In Vitro Antifungal Activity and Mode of Action of 2',4'-Dihydroxychalcone against Aspergillus fumigatus

2',4'-Dihydroxychalcone (2',4'-DHC) was identified from a heat shock protein 90 (Hsp90)-targeting library as a compound with Hsp90 inhibitory and antifungal effects. In the presence of 2',4'-DHC (8 microg/mL), radial growth of Aspergillus fumigatus was inhibited 20% compared to the control, and green pigmentation was completely blocked. The expression of the conidiation-associated genes abaA, brlA, and wetA was significantly decreased (approximately 3- to 5-fold) by treatment with 2',4'-DHC. The expression of calcineurin signaling components, cnaA and crzA, was also significantly reduced. The inhibitory effects of 2',4'-DHC on metabolic activity and mycelial growth were significantly enhanced by combination treatment with itraconazole and caspofungin. Docking studies indicated that 2',4'-DHC bind to the ATPase domain of Hsp90. These results suggest that 2',4'-DHC act as an Hsp90-calcinurin pathway inhibitor.

The Bioconversion of Red Ginseng Ethanol Extract into Compound K by Saccharomyces cerevisiae HJ-014

A beta-glucosidase producing yeast strain was isolated from Korean traditional rice wine. Based on the sequence of the YCL008c gene and analysis of the fatty acid composition, the isolate was identified as Saccharomyces cerevisiae strain HJ-014. S. cerevisiae HJ-014 produced ginsenoside Rd, F2, and compound K from the ethanol extract of red ginseng. The production was increased by shaking culture, where the bioconversion efficiency was increased 2-fold compared to standing culture. The production of ginsenoside F2 and compound K was time-dependent and thought to proceed by the transformation pathway of: red ginseng extract-->Rd-->F2-->compound K. The optimum incubation time and concentration of red ginseng extract for the production of compound K was 96 hr and 4.5% (w/v), respectively.

Expression and Activity of Catalases Is Differentially Affected by GpaA (Ga) and FlbA (Regulator of G Protein Signaling) in Aspergillus fumigatus

Vegetative growth signaling of the opportunistic human pathogenic fungus Aspergillus fumigatus is mediated by GpaA (Galpha). FlbA is a regulator of G protein signaling, which attenuates GpaA-mediated growth signaling in this fungus. The flbA deletion (DeltaflbA) and the constitutively active GpaA (GpaA(Q204L)) mutants exhibit enhanced proliferation, precocious autolysis, and reduced asexual sporulation. In this study, we demonstrate that both mutants also show enhanced tolerance against H2O2 and their radial growth was approximately 1.6 fold higher than that of wild type (WT) in medium with 10 mM H2O2. We performed quantitative PCR (qRT-PCR) for examination of mRNA levels of three catalase encoding genes (catA, cat1, and cat2) in WT and the two mutants. According to the results, while levels of spore-specific catA mRNA were comparable among the three strains, cat1 and cat2 mRNA levels were significantly higher in the two mutants than in WT. In particular, the DeltaflbA mutant showed significantly enhanced and prolonged expression of cat1 and precocious expression of cat2. In accordance with this result, activity of the Cat1 protein in the DeltaflbA mutant was higher than that of gpaA(Q204L) and WT strains. For activity of the Cat2 protein, both mutants began to show enhanced activity at 48 and 72 hr of growth compared to WT. These results lead to the conclusion that GpaA activates expression and activity of cat1 and cat2, whereas FlbA plays an antagonistic role in control of catalases, leading to balanced responses to neutralizing the toxicity of reactive oxygen species.

Molecular Identification of Two Strains of Phellinus sp. by Internal Transcribed Spacer Sequence Analysis

Two species of cultivated Phellinus sp. were identified as P. baumii by internal transcribed spacer (ITS) sequence analysis. The fruit bodies of the examined strains were similar to those of naturally occurring strains, having a bracket-like form, yellow-to-orange color, and poroid hymenial surfaces. The DNA sequences of ITS region of both strains showed a homology of 99% with ITS1 to ITS2 sequences of P. (Inonotus) baumii strain PB0806.

