled. Among 74 H. influenzae isolates, 37 showed intermediate resistance or resistance to ampicillin (MIC, ≥2 μg/ml). In the microtiter biofilm assay, the median optical density at 600 nm (OD 600 ) was 0.68 (IQR, 0.24 to 1.02), and 70 isolates formed biofilms. The median invasion rate was 15% (IQR, 0 to 10%), and 46 isolates invaded BEAS-2B cells. Relapses and treatment failures occurred in 19 and 6 children, respectively. There was no significant difference in the invasion rates between patients with and those without relapses or treatment failures. Also, there was no significant association between biofilm formation and relapse or treatment failure. The improvements in the severity scores after 1 week were significantly associated with the recovery time ( P < 0.0001). We did not identify any significant association between relapse or treatment failure and bacterial factors. AOM has a multifactorial etiology, and this may explain why we could not find a significant association. An improvement in the severity score after 1 week of treatment may be a useful predictor of the outcome of AOM.

Actinomycosis of the middle ear and mastoid is extremely rare. Here, we report a unique case of actinomycosis of the middle ear and mastoid caused by Actinomyces meyeri diagnosed by 16S rRNA gene sequence analysis.

Background Natural catastrophes increase infectious disease morbidity rates. On March 11, 2011, a 9.0-magnitude earthquake and associated Pacific coast tsunami struck East Japan. The aim of this study was to investigate the characteristics of patients with infectious diseases who needed hospitalization after this disaster. Methods We searched the medical records of 1,577 patients admitted to Tohoku University Hospital in the Sendai area within 1 month (March 11, 2011-April 11, 2011) after the disaster. We examined (1) changes in the rates of hospitalizations for infectious diseases over time and (2) the variety of infectious diseases. Results The number of hospitalized patients with infectious diseases increased after the first week to double that during the same period in 2010. Pneumonia comprised 43% of cases, and 12% consisted of skin and subcutaneous tissue infection, including tetanus. Pneumonia was prevalent in elderly patients (median age, 78 years) with low levels of serum albumin and comorbid conditions, including brain and nervous system disorders. Sputum cultures contained Streptococcus pneumoniae, Moraxella catarrhalis , and Haemophilus influenzae , known pathogens of community-acquired pneumonia in Japan. In addition, 20.5% of patients had positive results for urinary pneumococcal antigen. Conclusions Among hospitalized patients, infectious diseases were significantly increased after the disaster compared with the same period in 2010, with pneumonia being prominent. The analyses suggest that taking appropriate measures for infectious diseases, including pneumonia, may be useful for disaster preparedness and medical response in the future.

In 1968, the Japanese Society of Chemotherapy (JSC) established an agar dilution method for MIC determinations of aerobic bacteria [1]. In 1979, the JSC established an agar dilution method for MIC determinations of anaerobic bacteria. Furthermore, a revision of the agar dilution standard was made in 1980, and this served as the standard method for MIC determinations for an extensive period of time in Japan. In 1990, the committee established a standard microbroth dilution method for MIC determinations. This method was modified in 1992 for fastidious aerobic and anaerobic bacteria [2]. In the development of standards for antimicrobial susceptibility testing, there has been a movement to incorporate pharmacologic as well as clinical considerations with respect to in vitro antimicrobial susceptibility interpretations. This trend reflects the need to respond to the emergence and spread of resistant microorganisms as well as a greater understanding of pharmacokinetics and pharmacodynamics and how it relates to improved patient outcome. The Clinical Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility (EUCAST) are among the professional organizations that proactively revise antimicrobial susceptibility testing on a regular basis. JSC has also been revising its standards. In 2007, the agar dilution method was revised. After the exclusion of selected organisms from the CLSI agar dilution standard, this method was adopted by the JSC [3]. With respect to revising the standard method for microbroth dilution antimicrobial susceptibility testing, a committee chaired by Keizo Yamaguchi was formed in January 2008. The subcommittee’s first task was to critically examine the methods for the antimicrobial susceptibility testing of Haemophilus influenzae. Although JSC and CLSI microbroth dilution methods both use a Mueller– Hinton base, the supplements differ. This difference had raised concerns among some Japanese clinical microbiology professionals that there were many issues with the CLSI method with respect to reported difficulties in measuring endpoints and the poor growth of some strains. Our first action was to send questionnaires to the members of the JSC and the Japanese Society for Clinical Microbiology to better understand the technical problems experienced in clinical microbiology laboratories regarding microbroth dilution testing of H. influenzae. From the responses to the questionnaire, it was clear that a major problem in routine testing was the poor growth of Members of the Microdilution Susceptibility Standards Committee: committee chairperson: Keizo Yamaguchi, committee members: Yoichi Hirakata, Intetsu Kobayashi, Masanari Ikedo, Akira Ohno.

Acinetobacter, which is Gram-negative non-fermentated bacilli, is isolated from natural environment and human body, including skin and gastrointestional tracts of both healthy persons and immunocompromised patients. Acinetobacter can cause bacterial infections, such as blood stream infections and health care-associated pneumonia. The definition of multi-drug resistant (MDR) of Acinetobacter has not been internationally harmonized, however, it is defined when MICs of imipenem, amikacin and ciprofloxacin are 16 microg/ml, 32 microg/ml and 4 microg/ml or higher, respectively, in Japan. Recently, only a few outbreaks by Acinetobacter have been reported in Japan, while outbreaks by Acinetobacter are more common in Western and Asian countries abroad. We should pay attention and caution on outbreaks by Acinetobacter and spread of drug-resistant Acinetobacter as much as we can.

Background Refugees and displaced populations after natural disasters have been vulnerable to tuberculosis. We report an active pulmonary tuberculosis case at a shelter and the subsequent contact investigation and review lessons learned from the 2011 Great East Japan Earthquake. Methods The contact investigation was conducted to identify latent tuberculosis infection among a total of 95 contact persons, including 78 evacuees at the shelter, who were exposed to the index tuberculosis patient. The association between exposure time of contacts to a patient with active tuberculosis and results of interferon-γ release assay (IGRA) was also examined. Results IGRA was positive in 9 (12.3%) of 73 evacuees at the shelter. Contacts who were exposed to active tuberculosis for more than 25 days were significantly more likely to be IGRA positive, compared with contacts exposed for less than 20 days. All of the 4 evacuees with latent tuberculosis infection who initiated treatment completed the regimen successfully. Conclusion When a disaster strikes and many people are living in shelters, it is essential for health care personnel to first suspect tuberculosis and implement prevention and control in collaboration with referral hospitals and public health centers.

