Genotyping of the MTL loci and susceptibility to two antifungal agents of Candida glabrata clinical isolates

The opportunistic fungal pathogen Candida glabrata is the second most common isolate from bloodstream infections worldwide and is naturally less susceptible to the antifungal drug fluconazole than other Candida species. C. glabrata is a haploid yeast that contains three mating-type like loci (MTL), although no sexual cycle has been described. Strains containing both types of mating information at the MTL1 locus are found in clinical isolates, but it is thought that strains containing type a information are more common. Here we investigated if a particular combination of mating type information at each MTLlocus is more prevalent in clinical isolates from hospitalized patients in Mexico and if there is a correlation between mating information and resistance to fluconazole and 5-fluorocytosine. We found that while both types of information at MTL1 are equally represented in a collection of 64 clinical isolates, the vast majority of isolates contain a-type information at MTL2 and α-type at MTL3. We also found no correlation of the particular combination of mating type information at the three MTL loci and resistance to fluconazole.

The inhibitive effect of adenovirus mediated CD gene and 5-FC on proliferative human retinal pigment epithelialcells / 中华眼底病杂志

Objective To study the inhibitive effect of adenovirus mediated CD gene and 5-FC on proliferative human retinal pigment epithelial (HRPE) cells, and to search for an effective method to take precautions against proliferative vitroretinopathy (PVR). Method Different concentrations of CD and 5-FC were added respectively to the cultured third-growth-generation HRPE cells.Transferance rate was detected by positive HRPE cells marked by X-gal and LacZ. The number of HRPE cells were counted and evaluated by methylthiazol-tetrazollium (MTT) method. Results The adenovirus mediated CD gene could be transfered into HRPE cells with a dose-dependent manner. Positive HRPE cells with CD gene could transform 5-FC to 5-Fu,which could inhibit the increase of HRPE cells effectively. No obvious bystander effect on the growth of HRPE cells was detected. Conclusions The adenovirus may introduce a foreign gene into cultured HRPE cells efficiently. It could be a good method to treat and prevent PVR by medication.

xperimental Study on Adenovirus-Mediated Suicide Gene Therapy for Human Hepatucellular Carcinoma Using Escherichia Coli Cytosine Deaminase / 中国肿瘤生物治疗杂志

To evaluate whether in vitro and in vivo transfer of E. Coli cytosine deaminase gene will confer sensitivity of a solid tumor to prodrug 5-fluorocytosine(5FC), we used an adenovirus vector(AdexCMV. CD) carrying the cytosine deaminase gene driven by the CMV promoter, infected SMMC-7721 or HepG2 cells hepatocellular carcinoma cells in vitro, and found AdexCMV. CD vector could effectively suppressed the growth of SMMC-7721 and HepG2 cells. When the two cells were infected with AdexAFP. CD vector in which the CD gene was driven by the AFP gene 5'-flanking region, only HepG2 cells were conferred sensitivity to 5FC. (Infection with AdexCMV.CD, when as few as 20% of cells transfected the CD gene, SMMC-7721 cells were associated with a bystander effect when combined with 5FC in cell mixing studies.) Consistent with these in vitro observations, AdexCMV. CD was directly injected into established subcutaneous SMMC-7721 tumors in nude mice receiving 5FC,there was a 60% reduction in tumor size at day 8, 70% reduction at day 24. Our results suggested that adenovirus-mediated tumor-specific gene transfer of CD gene and concomitant administration of 5 FC may have potential as a strategy for local control of tumor growth.

Induction of Tumor Cell Apoptosis by Adenovirus-Mediated E. coli Cyto-sine Deaminase Gene Transfection and Its Bystander eftect / 中国肿瘤生物治疗杂志

Adenoviruses harboring E. coli cytosine deaminase gene (AdCD) were used to transfect murine FBL-3 ery-throleukemia cells in vitro. FBL3 cells infected with AdCD were more sensitive to 5-fluorocytosine (5-FC) than cells infected with a control adenovirus AdLacZ. Further study indicated that this combination therapy (AdCD and 5-FC) killed tumor cells by inducing apoptosis of FBL-3 cells. The supematants from FBL-3 cells treated with AdCD/5-Fc were transferred on the culture system of uninfected (wild - type) FBL-3 cells, the result indicated that only 6.25% of the supernatant could induce significant cytotoxicity on wild type FBL3 cells. The results demonoustrated that bystander effect plays an important role in AdCD-mediated cytotoxicities. Direct injection of AdCD into established subcutaneous FBL3 tumor in mice followed by daily intraperitoneal injection of 5-FC for 10 days was found to inhibit tumor growth significant-

in vitro and in vivo Cytotoxic Effect of Adenovirus-Mediated Cytosine Deaminase Gene Transfer on Murine Melanoma / 中国肿瘤生物治疗杂志

Escherichia coli cytosine deaminase ( CD) gene was transfected into murine B16F10 melanoma cells by recombinant adenovirus AdCD in vitro . The tumor cells infected with AdCD were more sensitive to 5-fluorocytosine (5FC) than cells infected with a control adenovirus AdLacZ. The supernatant from B16F10 cells treated with AdCD/5FC was transferred to uninfected cells, and we found that only 6. 25 % of the supernatant could significantly inhibit the growth of wild type B16F10 cells. When AdCD was directly injected into established subcutaneous B16F10 tumors in mice followed by intraperitoneal injection of 5FC for 10 days, a significant reduction in tumor size and prolongation of survival period were observed. These studies not only explored the cytotoxic effects of AdCD/5FC on B16F10 melanoma cells in vitro and in vivo but also elucidated the mechanisms of its bvstander effect.

A Case of Cryptococcosis with Cutaneous Manifestation

We experienced a case of cryptococcosis in a 13-year-old female who had been admitted to our hospital because of intermittent high fever and generalized lymphadenopathy accompanied by multiple nodular eruptions with erosions on the face, scalp, neck and back. The patient was treated under the impression of tuberculous lymphadenitis without any improvement. A surgical biopsy of the lymph node and the subcutaneous nodule, which was performed 14 days later, revealed chronic granulomatous tissue and Langhan's type giant cells which contained numerous cryptococci. A brief review of the literature was done.