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Kazutaka Fukushima

Publications and source records attributed to Kazutaka Fukushima.

18 recordsLinked to original sources

Antifungal susceptibility of epigallocatechin 3-O-gallate (EGCg) on clinical isolates of pathogenic yeasts.

This is the first report to investigate the antifungal susceptibility of 21 clinical isolates of seven Candida species to epigallocatechin 3-O-gallate (EGCg) and to compare with six antifungal agents, amphotericin B (AMPH), fluconazole (FLCZ), flucytosin (5FC), itraconazole (ITCZ), micafungin (MCFG), and miconazole (MCZ), using a method following the National Committee for Clinical Laboratory Standards (NCCLS) M27-A guidelines. Among the tested species, Candida glabrata exhibited the highest susceptibility to EGCg (MIC50, 0.5-1 microg/ml and MIC90, 1-2 microg/ml) compared favorably with FLCZ, although they were slightly less susceptible than to AMPH, 5FC, MCFG, ITCZ, and MCZ. Candida guilliemondii and Candida parapsilosis (MIC50, 1-4 microg/ml and MIC90, 2-16 microg/ml) were also susceptible to EGCg, although they appear to be slightly less susceptible to EGCg than C. glabrata and the other antifungal agents tested. Moreover, the susceptibility of Candida krusei strains (MIC50, 2 microg/ml and MIC90, 4-8 microg/ml) to EGCg was approximately 2- to 8-fold higher than those of 5FC and FLCZ. Our data indicate that EGCg can inhibit clinically pathogenic Candida species, although the concentrations of EGCg for antifungal susceptibility were slightly higher than those of tested antifungal agents on the whole. Based on these results, we suggest that EGCg may be effectively used as a possible agent or adjuvant for antifungal therapy in Candidiasis.

Amphotericin B↗

A new antifungal macrolide, eushearilide, isolated from Eupenicillium shearii.

In screening for antifungal substances, a new macrolide, eushearilide (1), was isolated from Eupenicillium shearii IFM54447. The structure of 1 was established to be 24-membered macrolide having a non-conjugated diene and a choline phosphate ester moetiy on the basis of detailed investigation of NMR, UV, IR and MS spectral data. Compound 1 showed antifungal activity against various fungi and yeasts, including human pathogens Aspergillus fumigatus, Trichophyton spp. and Candida spp.

Antifungal Agents↗

4-benzyl-3-phenyl-5H-furan-2-one, a vasodilator isolated from Malbranchea filamentosa IFM 41300.

Screening of Malbranchea filamentosa IFM 41300 for bioactive compounds led to the identification of 4-benzyl-3-phenyl-5H-furan-2-one (1) as a vasodilator and erythroglaucin (2). The structure of 1 was established on the basis of spectroscopic and chemical investigations. Compound 1 inhibited Ca2+-induced vasocintraction in aortic rings pretreated with high K+ (60mM) or norepinephrine. Finally, compound 1 did not exhibit activity against human pathogenic microorganisms.

Animals↗

A new hexose transporter from Cryptococcus neoformans: molecular cloning and structural and functional characterization.

We carried out a screen for Cryptococcus neoformans genes involved in resistance to copper ion toxicity and identified a new hexose transporter (Hxt) gene, HXT1. Hxt1 consists of 520 amino acids and functions to transport hexoses such as glucose. Although Hxt1 conferred copper resistance to Saccharomyces cerevisiae, disruption of the HXT1 gene showed that Hxt1 is not necessary for copper resistance. In virulence tests, an hxt1 mutant strain showed 12% less phenoloxidase activity than the wild-type strain, and no difference in the ability to form melanin was identified. In addition, the hxt1 mutant strain showed virulence similar to that of the wild-type strain in experiments with Caenorhabditis elegans. However, the hxt1 mutant strain generated larger capsules than were generated by the wild-type strain. Thus, Hxt1 appears to be involved in capsule formation.

Animals↗

Two new meroterpenoids, penisimplicin A and B, isolated from Penicillium simplicissimum.

In the course of our research for new antifungal agents, two new meroterpenoids, penisimplicin A (1) and B (2), were isolated from Penicillium simplicissimum. The absolute structures of 1 and 2 were established by spectroscopic and chemical investigation. Penisimplicin A (1) and B (2) are rare examples of D-ring seco-meroterpenoids. Since compounds 1 and 2 showed no antifungal activities, the isolation of the compounds with antifungal activity will be attempted.