Invariant NK T (iNKT) cells are known to play a critical role in the regulation of inflammatory responses in various clinical settings. In the present study, we assessed the contribution of iNKT cells to the development of acute lung injury (ALI), which was caused by intra-tracheal administration of LPS. Jα18 gene-disrupted mice lacking these cells underwent neutrophilic inflammatory responses in lungs at an equivalent level as control mice. Next, mice were sensitized intra-tracheally with α-galactosylceramide, an activator of iNKT cells, followed by challenge with LPS. In this model, mice showed severe lung injury, and all mice were killed within 72 h after LPS injection. IFN-γ and tumor necrosis factor (TNF)-α were strikingly elevated in the lungs of these mice. Administration of neutralizing mAb against IFN-γ and TNF-α attenuated lung injury in a histopathological analysis and improved their survival rate. Flow cytometric analysis revealed that IFN-γ was expressed in NK cells, iNKT cells and also Gr-1(dull+)Ly-6C(+) monocytes and TNF-α was detected mainly in Gr-1(bright+)Ly-6G(+) neutrophils and Gr-1(dull+)Ly-6C(+) monocytes. Otherwise, in mice treated with LPS alone, IFN-γ was not detected in the lungs and Gr-1(bright+)Ly-6G(+) neutrophil was a main cellular source of TNF-α production. Anti-Gr-1 mAb resulted in the attenuation of ALI and decrease in the level of these cytokines. These results indicated that activation of iNKT cells led to striking exacerbation of ALI caused by LPS and that Gr-1(+) monocytes were recruited in the lungs with expressing IFN-γ and TNF-α and played an important role in the development of these responses.

Objectives: Streptococcus pyogenes causes various diseases in humans. While the prevalence of fluoroquinolone-resistant S. pyogenes isolates has been increasing since 2000 in the USA and Europe, it has remained very low in Japan. We isolated a fluoroquinolone-resistant S. pyogenes strain and analysed its genetics. Methods: TU-296, a strain of S. pyogenes resistant to levofloxacin (MIC 16 mg/L), was isolated from the throat of a patient in their thirties with pharyngitis in autumn 2007. We carried out susceptibility tests for various anti-microbial agents and PCR analysis of the genes gyrA, gyrB, parC and parE in the quinolone resistance-determining region, followed by sequencing of the PCR products to find mutation(s) and the resulting amino acid substitution(s). We then sequenced the PCR product of the emm gene and determined the emm genotype. Results: S. pyogenes TU-296 was found to have the following mutations and amino acid substitutions: adenine 476 to cytosine in gyrA and cytosine 367 to thymine in parC, resulting in Glu-85→Ala in GyrA and Ser-79→Phe in ParC. The genotype of the isolate was emm11. Conclusions: Amino acid substitutions in fluoroquinolone-resistant S. pyogenes have already been reported from Europe and the USA, including Ser-81→Phe or Tyr and Met-99→Leu in GyrA, as well as Ser-79→Phe, Tyr or Ala and others in ParC. Numerous point mutations were found in parC and parE of S. pyogenes TU-296. In addition, a new amino acid substitution was detected (Glu-85→Ala in GyrA). To our knowledge, there have been no previous reports of this substitution in a clinical isolate of S. pyogenes.

In this study, we elucidated the role of tumor necrosis factor (TNF)-alpha in the host defense to pulmonary infection with Streptococcus pneumoniae and defined the cellular source of this cytokine at an early stage of infection. Administration of anti-TNF-alpha monoclonal antibody (mAb) resulted in the reduced accumulation of neutrophils in bronchoalveolar lavage fluids (BALFs) and severe exacerbation of this infection. In a flow cytometric analysis, the intracellular expression of TNF-alpha was detected in Gr-1(bright+) and Gr-1(dull+) cells during the time intervals postinfection, and F4/80(+) cells expressed intracellular TNF-alpha before Gr-1(dull+) cells appeared. The Gr-1(bright+) and Gr-1(dull+) cells sorted from BALF cells at 24 h were identified as neutrophils and macrophage-like cells, respectively, and the Gr-1(dull+) cells expressing CD11c, partially CD11b and a marginal level of F4/80 secreted TNF-alpha in in vitro cultures. Finally, deletion of Gr-1(+) cells by administration of the specific mAb significantly reduced the concentrations of this cytokine in BALF at 6 and 12 h postinfection, but not the expression of TNF-alpha in F4/80(+) cells. Thus, these results demonstrated that neutrophils, F4/80(+) macrophages and Gr-1(dull+) CD11c(+) macrophage-like cells played an important role in the production of TNF-alpha in lungs at an early stage of infection with S. pneumoniae.

In the autumn two patients with general malaise were consecutively admitted to the department of internal medicine of our hospital in the northern region of Nagasaki Prefecture. Since both patients were engaged in rice farm work and showed conjunctival suffusion and pain of the gastrocnemius muscle, leptospirosis was suspected. The first patient required temporary hemodialysis for renal dysfunction, whereas liver dysfunction developed in the second patient. The disease was remitted by antimicrobial agents. A diagnosis of leptospiro sis was made serologically in both patients. Leptospirosis should be considered as a differential diagnosis when a patient engaged in farm work in the autumn has typical symptoms, and an early initiation of treatment after onset is important., Internal Medicine, 49(12), pp.1143-1147; 2010

Pseudomonas (P.) aeruginosa is a major opportunistic pathogen especially in immunocompromised patients. To evaluate the invasiveness of respiratory pathogens, we developed monolayer culture systems and examined the degree of invasion by P. aeruginosa and invasive Salmonella (S.) typhimurium strains using human respiratory cell lines: A549 (derived from lung cancer), BEAS-2B (normal bronchial epithelium), and Calu-3 (pleural effusion of a patient with adenocarcinoma of the lung). Cells were seeded into filter units containing 0.33 cm(2) filter membranes with 3.0 microm pores, and were incubated at 37 degrees C under 5% CO(2) for 4-10 days. By monitoring the trans-monolayer electrical resistance (TER), we judged that BEAS-2B cells (TER values: 436.2 +/- 16.8 to 628.8 +/- 66.3 Omega cm(2)) and Calu-3 cells (TER values: 490.5 +/- 25.2 to 547.8 +/- 21.6 Omega cm(2)) formed monolayers with tight junctions, but not A549 cells. On day 8 of culture, monolayer cultures were infected with bacteria, and the number of microorganisms penetrating into the basolateral medium was counted. Wild-type P. aeruginosa PAO1 (PAO1 WT) and S. typhimurium SL1344 were detected in the basolateral medium of BEAS-2B monolayer system by 3 h after inoculation, while only P. aeruginosa PAO1 WT was detected in the basolateral medium of Calu-3 monolayer, indicating poor invasiveness of S. typhimurium SL1344 in the Calu-3 system. These findings suggest that BEAS-2B or Calu-3 monolayer system could be useful for evaluating the invasiveness of respiratory pathogens. Because of the difference in bacterial invasiveness, we may need to choose a suitable cell system for each target pathogen.

