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The emergence of unusual G9P[8]-E2 human rotaviruses in the Tokyo metropolitan area, Japan, in 2018 has been reported. During rotavirus strain surveillance in different regions of Japan (Mie, Okayama, and Chiba prefectures), G9P[8]-E2 strains were detected in children with diarrhea from all three prefectures. Here, we characterized the whole genome of seven representative G9P[8]-E2 strains. In the full-genome-based analysis, the seven study strains exhibited a unique genotype configuration with the NSP4 gene of genogroup 2 in a genogroup 1 genomic backbone: G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E2-H1. This genotype constellation was shared by the Tokyo G9P[8]-E2 strains. Phylogenetic analysis showed that all 11 genes, except NSP4, of the seven study strains appeared to have originated from co-circulating Wa-like G9P[8]-E1 strains. In contrast, NSP4 appeared to have originated from the co-circulating DS-1-like G2P[4]-E2 strains. Thus, G9P[8]-E2 strains appear to be derived through reassortment between G9P[8]-E1 and G2P[4]-E2 strains in Japan. Notably, the seven study G9P[8]-E2 strains and Tokyo G9P[8]-E2 strains were revealed to have 11-segment genomes almost indistinguishable from one another in their sequences (99.3-100%), indicating all these G9P[8]-E2 strains had a common origin. To our knowledge, this is the first description of the rapid spread of G9P[8]-E2 strains across a country.

A study was conducted of the 1,225 Pseudomonas aeruginosa strains that were isolated at 20 medical institutions in the Kinki district between 2011 and 2013 to determine their antimicrobial susceptibility and to characterize the strains of multidrug-resistant Pseudomonas aeruginosa (MDRP) and the metallo-β-lactamase (MBL) -producing strains. The MIC50/MIC90 values (μg/mL) of the various antimicrobial agents were as follows: imipenem, 2/>8; meropenem, 1/>8; doripenem, 0.5/8; biapenem, 1/>8; tazobactam/piperacillin, 8/>64; piperacillin, 8/>64; sulbactam/cefoperazone, 8/64; cefepime, 4/16; cefozopran, 2/>16; aztreonam, 8/>16; amikacin, 4/16; levofloxacin, 1/>4; and ciprofloxacin, 0.25/>2. From the viewpoint of the annual changes in the susceptibility rates (according to the CLSI guidelines [M100-S22]), the susceptibility to tazobactam/piperacillin, piperacillin, cefepime, cefozopran and aztreonam decreased in 2013. On the other hand, two antimicrobial agents showed high susceptibility rates each year; amikacin (94.0-95.6%) showed the highest rate, followed by doripenem (80.3-82.6%). With the exception of amikacin, there were substantial inter-institutional differences in antimicrobial susceptibility. In comparison to the previous CLSI guidelines (M100-S21), the new CLSI guidelines (M100-S22) on the use of carbapenems and penicillins show that the MIC80 has been affected. The MDRP detection rates in 2011, 2012 and 2013 were 1.8% (8 strains), 1.8% (8 strains), and 2.8% (10 strains), respectively. The MBL detection rates were as follows: bla(VIM-2), 0.2% (1 strain) in 2011; bla(IMP-1), 0.9% (4 strains) in 2012, and 1.7% (6 strains, including bla(IMP-1) [3 strains], bla(IMP-2) [2 strains] and bla(VIM-2) [1 strain]) in 2013.

Oncolytic virus therapy is a promising new therapeutic method, one of an eagerly anticipated class of biological therapies against cancer. There are many different classes of oncolytic virus. One of these, herpes oncolytic virus, is strongly oncolytic and has a large DNA genome as 150k bp. HF10 is a spontaneous mutant of herpes simplex virus -1 (HSV-1) that replicates within tumors and destroys cancers without damaging normal tissue and organs. Clinical trials of HF10 are underway in Japan and the United States. The first pilot study of HF10 was initiated in Japan in 2003. This study examined the safety and efficacy of HF10 in the treatment of breast cancer and head and neck cancers; the trial also included careful dose escalation studies. In 2005, a clinical trial using HF10 to treat pancreatic cancer was initiated. screened In this Japanese study, 17 patients received HF10 in their tumor sites. A clinical trial in the United States is also ongoing to evaluate safety, tolerability and evidence of antitumor activity in patients with refractory superficial solid tumors. Here, we report the evaluation of the 17 patients treated in Japan. Among the patients, 6 had recurrent breast cancer, 3 had recurrent head and neck cancer, and 8 had non-resectable pancreatic cancer. No severe adverse side effects have been observed, and some therapeutic potential has been reported based on pathological findings, tumor markers, and diagnostic radiography. Those results should encourage further clinical trials of HF10 around the world.

