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Background: Mucormycosis is a rare form of invasive, rapidly progressive and lethal opportunistic fungal infection caused by Mucorales. Although Rhizopus arrhizus (R. arrhizus) is the most commonly isolated Mucorales worldwide, infections caused by Apophysomyces variabilis (A. variabilis) are increasing. Objectives and Methods: We present a case of necrotizing fasciitis caused by A. variabilis in an immunocompetent woman. In order to further understand the characteristics of the strain isolated from the patient, we identified the strain through ITS sequencing, assessed the ability to tolerate salt concentrations and temperature conditions, in addition to performing in vitro drug susceptibility testing against common antifungal agents. Results: The strain showed 98.76% identity with A. variabilis in the NCBI database, and it was found to tolerate higher temperatures and salt concentrations than previously reported strains. The strain was sensitive to amphotericin B and posaconazole, but not to voriconazole, itraconazole, 5‐fluorocytosine and echinocandins. Conclusions: This case indicates that Mucorales caused by A. variabilis should be recognised as an emerging pathogen that can cause a high mortality rate in the absence of prompt diagnosis and proper treatment in China, aggressive surgical debridement combined with prompt and appropriate antifungal treatment may improve outcomes. [ABSTRACT FROM AUTHOR]

Talaromyces (Penicillium) marneffei (T. marneffei) is a thermally dimorphic fungus that can cause opportunistic systemic mycoses. Our previous study demonstrated that concomitant use of berberine (BBR) and fluconazole (FLC) showed a synergistic action against FLC-resistant T. marneffei (B4) in vitro. In this paper, we tried to figure out the antifungal mechanisms of BBR and FLC in T. marneffei FLC-resistant. In the microdilution test, the minimum inhibitory concentration (MIC) of FLC was 256 μg/ml before FLC and BBR combination, and was 8 μg/ml after combination, the partial inhibitory concentration index (FICI) of B4 was 0.28. After the treatments of BBR and FLC, the studies revealed that (i) increase reactive oxygen species (ROS), (ii) reduce ergosterol content, (iii) destroy the integrity of cell wall and membrane, (iv) decrease the expression of genes AtrF, MDR1, PMFCZ, and Cyp51B however ABC1 and MFS change are not obvious. These results confirmed that BBR has antifungal effect on T. marneffei, and the combination with FLC can restore the susceptibility of FLC-resistant strains to FLC, and the reduction of ergosterol content and the down-regulation of gene expression of AtrF, Mdr1, PMFCZ, and Cyp51B are the mechanisms of the antifungal effect after the combination, which provides a theoretical basis for the application of BBR in the treatment of Talaromycosis and opens up new ideas for treatment of Talaromycosis. [ABSTRACT FROM AUTHOR]

Tinea nigra is a superficial fungal infection usually caused by Hortaea werneckii (H. werneckii). We report a special case of tinea nigra in an immunocompetent child who developed a unilateral, rapidly growing pigmented lesion on her palm. Interestingly, Curvularia lunata (C. lunata) was isolated from the lesion scrapes and was identified by both morphological features and molecular biology methods. The lesion was completely cleared by topical naftifine hydrochloride and ketoconazole cream. We present—to the best of our knowledge—the first case of tinea nigra where the causative pathogen was identified as C. lunata. We therefore provide a brief literature review of previously reported cases of tinea nigra to broaden the knowledge of the potential causative pathogens. The etiology, demography, clinical features, diagnostic methods, and treatment of the reviewed cases are summarized and analyzed. [ABSTRACT FROM AUTHOR]

This study analyzed the in vitro drug sensitivity of Cryptococcus spp. from Guangxi, Southern China. One hundred three strains of Cryptococcus were recovered from 86 patients; 14 were HIV positive and 72 were HIV negative. Ninety-two strains were identified as Cryptococcus neoformans var. grubii , while 11 strains were identified as Cryptococcus gattii (5 C. gattii sensu stricto and 6 Cryptococcus deuterogattii). The recovered strains were tested against commonly used antifungal drugs (fluconazole, amphotericin B, 5-fluorocytosine, itraconazole, and voriconazole) and to novel antifungal drugs (posaconazole and isavuconazole) using CLSI M27-A4 method. The results showed that all isolates were susceptible to most antifungal drugs, of which the minimum inhibitory concentration (MIC) ranges were as follows: 0.05–4 μg/ml for fluconazole, 0.25–1 μg/ml for amphotericin B; 0.0625–2 μg/ml for 5-fluorocytosine, 0.0625–0.25 μg/ml for itraconazole, 0.0078–0.25 μg/ml for voriconazole, 0.0313–0.5 μg/ml for posaconazole, 0.0020–0.125 μg/ml for isavuconazole for C. neoformans var. grubii isolates, and 1–16 μg/ml for fluconazole, 0.125–1 μg/ml for 5-fluorocytosine, 0.25–1 μg/ml for amphotericin B, 0.0625–0.25 μg/ml for itraconazole, 0.0156–0.125 μg/ml for voriconazole, 0.0156–0.25 μg/ml for posaconazole, and 0.0078–0.125 μg/ml for isavuconazole for C. gattii isolates. Furthermore, some C. neoformans var. grubii isolates were found to be susceptible-dose dependent to 5-fluorocytosine and itraconazole. In addition, a reduction in the potency of fluconazole against C. gattii is possible. We observed no statistical differences in susceptibility of C. neoformans var. grubii and C. gattii in the tested strains. Continuous observation of antifungal susceptibility of Cryptococcus isolates is recommended to monitor the emergence of resistant strains. [ABSTRACT FROM AUTHOR]

