红色毛癣菌表型稳定性研究

为探讨红色毛癣菌表型的稳定性,所有菌株采用沙堡琼脂试管培养基(SDA)培养。菌株鉴定及分型依据菌落的特征及色素,大小分生孢子的形态,尿素酶试验和毛发穿孔试验。对近期临床分离的10株红色毛癣菌和1株标准株,间隔4周传代1次,共传4次。207株红色毛癣菌共分离出4个表型,其中绒毛型占首位(45.4%),沟纹型(24.1%),羊毛型(20.8%),粉末型(9.7%),未见颗粒型。保存1年后207株有54株发生形态变异,变异率为26.1%,沟纹型变异最小,相对稳定。11株红色毛癣菌传代后菌落形态或色素发生变异。红色毛癣菌表型不稳定,保存和传代后的菌落形态或产色均易发生变异;沟纹型变异率最低。     

传代对红色毛癣菌表型和核糖体基因影响的研究

目的通过对传代前后红色毛癣菌表型和核糖体基因的分析,探讨传代对表型变异和核糖体基因的影响。方法采用传统方法鉴定原代及传代后的5株红色毛癣菌临床菌株及1株标准菌株;对原代及20代的菌株核糖体保守区(5.8S和ITS2)和非转录间隔区(NTS)进行PCR扩增和基因测序,比较原代与传代后表型及核糖体基因有无变化。结果红色毛癣菌菌株在传代过程中发生多次表型变异,且变异可逆转。同一菌株的原代与20代PCR扩增指纹图一致,基因序列亦基本一致,其中20代标准株菌株在TRS-1区可见个别碱基的突变。结论红色毛癣菌传代过程中表型极易发生变异和逆转,而核糖体基因相对稳定。     

琼脂稀释法检测6种药物抗皮肤癣菌MIC

本试验用琼脂稀释法测定了29株皮肤癣菌对两性霉素B、5-氟胞嘧啶、伊曲康唑、咪康唑、克霉唑和环吡酮胺的MIC值。材料和方法受试菌种：须癣毛癣菌12株，红色毛癣菌4株，紫色毛癣菌1株，断发毛癣菌1株，石膏样小孢子菌2株，犬小孢子菌7株，絮状表皮癣菌2株。须癣毛癣菌所有菌株均为临床分离的菌株，纯化后结合菌落和显微镜下特征鉴定菌种。     

开远地区10年浅部真菌及病原菌种类分析

目的为掌握开远地区的浅部真菌病情况及病原菌菌种分布特点。方法对临床拟诊浅部真菌病的患者3358人次，取标本行10％KOH涂片镜检、分离培养及菌种鉴定。分析浅部真菌病的发病情况。结果直接涂片查见菌丝和／或孢子的2249份，阳性率67％。培养出真菌1356株，阳性率40．4％。其中红色毛癣菌754株、须癣毛癣菌154株、念珠菌210株、犬小孢子菌62株、铁锈色小孢子菌104株、石膏样小孢子菌18株、疣状毛癣菌14株、玫瑰色毛癣菌2株、紫色毛癣菌2株、断发毛癣菌4株。结论开远地区的浅部真菌病病原菌以红色毛癣菌为优势菌，其次为念珠菌，再次为须癣毛癣菌。     

吉林省15年浅部真菌病菌种分析

目的：了解15年1986年－2001年吉林省浅部真菌病的致病菌及菌种变迁情况，指导临床预防治疗。方法：用沙堡琼脂培养基分离培养15年吉林省浅部真菌病的致病菌，并动态分析各年龄菌种分离结果。结果：共分离出8种2763株致病菌，其中红色毛癣菌居首位，须癣毛癣菌居第2位，犬小孢子菌居第3位。在头癣病原菌中，犬小孢子菌由80年代的84．3％逐渐减少，至90年代后期仅占9．6％。而红色毛癣菌则逐年增高。在其他各病种中，红色毛癣菌及絮状表皮癣菌逐年增高，犬小孢子菌则逐年减少。结论：15年吉林省浅部真菌病致病菌种有明显变迁，尤其犬小孢子菌随年龄明显减少为显著特征。     