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.

Background/aims: Advanced gastric cancer is difficult to treat due to the frequency of liver metastases and peritoneal dissemination. A combination of two new strategies, including the anti-angiogenesis inhibitor bevacizumab and an oncolytic herpes virus is a promising treatment for advanced cancer., Methodology: The effects of bevacizumab on oncolytic herpes virus replication and viral cytotoxicity were examined at varying bevacizumab concentrations and viral titers. In addition, the ability of these two new promising anticancer agents to inhibit tumor growth was studied. Histological examinations of CD31 and LacZ were used to assess angiogenesis and virus distribution within the tumor, respectively., Results: Bevacizumab did not affect viral replication or viral cytotoxicity in vitro. The combination of bevacizumab and the oncolytic herpes virus hrR3 significantly reduced tumor growth in vivo in an experimental gastric cancer model. Bevacizumab inhibited angiogenesis caused by local injection of hrR3 and induced virus spread. Bevacizumab increased the distribution of the intratumorally injected oncolytic herpes virus within the tumor., Conclusions: Combination therapy consisting of bevacizumab and an oncolytic herpes virus is a promising new treatment strategy for gastric cancer.

The antimicrobial activity of 18 antimicrobial agents were measured for the 500 Pseudomonas aeruginosa strains that had been isolated from various clinical specimens in 17 medical institutions in the Kinki district from April to July of 2008. The antimicrobial activity was excellent in the order of tobramycin (TOB), arbekacin (ABK), doripenem (DRPM), gentamicin (GM) and amikacin (AMK). Susceptible rate that was interpreted by Clinical and Laboratory Standards Institute (CLSI) was high in the order of AMK, TOB, tazobactam/piperacillin (TAZ/PIPC), DRPM, ABK. Also, the difference in susceptible rate was observed between departments, materials and institutions. Multidrug resistant strains were only 12 (2.4%) but strains that had resistance to 2 agents were 48 (9.6%), therefore, implementation of further surveillance should be continued.

Unlabelled: BACK GROUND/AIMS: Oncolytic virus therapy is becoming a promising anti-cancer therapy and oncolytic viruses have been shown to elicit anti-cancer immunity. We evaluated the anti-tumor immune responses elicited by the herpes oncolytic virus R3616 compared to a representative chemotherapy drug, 5-FU., Methodology: R3616 or 5-FU was directly injected into subcutaneous tumors of non-immunized mice. Additionally, complete adjuvant, R3616-infected MC26 cells or 5-FU plus MC26 cells were frozen, thawed and used to immunize mice. After 21 days of immunization, the adaptive immune response suppressed implanted tumor growth and prolonged survival rate. We monitored differences in the number of infiltrating CD8- and CD4-positive lymphocytes in implanted tumors by immunofluorescence., Results: R3616 induced a statistically greater number of infiltrating T cells (Thy1.2), macrophages (CD68) and dendritic cells (CD83) in injected tumors than 5-FU. The group immunized with R3616-infected MC26 cells had greater tumor suppression and longer survival rate than non-immunized mice and mice treated with 5-FU plus MC26 cells with statistically significant differences between these groups. The mice immunized with R3616-infected MC26 cells had a statistically greater number of infiltrating T cells in the implanted tumor than non-immunized and mice treated with 5-FU plus MC26 cells., Conclusions: These results indicate that oncolytic herpes virus R3616 can elicit more effective host anti-tumor immune responses than 5-FU against murine colon cancer model.

Extended-spectrum beta-lactamases, plasmid-mediated AmpC beta-lactamases (PABLs), and plasmid-mediated metallo-beta-lactamases confer resistance to many beta-lactams. In Japan, although several reports exist on the prevalence of extended-spectrum beta-lactamases and metallo-beta-lactamases, the prevalence and characteristics of PABLs remain unknown. To investigate the production of PABLs, a total of 22,869 strains of 4 enterobacterial species, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis, were collected during six 6-month periods from 17 clinical laboratories in the Kinki region of Japan. PABLs were detected in 29 (0.13%) of 22,869 isolates by the 3-dimensional test, PCR analysis, and DNA sequencing analysis. PABL-positive isolates were detected among isolates from 13 laboratories. Seventeen of 13,995 (0.12%) E. coli isolates, 8 of 5,970 (0.13%) K. pneumoniae isolates, 3 of 1,722 (0.17%) K. oxytoca isolates, and 1 of 1,182 (0.08%) P. mirabilis isolates were positive for PABLs. Of these 29 PABL-positive strains, 20 (69.0%), 6 (20.7%), 2 (6.9%), and 1 (3.4%) carried the genes for CMY-2, DHA-1, CMY-8, and MOX-1 PABLs, respectively. Pattern analysis of randomly amplified polymorphic DNA and pulsed-field gel electrophoretic analysis revealed that the prevalence of CMY-2-producing E. coli strains was not due to epidemic strains and that 3 DHA-1-producing K. pneumoniae strains were identical, suggesting their clonal relatedness. In conclusion, the DHA-1 PABLs were predominantly present in K. pneumoniae strains, but CMY-2 PABLs were predominantly present in E. coli strains. The present findings will provide significant information to assist in preventing the emergence and further spread of PABL-producing bacteria.

