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Objective We evaluated biofilm production ability (BPA) of Streptococcus agalactiae isolates from companion animals/humans and clarified the relationship between BPA populations and other microbiological features. Methods Companion animal-/human-origin isolates were collected with host information. We measured BPA using crystal violet staining, via virulence-associated gene profiling (hylB-pavA-pilB-spb1-srtC1-brpA), capsular genotyping, multilocus sequence typing, and antimicrobial resistance (AMR) phenotyping/genotyping. Significant difference in BPA of isolates from different hosts was assessed. We analyzed the association between BPA populations and the virulence genotypes, capsular genotypes, sequence types/clonal complexes, and AMR phenotypes/genotypes. Inhibitory effect of berberine on BPA was evaluated. Results Five, twenty-six, and twenty-six isolates belonged to strong, moderate, and weak biofilm producers, whereas seventeen showed no biofilm production. We defined strong, moderate, or weak biofilm producers as the producer group (n = 57) to conduct a comparative analysis between the producer and non-producer populations. There was a significant correlation between the producer population and vaginal specimen. We found significant associations between the producer group and presence (57.9%) of pilB and between the non-producer population and presence (70.6%) of spb1. There was no association between the producer group and capsular genotypes, sequence types/clonal complexes, and AMR phenotypes/genotypes (except for a significant correlation between the producer group and AMR to minocycline). We confirmed inhibitory effect of berberine at sub-minimum inhibitory concentrations (MICs) against the type strain on BPA. Conclusion Our observations suggest that S. agalactiae harboring pilB is more capable of producing biofilms, with berberine inhibitory effect at sub-MICs on BPA.

Streptococcus canis (Sc)-origin M-like protein (SCM) binds to plasminogen and immunoglobulin G and facilitates anti-phagocytic properties. We aimed to determine the prevalence and diversity of the scm gene in Sc isolates from diseased companion animals in Japan and to propose potential SCM alleles of amino acid (AA) sequences. We collected β-hemolytic streptococci from diseased animals with host information nationwide in 2015 and 2017. After Sc identification and scm gene amplification and sequencing, the gene’s prevalence and relationship between its presence and host information were determined. Furthermore, phylogenetic trees of AA sequences were constructed, and classification and distribution of SCM alleles based on variations of AA sequences were conducted. The scm detection rates were 70.6% (n = 48, 2015) and 82.9% (n = 97, 2017). There was a relationship between scm presence and Tokyo in 2015 and 2017. We found an association between scm detection and dogs in 2017 alone. Major sequence sizes were 1311 bp, 1308 bp, and 1305 bp. Using the phylogenetic trees of AA sequences, we confirmed shared positions of five identical sequence patterns in both periods. Nine SCM alleles were determined with six signal-peptide types. Most prevalent alleles were type 1, type 2, and type 4 in both periods. Our observations suggest prevalence and diversity of scm in animal-origin Sc isolates in Japan.

Infections caused by multidrug-resistant (MDR) Pseudomonas aeruginosa are very difficult to treat. The aim of this study was to develop more effective treatments by investigating in vitro the effects of combinations of antibiotics against 47 MDR P. aeruginosa isolates harbouring various resistance factors. The isolates included 41 (87%) metallo-β-lactamase (MBL)-positive strains, 37 (79%) strains with mutations in OprD and 46 (98%) strains carrying the genes encoding aminoglycoside-modifying enzymes (AMEs). The quinolone resistance-determining region was mutated in all of the strains. These strains were classified into 16 groups according to amplified fragment length polymorphism and resistance factors. The effects of combinations of antibiotics on 16 representative strains were determined using a ‘Break-point Checkerboard Plate’ assay. Combinations of amikacin + aztreonam (coverage rate, 81.3%) and arbekacin + aztreonam (93.8%) inhibited growth. In contrast, combinations of ciprofloxacin + meropenem (6.3%) and ciprofloxacin + ceftazidime (12.5%) were much less effective. Aztreonam and arbekacin (or amikacin) are not substrates for MBLs and AMEs, respectively. We conclude that the combined effects of these drugs were possibly because of resistance factors.

A catastrophic earthquake occurred off the Pacific coast of Japan on 11 March 2011, striking the northeastern part of the country. The earthquake was followed by huge tsunamis, which destroyed many coastal cities and towns. Many displaced people moved into shelters or temporary homes supplied by the government, not only because of disruptions to community utility services but also because of health risks associated with nuclear power plant malfunctions in Fukushima. In this review, we summarize the characteristics of illnesses that occurred in the aftermath of this earthquake, including respiratory tract infection (tsunami-related aspiration pneumonia, legionellosis and influenza), wound infection (tetanus) and other infections (food poisoning, tsutsugamushi disease and measles). Our review also outlines several activities concerning the management of illnesses and infection control.

We report the isolation of Helicobacter cinaedi (previously called " Campylobacter-like organism") from the blood of an immunosuppressed Japanese patient receiving immunosuppressive therapy after renal transplantation. The identification of H. cinaedi was based on the findings of microscopic examinations, biochemical properties, and 16S rRNA gene nucleotide sequences. H. cinaedi bacteremia should be considered as one of the critical infectious diseases in immunocompromised patients, and the sequencing of 16S rRNA may be a useful method to confirm the identification of this organism.

Periodontal tissue shows various morphological changes with ageing. A typical example of these changes is the apical migration of the junctional epithelium. The distribution of fibronectin and laminin was investigated by immunofluorescent and immunoelectron-microscope methods in mice to clarify any possible functional roles of these proteins in the apical migration of junctional epithelium. Apical migration begins in 20-week-old mice, and then progresses with increasing age until the mice reach 80 weeks. In the apical tip of the junctional epithelium, fibronectin was demonstrated in the sub-epithelial fibrillar matrix, preceding the progression of apical migration. Fibronectin was also demonstrated in association with the stromal side of focal contacts between epithelial cells and basement membrane. Therefore, these focal contacts are assumed to be fibronectin receptors. There was no apparent relation between the localization of laminin and the migration of the junctional epithelium. These results suggest that the fibronectin provides a provisional matrix for the apical migration of junctional epithelium, but laminin does not appear to play a major part in that migration.

Human parvovirus B19 (B19) has been described as a causative agent of chronic anemia in human immunodeficiency virus type-1 (HIV-1)-infected patients. We report an HIV-1 infected patient who had been receiving anti-retroviral therapy who showed sudden pancytopenia. Primary B19 infection was confirmed by the detection of plasma viremia and seroconversion. Although clearance required a prolonged period of time, the patient eventually cleared the B19 viral DNA from the plasma. More than likely, highly active anti-retroviral therapy (HAART), including a protease inhibitor, played a role in clearing the virus.

The cause and origin of Kaposi's sarcoma (KS) remain an enigma. Recently, Chang et al. reported a DNA fragment resembling human gamma herpesvirus that was specifically associated with KS tissue. In this paper, we report examination of three Japanese patients for presence of the KS-associated herpesvirus-like (KSHV) sequences. KSHV sequences were present in two of these patients, but could not be confirmed in the third because of DNA degradation. The KSHV sequences appeared to be present mainly in those tissues with KS invasion. Our results further demonstrate the presence of KSHV in KS lesions and support its role in the pathogenesis of KS.