1.Physicochemical properties, molecular structure, antioxidant activity, and biological function of extracellular melanin from Ascosphaera apis.
Zhi LI ; Hui HENG ; Qiqian QIN ; Lanchun CHEN ; Yuedi WANG ; Zeyang ZHOU
Journal of Zhejiang University. Science. B 2022;23(5):365-381
Ascosphaera apis spores containing a dark-colored pigment infect honeybee larvae, resulting in a large-scale collapse of the bee colony due to chalkbrood disease. However, little is known about the pigment or whether it plays a role in bee infection caused by A. apis. In this study, the pigment was isolated by alkali extraction, acid hydrolysis, and repeated precipitation. Ultraviolet (UV) analysis revealed that the pigment had a color value of 273, a maximum absorption peak at 195 nm, and a high alkaline solubility (7.67%) and acid precipitability. Further chemical structure analysis of the pigment, including elemental composition, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, mass spectrometry, and nuclear magnetic resonance (NMR), proved that it was a eumelanin with a typical indole structure. The molecular formula of melanin is C10H6O4N2, and its molecular weight is 409 Da. Melanin has hydroxyl, carboxyl, amino, and phenolic groups that can potentially chelate to metal ions. Antioxidant function analyses showed that A. apis melanin had a high scavenging activity against superoxide, hydroxyl, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, and a high reducing ability to Fe3+. Indirect immunofluorescence assay (IFA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses showed that A. apis melanin was located on the spore wall. The spore wall localization, antioxidant activity, and metal ion chelating properties of fungal melanin have been suggested to contribute to spore pathogenicity. However, further infection experiments showed that melanin-deficient spores did not reduce the mortality of bee larvae, indicating that melanin does not increase the virulence of A. apis spores. This study is the first report on melanin produced by A. apis, providing an important background reference for further study on its role in A. apis.
Animals
;
Antioxidants/pharmacology*
;
Larva
;
Melanins
;
Molecular Structure
;
Onygenales
2.Mycological study of dermatophytosis in a part of South India
Raghavendra Rao Morubagal ; Rashmi Padmanabha Mahale ; Sowmya Govindanahalli Shivappa ; Tejashree Anantharajaurs ; Madhuri Kulkarni
Malaysian Journal of Microbiology 2017;13(1):1-5
Aims: Epidermophyton, Microsporum and Trichophyton are the genera of dermatophytes causing superficial mycoses.
These infections are on rise due to increase in immunocompromised patients and favorable environmental conditions
in countries like India. The present study was undertaken to identify dermatophytes causing superficial fungal infection
by microscopy and culture techniques which helps in accurate diagnosis and appropriate treatment of cases.
Methodology and results: Samples were collected from affected sites after cleaning the affected surface with 70%
alcohol. All samples were microscopically examined for presence of hyphal structures by digesting in 10% to 40% KOH
solution. All samples were inoculated into Sabouraud dextrose agar with chloramphenicol and Sabouraud dextrose
agar with cycloheximide and chloramphenicol and incubated at room temperature for four weeks. Tease mount
technique and slide culture technique were used for identification of dermatophytes. One hundred and ten samples
from clinically suspected dermatophytoses which includes 77(70%) from male and 33(30%) from female patients were
processed for identification of dermatophytes. Samples were subjected to microscopy and culture. In 61 samples
(54.54%) fungal hyphae were seen by direct microscopic examination (KOH). Fifty six samples (50%) yielded
dermatophyte growth in culture. Trichophyton rubrum was the predominant species isolated followed by T. violaceum
and T. mentagrophytes.
Conclusion, significance and impact of study: Accurate and rapid diagnosis of superficial fungal infection is
essential for proper management of cases. Direct microscopy is very good method for routine diagnosis, however
culture remains gold standard.
Arthrodermataceae
3.Dermatophytes Isolated From Korea.
Yeungnam University Journal of Medicine 1990;7(2):13-26
No abstract available.
Arthrodermataceae*
;
Korea*
4.Pseudo-Clubbing Complicated by Dermatophyte Onychomycosis.
Fan WU ; Jiao FENG ; Hong SANG
Annals of Dermatology 2014;26(2):271-273
No abstract available.
Arthrodermataceae*
;
Onychomycosis*
5.Microscopic Findings of Macroconidia in Microsporum canis.