We calculated achievement rates of target attainment of AUC/MIC using Monte Carlo simulation (MCS). Two doses of pazufloxacin mesilate (PZFX) between q.d. and b.i.d. were compared for each species of bacterium. Concentrations for AUC of PZFX of 8 patients were measured at this hospital, and those from a phase I clinical study (phase I, 6 healthy volunteers) were used. MICs of PZFX were determined for each species of bacterium of respiratory organ origin (Pseudomonas aeruginosa, Haemophilus influenzae, Streptococcus pneumoniae, and Klebsiella pneumoniae). AUC per day of 500 mg b.i.d. used twice AUC (PZFX 500 mg x 2/day by patient, PZFX 500 mg x 2/day by phase I). Target attainment of AUC/MIC was AUC/MIC > or = 30 in S. pneumoniae and AUC/MIC > or = 125 in the other species of bacteria (P. aeruginosa, H. influenzae, and K. pneumoniae). As a result, patients showed an about 3 times higher AUC than the phase I subjects (67.9/21.9 microg/mL). In addition, the target attainment of AUC/MIC showed the highest rate in PZFX 500 mg x 2/day in patients with each type of bacteria: H. influenzae (98%), K. pneumoniae (89%), S. pneumoniae (66%), and P aeruginosa (41%). Target attainment of AUC/MIC was H. influenzae (91%), K. pneumoniae (81%), P. aeruginosa (5%), and S. pneumoniae (0%) in phase I. Therefore, the effectiveness of PZFX was estimated to be low using the MCS method with the phase I data.

Two hundred and seven clinical isolates of Pseudomonas aeruginosa were collected at Tenri Hospital between April 2003 and March 2004. We determined the minimum inhibitory concentration (MIC) of 16 antimicrobial agents, including prulifloxacin, pazufloxacin and biapenem which were recently published in Japan, against these isolates according to the guidelines of the Clinical and Laboratory Standards Institute. For the fluoroquinolones, the rank order of activity was prulifloxacin (MIC50, 0.5 microg/ml)>ciprofloxacin (1 microg/ml)> pazufloxacin (2 microg/ml)=levofloxacin (2 microg/ml)>gatifloxacin (4 microg/ml). For the carbapenems, the rank order of activity was meropenem (MIC50, 1 microg/ml)=biapenem (1 microg/ml)>imipenem (2 microg/m)>panipenem (8 microg/ml). For the cephalosporins and monobactam, the overall rank order of activity was cefozopran (MIC50, 4 microg/ml)= ceftazidime (4 microg/ml)>cefepime (8 microg/ml)=piperacillin/tazobactam (8 microg/ml)>aztreonam (16 microg/ml)= cefoperazone/sulbactam (16 microg/ml)=cefpirome (16 microg/ml). The rates of susceptibility to antimicrobial agents as per the criteria of the Japanese Society of Antimicrobial Chemotherapy were especially high for cefozopran (63%), biapenem and meropenem (61%), and pazufloxacin (53%) and ciprofloxacin (53%). These findings suggest that prulifloxacin, pazufloxacin and biapenem, which are newly introduced, are clinically effective in the treatment of infection caused with P. aeruginosa.

At Tenri Hospital in Nara prefecture of Japan, the blood culture system is managed by a medical technologist with a microbiology specialty, and the other medical technologists manage the blood culture system when the primary technologist who specializes in microbiology is not working in 24 hours. For positive cultures, the Gram staining morphology of the organism is reported direct by to the clinician by telephone within 24 hours after culture bottles are submitted to the laboratory. We, the medical technologist, discuss with the clinician the focus of infection, use of antibiotics, effects of antimicrobial therapy, and clinical background of the patient. In some cases, we examine the MICs of specific bacteria isolated from patients and calculate the pharmacokinetic (PK)/pharmacodynamic (PD) parameters(e.g., time above the MIC, area under the curve/MIC and peak concentration/MIC). We then recommend to the clinician the most suitable dosage regimen. For patients with a serious infection or renal failure requiring a special dosing regimen, we perform therapeutic-drug monitoring with various antimicrobial agents. Information for rapid diagnosis of bacteremia and suitable dosing regimens for antimicrobial agents should be provided to the clinician with the following considerations: (1)findings should be reported within 24 hours of receiving a specimen, (2)the report should include a therapeutic regimen that considers the MIC of the target bacteria, and (3)the MIC interpretive criteria that correspond to the dosage regimen should be adopted.