Possible Roles of LAMMER Kinase Lkh1 in Fission Yeast by Comparative Proteome Analysis

To investigate the possible roles of LAMMER kinase homologue, Lkh1, in Schizosaccharomyces pombe, whole proteins were extracted from wild type and lkh1-deletion mutant cells and subjected to polyacrylamide gel electrophoresis. Differentially expressed proteins were identified by tandem mass spectrometry (MS/MS) and were compared with a protein database. In whole-cell extracts, 10 proteins were up-regulated and 9 proteins were down-regulated in the mutant. In extracellular preparations, 6 proteins were up-regulated in the lkh1 + null mutant and 4 proteins successfully identified: glycolipid anchored surface precursor, beta-glucosidase (Psu1), cell surface protein, glucan 1,3-beta-glucosidase (Bgl2), and exo-1,3 beta-glucanase (Exg1). These results suggest that Lkh1 is involved in regulating cell wall assembly.

The Treatment Outcome of Hypopharynx Cancer : Surgery versus Organ Preservation Therapy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Hypopharynx cancer usually presents with late stage diseases requiring radical resection including total laryngectomy with reconstruction resulting in severe functional deficits. In order to preserve organ function, chemotherapy in combination with radiotherapy was introduced and it showed similar treatment. The aim of this study is to compare the treatment outcomes of surgery and organ preservation therapy. SUBJECTS AND METHOD: A retrospective review of 55 patients who were diagnosed with hypopharynx cancer and underwent curative treatment from 1994 to 2006 was performed. Patients who underwent surgery or surgery plus postoperative radiotherapy were assigned to surgical treatment group and patients who underwent radiotherapy or radiotherapy with chemotherapy were assigned to organ preservation therapy group. RESULTS: Surgical treatment group consisted of 29 patients (52.7%) and organ preservation therapy group consisted of 26 patients (47.3%). The overall 5 year survival rate was 34%. The survival rate was decreased significantly according to the N stage (p=0.02). There was no statistically significant difference in 5 year survival rates between the two groups. The larynx preservation rate was 35.8% for the organ preservation therapy group and 44% for the conservation surgery group. CONCLUSION: Treatment of hypopharynx cancer could be individualized according to the status of diseases.

Sinonasal and Psychological Symptoms in Rhinologic Patients(SNOT-20 & SCL-90-R) / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Quality of life is one of the important issues in the treatment of patients with chronic diseases of the nose and sinuses. Psychological disturbance may affect patient's symptoms and the outcome after treatments. In this study, we aimed to evaluate both sinonasal and psychological profiles in rhinologic patients. SUBJECTS AND METHOD: From February 2007 to January 2008, 117 rhinologic patients who had been scheduled for the nasal and sinus surgery were enrolled. They were divided into two groups, nasal cavity disease (NCD, n=53) and chronic rhinosinusitis (CRS, n=64). Somatic and psychological symptoms were evaluated using the Sinonasal Outcome Test-20 (SNOT-20) and Symptom Checklist-90-Revised (SCL-90-R). All of the patients underwent nasal endoscopy, computed tomography, acoustic rhinometry, T&T olfactometry and allergic skin prick test. RESULTS: Global severity index of the SCL-90-R was within the normal range for all the rhinologic patients. There was no difference of SNOT-20 (p=0.220) and SCL-90-R (p=0.367) scores between the two groups. In the non-allergic patients, the CRS group had higher scores of SNOT-20 (p=0.002) and SCL-90-R (p=0.003) compared to the NCD group. The allergic NCD patients showed significantly higher scores of SNOT-20 (p=0.020) and SCL-90-R (p=0.003) compared to non-allergic NCD patients. CONCLUSION: Allergy could augment the patient's somatic and psychological symptoms, especially in the NCD group. Therefore, allergy control may be important in the management of patients with nasal cavity diseases if they have allergic rhinitis.

Biodegradation of 2,4,6-Trinitrotoluene by White-Rot Fungus Irpex lacteus

White-rot fungus Irpex lacteus degraded TNT significantly in proportion to the culture time. After 48 h incubation, about 95% of TNT was degraded. Two reduced metabolites were identified as 4-amino-2,6-dinitrotoluene (4-ADNT) and 2-amino-4,6-dinitrotoluene (2-ADNT) which was further degraded.

Identification of Some Phellinus spp

Four strains of Phellinus spp. was identified based on internal transcribed spacer (ITS) region of rDNA sequence analysis and morphological characteristics. Basidiocarps of all strains were effused-reflexed and hymenial surface was poroid. Hyphal system was dimitic and basidiospore was globose to ellipsoid. The amplification of ITS regions produced a DNA fragment of 500 to 780 bp in all strains examined. The determined sequences were analyzed for the reconstruction of phylogenetic tree. From these results, Phellinus sp. KM-1, KM-2, and KM-4 was identified as P. hartigii, P. baumii, and P. linteus, respectively.