Methicillin resistant Staphylococcus aureus (MRSA) is exceptionally critical to infection treatment and control in the health-care setting. MRSA has been detected at high levels in Japan, and the frequency of MRSA infection must be ascertained to provide a baseline with which to assess various infection control efforts. We studied MRSA infection rate at a general hospital in Japan in all 65,135 inpatients of Sendai Kousei Hospital from January 2004 to December 2008. MRSA’s prevalence among strains of S. aureus and the rate of MRSA detection were studied. Identification of MRSA infection is according to the laboratory-based ward liaison surveillance. The minimal inhibitory concentrations (MICs) of vancomycin, teicoplanin, and arbekacin for the various isolates were determined. During the period studied, there were 621 MRSA-positive patients. MRSA prevalence among strains of S. aureus was 45.5% (621/1,365). The rate of MRSA detection in inpatients was 0.953/100 inpatients. Of the 621 patients from whom MRSA was isolated, 51 (8.2%) had an MRSA infection (MRSA infection rate 0.078/100 inpatients). MRSA was often detected from the respiratory tract, but this seldom led to infection, since many of those affected were merely carriers. MICs against MRSA was 0.5–4 μg/ml for vancomycin, 0.5–16 μg/ml for teicoplanin, and 0.5 to >16 μg/ml for arbekacin, with no tendency for tolerance observed for these drugs. Findings suggest that whereas MRSA remains prevalent, there is a low incidence of infection in a general hospital in Japan.

Efflux systems are thought to contribute to antimicrobial resistance in Pseudomonas aeruginosa. The mexAB-oprM deletion strain of P. aeruginosa PAO1 is compromised in its capacity to invade Madin-Darby canine kidney (MDCK) cells, suggesting that P. aeruginosa exports invasion determinants using a MexAB-OprM system. The influences of efflux pump inhibitors (EPIs), including the broad-spectrum EPI Phe-Arg-beta-naphthylamide (PAbetaN) and MexAB-OprM-specific EPI D13-9001, on the invasion of wild-type (WT) P. aeruginosa PAO1 and its MexAB-OprM-overproducing nalB strain were examined. The invasiveness of PAO1 WT and nalB strains was inhibited in the presence of EPIs in a concentration-dependent manner. Reduction of the invasiveness of both strains was greater for D13-9001 compared with PAbetaN. EPIs are thought to be useful in reducing the invasiveness and antimicrobial resistance of P. aeruginosa and thus may be promising as new anti-infectious agents.

β-Lactamase-negative ampicillin-resistant (BLNAR) isolates of Haemophilus influenza e have been emerging in some countries, including Japan. The Clinical and Laboratory Standards Institute has only a susceptible MIC breakpoint (≤1 μg/ml) for piperacillin-tazobactam and a disclaimer comment that BLNAR H. influenzae should be considered resistant, which was adapted without presentation of data. In addition, fluoroquinolone-resistant H. influenzae isolates have recently been occasionally reported worldwide. To address these problems, we examined susceptibilities to β-lactams, including piperacillin-tazobactam, and ciprofloxacin by microdilution and disk diffusion (only for piperacillin-tazobactam) methods, against a total of 400 recent H. influenzae clinical isolates, including 100 β-lactamase-negative ampicillin-susceptible, β-lactamase-positive ampicillin-resistant, BLNAR, and β-lactamase-positive amoxicillin-clavulanate-resistant (BLPACR) isolates each. BLNAR and BLPACR isolates were tested by PCR using primers that amplify specific regions of the ftsI gene. We also detected mutations in quinolone resistance-determining regions (QRDRs) by direct sequencing of the PCR products of DNA fragments. Among β-lactams, piperacillin-tazobactam exhibited potent activity against all isolates of H. influenzae , with all MICs at ≤0.5 μg/ml (susceptible). A disk diffusion breakpoint for piperacillin-tazobactam of ≥21 mm is proposed. We confirmed that all BLNAR and BLPACR isolates had amino acid substitutions in the ftsI gene and that the major pattern was group III-like (87.5%). One ciprofloxacin-resistant isolate (MIC, 16 μg/ml) and 31 ciprofloxacin-susceptible isolates (MICs, 0.06 to 0.5 μg/ml) had amino acid changes in their QRDRs. Piperacillin-tazobactam was the most potent β-lactam tested against all classes of H. influenzae isolates. It is possible that fluoroquinolone-resistant H. influenzae will emerge since several clinical isolates carried mutations in their QRDRs.

Susceptibility to a range of antimicrobial agents was determined among isolates of Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae collected in 12 centers throughout Japan during years 1-5 (the respiratory seasons of 1999-2004) of the longitudinal Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin study. The most frequent source of isolates of S. pneumoniae was from patients with community-acquired pneumonia (CAP) (25.3%). Reduced susceptibility to penicillin or erythromycin resistance was common among S. pneumoniae isolates (30.9-44.5% and 77.2-81.9%, respectively). The macrolide MIC(50) for S. pneumoniae wasor=128 microg/ml (azithromycin and erythromycin) andor=64 microg/ml (clarithromycin). The erm(B) genotype accounted for the most erythromycin-resistant isolates in each study year. H. influenzae isolates were most commonly derived from patients with CAP (26.2%). The proportion of H. influenzae isolates that were beta-lactamase positive ranged between 4.3% and 9.7%. The prevalence of beta-lactamase-negative ampicillin-resistant isolates increased from 0.4% to 2.6% between years 1 and 4 then to 19.7% in year 5. S. pyogenes isolates were highly susceptible to most antimicrobial agents except macrolides and tetracycline. Telithromycin was highly active against all three pathogens examined throughout the study.