红色毛癣菌和须癣毛癣菌的PCR指纹分析

红色毛癣菌和须癣毛癣菌的传统鉴别主要依据培养形态、生理生化等方法,但红色毛癣菌的菌落产红现象受培养基类型、 pH、培养温度等因素的影响 [1],我们应用 PCR方法,以微小卫星 DNA引物,对这 2种癣菌的基因组 DNA进行扩增,可以在很短时间内把它们区分开来。 泳道 1为 Markerλ DNA/EcoRⅠ＋ HindⅢ,泳道 2、 7、 8、 9为红色毛癣菌,泳道 3～ 6为须癣毛癣菌 图 1 (GACA)4作引物的 PCR扩增结果 一、材料与方法 (一 )实验菌株：本研究采用红色毛癣菌临床分离株 23株 ,须癣毛癣菌临床分离株 11株。红色毛癣菌中 11株来自上海…     

136例股癣发病情况及菌种分析

目的：分析兰州一综合医院分离的股癣病原菌种方法：对临床拟诊为股癣的患者，取标本行10％KOH涂片镜检、分离培养及菌种鉴定：结果：临床拟诊为股癣的169例患者（同时合并足癣者56例）真菌镜检阳性136例（80．47％）；培养分离菌株125株，红色毛癣菌112株（89．60％）、念珠菌9株（7．20％），其中包括白念珠菌8株（6．40％）、近平滑念珠菌1株（0．80％），行膏样毛癣菌4株（3．20％）：结论：肥胖成年男性易患股癣；足癣是股癣的重要传染源；兰州地区股癣主要致病菌为红色毛癣菌。     

足癣和甲癣中分离的须癣毛癣菌与红色毛癣菌的溶蛋白活力

须癣毛癣菌(Tm)和红色毛癣菌(Tr)是人类最常见的皮肤癣菌,能侵入并消化角蛋白。在培养基中,这些真菌能利用角蛋白作为碳和氮源,生长良好。然而,其侵袭和消化角质结构的方式还不清楚。作者分别观察了足癣和甲癣病人中分离的Tm和Tr于含角蛋白层颗粒琼脂培养基中的生长情况,研究了从42例足癣或甲癣分离的Tm和Tr在葡萄糖蛋白胨琼脂上传代后的溶蛋白活力。     

红色毛癣菌随机扩增DNA多态性分型研究

红色毛癣菌(Trichophyton rubrum)是皮肤癣菌中最常见的病原菌,我国大多数地区的检出率在30%以上^[1],传统的表型分型法将其分为五型,但是,由于红色毛癣菌大多数为不典型株,而且传代过程中表型特征可发生转变或丧失,因此,表型分型的不稳定性导致它不能准确反映红色毛癣菌的遗传特征。我们应用随机扩增DNA多态性(RAPD)分析法对46株分别从广州、香港、雅加达(印尼)3个城市浅部真菌感染患者获得的红色毛癣菌进行DNA分型,对三地红色毛癣菌的表型特征与基因型别关系进行了初步探讨。     

BCG-MSG培养基鉴定几种常见的丝状真菌

目的　寻找一种鉴定丝状真菌的新培养基。方法　选择常见的 6种皮肤癣菌和申克孢子丝菌 ,采用自行配制的溴甲酚绿奶粉葡萄糖琼脂培养基 (BCG MSG)培养 ,并与马玲薯葡萄糖琼脂和沙堡弱琼脂两种培养基的菌落形态进行比较 ,在 5天、7天、14天记录色素的形成情况 ,总观察时间为 14天。结果　红色毛癣菌在BCG MSG上产色快 ,其他皮肤癣菌色素变化不大 ,只是色素比较鲜艳。结论　BCG MSG培养基具有产色效果好而快 ,直观感好和配制简单等特点 ,值得推广应用。     

氮掺杂碳纳米酶联合近红外光抗真菌体外试验研究

目的：评价氮掺杂碳纳米酶（N-Carbon nanozyme）联合近红外光对白念珠菌和红色毛癣菌体外抗菌的效果。方法：将白念珠菌和红色毛癣菌标准菌株常规接种培养，分别分为四组：(1)空白对照组：真菌不作任何处理；(2)光照组：真菌予以2.5 W/cm2近红外光照射8 min；（3）材料组：真菌予以250 μg/mL的N-Carbon nanozyme处理30 min；（4）实验组：真菌予以250 μg/mL的N-Carbon nanozyme及2.5 W/cm2近红外光照射8 min。SYTO 9/PI染色判断白念珠菌和红色毛癣菌的菌体活性；扫描电镜观察和平板计数法判定白念珠菌抗菌形态和菌落形成单位（CFU）的数量。结果：实验组中SYTO9/PI染色示红色荧光染色信号显著增加；与空白对照组比较，光照组、材料组间菌落数均未见明显差异，而实验组可见菌落明显减少。生物扫描电镜显示白念珠菌的细胞形态发生明显的变化。结论：氮掺杂碳纳米酶联合近红外光对白念珠菌及红色毛癣菌均有明显的抑制作用。     