Talaromyces marneffei is a common cause of infection in immunocompromised patients in Southeast Asia and Southern China. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the cytotoxic processes of the host immune system and grow inside host macrophages. These mechanisms that allow T. marneffei to survive macrophage-induced death are poorly understood. In this study, we examined the role of a calcineurin homolog (cnaA) from T. marneffei during growth, morphogenesis and infection. Deletion of the cnaA gene in T. marneffei resulted in a strain with significant defects in conidiation, germination, morphogenesis, cell wall integrity, and resistance to various stressors. The Δ cnaA mutant showed a lower minimal inhibitory concentration (MIC) against caspofungin (16 μg/ml to 2 μg/ml) and micafungin (from 32 μg/ml to 4 μg/ml) compared with the wild-type. These results suggest that targeting calcineurin in combination with echinocandin treatment may be effective for life-threatening systemic T. marneffei infection. Importantly, the cnaA mutant was incapable of adapting to the macrophage environment in vitro and displayed virulence defects in a mouse model of invasive talaromycosis. For the first time, a role has been shown for cnaA in the morphology and pathogenicity of a dimorphic pathogenic filamentous fungus. [ABSTRACT FROM AUTHOR]

Knowledge about the clinical and laboratory characteristics and prognosis of Talaromyces marneffei infection in children is limited. A retrospective study was conducted on pediatric patients with disseminated T. marneffei infection in a clinical setting. Extracted data included demographic information (age and sex), clinical features, laboratory findings, treatment, and prognosis. Eleven HIV-negative children were enrolled. The male/female ratio was 8:3. The median age of onset was 17.5 months (3.5–84 months). The mortality rate in these children was 36.36% (4/11). Seven children had underlying diseases. All of the children had multiple immunoglobulin abnormalities and immune cell decline. Ten children received voriconazole treatment, and most of the children (7/10) had a complete response to therapy at primary and long-term follow-up assessment; only three children died of talaromycosis. One patient recovered from talaromycosis but died of leukemia. The child who received itraconazole treatment also showed clinical improvement. No adverse events associated with antifungal therapies were recorded during and after the treatment. Talaromycosis is an indicator disease for undiagnosed severe immunodeficiencies in children. Awareness of mycoses in children by pediatricians may prompt diagnosis and timely treatment. Voriconazole is an effective, well-tolerated therapeutic option for disseminated T. marneffei infection in non-HIV-infected children. [ABSTRACT FROM AUTHOR]

Talaromyces (Penicillium) marneffei can cause fatal disseminated infection in immunocompromised hosts. However, therapeutic strategies for the mycosis are limited. Reports of the other fungi suggest that berberine, a component of traditional herb, inhibitors interact with antifungal agents to improve the treatment outcomes. In the study, we evaluated the in vitro efficacy of berberine in combination with conventional antifungal agents against the pathogenic yeast form of T. marneffei. We demonstrate the synergistic effect of combination of berberine with fluconazole (52.38%), itraconazole (66.67%), voriconazole (71.43%), amphotericin B (71.43%) or caspofungin (52.38%) of T. marneffei strains, respectively. Time–kill curves confirmed the synergistic interaction, and no antagonistic was observed in all of the combinations. In conclusion, berberine could enhance the efficacy of conventional antifungal agents against the yeast form of T. marneffei in vitro. The results indicated berberine might have a potential role in combination therapy for talaromycosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Intracellular calcium overload has been implicated in various pathological conditions including ischemia reperfusion injury. This study aims to explore the effect and probable mechanism of dantrolene, a ryanodine receptor and intracellular calcium antagonist, on the skeletal muscle ischemia reperfusion injury. MATERIALS AND METHODS: SD rats were randomly divided into three groups: sham group which underwent anaesthesia and exposure of femoral vein, reperfusion group that received 2 h ischemia and the amount of diluent via femoral vein before 4 h reperfusion, dantrolene group that underwent 2 h ischemia and was given 2 mg/kg dantrolene via femoral vein before 4 h reperfusion. The parameters measured at the end of reperfusion included serum maleic dialdehyde (MDA), tissue myeloperoxidase (MPO) and muscle histology, as well as serum TNF-α and IL-10. RESULTS: Levels of MDA, MPO and TNF-α increased in the reperfusion group, whereas the relevant expressions in the dantrolene group decreased significantly. Histological examination demonstrated significant improvements between the same both groups. IL-10 reflected the protection observed above with a significant up-regulation of expression after dantrolene administration. CONCLUSION: Ryanodine receptor antagonist dantrolene exerted a significant protective effect against the inflammatory injury of skeletal muscle ischemia reperfusion. The underlying molecular mechanism is probably related to the suppression of TNF-α levels and the increment of IL-10 expression. [ABSTRACT FROM AUTHOR]

