茄病镰刀菌致小腿慢性溃疡1例报告及病原真菌超微结构的研究

报道1例55岁男性农民,因右小腿溃疡4个月余就诊。取其溃疡组织作真菌培养和病理检查,真菌培养在含氯霉素、放线菌酮和不含氯霉素、放线菌酮的沙堡弱培养基中27℃都长出白色棉絮状菌落,而在不含氯霉素、放线菌酮条件下生长更好;在马玲薯培养基中长出镰刀状大分生孢子,菌种鉴定为茄病镰刀菌。8d后从溃疡处再取标本培养仍为茄病镰刀菌生长。病理切片经银染色后发现念珠状分隔菌丝,用透射电镜对病变组织内的菌体形态进行了超微结构研究。予伊曲康唑口服治疗,但患者未复诊而失访。     

两性霉素B和伏立康唑对临床真菌的体外抗菌活性分析

目的比较两性霉素B和伏立康唑对临床真菌的体外抗菌活性。方法用两性霉素B和伏立康唑的E-test条对分离自临床标本的116株真菌进行体外药敏试验,其中热带念珠菌15株,光滑念珠菌14株,近平滑念珠菌11株,克柔念珠菌6株,新生隐球菌8株,阿萨希毛孢子菌9株,烟曲霉29株,黄曲霉15株,黑曲霉1株,镰刀菌属7株,根霉属1株,以ATCC22019光滑念珠菌为质控菌株。结果两性霉素B对阿萨希毛孢子菌、镰刀菌、黄曲霉的MIC90均为64μg/ml,对其余受试菌株的MIC90均≤1μg/ml,伏立康唑对镰刀菌的MIC90为64μg/ml,对大部分受试菌株的MIC90均≤2μg/ml。结论除对某些真菌可能无效外,两性霉素B和伏立康唑可能适用于治疗大多数的真菌感染。     

少见尖端赛多孢子菌致脑组织感染1例及系列研究

目的报道尖端赛多孢子菌脑脓肿感染1例,并探讨真菌的鉴定及其对抗真菌药物体外药敏试验。方法取患者颅内引流物标本进行真菌培养和形态学鉴定,对分离菌做基因测序和抗真菌药物体外药敏试验。结果根据菌株的形态学特点和基因测序结果鉴定为尖端赛多孢子菌,药敏试验显示对两性青霉素B、氟康唑耐药,对伏立康唑敏感。结论尖端赛多孢子菌导致的真菌感染较少见,其鉴定主要依靠形态学特征和基因分析。伏立康唑对该菌株有较好的治疗作用。     

茄病镰刀菌致皮肤透明丝孢霉病1例

目的报告1例茄病镰刀霉引起的皮肤透明丝孢霉病。方法从患者皮损取材作真菌镜检、培养及组织病理学检查。结果直接镜检及组织病理切片均发现真菌菌丝,3次培养均为同一菌株生长。镜下可见大分生孢子基部细胞短、钝圆,小分生孢子呈假头状着生,可见厚壁孢子。根据以上形态学特征鉴定为茄病镰刀菌。结论对于透明丝孢霉病应早期诊断,并进行体外抗真菌药物的敏感试验,明确并有效控制基础疾病。     

红斑肢痛症继发尖孢镰刀菌感染1例

报道红斑肢痛症继发尖孢镰刀菌感染1例。患者男,9岁。双小腿、双足间歇性红肿、热、痛2a,双下肢起脓疱、溃疡20d。溃疡部位脓液真菌培养为尖孢镰刀菌。患者经口服特比萘芬和局部治疗,溃疡愈合,真菌清除。     

5例真菌性鼻窦炎临床及实验研究

目的报道5例丝状真菌所致真菌性鼻窦炎病例。方法分析5例鼻窦炎患者临床资料,对患者鼻分泌物或鼻黏膜进行真菌直接镜检和培养,对培养获得菌株进行形态学和分子生物学鉴定。结果结合真菌直接镜检、培养和分子生物学方法,确定致病真菌为茄病镰刀菌、烟曲霉、黄曲霉、波氏假阿利什霉和萝卜镰刀菌。4例患者采用鼻内窥镜手术治疗,1例患者采用伏立康唑、两性霉素B控制病情,效果均良好。结论真菌性鼻窦炎致病真菌多样,分子生物学可做准确鉴定,鼻内镜手术治疗效果良好。     

儿童不典型黄癣1例报告及文献复习

报告1例由许兰毛癣菌(Trichophyton schoenleinii)引起的儿童不典型黄癣,患儿临床症状轻微,缺乏蜡黄色、碟形黄癣痂和特殊的鼠臭味等典型临床症状.病发真菌直接镜检见大量不规则菌丝,间生膨大,大小不等、形态不规则的孢子,真菌培养为许兰毛癣菌生长,经分子生物学测序鉴定证实.E-test药敏结果显示伊曲康唑、两性霉素B、卡泊芬净及伏立康唑均敏感.经口服伊曲康唑胶囊及外用2％舍他康唑乳膏治疗基本痊愈.     

