Evaluación de susceptibilidad en cándidas spp por colorimetría obtenida en gestantes de un hospital obstétrico / Susceptibility evaluation in candida spp by colorimetry obtained in pregnant women from an obstetric hospital / Avaliação da suscetibilidade em cândida spp por colorimetria obtida em gestantes de um hospital obstétrico

INTRODUCCIÓN: las infecciones fúngicas ocasionadas por levaduras del género Cándida son extremadamente comunes en mujeres de edad reproductiva, y constituyen un motivo de atención medica de salud. OBJETIVO: evaluar la susceptibilidad de Cándidas spp, mediante el método colorimétrico (Integral Yeast System Plus). MÉTODO: fue de tipo descriptivo, transversal; se recopiló información mediante observación directa en campo y el análisis documental para obtener información bibliográfica de tipo secundaria. RESULTADOS: de los 72 casos encontrados de Cándida Albicans revela que son susceptibles a la anfotericina B (2ug/ml); de los 5 casos encontrados de Cándida Krusei revela que son sensibles a la Anfotericina B (2ug/ml); De 1 caso encontrado de Cándida Parapsilosis revela sensibilidad en la Nistatina (1.25ug/ml). En este estudio la prevalencia de la infección por Cándida fue del (44.98%). CONCLUSIONES: Cándida Albicans fue la especie más común aislada en las mujeres embarazadas representando un 72%, En la evaluación de la susceptibilidad a través del kit Integral System Yeast Plus se obtuvo que Cándida Albicans es susceptible a Anfotericina B, Flucitosina entre otros, en Cándida Glabrata se obtuvo que es sensible a la Nistatina, Anfotericina B, susceptible entre otros, en Cándida Krusei se obtuvo que es sensible a la Anfotericina B, Clotrimazol, Miconazol, susceptibles a la Nistatina, Voriconazol y resistente a la Flucitosina, Ketoconazol, Itraconazol y Fluconazol.

INTRODUCTION: fungal infections caused by yeast of the genus Candida are extremely common in women of reproductive age, and constitute a reason for medical health care. OBJECTIVE: to evaluate the susceptibility of Candida spp, using the colorimetric method (Integral Yeast System Plus). METHOD: it was descriptive, transversal; Information was collected through direct observation in the field and documentary analysis to obtain secondary bibliographic information. RESULTS: of the 72 cases found, Candida Albicans reveals that they are susceptible to amphotericin B (2ug / ml); of the 5 cases found, Candida Krusei reveals that they are sensitive to Amphotericin B (2ug / ml); Of 1 case found of Candida Parapsilosis reveals sensitivity in Nystatin (1.25ug / ml). In this study, the prevalence of Candida infection was (44.98%). CONCLUSIONS: Candida Albicans was the most common species isolated in pregnant women, representing 72%. In the evaluation of susceptibility through the Integral System Yeast Plus kit it was obtained that Candida Albicans is susceptible to Amphotericin B, Flucytosine among others, in Candida Glabrata was obtained that it is sensitive to Nystatin, Amphotericin B, susceptible among others, in Candida Krusei it was obtained that it is sensitive to Amphotericin B, Clotrimazole, Miconazole, susceptible to Nystatin, Voriconazole and resistant to Flucytosin, Ketoconazole, Itraconazole and Fluconazole.

INTRODUÇÃO: as infecções fúngicas causadas por leveduras do gênero Candida são extremamente comuns em mulheres em idade reprodutiva e constituem motivo de cuidados médicos. OBJETIVO: avaliar a suscetibilidade de Candida spp, por meio do método colorimétrico (Integral Yeast System Plus). MÉTODO: foi descritivo, transversal; as informações foram coletadas por meio de observação direta em campo e análise documental para obtenção de informações bibliográficas secundárias. RESULTADOS: Dos 72 casos encontrados, Cândida Albicans revelou ser suscetíveis à anfotericina B (2ug /ml); dos 5 casos encontrados, Candida Krusei revela que são sensíveis à Anfotericina B (2ug / ml); de 1 caso encontrado de Candida Parapsilosis revela sensibilidade na Nistatina (1,25ug / ml). Neste estudo, a prevalência de infecção por Candida foi (44,98%). CONCLUSÕES: Cândida Albicans foi a espécie mais comum isolada em gestantes, representando 72%. Na avaliação da susceptibilidade através do kit Integral System Yeast Plus foi obtido que Candida Albicans é suscetível à Anfotericina B, Flucitosina entre outras, em Cândida Glabrata foi obtido que é sensível a Nistatina, Anfotericina B, suscetível entre outras, em Candida Krusei foi obtido que é sensível a Anfotericina B, Clotrimazol, Miconazol, suscetível a Nistatina, Voriconazol e resistente a Flucitosina, Cetoconazol, Itraconazol e Fluconazol.

