Cryptococcus neoformans is an important conditional pathogenic fungus;the capsular polysaccharide surrounding its outer wall is the first identified major toxic factor of Cryptococcus neoformans.This review summarizes the progress in the research of capsule characteristics and dynamics of Cryptococcus neoformans,including the structural changes,tissue constitution,development and growth,etc,hoping to provide a basis and new ideas for studying Cryptococcus neoformans related diseases.

Objective To investigate the DNA typing, observe relationship between DNA fingerprinting patterns and serotypes of Cryptococcus neoformans, and find a suitable genotyping standard for Cryptococcus neoformans. Methods Three primers, including CN 1(GTG) 5, CN 2(GACA) 4 and CN 3(GATA) 4, were used to distinguish variations among strains of C.neoformans. Results The distinguishable fingerprinting bands for serotype of C.neoformans were yielded by primer CN 2. Using this primer, of 24 clinical and environmental isolates of serotype A of C.neoformans and 8 standard strains investigated by PCR, 20 strains produced complete identical fingerprinting patterns, the other 4 strains had different fingerprinting patterns. 2 strains of serotype B and C yielded indistinguishable fingerprinting patterns. Conclusions ①The majority of strains of serotype A had similar and stable fingerprinting patterns. ②Some strains of serotype B and C had an indistinguishable fingerprinting patterns. ③The same serotype strains from different sources may produce different DNA fingerprinting patterns. ④The DNA fingerprinting is a rapid, simple and feasible method for identifying Cryptococcus neoformans.

Objective To evaluate the viability of Cryptococcus in cerebrospinal fluid of patients with cryptococcal meningitis.Methods Electron microscopy,animal inocul ation and neutral red staining of the cere-brospinal fluid specimens were empl oyed.Results Transmission electron microscopy r evealed intact cells and budding cells of cryptococcus which appeared frequently during the early treatment.Edema of cytoplasm and d isar-rangement of structure of capsule we re often found during the later thera py.All mice inoculated experimenta lly with the cerebrospinal fluid specimens were positive on direct examination b ut negative in routine culture were i nfected.A definite number of deep blood-red fu ngal cells were observed in many spec imens.Conclusion These findings add a new approach for dynamic studying o f the viability of Cryptococcus in cerebrospinal fluid of patients with Crypto-coccal meningitis and provide an imp ortant parameter for evaluating therapeutic effect.

This paper reports 20 patients with cryptococcal meningitis,which were misdiagnosed before anti-fungal therapy,and the majority of them was diagnosed as tuberculous meningitis or viral meningitis.These patients were treated either with amphotericin B or fluconazale alone,or in combina- tion with flucytosine respectively,of the 15 patients could be evaluated,10 were cured(66.7%),2 im- proved(13.3%),3 died(20%),1 relapsed(10%).The mortality rate among the under age group and the aged group was significantly higher than that of the adult group(71.4% vs 23%).It is the authors' experience that in the early stage intrathecal amphotericin B combines with intravenous fluoconazole and changes to oral fluconazole or itraconazole in the later stage may be a valuable approach for cryptococcal meningitis.

Polymerase chain reaction(PCR) was used for the first time in China for the diagnosis of cryptococcal meningitis by amplification of specific sequence of the rDNA genes of C.neoformans.All 11 strains of C.neoformans yielded a specific 136 bp fragment but 21 non-C,neoformans strains did not. The sensitivity of the amplification was about 10 cfu.With the aid of the rDNA-PCR,23 of the 23 cere- brospinal fluids (CSF) specimens which had been confirmed C.neoforrnans positive by smear and/or cul- ture were PCR-positive(100%),and 13 of the 14 CSF specimens which had been confirmed C.neofor- mans negative by smear and culture were PCR-negative (93%).The results of the present study suggest that rDNA-PCR is a sensitive and specific method for rapid diagnosis of cryptococcal meningitis.

