| Objective According to the traditional classification method, Geotrichum mainly concludes Geotrichum candidum, Geotrichum capitatum and Geotrichum clavatum.Among them ,Geotrichum candidum and Geotrichum capitatum are the most common. During the last decade, the reports of Geotrichum are less. we separated a new kind of Geotrichum from a patient of kerionforme geotrichosis in 2002, which identified as Geotrichum silvicola by China Institute of Microbiology in Academy Science.It had not been writtened in the newest edition of national fungus species catalogue in 1997, and had not be published formally yet .It was separated from Brazil drosophila by others.Now we separated it from human firstly at home and abroad.There was no reports about Geotrichum silvicola's morphology, biochemistry and pathogenicity by far. Only the aspect of its gene has began the first step.Our test do the primary research about morphology ,biochemistry ,DNA sequecing and so on. Hair infect test and Animal test showed the fungus' pathogenicity furtherly.Above all, our study leads a new way for the diagnosis and treatment of Geotrichum silvicola infection. Methods1 Fungi culture inoculating the fungus in the improved Sabouraud's agar culture, then putting them under 27℃and 37℃ respectively. Three days later,observing the colony. Direct microscope examination:Picking a little colony on the glass slice , add 10% KOH and coverring it by glass slice, Observing the colony appearance carefully under low-time and high-time microscope. Electron microscope : stabling the fungus cultured 3-10 days. Observing it by electron microscope .2 Hair infect test inoculating the strain on improved Sabouraud's agar solide and fluid culture respectively, sterilizing the hair with high pressure and put it on culture . Observating it once a week to study the condition of the hair invaded by microscope .3 Animal test choosing sixty guinea pigs.Selecting thirty guinea pigs randomly to be injected 800mg/kg cyclophosphamide and 0.5mg decadron once a guinea pig,another thirty guinea pigs as the contrast group which be done nothing. Three days later, using wiping skin method and the subcutaneous injection method to inoculate the fungal suspend solution on one side back of guinea pigs ( concentration is 2 × 106 CFU), another side to be inoculated 0.9% Nacl.Ten days later ,observing the result.4 Biochemestry test inoculating the fungus in the improved Sabouraud's agar culture, then putting them under 37℃.After three days ,making up fungal suspension solution ,using the Test Kit of API20C AUX, analoging it by Microscan WalkAway-40 automatic microbe analysis instrument.5 DNA sequence analysis analysizing and testing the strain's 26SDNAD1/D2 region .Using the GenBank/ EMBL/ DDBJ/ PDB nucleotide sequence databases to index the homogeneity sequencing.6 Tempreture test inoculating it and put it under 27℃,37℃ and 42℃ respectively. A week later,changing the clonies under 27℃ and 37℃ each other.observing the result three days later. 7 Drug susceptibility testing in vitro the drug susceptibility testing kit supplied by Tienjin Jinzhang Institude . Inoculating the fungus in the improved Sabour's culture, then putting them under 37℃. Three days later,making up fungal suspend solution . Using the Mesh 0.5 tube to regulate the fungal suspend solution to the exact level.Inoculating and hatching it under 35 ℃. observating the result 24h and 48h later respectively.Results 1 Fungi culture: the appearances of colony at 27℃ are milky moist creamy and smooth,but wrinkled in the middle after three days.Ten days later, the colonies are adhered,and their color is milk yellow.The fuzzy grow up on he surface.The creamy colonies are always moist and show the color of milky or milk yellow at 37℃. Nothing grows under 41℃.Direct microscope examination: there were a lot of rectangular arthrospores,round or oval spores with or without buddings,as well as branched filaments.Through scanning electron microscope,we c...
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