We have examined the antifungal activities of the available antifungal agents including micafungin (MCFG), one of the echinocandin antifungal group, against 92 yeast-like fungi isolated at our hospital during a 3-month period from November 2002 to February 2003. Determination of the antifungal susceptibility was conducted in conformity with the Standards of the Japanese Society for Medical Mycology. The MIC 80% of the antifungal agents against 4 fungi species including C. albicans (55 strains), C. tropicalis (20 strains), C. glabrata (8 strains), C. krusei (5 strains) were as follows; MCFG: 0.03-0.125 microgram/ml, amphotericin-B: 0.125-0.25 microgram/ml, 5-fluorocytosine: 0.125-16 micrograms/ml, itraconazole: 0.25-2 micrograms/ml, fluconazole: 0.5-32 micrograms/ml. The isolation rate of the drug-resistant fungi was 20% for the fluconazole (FLCZ)-resistant C. tropicalis and 33% when including the susceptible dose dependent (S-DD) class. The rate was 5% for FLCZ-resistant strains of C. albicans and 11% when including the S-DD class. However, MCFG was shown to have an excellent antifungal activity against those azole-resistant strains of Candida species. An analysis of the randomly amplified polymorphic DNA pattern (RAPD) was carried out to assess the fingerprinting of the azole-resistant strains. The results demonstrated a common pattern in 3 of the 6 strains of C. tropicalis that showed MIC of > or = 16 micrograms/ml for fluconazole, while all of the 6 strains of C. albicans demonstrated their respective patterns.

The effectiveness of time-dependent antibiotics such as beta-lactams is related to the time above the MIC (TAM, %). We constructed a program to calculate the TAMs of beta-lactams using the pharmacokinetic parameters of the Japanese dosing regimen of a phase I study of the Japanese Society for Antimicrobial Chemotherapy (JSAC), and compared them with the MIC breakpoints published by the National Committee for Clinical Laboratory Standards (NCCLS) and JSAC. If the effective TAM was assumed to be more than 40% of the dosing interval, the pharmacokinetic/pharmacodynamic (PK/PD) breakpoints calculated by our program were in agreement with the JSAC breakpoints for pneumonia within 1 dilution MIC. When comparing with the NCCLS breakpoints for Enterobacteriaceae or Staphylococcus, the PK/PD breakpoints dosing three times per day of ampicillin (1 g, intravenous dose; i.v.), piperacillin (2 g, i.v.), cefotaxime (1 g, i.v.) and cefmetazole (1 g, i.v.) were calculated to be less than 2-fold dilution MIC, and those of amoxicillin (0.25 g, oral dose; p.o.) and cefaclor (0.5 g, p.o.) were calculated to be less than 3- to 4-fold dilution of MIC. Our program could calculate TAMs and PK/PD breakpoints by inputting the two factors of MIC and dosing interval. If this information is routinely reported to physicians from clinical laboratories, an appropriate dosing schedule could be proposed for various infectious cases.

We assessed use of the MicroScan ESBL confirmation panel (Dade Behring, Tokyo, Japan) for the detection of eight Enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBL) species. Of 137 bacterial strains isolated from patients in 32 hospitals in the Kinki area of Japan, 91 produced ESBL and comprised 60 bacteria (of E. coli, K. oxytoca, and K. pneumoniae) targeted by the NCCLS ESBL test and 31 non-target bacteria such as chromosomal AmpC-producing bacteria (e.g., Serratia marcescens, Enterobacter spp.). Sensitivity and specificity of the MicroScan panel for the target bacteria were 92% and 93%, respectively; sensitivity and specificity for non-target bacteria were 52% and 100%, respectively. There were 20 ESBL-positive strains that were not inhibited by clavulanic acid in the MicroScan panel (3 of 32 ESBL-producing E. coli strains, 1 of 24 K. pneumoniae, 1 of 4 K. oxytoca, 8 of 13 E. cloacae, and 7 of 14 S. marcescens), and most of them were bacteria not targeted by the NCCLS test. In 19 of the 20 strains, the synergy effect of clavulanic acid was observed in the modified-double-disk synergy test using only the cefepime-disk. Because these strains had high MICs of > or = 16 microg/ml for cephamycins such as cefoxitin and cefmetazole, these strains might produce high levels of AmpC in addition to ESBL. The MicroScan ESBL confirmation panel showed excellent performance in detecting target, but not other bacteria. Addition of cefepime and clavulanic acid to the MicroScan panel may significantly improve detection of non-target bacteria.