Differential expression of pentraxin 3 in neutrophils.

Pentraxins belong to the superfamily of conserved proteins that are characterized by a cyclic multimeric structure. Pentraxin 3 (PTX3) is a long pentraxin which can be produced by different cell types upon exposure to various inflammatory signals. Inside the neutrophil PTX3 is stored in form of granules localized in the cytoplasm. Neutrophilic granules are divided into three types: azurophilic (primary) granules, specific (secondary) granules and gelatinase (tertiary) granules. PTX3 has been considered to be localized in specific (secondary) granules. Immunofluorescent analyses using confocal laser microscopic examination were performed to clarify the localization of all three groups of granules within the cytoplasm of the mature neutrophils and neutrophils stimulated with IL-8. Furthermore, PTX3 was localized in primary granules of promyelocyte cell line HL-60. As a result, we suggest that PTX3 is localized not only in specific granules, but is also partly expressed in primary and tertiary granules. After the stimulation with IL-8, irregular reticular structures called neutrophil extracellular traps (NETs) were formed, three types of granules were trapped by NETs and PTX3 showed partial colocalization with these granular components. PTX3 localized in all three types of granules in neutrophils may play important roles in host defense.

A strategy for low-cost portable monitoring of plasma drug concentrations using a sustainable boron-doped-diamond chip.

On-site monitoring of plasma drug concentrations is required for effective therapies. Recently developed handy biosensors are not yet popular owing to insufficient evaluation of accuracy on clinical samples and the necessity of complicated costly fabrication processes. Here, we approached these bottlenecks via a strategy involving engineeringly unmodified boron-doped diamond (BDD), a sustainable electrochemical material. A sensing system based on a ∼1 cm2 BDD chip, when analysing rat plasma spiked with a molecular-targeting anticancer drug, pazopanib, detected clinically relevant concentrations. The response was stable in 60 sequential measurements on the same chip. In a clinical study, data obtained with a BDD chip were consistent with liquid chromatography-mass spectrometry results. Finally, the portable system with a palm-sized sensor containing the chip analysed ∼40 µL of whole blood from dosed rats within ∼10 min. This approach with the 'reusable' sensor may improve point-of-monitoring systems and personalised medicine while reducing medical costs.

Analysis of Pharmacokinetics in the Cochlea of the Inner Ear.

Hearing loss affects >5% of the global population and therefore, has a great social and clinical impact. Sensorineural hearing loss, which can be caused by different factors, such as acoustic trauma, aging, and administration of certain classes of drugs, stems primarily from a dysfunction of the cochlea in the inner ear. Few therapeutic strategies against sensorineural hearing loss are available. To develop effective treatments for this disease, it is crucial to precisely determine the behavior of ototoxic and therapeutic agents in the microenvironment of the cochlea in live animals. Since the 1980s, a number of studies have addressed this issue by different methodologies. However, there is much less information on pharmacokinetics in the cochlea than that in other organs; the delay in ontological pharmacology is likely due to technical difficulties with accessing the cochlea, a tiny organ that is encased with a bony wall and has a fine and complicated internal structure. In this review, we not only summarize the observations and insights obtained in classic and recent studies on pharmacokinetics in the cochlea but also describe relevant analytical techniques, with their strengths, limitations, and prospects.

Community-acquired methicillin-resistant Staphylococcus aureus: community transmission, pathogenesis, and drug resistance.

Methicillin-resistant Staphylococcus aureus (MRSA) is able to persist not only in hospitals (with a high level of antimicrobial agent use) but also in the community (with a low level of antimicrobial agent use). The former is called hospital-acquired MRSA (HA-MRSA) and the latter community-acquired MRSA (CA-MRSA). It is believed MRSA clones are generated from S. aureus through insertion of the staphylococcal cassette chromosome mec (SCCmec), and outbreaks occur as they spread. Several worldwide and regional clones have been identified, and their epidemiological, clinical, and genetic characteristics have been described. CA-MRSA is likely able to survive in the community because of suitable SCCmec types (type IV or V), a clone-specific colonization/infection nature, toxin profiles (including Pantone-Valentine leucocidin, PVL), and narrow drug resistance patterns. CA-MRSA infections are generally seen in healthy children or young athletes, with unexpected cases of diseases, and also in elderly inpatients, occasionally surprising clinicians used to HA-MRSA infections. CA-MRSA spreads within families and close-contact groups or even through public transport, demonstrating transmission cores. Re-infection (including multifocal infection) frequently occurs, if the cores are not sought out and properly eradicated. Recently, attention has been given to CA-MRSA (USA300), which originated in the US, and is growing as HA-MRSA and also as a worldwide clone. CA-MRSA infection in influenza season has increasingly been noted as well. MRSA is also found in farm and companion animals, and has occasionally transferred to humans. As such, the epidemiological, clinical, and genetic behavior of CA-MRSA, a growing threat, is focused on in this study.