[ Objective ]This research was aimed to investigate the antibacterial activity in vitro induced by water extracts of the Holly Bark combined with antibacterial agents to provide references for the comprehensive development and utilization of Holly Bark. [ Method ]The minimal inhibition concentration (MIC) of water extracts of Holly Bark and antibacterial agents were tested through twice micro-dilution method. Extended spectrum beta-lactamases (ESBLs) bacterial were induced and subcultured by the 1/2MIC of water extracts of Holly Bark combined with antibacterial agents. Fractional inhibitory concentration (FICI) indexes of extracts combined with antibacterial agents were determined by microdilution checkerboard techniques. [ Result ]The MIC of water extracts of Holly bark was 1.0 g/mL. The MIC of ESBLs-producing bacterial decreased significantly after inducing by 0.5g/mL of water extracts of Holly Bark combined with 6 antibacterial agents, such as amoxicillin, levofloxacin, clinafloxacin, sulfamonomethoxine, gatifloxacin, ceftiofur sodium. FICI indexes were 0.375, 0.750, 0.750, 0.515, 0.750 and 0.750, respectively. [ Conclusion ] Antibacterial activities of antibacterial agents against ESBLs-producing bacterial are enhanced significantly by water extracts of Holly Bark, showing additive effect or synergistic activity correlation. [ABSTRACT FROM AUTHOR]

Cuprous iodide (CuI) is the ultrafastest inorganic scintillation crystal at present. But the low intensity of its ultrafast component luminescence limits the wide application of CuI at room temperature. In this paper, the photoluminescence (PL) characteristics of different quality CuI crystals before and after annealing in various conditions have been investigated in terms of peak position and peak intensity. The origin of different emission band peaked around 426 nm, 680 nm, 718 nm and 820 nm is discussed and the excitation spectra of two mainly emission bands is obtained. Meanwhile, the relative peak intensity of the ultrafast luminescence component to slow lumiescence component of CuI crystals has been studied with respect to the defect concentration of I vacancies. Especially, the method of improving the intensity of ultrafast compentent luminescence of CuI crystals is concluded. These results can provide an important reference for optimizing the luminescence performance of CuI crystals. [ABSTRACT FROM AUTHOR]

A Ni/Ta bilayer is deposited on n-type 6H–SiC and then annealed at different temperatures to form an ohmic contact. The electrical properties are characterized by I–V curve measurement and the specific contact resistance is extracted by the transmission line method. The phase formation and microstructure of the Ni/Ta bilayer are studied after thermal annealing. The crystalline and microstructure properties are analyzed by using glance incident x-ray diffraction (GIXRD), Raman spectroscopy, and transmission electron microscopy. It is found that the transformation from the Schottky to the Ohmic occurs at 1050 °C and the GIXRD results show a distinct phase change from Ta2C to TaC at this temperature. A specific contact resistance of 6.5× 10−5 Ω·cm2 is obtained for sample Ni(80 nm)/Ta(20 nm)/6H–SiC after being annealed at 1050 °C. The formation of the TaC phase is regarded as the main reason for the excellent Ohmic properties of the Ni/Ta contacts to 6H–SiC. Raman and TEM data reveal that the graphite carbon is drastically consumed by the Ta element, which can improve the contact thermal stability. A schematic diagram is proposed to illustrate the microstructural changes of Ni/Ta/6H–SiC when annealed at different temperatures. [ABSTRACT FROM AUTHOR]

Al-doped ZnO thin film (AZO) is used as a subcontact layer in 6H–SiC photoconductive semiconductor switches (PCSSs) to reduce the on-state resistance and optimize the device structure. Our photoconductive test shows that the on-state resistance of lateral PCSS with an n+-AZO subcontact layer is 14.7% lower than that of PCSS without an n+-AZO subcontact layer. This occurs because a heavy-doped AZO thin film can improve Ohmic contact properties, reduce contact resistance, and alleviate Joule heating. Combined with the high transparance characteristic at 532 nm of AZO film, vertical structural PCSS devices are designed and their structural superiority is discussed. This paper provides a feasible route for fabricating high performance SiC PCSS by using conductive and transparent ZnO-based materials. [ABSTRACT FROM AUTHOR]

The RCA-cleaned 6H-SiC surface has a 1 nm native oxide layer, which was directly observed by high-resolution transmission electron microscopy and confirmed by energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The surface band bending caused by the native oxide layer was studied by synchrotron radiation photoelectron spectroscopy. The binding energy of Si 2p core level for the Ni/oxygen-free SiC interface showed almost zero shift (<0.07 eV). However, it red-shifted about 0.34 eV for the Ni/native-oxide/SiC interface, it indicated that negative charged interface states induced in the Ni/native-oxide interface resulted in the upward bending of the interface energy band. [ABSTRACT FROM AUTHOR]