We report two consecutive cases of staphylococcal scalded skin syndrome (SSSS) in our neonatal intensive care unit (NICU). Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from skin swabs. An epidemiological survey conducted on the NICU staff, isolated MRSA from nasal swabs of three personnel. Gene analysis of these five isolates using pulsed-field gel electrophoresis (PFGE) of the bacterial genome and polymerase chain reaction (PCR) for a panel of toxin genes encoded two patient-derived isolates of exfoliative toxin B (ETB) considered to be identical based on the spectrum of toxin genes encoded and PFGE patterns. Three staff-derived isolates did not, however, encode ETB and showed different repertoires of toxin genes and PFGE patterns from those of the two patient-derived isolates. Nasal application of mupirocin to all carriers successfully eradicated MRSA. Horizontal transmission of ETB-producing MRSA between the two patients in the NICU was confirmed, but no NICU personnel carried the same isolate. We therefore wish to emphasize the importance of strict standard and contact precautionary measures and the monitoring of MRSA in the NICU, together with the usefulness of gene analysis using PFGE and PCR as epidemiological tools.

Objective To determine the differences in the clinical features of bacterial pneumonia patients between patients co-infected with influenza virus or not co-infected. Methods Fifteen adult patients with bacterial pneumonia (7 men and 8 women) who also tested positive for influenza virus antigen were compared with those with bacterial pneumonia alone (n=28). Results Complications with chronic lung diseases were more frequently found in bacterial pneumonia patients with influenza virus infection, compared with those who had bacteria pneumonia alone. Statistical differences were also found in body temperature, and heart rates between the two groups. CRP levels, chest X-ray infiltrates and the severity of pneumonia, as determined using the criteria of the Japan Respiratory Society (JRS) and/or the Infectious Diseases Society of America (IDSA), were also significantly worse in patients of bacterial pneumonia infected with influenza virus, than in those who had bacterial pneumonia alone. Conclusions The severity of pneumonia in patients co-infected with influenza virus and bacteria was significantly higher than in those infected with bacteria alone. These data suggested that the influenza virus infection enhanced the bacterial pneumonia. Further study of the pathogenesis of the synergic interaction between influenza virus and bacteria is warranted., Internal Medicine, vol.46(13), pp.953-958; 2007

Implant-related infection after orthopedic surgery is difficult to cure. One of the causes of infection is the bacterial biofilm that forms around biomaterials used during surgery. Therefore, it is necessary to investigate bacterial biofilms extensively to resolve the problems of these postoperative infections. However, no established culture method or quantification system exists for bacterial biofilms grown on the surface of the metallic biomaterials used in orthopedics, which are nonradiolucent. The purpose of this study was to develop a quantitative method to evaluate the difference in resistance of stainless steel versus titanium to staphylococcal biofilms and the efficacy of antibiotics against biofilms.The bacterial strains used in this study were three Staphylococcus aureus stains: strain Seattle 1945 and two clinical strains cultured from postoperative infections. Staphylococcal biofilms were formed on stainless steel washers (SUS304) and titanium washers (pure titanium). They were stained with crystal violet and were examined with a digital microscope to calculate the bacterial coverage rate (BCR) by NIH imaging.The BCR of S. aureus biofilms formed on stainless steel and titanium washers increased over time. At 24, 48, and 72 h after cultivation, the amount of biofilm on the surface of the stainless steel washers was significantly greater or tended to be greater than that on the titanium. Cefazolin was applied to the obtained biofilms of two clinically isolated S. aureus strains. Cefazolin did not eradicate the biofilms but significantly reduced the biofilm of one strain.The newly developed quantitative method (static microtube culture and measurement system) was useful for assessing the amount of bacterial biofilms on the surface of nontranslucent biomaterial. We found that titanium may be more resistant to bacterial infection than stainless steel. To control implant-related severe infections, the biomaterials should be assessed from the viewpoint of their resistibility to bacterial adhesions and infections.

An excessive amount of neutrophil elastase (NE) released from neutrophils accumulated in the lung can cause tissue damage, despite its importance to host defense against microbial pathogens in severe pneumonia. Therefore, NE inhibitors may reduce tissue damage in lungs with severe pneumonia. In this study, the efficacy of a specific NE inhibitor, sivelestat sodium hydrate (sivelestat), was examined using a murine model of severe pneumonia with Streptococcus pneumoniae. Male mice (CBA/JNCrj, aged 5 weeks) were inoculated intranasally with penicillin-susceptible S. pneumonia (1.0 x 10(5) CFU/mouse). Sivelestat (3 mg/kg) or physiological saline was administered every 12 hours beginning at 12 hours after inoculation. Survival was primarily evaluated. Bronchoalveolar lavage fluid (BALF) and blood were collected at 30 hours after inoculation. Thus, cell counts in BALF and numbers of viable bacteria in blood were determined. Histopathological analysis was also performed. Sivelestat significantly prolonged survival when compared with the control group (P < .05), although all animals died within 4 days. Cell count and histopathological analysis indicated that sivelestat prevented the progression of lung inflammation, such as alveolar neutrophil infiltration and hemorrhage. Furthermore, the number of viable bacteria in blood was significantly lower in the sivelestat group than in the control group (5.69 +/- 0.27 and 6.75 +/- 0.32 log CFU/mL, respectively; mean +/- SEM, P < .01). Sivelestat prolonged survival in this model. A possible explanation for the improved survival is that sivelestat prevents tissue damage by inhibiting NE activity in the lung. Therefore, NE inhibitors may be useful for treating with patients with severe pneumonia.

A 77 years old woman who had a bite with eschar on her left arm, was admitted to emergency ward in our hospital, because of high fever, severe malaise, skin eruption, and consciousness disturbance beginning 5 days previously. She was diagnosed as Japanese spotted fever by seropositive of Rickettsia japonica (R. japonica) antibody, and successfully treated with fluoroquinolone, after minocycline hydrochloride had been proven ineffective. R. japonica-specific DNA was detected by PCR from the tick: Haemaphysalis hystricis larvae collected from a mountainous location in Fukuoka, Japan where the patient had been bitten., Internal Medicine, vol.45(22), pp.1323-1326; 2006

We developed a real-time PCR assay combined with melting curve analysis for rapidly genotyping quinolone resistance-determining regions (QRDR) of topoisomerase genes in Streptococcus pneumoniae. This assay was not only accurate for the screening of fluoroquinolone (FQ) resistance but also relevant as an early warning system for detecting preexisting single QRDR mutations., Journal of clinical microbiology, 44(12), pp.4553-4558; 2006

The K-ras oncogene is one of the most useful genetic markers in screening for the presence of cancers because it is largely involved in tumorigenesis. However, most mutationdetection techniques are generally unsuitable for routine use, especially due to their timeconsuming, labor-intensive, and sensitive natures. Accordingly, we attempted to establish a new technique for analysis of K-ras alterations at codons 12 and 13 from body fluid specimens with tumor DNA using realtime polymerase chain reaction (PCR) with melting curve analysis (MCA). In this PCRMCA method, K-ras was easily genotyped by melting temperatures (Tm) that differ by 3.6°C to 11.6°C with an acceptable reproducibility of Tm. The shape of the melting curve gave easier interpretation. The detection sensitivity was at least 10 -3 . The entire process of the test was completed within 4 hours, saving 7 to 8 hours when compared to the current PCR-restriction fragment length polymorphism (RFLP) analysis. The examination of the MCA method using 38 clinical samples revealed the better detection rate (32% versus 24%) and diagnostic efficiency (100% versus 92%) compared with that of the PCR-RFLP. In conclusion, this small scale but high throughput method is acceptable for clinical use to analyze K-ras alterations from body fluids and plasma DNA, including small tumor DNA.

