Inhibitory effects of ultrasound irradiation on Staphylococcus epidermidis biofilm.

PURPOSE: We aimed to investigate whether low-intensity continuous and pulsed wave ultrasound (US) irradiation can inhibit the formation of Staphylococcus epidermidis biofilms, for potential application in the treatment of catheter-related bloodstream infections (CRBSI). METHODS: S. epidermidis biofilms that formed on the bottom surfaces of 6-well plates were irradiated on the bottom surface using the sound cell incubator system for different intervals of time. RESULTS: US irradiation with continuous waves for 24 h notably inhibited biofilm formation (p < 0.01), but the same US irradiation for 12 h had no remarkable effect. Further, double US irradiation with pulsed waves for 20 min inhibited biofilm formation by 33.6%, nearly two-fold more than single US irradiation, which reduced it by 17.9%. CONCLUSION: US irradiation of a lower intensity (ISATA = 6-29 mW/cm2) than used in a previous study and lower than recommended by the Food and Drug Administration shows potential for preventing CRBSI caused by bacterial biofilms.

Doxorubicin Embedded into Nanofibrillated Bacterial Cellulose (NFBC) Produces a Promising Therapeutic Outcome for Peritoneally Metastatic Gastric Cancer in Mice Models via Intraperitoneal Direct Injection.

Natural materials such as bacterial cellulose are gaining interest for their use as drug-delivery vehicles. Herein, the utility of nanofibrillated bacterial cellulose (NFBC), which is produced by culturing a cellulose-producing bacterium (Gluconacetobacter intermedius NEDO-01) in a medium supplemented with carboxymethylcellulose (CMC) that is referred to as CM-NFBC, is described. Recently, we demonstrated that intraperitoneal administration of paclitaxel (PTX)-containing CM-NFBC efficiently suppressed tumor growth in a peritoneally disseminated cancer xenograft model. In this study, to confirm the applicability of NFBC in cancer therapy, a chemotherapeutic agent, doxorubicin (DXR), embedded into CM-NFBC, was examined for its efficiency to treat a peritoneally disseminated gastric cancer via intraperitoneal administration. DXR was efficiently embedded into CM-NFBC (DXR/CM-NFBC). In an in vitro release experiment, 79.5% of DXR was released linearly into the peritoneal wash fluid over a period of 24 h. In the peritoneally disseminated gastric cancer xenograft model, intraperitoneal administration of DXR/CM-NFBC induced superior tumor growth inhibition (TGI = 85.5%) by day 35 post-tumor inoculation, compared to free DXR (TGI = 62.4%). In addition, compared with free DXR, the severe side effects that cause body weight loss were lessened via treatment with DXR/CM-NFBC. These results support the feasibility of CM-NFBC as a drug-delivery vehicle for various anticancer agents. This approach may lead to improved therapeutic outcomes for the treatment of intraperitoneally disseminated cancers.

A Case of Recalcitrant Phaeohyphomycosis of the Face Caused by Exophiala lecanii-corni.

We describe a case of recalcitrant phaeohyphomycosis caused by Exophiala lecanii-corni, which was previously reported as Exophiala jeanselmei, infection. A 63-year-old Japanese woman presented with a 15-year history of multiple pruritic erythematous patches and plaques on the face. Histopathological examination and fungal culture revealed phaeohyphomycosis by E. jeanselmei. The attempted treatments included 6 g/day 5-flucytosine (5-FC), 100 mg/day itraconazole (ITCZ), and local hyperthermia. 5-FC was effective initially, but the patient deteriorated after discontinuation. Subsequently, she was referred to our hospital. Histopathological examination showed granuloma with multinucleated giant cells with infiltrating fungal hyphae in the dermis. The causative fungus was finally identified as E. lecanii-corni by ribosomal RNA gene analysis. The patient improved after receiving 200 mg/day ITCZ orally for 15 months with local hyperthermia. In the present case, we confirmed the identification of E. lecanii-corni as the causative agent by molecular methods. We also emphasize the importance of combination therapy with antimycotic agents and local hyperthermia in phaeohyphomycosis.

Genetic response to low­intensity ultrasound on mouse ST2 bone marrow stromal cells.