尖端赛多孢子菌引起急性髓性白血病患者多重感染的诊断研究

目的探讨尖端赛多孢子菌及细菌引起急性髓性白血病患者多重感染的诊断方法和治疗措施。方法连续采集患者左侧腹股沟分泌物或坏死组织行真菌和细菌培养,同时对阴茎冠状沟和包皮做病原菌检查;采用法国生物梅里埃公司VITEK-2全自动微生物分析仪对细菌进行鉴定和药敏试验;根据真菌培养的菌落特点和镜下形态鉴定致病真菌,采用MIC方法进行真菌体外药敏试验。结果抗真菌治疗前患者左侧腹股沟分泌物连续4次行真菌培养,均检测出尖端赛多孢子菌,体外药敏试验显示对伏立康唑有较低的MIC值。结论尖端赛多孢子菌的感染少见,且难治疗,极易感染免疫低下的患者合并细菌引起多重感染;及时进行分离、培养、鉴定和药物敏感性试验,及早进行病原学诊断,正确选用抗菌药物是治疗成功与否的关键。     

骨髓移植患者血流混合感染阿萨希毛孢子菌及棒状大孢酵母1例

患者,女,40岁,患骨髓增生异常综合征。患者骨髓移植术后,反复发热,血培养显示,血流混合感染2株真菌。18S核糖体RNA(18S rRNA)测序结果显示,其中1株真菌为阿萨希毛孢子菌,另1株真菌为棒状大孢酵母。两株真菌为罕见真菌,均对伏立康唑敏感。因鉴定及药敏时间较长,患者未等调整合理抗真菌药物,因持续中性粒细胞缺乏及真菌血症死亡。该病例是国内首次报道血液病患者血流混合感染阿萨希毛孢子菌和棒状大孢酵母。     

肺部及中枢神经系统尖端赛多孢子菌感染1例并文献复习

报道我院收治尖端赛多孢子菌致肺部及中枢神经系统感染1例,并探讨其治疗措施。取患者肺泡灌洗液、脑脊液、颅内引流物进行病原学培养及宏基因组二代基因检测,根据菌株的形态学特点和基因测序结果鉴定为尖端赛多孢子菌。手术引流及伏立康唑抗真菌治疗效果明显,但仍需进一步随访。     

Screening of microorganisms for biodegradation of poly(lactic-acid) and lactic acid-containing polymers.

The ability of some microorganisms to use lactic acid stereocopolymers and copolymers with glycolic acid as sole carbon and energy sources was studied under controlled or natural conditions. First, 14 filamentous fungal strains were tested in liquid cultures, adopting total lactic acid consumption, nitrogen source exhaustion, and maximal biomass production as selection criteria. Two strains of Fusarium moniliforme and one strain of Penicillium roqueforti were able to totally assimilate DL-lactic acid, partially soluble racemic oligomers (MW = 1,000), and the nitrogen source. Only one strain of F. moniliforme was able to grow on a poly(lactic acid)-glycolic acid copolymer (MW = 150,000) after 2 months of incubation at 28 degrees C on synthetic agar medium. Mycelium development was examined by scanning electron microscopy. F. moniliforme filaments were observed to grow not only at the copolymer surface but also through the bulk of the copolymer. In a second approach, plates made of a racemic poly(lactic acid) were buried in the soil before being incubated in petri dishes containing mineral agar medium under controlled conditions. Five strains of different filamentous fungi were isolated, and their ability to assimilate racemic poly(lactic acid) oligomers was tested in liquid cultures.     