Based on statistical analysis of its age-dependent occurrence, a multi-step carcinogenesis model has been proposed for Adult T-cell Leukemia/Lymphoma (ATLL). We have previously reported that the deletion of the p16 gene is a key event in ATLL progression. In the current study, we report for the first time that the aberrations of p16 and p53 are mutually exclusive in ATLL and either of the two events is sufficient for the ATLL progression. More than half of the patients had one of the two aberrations, and both aberrations emerged as significant markers for a poor prognosis.

Nocardia is typically regarded as an opportunistic infection, with pulmonary nocardiosis frequently disseminated to organs hematogenous by, and nearly half of these cases resulting in complicated nocardia brain abscess. Disseminated nocardia has a dismal prognosis with high mortality, and should be checked for multiple organs including the brain when nocardiosis is diagnosed. We describe the successful treatment of nocardia brain abscesses in an immunocompetent older people with pneumoconiosis by combining trimethoprim-sulfamethoxazole and ciprofloxacin. Patients had no history of fever, headache, or respiratory symptoms such as cough, or sputum until the acute hemiplegia episode. Nocardia infection is not as rare as generally assumed and should be considered as a possibility in the elderly due to its high mortality.

A 76-year-old man admitted for general malaise with fever was found in clinical examination on admission to have eosinophilic pleural effusion, peripheral eosinophilia, and a slightly elevated inflammatory reaction. Immunological examination, including microplate ELISA, showed a high titer of specific antibody against Toxocara canis in both the serum and pleural effusion. We started treatment using albendazole, and found inflammatory findings and serum IgE were ameliorated. Parasitic disease is an important consideration in the differential diagnosis of eosinophilic pleural effusion, and serology is useful in screening for this.

The BD Phoenix Automated Microbiology System SMIC/ID panel was evaluated for identification and antimicrobial susceptibility testing (AST) of various streptococci. A group of 97 consecutive clinical isolates of Streptococcus pneumoniae , 23 Streptococcus pyogenes , 24 Streptococcus agalactiae , and 34 viridans streptococci were collected and comparisons made with routine manual methods used in the clinical microbiology laboratory. Overall, in 162 (91%) of 178 isolates, Phoenix identification results demonstrated agreement. For AST results for the 162 isolates that demonstrated identification concordance, the overall essential agreement rate was 98.5%; the category agreement was 94.9%; and the very major error, major error, and minor error rates were 0%, 0.15%, and 5.8%, respectively. Although relatively high minor error rates were observed with S. pneumoniae and β-lactams, 79.2% of the 77 minor errors were the result of a single log 2 dilution difference. The Phoenix SMIC/ID panel performed favorably and demonstrated the advantages of automation and simple methodology.

Human herpes virus (HHV) is well known to reactivate in immunocompromised situations and plays an immunomodulatory role leading to indirect effects through viral replication to the host. The aim of this study was to determine the laboratory and clinical relevance of a comprehensive PCR-based assay for detecting eight HHVs, which are lymphotropic and cause disease in humans. Using 176 samples collected from 146 specimens of peripheral blood, 12 skin nodules, 11 lymph nodes and 7 others of patients who were suspected to have adult T cell leukemia (ATL), the PCR-based assay was validated to simultaneously detect one or more herpes viral DNA with two consensus primer sets. Although most samples were seropositive for either of the HHVs, only 50% of them were positive for either herpes viral DNA with EBV in 76%, HHV-6 in 14% and VZV in 9%. Furthermore, such a herpes viral DNA positive status was not always associated with clinical symptoms relating to the virus, implying active replication in the blood cells, but being asymptomatic. HHV-8 viral DNA, although Kaposi's sarcoma has been reported to be complicated with ATL, was not demonstrable. HHV-6B was detected only in HTLV-1 healthy carriers and ATL patients, and may imply a co-factor role with HTLV-1. This PCR-based assay provides a herpes viral infectious status compensatory for virus-serology and is a clinically relevant laboratory test, serving as a screening marker for active infection.

Human T-cell leukemia virus type-1 (HTLV-1) is the etiological agent of adult T-cell leukemia (ATL), and leukemic cells always carry the proviral genome monoclonally integrated into their host genomes at the same sequence site, designated as the monoclonal integration. Using Southern blot hybridization (SBH) and sequenced tagged site polymerase chain reaction assays, we examined the proviral status in 558 clinical specimens from 350 patients who are suspected to have ATL. A total of 321 specimens (57.5%) from 241 patients showed positive results for the monoclonal integration according to SBH, using EcoR1 and Pst1. The 241 patients consisted of 136 patients (56.4%) with the complete provirus (C-type), 62 patients (25.7%) with a defective provirus (D-type), and 43 patients (17.8%) with multibands (M-type). The incidence of the D- and M-types were in the order of smoldering, chronic, and acute subtypes of ATL, suggesting that such an aberrant proviral status is generated on the way to multistep carcinogenesis and is subsequently clinically important for the malignant behavior of the disease. Moreover, our data showed that the partial deletion of the proviral genome is initiated first at the site of the gag region and spreads into the sites of the pol and env regions, whereas the long terminal repeats and pX regions are almost always conserved. These results suggest that analysis of the proviral status provides useful diagnostic and virologic-oncological information about ATL and HTLV-1 pathology, especially the important role of pX gene in tumorigenesis.