Antifungal Agents↗

Identification of pathogenic dematiaceous fungi and related taxa based on large subunit ribosomal DNA D1/D2 domain sequence analysis.

The nucleotide sequences of the D1/D2 domains of large subunit (26S) ribosomal DNA for 76 strains of 46 species of pathogenic dematiaceous fungi and related taxa were determined. Intra-species sequence diversity of medically important dematiaceous fungi including Phialophora verrucosa, Fonsecaea pedrosoi, Fonsecaea compacta, Cladophialophora carrionii, Cladophialophora bantiana, Exophiala dermatitidis, Exophiala jeanselmei, Exophiala spinifera, Exophiala moniliae, and Hortaea werneckii were extremely small; as few as 0 changes were detected in C. bantiana, Fonsecaea and Exophiala species, 1 bp in C. carrionii and H. werneckii, and 2 bp in P. verrucosa. Inter-species nucleotide diversity between most species was higher. These data suggested that the D1/D2 domain is sufficiently variable for identification of pathogenic dematiaceous fungi and relevant species. The phylogenetic trees constructed from the sequence data revealed that most human pathogenic species formed a single cluster and that Cladosporium and Phialophora species were distributed polyphyletically into several clusters.

Ascomycota↗

New decalin derivatives, eujavanoic acids A and B, from Eupenicillium javanicum.

Two new decalin derivatives, eujavanoic acids A (1) and B (2), were isolated from Eupenicillium javanicum, along with several compactin derivatives. The structures of 1 and 2 were determined by spectroscopic methods and modified Mosher's method. The side chain (2-methylbutanoyloxy) and acid functionalities of compactin derivatives were necessary to show the antifungal activity.

Antifungal Agents↗

Specific oligonucleotide primers for identification of Cladophialophora carrionii, a causative agent of chromoblastomycosis.

Cladophialophora carrionii is one of the relatively common causative agents of chromoblastomycosis. We have developed the specific oligonucleotide primer set based on the internal transcribed spacer regions of ribosomal DNA for the rapid identification of this pathogen. PCR with this primer set amplified a 362-bp amplicon from C. carrionii strains. From other relevant dematiaceous species, including medically important dematiaceous fungi, such as Fonsecaea pedrosoi, Phialophora verrucosa, and Exophiala dermatitidis, and eight species of medically important yeasts, such as Candida albicans and Cryptococcus neoformans var. neoformans, the primer set did not produce any amplicon. PCR with this primer set may be a useful tool for the identification of C. carrionii.

Chromoblastomycosis↗

First case of Arthrographis kalrae ethmoid sinusitis and ophthalmitis in the People's Republic of China.

We present here the first case in the People's Republic of China of human disease caused by the fungus Arthrographis kalrae. The male patient had fungal panophthalmitis and invasive sinusitis involving the maxillary and ethmoid sinuses. He was an apparently healthy man before receiving trauma to his left eye. He complained of pain and loss of visual acuity in the injured eye, which displayed redness and edema and eventually discharged pus. His symptoms became more severe after he was treated with steroids and several antibacterial agents. A computed tomography scan of the left eye revealed that the maxillary and ethmoid sinuses were involved. A smear of purulent material from the left eye orbit revealed fungal elements, and cultures of the material grew a fungus. The isolate was identified as A. kalrae based on gross and microscopic morphologies, biochemical assays, and DNA sequence analysis. The patient received amphotericin B intravenously, itraconazole orally, and atomized allitridum by nebulizing allitridum therapy. The patient's wound healed following surgical intervention, but the patient lost the use of his left eye. This case should remind ophthalmologists and other clinicians to consider the possibility of infections being fungal when antibacterial agents have no effect and the patient's condition worsens.

Adult↗

A new nonadride derivative, dihydroepiheveadride, as characteristic antifungal agent against filamentous fungi, isolated from unidentified fungus IFM 52672.