抗菌肽Fengycins抑制串珠镰刀菌的初步机制

Fengycins是枯草芽孢杆菌非核糖体合成的环状脂肽类抗生素,本文从其特性入手,研究了其抑制串珠镰刀菌的初步作用机制。普通显微观察结果显示,Fengycins处理能使部分串珠镰刀菌菌丝顶端破裂,进一步通过PI染色与荧光显微观察发现,Fengycins处理会导致串珠镰刀菌菌丝膜的损伤。在添加几丁质、壳聚糖、β-1,3葡聚糖、甾醇、胆固醇的平板内,Fengycins的抑菌活性没有受到太大影响;而在添加卵磷脂的平板,Fengycins的抑菌活性受到明显的拮抗。这些结果说明卵磷脂很可能是Fengycins在膜上的作用靶标。此外,研究还发现Fengycins能够抑制串珠镰刀菌分泌的磷脂酶A2的活性,该性质很可能也在Fengycins的抑菌活性中起到了一定作用。     

我国首例Paraconiothyrium cyclothyrioides感染致眼内炎的相关研究

目的报道我国首例由Paraconiothyrium cyclothyrioides引起的真菌性眼内炎,并分析其生物学特征、感染途径及治疗方法。方法通过形态学鉴定、生长温度试验、ITS测序等方法对我院1株眼外伤患者左眼前房沉积物中培养分离到的丝状真菌进行鉴定。结果该丝状真菌在PDA平板上在25℃生长快速,可见灰橄榄色周边有白色绒毛状菌落,表面皱褶,35℃生长缓慢,可见黄豆大小白色凸起菌落;25℃及35℃培养后镜下可见大量结节状菌丝,未见分生孢子,属于不产孢株;ITS测序结果为Paraconiothyrium cyclothyrioides。结论本病例是国内首次报导的由Paraconiothyrium cyclothyrioides引起的真菌性眼内炎。     

The occurrence of root rot and crown rot of rice in Gilan and Zanjan provinces, Iran

Root rot and crown rot of rice is one of the important fungal diseases of rice in Gilan and Zanjan provinces, Iran. During 1999--2002, samples of plant and soil around the roots of infected rice plants were collected and used to identify the causal agent. Root and crown parts were surface sterilized with sodium hypochlorite and then cultured on PDA (potato dextrose agar), PPA (pepton pentacholoritobenzene agar) and CLA (carnation leaf agar) media. Soil samples prepared in water agar were used to isolate the pathogen. The causal agent was identified as Fusarium moniliforme. Colonies were initially white but turned violet to grey late. Microconidia were arranged in chain and macroconidia were cylindrical and long with 3-5 septa. The disease was severe in Zanjan province particularly along Ghezel Ozan river where the infection ranged from 70-80%. Root and crown rot was more prevalent in areas where Champa and Gerdeh were being cultivated continuously. On the other hand, Sadri cultivars had relatively less infection. Persistent cultivation of rice and seed sowing method intensified disease development and caused significant economic losses.     

HIV感染患者口咽、鼻腔内真菌分离率的调查

目的了解HIV感染者口咽及鼻腔内真菌分离阳性率。方法用无菌拭子采集口咽腔溃疡、白斑、口角炎等和咽颊区黏膜分泌物,鼻腔取下鼻甲黏膜或中鼻道黏膜分泌物,直接接种于1 mL沙堡弱液体培养基中。取该离心沉淀物作真菌直接镜检,并接种于科玛嘉念珠菌显色培养基置37℃培养48 h后鉴定。如为丝状真菌,转种于察氏琼脂。25℃培养1周后根据菌落形态结合镜下结构鉴定菌种。结果 94例HIV感染者在口咽腔中真菌培养阳性62例(66%),分离出65株真菌,在鼻腔中真菌培养阳性48例(51%),分离出57株真菌。结论 HIV感染者免疫功能低下,易继发真菌机会性感染,口咽及鼻腔真菌的高寄居率是HIV侵袭性真菌感染的先兆症状,真菌菌种以白念珠菌比例为最高,口咽及鼻腔分别61%和33%。     

14例茄病镰刀菌所致角膜溃疡临床分析

目的探讨真菌性角膜溃疡的病原学特点、临床表现及抗真菌综合治疗的方法。方法对2004年10月-2006年10月送检的疑似感染的角膜标本进行镜检、培养及菌种鉴定。对其中14例病历资料完整的茄病镰刀菌所致角膜溃疡患者进行临床分析。结果在33例送检标本中分离出茄病镰刀菌24株（72．7％）。上述14例患者中,有3例角膜穿孔合并眼内炎行眼球内容物除去术,3例行结膜瓣或羊膜移植,1例角膜移植,7例经非手术治疗保留较好视力。结论茄病镰刀菌是我国北方真菌性角膜炎的主要致病菌,可导致视力严重受损且治愈困难。早期诊断配合以抗真菌为主的综合治疗可阻止病情进展,明显改善视力。     

Detection of mutagens produced by fungi with the Salmonella typhimurium assay.