The role of quorum-sensing systems in a mouse model of chronic Pseudomonas aeruginosa infection was studied. A chronic P. aeruginosa respiratory infection model was established by placement of a tube pre-coated with strain PAO1 (wild-type) or a quorum-sensing mutant, namely PAO-JP1 (Delta lasI), PDO100 (Delta rhlI) or PAO-JP2 (Delta lasI/Delta rhlI), in the bronchus. At day 14 after infection, the numbers of viable bacteria in the quorum-sensing-mutant groups were lower than in the wild-type group. Histopathological examination showed milder inflammatory changes in the lungs infected with the mutant groups compared with the wild-type group. In the bronchoalveolar lavage fluid from the quorum-sensing-system-mutant groups the proportion of neutrophils was lower than in wild-type group. These findings indicate that the quorum-sensing system plays an important role in chronic P. aeruginosa respiratory infection.

The prevalence and the antimicrobial susceptibilities of bacterial pathogens in acute upper respiratory tract infections (AURTIs) is not clear. We conducted a prospective community-based multicenter study in 45 centers across Nagasaki, Japan, between December 2001 and April 2002. We examined the nasopharyngeal or throat isolates in 930 adult outpatients with AURTIs. Potential bacterial pathogens, including Streptococcus pyogenes (from 6.8% patients), S. pneumoniae (5.3%), S. milleri group (2.0%), Staphylococcus aureus (26.0%), Moraxella catarrhalis (7.4%), Haemophilus influenzae (17.6%), and Klebsiella pneumoniae (1.2%), were isolated from 51.8% of the patients. Penicillin nonsusceptible phenotype accounted for 44.9% of S. pneumoniae isolates. Among Staphylococcus aureus isolates, 9.1% were methicillin-resistant. In H. influenzae isolates, 6.7% produced beta-lactamase and 23.2% were beta-lactamase-negative ampicillin-resistant. The results indicated that the potential bacterial pathogens were detected in the remarkable population of the adults with AURTIs and the current antimicrobial susceptibilities of such pathogens.

A series of gastroenteritis outbreaks caused by noroviruses (NVs) among tourist groups from several prefectures was associated with eating a lunch prepared by a restaurant in Nagasaki City, Japan, on 18 and 19 November 2003. A retrospective cohort study was performed to estimate the magnitude of the outbreak and identify the source of infection. Epidemiological information was obtained through the local public health centers in the areas where the illness occurred. Stool and vomit specimens and food and environmental samples were analyzed by reverse transcription-PCR with genogroup-specific primers. Positive samples were sequenced and analyzed phylogenetically. Of 1,492 tourists who ate a lunch prepared by the restaurant during the 2-day period, 660 (44.2%) developed illness, with an average incubation time of 31.2 h. Whereas NVs were not detected in any food samples, identical sequences most closely related to the Mexico genotype of genogroup II NV were found in specimens from case patients, restaurant staff, and the kitchen table. Food handlers were concluded to be the source of the outbreak as a result of the contamination of several meals. The series of outbreaks described here exemplifies the role of tourism as a contemporary way to distribute a single infectious agent to multiple and geographically remote areas.

Adult T-cell leukemia (ATL), which is a mature T-cell malignancy that develops from human T-cell leukemia virus type-1 (HTLV-1)-infected T-cells, is diagnosed based on morphologic, immunophenotypic, serologic, and genetic characteristics. In particular, Southern blot hybridization (SBH) and polymerase chain reaction analyses for antigen receptor genes and the retrovirus of HTLV-1 provide a diagnostic hallmark for the clonality of leukemic cells and the causative agent of the disease. We report here a case of an ATL cell line, designated as SO4 cells, established from primary ATL cells presenting with an irrational genetic abnormality of the immunoglobulin heavy chain (IgH)-rearranged band in spite of harboring a clonally rearranged T-cell receptor gene and a clonally integrated provirus of HTLV-1 within their genomic DNA. Moreover, fluorescence in situ hybridization analysis using the IgH (14q32) dual-color break-apart probe revealed 3 pair-signals of colocalizing red and green spots, implying 2 intact and 1 amplified 14q32 regions without translocation, where the region contains the IgH gene locus. Although the exact mechanism remains to be elucidated, some alteration of a portion of the amplified 14q32 region seems to have a role in the false-positive band pattern in the SBH. The SO4 cells, in the hematology laboratory, will provide a lesson about the pitfalls of genetic tests for mature T-cell neoplasms and contribute to the genetic elucidation of leukomogenesis as an in vitro model.

Clinical studies of sixteen cases with pulmonary cryptococcosis, during the past six years between 1998 and 2004, were peformed mainly with respect to serum cryptococcal antigen titer. Serum cryptococcal antigen was positive in twelve of 16 cases, the other three cases were diagnosed by VATS, the other one by positive culture of cryptococcus in BALF. In these twelve cases, the serum cryptococcal antigen titer was continuously tested after treatment. The serum cryptococcal antigen titer decreased from half to 6 months after treatment. And the cryptococcal Ag changed to negative in six of the 12 cases by antifungal agents from 5 to 19 months. But four cases whose pneumonia was severe tended to have a high titer level of cryptococcal antigen and were positive for a long period. In the Chest CT of four pulmonary cryptococcosis case with negative cryptococcal antigen, all of the maximum nodule size was less than or equal to 15mm in diameter.

Measurement of blood (1-->3)-beta-D-glucan is useful for early diagnosis and follow-up of the therapeutic process of deep seated mycoses. The Fungitec G test MK (Seikagaku Corp., Tokyo) kit using alkaline-pretreatment followed by chromogenic kinetic assay has been widely used in Japan because of its high sensitivity and easy handling of a large number of samples. Discrepancy in the levels of (1-->3)-beta-D-glucan and/or in the quantitative judgement, however, has been pointed out between this kit and other commercial kits. One of the reasons for this discrepancy has been reported to be non-specific reactions caused by substances other than beta-glucan. In this study, we have improved the alkaline pretreatment reagent by changing the concentration of KOH and salts, resulting in a marked reduction of the non-specific reaction. Recovery of standard beta-glucan added to plasma or serum after the improved pretreatment was 80 to 120%, and no amidolytic activity was detected either in plasma or in serum. By the improved pretreatment, the incidence of non-specific reactions, i.e., those that exceed the quantitation limit (3.9 pg/mL), were markedly decreased from 139 to 16 out of 200 plasma samples and from 106 to 22 out of 170 serum samples. The incidence of strong non-specific reactions, i.e., those that exceed the cut-off level (20 pg/mL), were also decreased from seven to one with plasma and seven to zero with serum samples. Correlation between corrected beta-glucan measurements by the current pretreatment and non-corrected ones by the improved pretreatment was quite good. The improved method is thus expected to decrease the frequency of non-specific false-positive reactions, with the high sensitivity of Fungitec G test MK.