Although low­intensity ultrasound (LIUS) is a clinically established procedure, the early cellular effect of LIUS on a genetic level has not yet been studied. The current study investigated the early response genes elicited by LIUS in bone marrow stromal cells (BMSCs) using global­scale microarrays and computational gene expression analysis tools. Mouse ST2 BMSCs were treated with LIUS [ISATA, 25 mW/cm2 for 20 min with a frequency of 1.11 MHz in a pulsed­wave mode (0.2­s burst sine waves repeated at 1 kHz)], then cultured for 0.5, 1 and 3 h at 37˚C. The time course of changes in gene expression was evaluated using GeneChip® high­density oligonucleotide microarrays and Ingenuity® Pathway Analysis tools. The results were verified by reverse transcription­quantitative polymerase chain reaction (RT­qPCR). A single exposure of LIUS did not affect cell morphology, cell growth or alkaline phosphatase activity. However, 61 upregulated and 103 downregulated genes were identified from 0.5 to 3 h after LIUS treatment. Two significant gene networks, labeled E and H, were identified from the upregulated genes, while a third network, labeled T, was identified from the downregulated genes. Gene network E or H containing the immediate­early genes FBJ osteosarcoma oncogene and early growth response 1 or the heat shock proteins heat shock protein 1a/b was associated mainly with the biological functions of bone physiology and protein folding or apoptosis, respectively. Gene network T containing transcription factors fos­like antigen 1 and serum response factor was also associated with the biological functions of the gene expression. RT­qPCR indicated that the expression of several genes in the gene networks E and H were elevated in LIUS­treated cells. LIUS was demonstrated to induce gene expression after short application in mouse ST2 BMSCs. The results of the present study provide a basis for the elucidation of the detailed molecular mechanisms underlying the cellular effects of LIUS.

Low-intensity pulsed ultrasound promotes the expression of immediate-early genes in mouse ST2 bone marrow stromal cells.

PURPOSE: The effects of low-intensity pulsed ultrasound (LIPUS) on the expression of immediate-early genes (IEGs) in bone marrow stromal cells (BMSCs) were evaluated to elucidate the early cellular response to LIPUS. METHODS: Mouse ST2 BMSCs were treated with LIPUS (ISATA, 12-34 mW/cm2 for 20 min), then cultured at 37 °C. The expression levels of four IEGs (Fos, Egr1, Jun, and Ptgs2) and ERK1/2, a mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK), were assessed using real-time quantitative PCR and Western blot analyses, respectively. RESULTS: A single exposure of LIPUS at an intensity of 25 mW/cm2 significantly and transiently increased the expression levels of all four IEGs, and the peak expression was detected at 30-60 min after LIPUS stimulation. LIPUS exposure also significantly increased the phosphorylation level of ERK1/2. U0126, an inhibitor of MAPK/ERK, significantly prevented LIPUS-induced expression of Fos and Egr1, but not that of Jun and Ptgs2. On the other hand, treatment of the cells with LIPUS did not affect cell growth or alkaline phosphatase activity, a marker of osteoblast differentiation. CONCLUSION: These results suggest that LIPUS exposure significantly induces expression of IEGs such as Fos and Egr1 via the MAPK/ERK pathway in ST2 BMSCs.

Trichophyton tonsurans-induced kerion celsi with decreased defensin expression and paradoxically increased interleukin-17A production.

We report a case of kerion celsi due to Trichophyton tonsurans. An 18-year-old male student judo practitioner had alopecic patches, black dots and subcutaneous abscesses on the right temporal region. The damaged hair represented endothrix infection with T. tonsurans, as assessed by mycological examinations. He was treated with oral itraconazole without any therapeutic effect, followed by terbinafine with good effect. A skin biopsy showed neutrophil, lymphocyte and histiocyte infiltration into the dermis and subcutaneous tissue with abscesses around a number of dilated hair follicles. Immunostaining showed that the expression level of human ß-defensin 2 (HBD-2) was decreased in the epidermis of the alopecic and adjacent skin. Because interleukin (IL)-17A generally induces HBD-2 production by epidermal keratinocytes, we also immunohistochemically investigated IL-17A expression. Unexpectedly, many IL-17A-bearing cells were found around destructed hair follicles, indicating that IL-17A expression was not attenuated, but rather increased in the skin lesion. Our case suggests that IL-17A-upregulated antimicrobial peptide expression is disordered in kerion celsi, and severe inflammation with IL-17A may cause tissue damage and resultant scar.

Nerve alterations showing autophagy in 2 patients with lichen aureus.