Molecular strain typing of Trichophyton rubrum indicates multiple strain involvement in onychomycosis

BACKGROUND: Trichophyton rubrum is an important cause of onychomycosis. Molecular strain typing methods have recently been developed to address questions of epidemiology and source of relapse following treatment. OBJECTIVES: To determine whether T. rubrum nail infections are caused by one or more strains of this fungus. METHODS: Nail specimens from 10 patients with onychomycosis due to T. rubrum were cultured and five colonies per culture plate were selected for molecular strain typing. DNA was extracted from these isolates and subjected to a polymerase chain reaction-based typing method that analyses variations in numbers of repetitive elements in the non-transcribed spacer region of the ribosomal RNA gene repeats. RESULTS: In six of 10 specimens, there were two or more T. rubrum strain types present. CONCLUSIONS: This preliminary study suggests that in many cases of fungal nail infection by T. rubrum, multiple strains are involved. This has important implications for epidemiological studies and possibly for therapy.     

红色毛癣菌基因型与表型的研究

目的 探讨红色毛癣菌基因型与表型、侵犯部位及其来源地区的相关性.方法 基因分型采用ITS区域探针与DNA印迹杂交法,表型分型采用传统方法.结果 所试49株红色毛癣菌(南京21株、大连26株、北京2株)分为20型(A-T型),其中A型9株均为大连株;B型9株中7株为南京株;C型6株均为南京株.5种表型除颗粒型外其他4型均有A型,17株绒毛型和7株沟纹型B型占居首位,6株羊毛型和17株粉末型A型占居首位.分离自甲癣的21株以C型为主;股癣10株和体癣6株以A型为主;足癣8株,B型占居首位;头癣4株G型占居首位.结论 红色毛癣菌基因型与表型、侵犯部位及其来源地区可能具有一定的相关性.     

Species identification and strain differentiation of dermatophyte fungi using polymerase chain reaction amplification and restriction enzyme analysis

BACKGROUND: Standard biochemical tests, microscopy, colony characteristics, and mating tests have conventionally been used for the identification of dermatophytes species, but these methods of identification are costly, time-consuming, and require special skills. OBJECTIVE: Our purpose was to identify a method that enables rapid species identification and strain differentiation of dermatophyte fungi. METHODS: We chose 4 restriction enzymes (BsYiI, DdeI, HinfI, and MvaI) that could produce different fragment patterns after enzyme digestion according to species or strain. We performed enzyme digestions after polymerase chain reaction amplification of internal transcribed spacer region and identified different restriction fragment length polymorphisms (RFLP) according to species and strains. RESULTS: All the species included in this study could be easily differentiated using any combination of 2 different restriction enzymes except Trichophyton rubrum and T raubitschekii, which produced identical digestion patterns after all 4 restriction enzyme digestions. In the case of T mentagrophytes, MvaI and DdeI each produced 2 distinct RFLP patterns. CONCLUSION: This study showed that internal transcribed spacer region analysis using polymerase chain reaction-RFLP through DdeI and MvaI is useful for rapid identification of the majority of dermatophytes species. However, there were 2 different band patterns by DdeI and MvaI restriction enzyme digestion and no correlations between morphologic types and RFLP patterns in T mentagrophytes.     

PCR and PCR-RFLP techniques targeting the DNA topoisomerase II gene for rapid clinical diagnosis of the etiologic agent of dermatophytosis

BACKGROUND: We have focused on the DNA topoisomerase II genes of several pathogenic fungi, and developed polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) methods targeting this gene for identification of dermatophytes. OBJECTIVE: To assess the availability of the PCR-based identification for an etiologic study of dermatophytosis, by testing these PCR and PCR-RFLP methods for stability and reproducibility. METHODS: Three hundred and fifty-six dermatophyte strains were isolated from 305 patients with tinea, and their genomic DNAs were used as templates for the PCR using primer mixes (PsT, PsME, dPsD1 or dPsD2) composed of gene-specific primers for identification of dermatophytes to the species level. The genomic DNAs of Trichophyton rubrum were further subjected to subrepeat element analysis of the nontranscribed spacer (NTS) of ribosomal DNA (rDNA). RESULTS: In this study, six dermatophyte species (T. rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans, Microsporum canis, Microsporum gypseum, and Epidermophyton floccosum) were obtained. In all cases, the identifications obtained from the PCR and PCR-RFLP targeting the DNA topoisomerase II gene coincided with those from the conventional morphological features-based identification technique. The sensitivity of the PCR-based identification was found to be a colony of approximately 3mm in diameter. Furthermore, T. rubrum was divided into three groups (17 types) on the basis of the sizes and numbers of the products generated from the TRS-1 region, and three types from the TRS-2 region. CONCLUSION: The PCR and PCR-RFLP targeting the DNA topoisomerase II gene were rapid, stable, and reproducible for species identification of dermatophytes, and thus are convenient tools for an etiologic study of dermatophytosis.     