Tuberculosis was diagnosed in a person who had stayed in a shelter after the 2011 Great East Japan Earthquake. A contact investigation showed that the prevalence of latent tuberculosis infection among other evacuees at the shelter was 20%. Our report underscores the importance of tuberculosis prevention and control after natural disasters.

The features of chronic airway diseases, including chronic bronchitis, cystic fibrosis, bronchiectasis, and diffuse panbronchiolitis, include chronic bacterial infection and airway obstruction by mucus.Pseudomonas aeruginosais one of the most common pathogens in chronic lung infection, and quorum-sensing systems contribute to the pathogenesis of this disease. The quorum-sensing signal molecule [N-(3-oxododecanoyl) homoserine lactone (3O-C12-HSL)] not only regulates bacterial virulence but also is associated with the immune response. In this study, we investigated whether 3O-C12-HSL could stimulate the production of a major mucin core protein, MUC5AC. The effect of a macrolide on MUC5AC production was also studied. 3O-C12-HSL induced NCI-H292 cells to express MUC5AC at both the mRNA and the protein levels in time- and dose-dependent manners. A 15-membered macrolide, azithromycin, inhibited MUC5AC production that was activated by 3O-C12-HSL. 3O-C12-HSL induced extracellular signal-regulated kinase (ERK) 1/2 and I-κB phosphorylation in cells, and this induction was suppressed by azithromycin. 3O-C12-HSL-induced MUC5AC production was blocked by the ERK pathway inhibitor PD98059. Our findings suggest that theP. aeruginosaautoinducer 3O-C12-HSL contributes to excessive mucin production in chronic bacterial infection. Azithromycin seems to reduce this mucin production by interfering with intracellular signal transduction.

The objective of this study was to investigate the antimicrobial activities of saturated fatty acids and fatty amines against methicillin-resistant Staphylococcus aureus (MRSA). The antimicrobial activity of saturated fatty acids and fatty amines was determined by oxygen meters with multi-channels and disposable oxygen electrode sensors (DOX-96). Lauric acid, the most effective among the saturated fatty acids, showed antimicrobial activity at 400 μg/ml against methicillin-susceptible Staphylococcus aureus (MSSA) and MRSA. The minimal inhibitory concentration (MIC) of fatty amines depended on each hydrophobic chain length. The MIC of myristylamine was 1.56 μg/ml; most effective of the fatty amines. In time-kill curves, lauric acid and myristylamine produced a bactericidal effect and a bacteriostatic effect at 4-fold the MIC, respectively. The antimicrobial activities of lauric acid and myristylamine were decreased by human plasma. Cytotoxicity of 3 saturated fatty acids and 3 fatty amines was examined in cultured endothelial cells. Although cytotoxicity of fatty amines was severer than that of saturated fatty acids, myristylamine showed the highest value of apparent therapeutic index among them. DOX-96 was useful for screening antimicrobial substances, especially in the case of insoluble substances. We found that myristylamine showed anti-MRSA activity comparable to that of vancomycin and teicoplanin., Biological & Pharmaceutical Bulletin v.27(9) p.1321-1326, 2004

Background: Quinupristin-dalfopristin (Q-D) is a mixture of quinupristin and dalfopristin, which are semisynthetic antibiotics of streptogramin groups B and A, respectively. Methods: We compared the effect of Q-D to that of vancomycin (VCM) in murine models of hematogenous pulmonary infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and VCM-insensitive S. aureus (VISA). Results: Treatment with Q-D resulted in a significant decrease in the number of viable bacteria in the lungs of mice in an MRSA infection model [Q-D 100 mg/kg, Q-D 10 mg/kg, VCM and control (mean ± SEM): 2.99 ± 0.44, 6.38 ± 0.32, 5.75 ± 0.43 and 8.40 ± 0.14 log10 CFU/lung, respectively]. Compared with VCM, high-dose Q-D significantly reduced the number of bacteria detected in the VISA hematogenous infection model [Q-D 100 mg/kg, Q-D 10 mg/kg, VCM and control (mean ± SEM): 5.17 ± 0.52, 7.03 ± 0.11, 7.10 ± 0.49 and 7.18 ± 0.36 log10 CFU/lung, respectively]. Histopathological examination confirmed the effect of Q-D. Conclusion: Our results suggest that Q-D is potent and effective in the treatment of MRSA and VISA hematogenous pulmonary infections.

We compared the effects of DQ-113, a new quinolone, to those of vancomycin (VCM) and teicoplanin (TEIC) in murine models of hematogenous pulmonary infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and VCM-insensitive S. aureus (VISA). The MICs of DQ-113, VCM, and TEIC for MRSA were 0.125, 1.0, and 0.5μ g/ml, respectively; and those for VISA were 0.25, 8.0, and 8.0μ g/ml, respectively. Treatment with DQ-113 resulted in a significant decrease in the number of viable bacteria in the lungs of the mice used in the MRSA infection model (counts in mice treated with DQ-113, VCM, and TEIC and control mice, 6.33 ± 0.22, 7.99± 0.14, 7.36 ± 0.20, and 8.47 ± 0.22 log 10 CFU/lung [mean ± standard error of the mean], respectively [ P < 0.01 for the group treated with DQ-113 compared with the group treated with VCM or TEIC or the untreated group]). Mice infected with VISA were pretreated with cyclophosphamide, and the survival rate was recorded daily for 10 days. At the end of this period, 90% of the DQ-113-treated mice were still alive, whereas only 45 to 55% of the mice in the other three groups were still alive ( P < 0.05 for the group treated with DQ-113 compared with the group treated with VCM or TEIC or the untreated group]). DQ-113 also significantly ( P < 0.05) reduced the number of viable bacteria in the lungs compared with those in the lungs of the other three groups (counts in mice treated with DQ-113, VCM, and TEIC and control mice, 5.76 ± 0.39, 7.33 ± 0.07, 6.90± 0.21, and 7.44 ± 0.17 log 10 CFU/lung, respectively). Histopathological examination revealed milder inflammatory changes in DQ-113-treated mice than in the mice in the other groups. Of the antibiotics analyzed, the parameters of area under the concentration-time from 0 to 6 h (AUC 0-6 )/MIC and the time that the AUC 0-6 exceeded the MIC were the highest for DQ-113. Our results suggest that DQ-113 is potent and effective for the treatment of hematogenous pulmonary infections caused by MRSA and VISA strains.