In the screening of searching for new antifungal agents, a new nonaride compound, dihydroepiheveadride (1), was isolated from unidentified fungus IFM 52672 as the most potent antifungal principle from this organism. The structure of 1 was established on the basis of spectroscopic and chemical investigation, as well as detailed comparison of the spectroscopic and physico-chemical data of the oxidized derivative (3) from 1 with those of heveadride (2). Compound 1 showed strong antifungal activity against various filamentous fungi including human pathogens Aspergillus fumigatus, Penicillium marneffei and Trichophyton spp. It also showed the growth inhibition activity against certain human pathogenic yeasts such as Trichosporon species, while it had weak or no antifungal activity against Candida spp. and Cryptococcus neoformans, and no antibacterial activity against Bacillus subtilis nor against Escherichia coli. The antifungal potencies of compounds 2 and 3 were found to be weaker than that of 1.

Anhydrides↗

Specific oligonucleotide primers for identification of Hortaea werneckii, a causative agent of tinea nigra.

Hortaea werneckii, a black yeast-like hyphomycete that is widely distributed in tropical and subtropical environments, can cause superficial mycotic infection in humans. This fungus was recently isolated from superficial infectious lesions of a guinea pig in Japan. An oligonucleotide primer set specific for Hortaea werneckii was designed on the basis of the internal transcribed spacer regions of the ribosomal DNA (rDNA). Polymerase chain reaction (PCR) with this primer set yielded a 306 bp PCR amplicon from only H. werneckii. This primer set did not amplify DNAs of 42 other related dematiaceous species, including the medically important dematiaceous fungi Cladophialophora carrionii, Fonsecaea pedrosoi, Phialophora verrucosa, and Exophiala dermatitidis, and eight species of medically important yeasts, including Candida (C.) albicans, C. dublinensis, C. glabrata, C. parapsilosis, C. tropicalis, Cryptococcus neoformans var. neoformans, Malassezia furfur, and Trichosporon asahii var. asahii. PCR with this primer set may be a useful technique for rapid identification of H. werneckii.

Base Sequence↗

Rapid identification of the genus fonsecaea by PCR with specific oligonucleotide primers.

An oligonucleotide primer set based on internal transcribed spacer regions of ribosomal DNA for PCR which gives the amplicon for only the DNA from Fonsecaea species was designed. This set yielded an amplicon with 333 bp for all strains of Fonsecaea pedrosoi and Fonsecaea compacta examined but no amplicons for related dematiaceous fungi and pathogenic yeasts. PCR using this primer set was considered to be a useful method for the rapid identification of the genus FONSECAEA:

Ascomycota↗

The epidemiology and mating behavior of Arthroderma benhamiae var. erinacei in household four-toed hedgehogs (Atelerix albiventris) in Japan.

An epidemiological survey of Trichophyton mentagrophytes var. erinacei in the household hedgehog and other rodents was made between January 17, 2002 and February 28, 2002 in Japan. Quills and hairs were collected from sources identified via the internet. The fungus was isolated only from the quills of four-toed hedgehogs (7/18; 39%) from Kanto to Kyushu regions. Isolates were examined morphologically, physiologically and genetically, and identified as T. mentagrophytes var. erinacei anamorph. The isolates were also genetically compared with European hedgehog (Erinaceus europeus)-borne T. mentagrophytes var. erinacei and Kenyan hedgehog (Aterelix albiventris)-borne Arthroderma benhamiae, and their genotypes of the ITS1-5.8S-ITS2 rDNA were all identical. The isolates were crossed with A. benhamiae Americano-European race and African race, A. vanbreuseghemii and A. simii, with the result that they mated only with African race (+) or (-). Mating types of the isolates were (+) in 6 isolates and (-) in one. An intra-isolate mating between one of the 6 plus isolates and the minus one formed abundant mature gymnothesia, the mating type ratio of the F1 progeny was approximately 1:1, and the sib crossings of F1 progeny produced abundant fertile gymnothesia. The present study revealed that the intra-Japanese hedgehog-borne isolate crossing showed complete fertility and that the sexual degeneration pointed out by Takashio (Mycologia 71: 968-976, 1979) did not exist. Two pairs of mating, (+) and (-) mating types of Japanese isolates with (-) and (+) tester strains of A. benhamiae African race formed less gymnothesia, mating type ratios were unbalanced, and sib crossings of F1 progeny produced small gymnothesia containing a low number of asci, pseudogymothesia, or none, respectively. These results show that A. benhamiae var. erinacei, the teleomorph of T. mentagrophytes var. erinacei, belongs to a different mating group (e.g. hedgehog race) than the Americano-European and African races in A. benhamiae.