Detection of xanthomegnin in epidermal materials infected with Trichophyton rubrum

Xanthomegnin, a mutagenic mycotoxin best known as an agent of nephropathy and death in farm animals exposed to food-borne Penicillium and Aspergillus fungi, was first isolated about 35 y ago as a diffusing pigment from cultures of the dermatophyte, Trichophyton megninii. This study investigates the production of xanthomegnin by the most common dermatophytic species, Trichophyton rubrum, both in dermatologic nail specimens and in culture. In view of the labile nature of xanthomegnin, a chromatographic procedure was developed to allow high-performance liquid chromatography analysis within 1 h of sample extraction. In cultures, Tricho- phyton rubrum produced xanthomegnin as a major pigment that appears to give the culture its characteristic red colony reverse. Xanthomegnin was also repeatedly extracted from human nail and skin material infected by Trichophyton rubrum. The level of xanthomegnin present, however, varied among the clinical samples studied. Xanthomegnin was not detected in uninfected nails. These results show that patients with Trichophyton rubrum infections may be exposed to xanthomegnin, although the consequences of such an exposure are not currently known.     

武汉地区甲真菌病的致病菌及菌种变迁分析

目的了解1999年1月~2005年12月武汉地区甲真菌病的致病菌种分布及变迁情况。方法对1999年1月~2005年12月甲真菌病患者的真菌培养资料1237例进行系统分析总结。结果真菌培养阳性895例,阳性率72.4%。致病菌中,皮肤癣菌559株(61.1%),酵母菌287株(31.4%),霉菌69株(7.5%)。皮肤癣菌中红色毛癣菌占95.0%(531/559),酵母菌中念珠菌属占71.8%(206/287),霉菌中曲霉属占53.6%(37/69);混合感染20例占2.2%。结论武汉地区甲真菌病的致病菌中以皮肤癣菌为主,其中红色毛癣菌为优势菌种,但是占致病菌的比例下降;酵母菌属和念珠菌属的比例上升;霉菌中以曲霉属和镰刀菌属为主。甲真菌病混合感染的比例上升。     

临床疑诊甲真菌病1036例真菌学分析

目的　了解近 5年本院甲真菌病病原菌的种类和构成 ,观察流行病学特点。方法　对近 5年临床疑诊的10 3 6例甲真菌病患者的真菌学实验室检查情况进行系统分析、总结。结果　共培养出真菌 63 1株 ,其中酵母菌占49.60 % ,以克柔念珠菌、红酵母、近平滑念珠菌为主 ;皮肤癣菌占 2 1.71% ,主要菌种为须癣毛癣菌和红色毛癣菌 ;其他丝状真菌占 19.81% ,主要菌种为曲霉和青霉 ;污染真菌占 8.87%。结论　本院近 5年甲真菌病患者病原菌依次为酵母菌、皮肤癣菌、其他丝状真菌 ,排前 5位的真菌分别是须癣毛癣菌 (11.2 5 % ) ,克柔念珠菌 (10 .14 % ) ,红酵母 (9.98% ) ,红色毛癣菌 (9.5 1% ) ,曲霉 (8.87% )。     

Trichophyton raubitschekii: a new agent of dermatophytosis in Brazil?

A microbiological and ultrastructural study of Trichophyton raubitschekii recovered from a patient with tinea faciei is presented. This is the second case of isolation of this fungus in Sao Paulo and the sixth case in Brazil. Upon culture, the morphological pattern and the physiological tests performed confirmed the identification of T. raubitschekii. The ultrastructural study of T. raubitschekii showed the presence of a membrane-like structure located in the outer portion of the hyphal walls. This structure was bi-stratified and very like the one observed in T. rubrum. Is T. raubitschekii a new fungus emerging in Brazil or is it a T. rubrum variant?