Lichen aureus is a rare, chronic, persistent purpuric dermatosis clinically characterized by striking yellow- to bronze-colored lesions. Histologically, lichen aureus differs from other pigmented purpuric dermatoses in containing dense, band-like infiltrates closely associated with the epidermis. This report describes 2 patients with lichen aureus, a 20-year-old woman with a lesion on her right arm and a 51-year-old man with a lesion on the right side of his groin. Skin biopsy specimens revealed almost identical findings in both patients, including dense band-like infiltrates containing lymphocytes, histiocytes with hemosiderin deposits scattered extravasated red blood cells and nerve alterations at the dermo-epidermal interface. The nerves within the lesions were filled with granules, which stained positive with antibody to microtubule-associated protein 1A/1B-light chain 3, suggesting autophagy within the nerves. These altered nerves were present only in areas of band-like dermal lymphocytic infiltration. Electron microscopy of the lesions showed the accumulation of autophagosomes in Schwann cells.

A Case of Cutaneous Mycosis Caused by Scedosporium dehoogii on an Immunocompromised Patient.

This report describes a 77-year-old man with cutaneous mycosis caused by Scedosporium dehoogii while taking oral betamethasone and tacrolimus for the treatment of rheumatoid arthritis. At examination in our clinic, the patient had multiple cystic lesions and nodules with slight tenderness, varying in size up to 4 cm, on his left knee and shin. He had not noticed any traumatic injury at the site of the lesions. Fungal cultures of samples taken from the abscesses, scales, and crusts of the lesions yielded white, later grayish brown, fluffy surfaced colonies. Partial sequencing of the ß-tubulin gene confirmed the species of the isolate. The patient was initially treated with oral voriconazole and local hyperthermia, but experienced hepatic injury 2 weeks later. His treatment was changed to itraconazole (ITC) and local hyperthermia, followed by a combination of ITC and terbinafine. The patient recovered completely during the 12-month course of treatment.

Design of flexible polyphenylene proton-conducting membrane for next-generation fuel cells.

Proton exchange membrane fuel cells (PEMFCs) are promising devices for clean power generation in automotive, stationary, and portable applications. Perfluorosulfonic acid (PFSA) ionomers (for example, Nafion) have been the benchmark PEMs; however, several problems, including high gas permeability, low thermal stability, high production cost, and environmental incompatibility, limit the widespread dissemination of PEMFCs. It is believed that fluorine-free PEMs can potentially address all of these issues; however, none of these membranes have simultaneously met the criteria for both high performance (for example, proton conductivity) and durability (for example, mechanical and chemical stability). We present a polyphenylene-based PEM (SPP-QP) that fulfills the required properties for fuel cell applications. The newly designed PEM exhibits very high proton conductivity, excellent membrane flexibility, low gas permeability, and extremely high stability, with negligible degradation even under accelerated degradation conditions, which has never been achieved with existing fluorine-free PEMs. The polyphenylene PEM also exhibits reasonably high fuel cell performance, with excellent durability under practical conditions. This new PEM extends the limits of existing fluorine-free proton-conductive materials and will help to realize the next generation of PEMFCs via cost reduction as well as the performance improvement compared to the present PFSA-based PEMFC systems.

Glycyrrhetinic acid inhibits contact hypersensitivity induced by trichophytin via dectin-1.

Trichophyton infection is highly prevalent and tends to be recurrent. Therefore, it is important to develop new therapeutic agents. Previously, we established a mouse model of Trichophyton-induced contact hypersensitivity (CHS) and demonstrated that dectin-1 was involved in inflammation induced by trichophytin, the Trichophyton antigen. Here, we used that model to investigate glycyrrhetinic acid (GA) from plants of the genus Glycyrrhiza as a potential anti-inflammatory agent against superficial mycoses. GA suppressed swelling and the expression of inflammatory cytokines, including macrophage inflammatory protein (MIP)-2, interleukin (IL)-6, tumor necrosis factor (TNF)-α and interferon (IFN)-γ mRNA. Anti-MIP-2 antibody suppressed trichophytin-induced inflammation, and antidectin-1 antibody suppressed zymosan-induced MIP-2 production in keratinocyte cells. These results suggest that MIP-2 is produced by dectin-1 activation and is involved in inflammation associated with CHS to trichophytin. GA also suppressed zymosan-induced MIP-2 and interleukin (IL)-8, production in mouse and human macrophages and keratinocytes. Furthermore, GA suppressed the phosphorylation of spleen tyrosine kinase (Syk) and inhibitor of nuclear factor-kappa B (IκBα) and the degradation of IκBα in zymosan-simulated RAW264.7 cells. The results of this study suggest that GA suppresses inflammation induced by trichophytin, partly by the downregulation of Syk phosphorylation.