Long-term treatment of macrolide antibiotics is considered an effective treatment for diffuse panbronchiolitis (DPB). Although hypersecretion is a common feature of this disease, and it is known that macrolides inhibit mucin production, the mechanism of the effect on mucin production is unclear. The aim of our study was to determine the production of muc5ac core protein, a major core protein of mucin in airway secretion, and the effect of clarithromycin treatment on such production in a mouse model mimicking DPB. Alcian blue-periodic acid-Schiff-positive cells were detected in the lungs of Pseudomonas aeruginosa-infected mice. Western blots of these mice showed muc5ac glycoprotein at day 1 and increased progressively from day 4 to day 14 after inoculation of bacteria. Clarithromycin (10 mg · kg-1· day-1for 7 days) significantly reduced the muc5ac expression at both the mRNA and protein levels. To investigate the role of molecules upstream in muc5ac regulation, we examined the role of mitogen-activated protein kinase. Extracellular signal-regulated kinase 1/2 phosphorylation increased in the infected lung and decreased after treatment. Our results suggest that overproduction of muc5ac plays an important role in the pathogenesis of DPB and that clinical improvement following macrolide therapy seems to involve, at least in part, its inhibition of mucin overproduction, through modulation of intracellular signal transduction.

The aim of this study was to determine whether whole-blood interferon-gamma (IFN-gamma) production correlates with the radiographic extent of pulmonary tuberculosis before treatment. The subjects were 40 human immunodeficiency virus-negative patients with pulmonary tuberculosis and 36 healthy volunteers. The concentrations of IFN-gamma in whole blood stimulated with Mycobactrium tuberculosis purified protein derivatives (tuberculous PPD) and phytohemagglutinin (PHA) were evaluated. PHA-stimulated IFN-gamma (PHA-IFN-gamma) was lower in the patients than in healthy volunteers (p0.05), and inversely correlated with the disease extent (p0.01). Tuberculous PPD-stimulated IFN-gamma as a percentage of PHA response (tuberculous PPD-IFN-gamma/PHA-IFN-gamma) was higher in the patients than in healthy volunteers (p0.05). However, tuberculous PPD-IFN-gamma/PHA-IFN-gamma did not correlate with the disease extent. Our results indicate that the tuberculous PPD-IFN-gamma/PHA-IFN-gamma may be useful for the diagnosis of tuberculosis but not for evaluating the disease severity, and suggest that PHA-IFN-gamma could be considered as a marker of disease severity.

We developed a real-time (RT) PCR quantitative assay to measure the level of the integrated viral genome of HTLV-1 in host peripheral blood-mononuclear cells (PB-MNC) from healthy carriers and patients with adult T-cell leukemia (ATL). All of the clinical specimens were serologically and molecularly characterized by enzyme-linked immunosorbent assay (ELISA) and Southern blot hybridization (SBH) analyses. The assay system for quantifying the proviral copy level was sensitive, accurate, and reproducible over a wide range of density from 100 to 0.1% with a coefficient of variation (%) of 4.5 to 9.6. The proviral load of the healthy carriers and patients with ATL was 301 +/- 339 copies per 10(4) MNC (3 +/- 3.4%) on average and varied depending on the ATL cell number and the SBH band-status of single or multiple bands. In ATL cases with multiple bands detected by SBH analysis, their ATL cells were shown to harbor multiple copies within one ATL cell, so that the corrected copy number interpolated by the band number in SBH was closely equivalent to the expected ATL cell number in PB, corresponding to the virus-infected cell burden. The proviral load in healthy carriers ranged from 0.1 to 15% of PB-MNC, and, in combination with the fraction (%) of ATL-like flower cells defined by PB smear morphology, enabled carriers to be subgrouped into three categories. This result indicates that the detection of proviral load by(RT) PCR is sufficient and relevant to monitor the infected cell number in the PB and to evaluate the HTLV-1 pathologic status.

Background: The genetic identities of mucins secreted in the airways of patients with diffuse panbronchiolitis (DPB) have not been previously investigated, although hypersecretion is a common feature of this disease. Objective: The purpose of this study was to determine the production of MUC5AC, a major core protein of mucin in airway secretion, and the effect of macrolide treatment on such production in patients with DPB. Method: We performed Western blot analysis for MUC5AC of bronchoalveolar lavage fluid patients. Cases consisted of four groups including patients with DPB, idiopathic pulmonary fibrosis (IPF), and sarcoidosis, and healthy volunteers. Results:MUC5AC was detected in DPB patients but not in other groups. Macrolide treatment tended to inhibit such production in DPB patients. Conclusions: Our results suggest that overproduction of MUC5AC plays an important role in the pathogenesis of DPB.

We have reported two orthopedic patients with Methicillin-resistant Staphylococcus aureus (MRSA) infections successfully treated with linezolid. The first case was a 64-years-old man with bacteremia, spondylitis and psoas abscesses caused by MRSA. He was treated with arbekacin (ABK) and vancomycin (VCM), and then became afebrile. However he complained of a recurrence of fever and oliguria, we administered linezolid for two weeks intravenously because of fluctuating renal dysfunction. Thereafter his clinical conditions improved. The second case was a 26-years-old man with MRSA infection of the pelvis after a trauma. He was treated with teicoplanin (TEIC) for two weeks. However the minimum inhibiratory concentrations (MICs) of TEIC and VCM against MRSA, isolated from the wounds, were 4 micrograms/ml each, we administered linezolid intravenously and the patient was successfully treated in four weeks. Linezolid has been proven to have high efficacy against MRSA by some trials abroad. But the agent has the indication only for VRE by the Medical Insurance in Japan. These cases also suggest that linezolid is useful for MRSA infections in these cases.

The objective of this study was to investigate the applicability of new oxygen meters with multi-channels and disposable oxygen electrode sensors (DOX-96) on the antimicrobial susceptibility testing of clinical bacterial isolates. The oxygen amount in the wells of 96-well plates was converted into current through electrodes. Bacterial inoculation decreased the oxygen amount in the wells because viable bacteria consume the oxygen. On the other hand, a failure of bacteria to consume oxygen was observed in the presence of potent antimicrobial agents, representing a serious arrest of bacterial metabolism usually leading to stasis or death. Based on these results, the minimum inhibitory concentration was determined by DOX-96 (MICdox). The MICdox showed good agreement with MIC measured by the standard broth microdilution method (98.2%). DOX-96 was also useful for turbid samples such as Mueller-Hinton broth containing 0.1% lipid emulsion. The MICdox in turbid samples showed good agreement with those in clear samples (100.0%). These results indicate that the newly developed DOX-96 is very useful in antimicrobial susceptibility testing even in turbid clinical samples such as colloidal products and turbid biological, Biological & Pharmaceutical Bulletin v.26(9) p.1229-1234, 2003