Forty-one fungal isolates (one isolate per species) representing common plant pathogens and food crop contaminants were grown on sterile, polished rice and assayed for mutagenic activity in the Salmonella typhimurium-microsome system. Initially, single doses of aqueous and chloroform extracts of the moldy rice were assayed against the TA100 tester strain by incorporating extracts into the growth medium and by applying small quantities on disks placed on the agar surface. Suspected activity was examined further by analysis of several doses in the plate incorporation assay. Extracts of two aflatoxin-producing isolates (Aspergillus flavus and A. parasiticus) showed pronounced mutagenic activity, as did extracts of five other isolates (A. heterothallicus, A. nidulans, A. terricola, Alternaria tenuis, and Fusarium moniliforme) which did not contain detectable aflatoxins. Seven additional isolates (Botrytis cineria, Ceratocystis fimbriata, Cladosporium herbarum, Fusarium solani f. sp. pisi, Penicillium oxalicum, Thermomyces lanuginosus, and Verticilium albo-atrum) revealed activity which was possibly mutagenic; i.e., mutagenic responses were not observed in both the disk and incorporation assays, and clear dose-related activity was not observed in the incorporation assay. Extracts of the remaining fungi were not mutagenic in the bacterial assay.     

Detection of mutagens produced by fungi with the Salmonella typhimurium assay.

Forty-one fungal isolates (one isolate per species) representing common plant pathogens and food crop contaminants were grown on sterile, polished rice and assayed for mutagenic activity in the Salmonella typhimurium-microsome system. Initially, single doses of aqueous and chloroform extracts of the moldy rice were assayed against the TA100 tester strain by incorporating extracts into the growth medium and by applying small quantities on disks placed on the agar surface. Suspected activity was examined further by analysis of several doses in the plate incorporation assay. Extracts of two aflatoxin-producing isolates (Aspergillus flavus and A. parasiticus) showed pronounced mutagenic activity, as did extracts of five other isolates (A. heterothallicus, A. nidulans, A. terricola, Alternaria tenuis, and Fusarium moniliforme) which did not contain detectable aflatoxins. Seven additional isolates (Botrytis cineria, Ceratocystis fimbriata, Cladosporium herbarum, Fusarium solani f. sp. pisi, Penicillium oxalicum, Thermomyces lanuginosus, and Verticilium albo-atrum) revealed activity which was possibly mutagenic; i.e., mutagenic responses were not observed in both the disk and incorporation assays, and clear dose-related activity was not observed in the incorporation assay. Extracts of the remaining fungi were not mutagenic in the bacterial assay.     

Uptake of Glucose and Phosphorus by Growing Colonies of Fusarium oxysporum as Quantified by Image Analysis

Olsson, S. 1994. Uptake of glucose and phosphorus by growing colonies of Fusarium oxysporum as quantified by image analysis. Experimental Mycology 18, 33-47. The simplest of all heterogeneous environments for fungal colony growth is the petri dish with an agar medium. As the colony grows there will be a depression of nutrient concentrations under the colony caused by the uptake of nutrients by the growing colony. Image analysis methods have been developed for measuring medium concentrations of glucose and phosphorus with simultaneous biomass density determinations in agar systems. Maps of the concentrations in the agar medium under the colony and of colony biomass density were produced. A new method for weighing fungal colonies grown on agar is also presented. For Fusarium oxysporum phosphorus and glucose uptake from the medium was the same irrespective of the C/mineral ratios in the medium within the measured range of ratios. Even the concentration profiles of the nutrients under the colony were the same irrespective of nutrient ratios. Distribution of biomass density was affected by differences in glucose concentrations, being highest at the colony margin at the lower concentrations. The results indicate that the fungal colony is able to take up nutrients at the margin in excess of the local needs.     

Antagonistic Activity in Fusarium acuminatum

Ten of 19 (53%) tested isolates of Fusarium acuminatum , from different geographical origins and sources, showed in vitro antagonistic activity (inhibition at distance) to mycelial growth of F. moniliforme. Moreover, when F. acuminatum ITEM-728 was tested against 25 different fungal species, an initial inhibition at a distance was observed which was followed by the spread of the F. acuminatum mycelium over the opposite fungal colony to various degrees. Most of the F. acuminatum isolates which showed antagonistic activity proved to be enniatin B (EB) producers, and some of them also formed moniliformin (MF). The toxic activity of the methanol extract of F. acuminatum ITEM-728 towards some test microorganisms was closely related to the EB concentration. In particular, Bacillus subtilis proved to be a very sensitive test microorganism.