Case of dermatophyte abscess caused by Trichophyton rubrum: a case report and review of the literature.

A 54-year-old Japanese man without apparent immunosuppression presented with nodules with purulent drainage on the right lower leg. He had ringworm of the right leg and tinea unguium. A biopsy specimen of the nodule showed intradermal abscesses with fungal elements, and Trichophyton rubrum was cultured from both the pus and the biopsy specimen. Treatment with oral terbinafine resolved the nodules. Dermatophyte abscess is a rare, deep and invasive dermatophytosis, which is often associated with immunocompromised conditions. We provide a review of the literature including Japanese cases.

Active induction of in vivo microbubbles by acoustic radiation force at the bifurcation of blood vessel and its evaluation.

Alhough the development of drug delivery system using microbubbles and ultrasound is expected, because microbubbles diffuse in bloodstream, we have so far reported our attempts for active control of the microbubbles in flow by acoustic radiation force in order to increase local concentration of the microbubbles. However, there was no evidence that in vivo microbubbles act as similar as in vitro experiments, because there were limitations for reproduction of in vivo conditions. In this study, we have elucidated the relationship between brightness variation and microbubbles concentration in the suspension to estimate the absolute concentration in an invisible condition considering in vivo experiment. Then we conducted an experiment of active induction of microbubbles in a Y-form bifurcation of artificial blood vessel, where experimental conditions were with focused ultrasound, the central frequency of 5 MHz, flow velocity of 30 mm/s, and maximum sound pressure of 300 kPa-pp, respectively. Then we applied the conditions for active induction of in vivo microbubbles to compare with in vitro experiments. We used a bifurcation of blood vessel in an ear of a rabbit because the bifurcation shape in its blood vessel is visible. As the results of the experiment, the microbubbles concentration in the induced path was almost two times higher than that in the other path, which agrees with the results from in vitro experiments.

[Phaeomycotic cyst caused by Exophiala xenobiotica in a patient with rheumatoid arthritis and lung cancer].

In black fungal infections, Exophiala species are frequently encountered as causative agents of human mycosis, particularly in immunocompromised patients. Among them, Exophiala jenselmei was previously reported as the most common etiological agent. Advances in molecular taxonomy proved this taxon to be heterogeneous, and led to newly introduced or redefined species. Exophiala xenobiotica is one of the novel species differentiated from E. jenselmei on the basis of molecular phylogeny.Here, we report a case of pheomycotic cyst caused by E. xenobiotica, which was well controlled via drainage and local thermotherapy. A 70-year-old man developed a cystic nodular lesion on the dorsum of his right thumb over the previous 3 months. He had been treated with prednisolone and methotrexate for 4 years for rheumatoid arthritis. The patient also had lung cancer with vertebral bone metastasis. Direct microscopic examination of the greenish pus aspirated from the cyst revealed mycelial elements. Culture of the pus on blood and Sabouraud dextrose agar yielded numerous black colonies multiple times. Histopathological examination of a biopsy specimen showed subcutaneous abscess formation surrounded by granulomatous tissues. Faintly pigmented pseudohyphae were seen within the abscess. The presence of melanin in the fungal cells was determined by Fontana-Masson staining. Initial microscopic examination of the isolate revealed annellidic conidiogenous cells, suggestive of E. jenselmei. This strain was further identified as E. xenobiotica by sequence analysis of the internal transcribed spacer (ITS) region of ribosomal RNA, showing a 100% sequence homology with the strain type.Pheomycotic cysts should be considered on identifying a slowly developing chronic subcutaneous abscess in immunocompromised patients. Sequencing is recommended for accurate species identification of causative pathogens.

Control of a thin catheter bending at bifurcation points in artificial blood vessel by using acoustic radiation force.

In this paper, control of a thin catheter bending by using acoustic radiation force was carried out to develop precise and noninvasive surgery in small blood vessel. First, it was elucidated that the acting force to a thin catheter made from perfluoroalkoxy (PFA) copolymer could be obtained from the cantilever equation in the effective range, where the displacement of the catheter divided by the cube of the length of the catheter was less than 1.0×10(-5) mm(-2). Next, under the above cantilever theory, acoustic radiation force acting to the catheter was measured in the condition of the continuous ultrasound radiation. Furthermore, it was observed that the force depended on the ultrasound frequency. We confirmed that the force was obtained in the practical condition by the experiment and controlled it bending in artificial blood vessel including multiple bifurcations. It was suggested that the therapy using thin catheter and ultrasound is fully promising.