Animals↗

Effect of medium components and time of cultivation on chitin production by Mucor circinelloides (Mucor javanicus IFO 4570) -- a factorial study.

Chitin production of mycelia from Mucor circinelloides (Mucor javanicus) was studied with a two-level factorial design in all combinations of the following factors in the culture medium: time of cultivation, concentration of D-glucose, L-asparagine and thiamine. Chitin was characterised by infrared and nuclear magnetic resonance spectroscopy. The four factors showed statistically significant (95%) positive main effects on chitin production, without interactions between them. The highest chitin yield (23.9%) was obtained with the medium containing 60 g/l of glucose, 3 g/l of asparagine and 0.008 mg/l of thiamine and is comparable to the highest in the literature.

Asparagine↗

Identification of the first isolates of Trichosporon asahii var asahii from disseminated trichosporonosis in China.

Infection with Trichosporon asahii is a major cause of deep-seated and disseminated trichosporonosis, which is associated with a high mortality rate. Disseminated trichosporonosis in individuals with no underlying disease has not been reported. In this study, we report the identification of the first isolate of Trichosporon asahii var. asahii in China. Two isolates were obtained from the liver and skin of a patient with disseminated trichosporonosis who displayed no evidence of underlying disease. The morphologic and physiologic characteristics of the two isolates differed slightly from those of usual strains of T. asahii var. asahii, including the type strain CBS 2479. Ubiquinone-9 was identified as the major ubiquinone in both isolates. Sequence analysis of the LSUrDNA D1/D2, ITS, and IGS1 regions from the two isolates showed them to be T. asahii var. asahii, and random amplified polymorphic DNA analysis strongly suggested that they were the same strain.

Adult↗

The first isolation of Hortaea werneckii from a household guinea pig.

Hortaea werneckii, a black yeast and the causative agent of tinea nigra (a superficial type of dermatomycosis), is a human pathogen and is also found in the environment. It is not highly pathogenic but in the last fifteen to twenty years has been isolated from various human and environmental sources in Japan. As far as we know, there has been no report on the isolation of H. werneckii from animals. Recently, we found a case of a guinea pig with dark superficial lesions on the palm and dorsal areas. Cultural and morphological studies of scrapings from the lesion showed that the causative agent was a black yeast, which was identified as H. werneckii by morphological study and molecular biological screening. D1/D2 region of the 26S large subunit rDNA gene of this isolate was identical to those of 11 other H. werneckii isolates used as reference strains in this study. This is the first case recorded of tinea nigra caused by H. werneckii in a guinea pig.

Animals↗

An isolate of Arthroderma benhamiae with Trichophyton mentagrophytes var. erinacei anamorph isolated from a four-toed hedgehog (Atelerix albiventris) in Japan.

A female four-toed hedgehog probably imported from Africa and kept as a pet by a family suffered from depilation and mite (Caparinia tripilis) infection. Depilated quills were inoculated on a commercially available medium and an isolate of the dermatophytes was obtained. A giant colony after 14 days incubation on yeast extract Sabourauds agar had a central umbo with white granular surface and a yellow pigment ring in the reverse. The hedgehog isolate produced numerous elongated microconidia singly attached along the sides of hyphae. Macroconidia were somewhat irregular in shape and size and 2-6 septa. Abundant intermediate sized spores between micro- and macro conidia and few spirals were observed. Hair perforation and urease activity tests were positive. Maximum growth temperature was 40 C. In the mating tests using the tester strains of both African and Americano-European races of Arthroderma benhamiae, the strain produced numerous gymnothecia only when paired with the African race mating type minus(-). In addition, 591 bases of the internal transcribed spacer region of the ribosomal RNA gene including the 5.8S region (ITS1-5.8S-ITS2) were sequenced and corresponded to those of T. mentagrophytes var. erinacei (DDBJ/EMBL/GenBank accession numbers Z97996 and Z97997) by more than 99.7%. Therefore, our case is the first isolation of A. benhamiae with T. mentagrophytes var. erinacei anamorph in Japan.

Animals↗