To screen specific DNA probes by double hybridization from the constructed DNA li- brary of serotype A Cryptococcus neoformans.On the basis of the nucleotide sequence of vector pUC18, a pair of primers was synthesized.The insert fragments were amplified from the library on a PCR pro- cessor.The PCR products were spotted onto hybond-N~+ membranes.All inserts amplified from the ge- nomic library by PCR were screened by dot blot with 26 ~(32)P-labelled DNA from infectious agents for dif- ferentiation and from healthy persons.Twenty-eight candidate clones were obtained.The twenty-eight clone inserts got from low melting point agar were further characterized by dot blot with above 27 kinds of DNA for differentiation.Three specific DNA probes from the library of serotype A Cryptococcus neo- formans were obtained.Colony pCNIIA6 was serotype A-specific,which gave signals only with sertype A strain and did not cross hybridize with other DNAs.Colony pCNIIB5 was species-specific which gave signals only with DNA from Cryptococcus neoformans.Colony pCNIIIG1 was specific for var.neofor- mans,which gave signals only with serotype A and D strains.We can make a rapid diagnosis of Crypto- coccus neoformans infection at an early stage and distinguish the variants of C.neoformans and C.gattii using above specific probes.

Objective To explore the mechanism of Cryptococcus neoformans mutant in CNLAC1and investigate the difference of CNLAC1between wild type(Mel+ )and the mutant (Mel- ).Methods The ab-normal PCR DNA product of Cryptococcus neoformans was cloned into sequencing vector PG EM-T for se-quencing.An expression vector was c onstructed for efficient expressio n in E.coli DH 5? .The gene was sequenced.Results The cloned DNA sequence was found to b e different between wild type(Mel+)and the mutant (Mel-)(between 1715bp and 2617bp).The differences were not only in len gth,but also in base sequence.Con-clusion The mechanism of the mutant in CNLAC1might be a change of sequence(between 1715bp and 2617bp),and not a DNA deletion.This finding might provide us a target gene for the prognosis and treatment of cryptococcosis.

Objective:To observe the efficacy and safety of itraconazole in treatment of onychomycosis and its influence on nail growth speed. Methods: In a multicentre open study involving 15 medical units nationwide, patients with onychomycosis were treated with orally itraconazole pulse therapy. At each stage after treatment, the clinical efficacy,mycological efficacy, and side-effects of the therapy and the net growth length of normal nail deck were observed.Results: The therapy had a satisfactory efficacy and prolonged effect in treating onychomycosis for both affected fingers and toe nails. The therapy was effective for onychomycosis infected with dermatophyton, yeast or non-dermatophyton fungus and had a fungus-eliminating-rate of 97.86%. The average net growth length of normal nail deck in affected toe nails was slightly longer than that in finger nails on 6 months and 9 months after treatment.No severe side effects were found. Conclusion: Itraconazole pulse therapy is effective and safe for onychomychosis and can increase nail growth length,especially for toe nails.

Objective:To study the relationship between susceptibilities of Trichophyton rubrum strains to antifungal agents and their species specificities.Methods: The susceptibilities of Trichophyton rubrum strains to itraconazole,ketoconazole,fluconazole,terbinafine,naftifine,5-flucytosine and amphotericin B were evaluated using a modified microdilution method.The relationship between susceptibilities and genotypes and phenotypes of Trichophyton rubrum strains with different origins was analyzed by random amplified polymorphic DNA(RAPD).Results: The Trichophyton rubrum strains showed narrow minimum inhibitory concentration(MIC) ranges to terbinafine(0.016-0.032 ?g/ml),naftifine(0.032-0.063 ?g/ml) and itraconazole(0.25-1 ?g/ml),whereas they showed broader MIC ranges to ketoconzole(0.25-2 ?g/ml)and fluconazole(1-32 ?g/ml).MICs of Trichophyton rubrum strains to terbinafine(M_0=0.032 ?g/ml) and naftifine(M_0=0.032 ?g/ml) were the lowest among 7 antifungal agents.Wilcoxon test(Kruskal-Wallis test) suggested that there was no significant relationship of MICs to terbinafine,naftifine,itraconazole and amphotericin B with the genotypes,phenotypes and origins of the Trichophyton rubrum strains.Conclusion: The antifungal susceptibility of Trichophyton rubrum strains may not be related to their genotypes,phenotypes or from which part of the body they are isolated.

Objective To study the effect of capsule deficient strains CAP64 on apoptosis of mice microglia cell line (N9) cell in vitro . Methods N9 cells were co cultured with CAP64, the flow cytometry was employed to detect the N9 cellular apoptosis on different phase. Results The average apoptotic index of N9 after cultured for 2、4、8、16、24 hours with CAP64 were 9 33%、12 93%、15 37%、16 30% and 20 5%, respectively. There were significant differences between experimental group and control group. Conclusion Capsule deficient strains CAP64 can induce microglia cell line (N9) apoptosis