In vitro susceptibility to antimicrobial agents and ultrastructural characteristics related to swimming motility and drug action in Campylobacter jejuni and C. coli.

Campylobacter jejuni has recently been noted as the most common cause of bacterial food-borne diseases in Japan. In this study, we examined in vitro susceptibility to 36 antimicrobial agents of 109 strains of C. jejuni and C. coli isolated from chickens and patients with enteritis or Guillain-Barré syndrome from 1996 to 2009. Among these agents, carbapenems (imipenem, meropenem, panipenem, and biapenem) showed the greatest activity [minimal inhibitory concentration (MIC)(90), 0.03-0.125 microg/ml]. This was followed by sitafloxacin (MIC(90), 0.25 microg/ml), furazolidone and azithromycin (MIC(90), 0.5 microg/ml), gentamicin and clindamycin (MIC(90), 1 microg/ml), and clavulanic acid (beta-lactamase inhibitor; MIC(90), 2 microg/ml). All or most strains were resistant to aztreonam, sulfamethoxazole, and trimethoprim. Marked resistance was also observed for levofloxacin and tetracyclines. Resistance was not present for macrolides and rare for clindamycin. C. jejuni (and C. coli) exhibited high swimming motility and possessed a unique end-side (cup-like) structure at both ends, in contrast to Helicobacter pylori and Vibrio cholerae O1 and O139. The morphology of C. jejuni (and C. coli) changed drastically after exposure to imipenem (coccoid formation), meropenem (bulking and slight elongation), and sitafloxacin (marked elongation), and exhibited reduced motility. In the HEp-2 cell adherence model, unusually elongated bacteria were also observed for sitafloxacin. The data suggest that although resistance to antimicrobial agents (e.g., levofloxacin) has continuously been noted, carbapenems, sitafloxacin, and others such as beta-lactamase inhibitors alone showed good in vitro activity and that C. jejuni (and C. coli) demonstrated a unique ultrastructural nature related to high swimming motility and drug action.

Emergence of the community-acquired methicillin-resistant Staphylococcus aureus USA300 clone in a Japanese child, demonstrating multiple divergent strains in Japan.

In 2008 we isolated methicillin-resistant Staphylococcus aureus (MRSA) from an 11-month-old Japanese girl who lived in Saitama, Japan, and suffered from cellulitis of the lower thigh and sepsis. The MRSA (strain NN47) belonged to multilocus sequence type (ST) 8 and exhibited spa363 (t024), agr1, staphylococcal cassette chromosome mec (SCCmec) type IVa, and coagulase type III. It was positive for Panton-Valentine leukocidin (PVL) and the arginine catabolic mobile element (ACME). Pulsed-field gel electrophoresis (PFGE) demonstrated that the MRSA was the USA300 clone, which is the predominant community-acquired MRSA (CA-MRSA) in the US. Strain NN47 was divergent, in terms of the spa type and patterns of PFGE and plasmids, from the USA300-0114 type strain or USA300 strain NN36, previously isolated from a visitor (Indian girl) from the US. Strain NN47 was resistant to erythromycin, in addition to beta-lactam agents (e.g., oxacillin). These data demonstrate the first emergence of the USA300 clone in Japanese children who have never been abroad and have had no contact with foreigners (and therefore, the first USA300 spread in Japan), and also emergence of multiple divergent strains of the USA300 clone in Japan. Because the USA300 clone is highly transmissible and virulent, surveillance of the USA300 clone is needed.

Molecular typing of Campylobacter jejuni and C. coli from chickens and patients with gastritis or Guillain-Barré syndrome based on multilocus sequence types and pulsed-field gel electrophoresis patterns.

Campylobacter jejuni has recently been noted as the most common cause of bacterial foodborne diseases in Japan. In the present study, we determined ST types of C. jejuni and Campylobacter coli isolated from chickens and patients with enteritis or GBS in Japan and Thailand. C. jejuni from chickens, enteritis, and GBS exhibited divergent ST types and included several novel types in addition to worldwide common types. C. coli from enteritis was also divergent. Novel ST types may represent unidentified native clones in each country. Pulsed-field gel electrophoresis confirmed the above typing and demonstrated long-term persistence and transmission.