Yong Woo CHOI ; Osung KWON ; Joonsoo PARK ; Yong Joon BANG
Korean Journal of Medical Mycology 2017;22(2):84-85
No abstract available.
Arthrodermataceae
;
Microsporum*
6.A Case of White Superficial Onychomycosis.
Korean Journal of Dermatology 1994;32(5):931-933
Clinical types of onychorpycosis, consist of distal subungual orychomycosis, white superficial onychomycosis, proximal subongual onychomycosis and candidal onychomycosis. White superficial onychomycosis aippears as white, sharply outlined areas on the surfaces of toenails. The fingernails are not affected. Trichophyton mentogrophytes, rarely Trichophyton rubrm, is the causa ive dermatophytes. The auther reports a case of white superficial onychomycosis of the fingernail caused by T. rubrm.
Arthrodermataceae
;
Nails
;
Onychomycosis*
;
Trichophyton
7.Identification of Dermatophytes by Mycological Tests and Random Amplified Polymorphic DNA analysis.
Jeong Aee KIM ; Sang Eun MOON ; Tae Eun KWON ; Hee Joon YU ; Baik Kee CHO ; Kwang Hoon LEE ; Kyu Joong AHN ; Jong Hyun YOON
Korean Journal of Dermatology 2001;39(2):168-175
BACKGROUND: Dermatophytes are usually identified based on their characteristic morphologies and physiological tests. However, identification is often delayed and problematic for atypical isolates. Recently, random amplified polymorphic DNA(RAPD) analysis was successfully performed for the identification of dermatophyes. OBJECTIVE: This study was performed to identify clinical isolates which could not be identified previously. The causes of unidentification were analysed and the merits and demerits of RAPD analysis were evaluated. METHODS: Thirty-six clinical isolates and 14 standard strains were included in this study. Seven mycological studies were performed and RAPD analysis was done by using primer OPAO-15 (5'-GAAGGCTCCC-3'). RESULTS: Based on the results of 7 mycological tests, 28 strains were confirmed as follows: 24, T. rubrum; 2, T. mentagrophytes; 2, T. raubitschekii. Four were considered as atypical strains of T. rubrum, and another 4 as non-dermatophytic moulds. This results were confirmed by RAPD analysis. CONCLUSION: RAPD analysis was useful for the identification of dermatophytes, especially the atypical strains. However, non-dermatophytic mould could not be identified by RAPD analysis. RAPD analysis was considered as a supplementary method to the conventional mycological studies for the identification of dermatophytes.
Arthrodermataceae*
;
DNA*
;
Mycology
8.The Epidemiology of Dermatophyte Infection in Southeastern Korea (1979~2013).
Sang Lim KIM ; Kyou Chae LEE ; Yong Hyun JANG ; Seok Jong LEE ; Do Won KIM ; Weon Ju LEE ; Yong Jun BANG ; Jae Bok JUN
Annals of Dermatology 2016;28(4):524-527
No abstract available.
Arthrodermataceae*
;
Epidemiology*
;
Korea*
9.The File Method to Detect the Causative Organisms of Tinea Unguium.
Jong Seok HWANG ; Soon Bong SUH
Korean Journal of Dermatology 1986;24(5):613-617
In order to increase the positive rate of cultre for dermatophyte infections of the nails, the authors devised the new file method. It is to perform the KOH mount arid culture with fine subungual hyperkeratotic debris obtained from the hyponycLium after grinding the nail plate from the surface to the bottom using various files, And we compared the result of this new method with that of conventional scraping and punch methods in 40 toenails and ]1 fingernails. The positive rate of culture for tinea unguium by three different methods was as follows: It was 52.5%(21 cases) through conventional scraping method, 70% (28 cases) through punch method and 80% (32 cases) through file method in the 40 toenai ls. lt was 18.2% (2 cases) through punch method, 27. 3% (3 sases) through scraping method and 54. 6%(6 cases) through file method in the 11'fingernails. In conclusion, the file method was found to be a more effective and successful method to detect the causative organisms of tinea unguium and was also easy to handle.
Arthrodermataceae
;
Nails
;
Onychomycosis*
;
Tinea*
10.Contamination of dermatophytes in the clothes of patients with tinea cruris.
Su Hee OH ; Soon Bong SUH ; Sung Hwa KIM ; Jae Bok JUN
Korean Journal of Dermatology 1991;29(5):610-615
No abstract available.
Arthrodermataceae*
;
Humans
;
Tinea*