A Potential Therapy Using Engineered Stem Cells Prevented Malignant Melanoma in Cellular and Xenograft Mouse Models / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: In the present study, human neural stem cells (hNSCs) with tumor-tropic behavior were used as drug delivery vehicle to selectively target melanoma. A hNSC line (HB1.F3) was transduced into two types: one expressed only the cytosine deaminase (CD) gene (HB1.F3. CD) and the other expressed both CD and human interferon-β (IFN-β) genes (HB1.F3.CD. IFN-β). MATERIALS AND METHODS: This study verified the tumor-tropic migratory competence of engineered hNSCs on melanoma (A375SM) using a modified Boyden chamber assay in vitro and CM-DiI staining in vivo. The antitumor effect of HB1.F3.CD and HB1.F3.CD.IFN-β on melanoma was also confirmed using an MTT assay in vitro and xenograft mouse models. RESULTS: A secreted form of IFN-β from the HB1.F3.CD.IFN-β cells modified the epithelial-mesenchymal transition (EMT) process and metastasis of melanoma. 5-Fluorouracil treatment also accelerated the expression of the pro-apoptotic protein BAX and decelerated the expression of the anti-apoptotic protein Bcl-xL on melanoma cell line. CONCLUSION: Our results illustrate that engineered hNSCs prevented malignant melanoma cells from proliferating in the presence of the prodrug, and the form that secreted IFN-β intervened in the EMT process and melanoma metastasis. Hence, neural stem cell-directed enzyme/prodrug therapy is a plausible treatment for malignant melanoma.

Effects of neural stem cells and 5-fluorocytosine in canine metastatic lung tumor

This is the first case report to describe the tumor regressive effect of systemic human neural stem cell (NSC)/5-fluorocytosine (5-FC) therapy on canine metastatic lung tumor. The therapeutic effects appeared approximately two weeks after 5-FC administration. Thoracic radiographs revealed a reduced number of lung nodules and decreased nodule size. However, there were no significant antitumor effects on primary lesions in abdominal organs. In conclusion, human NSC/5-FC prodrug therapy can secure patient quality of life with the same or more therapeutic effects and fewer side effects than other recommended chemotherapies.

Anti-proliferative Effect of Engineered Neural Stem Cells Expressing Cytosine Deaminase and Interferon-β against Lymph Node–Derived Metastatic Colorectal Adenocarcinoma in Cellular and Xenograft Mouse Models / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Genetically engineered stem cells may be advantageous for gene therapy against various human cancers due to their inherent tumor-tropic properties. In this study, genetically engineered human neural stem cells (HB1.F3) expressing Escherichia coli cytosine deaminase (CD) (HB1.F3.CD) and human interferon-β (IFN-β) (HB1.F3.CD.IFN-β) were employed against lymph node–derived metastatic colorectal adenocarcinoma. MATERIALS AND METHODS: CD can convert a prodrug, 5-fluorocytosine (5-FC), to active 5-fluorouracil, which inhibits tumor growth through the inhibition of DNA synthesis,while IFN-β also strongly inhibits tumor growth by inducing the apoptotic process. In reverse transcription polymerase chain reaction analysis, we confirmed that HB1.F3.CD cells expressed the CD gene and HB1.F3.CD.IFN-β cells expressed both CD and IFN-β genes. RESULTS: In results of a modified trans-well migration assay, HB1.F3.CD and HB1.F3.CD.IFN-β cells selectively migrated toward SW-620, human lymph node–derived metastatic colorectal adenocarcinoma cells. The viability of SW-620 cells was significantly reduced when co-cultured with HB1.F3.CD or HB1.F3.CD.IFN-β cells in the presence of 5-FC. In addition, it was found that the tumor-tropic properties of these engineered human neural stem cells (hNSCs) were attributed to chemoattractant molecules including stromal cell-derived factor 1, c-Kit, urokinase receptor, urokinase-type plasminogen activator, and C-C chemokine receptor type 2 secreted by SW-620 cells. In a xenograft mouse model, treatment with hNSC resulted in significantly inhibited growth of the tumor mass without virulent effects on the animals. CONCLUSION: The current results indicate that engineered hNSCs and a prodrug treatment inhibited the growth of SW-620 cells. Therefore, hNSC therapy may be a clinically effective tool for the treatment of lymph node metastatic colorectal cancer.

A Case of Fungal Keratitis Caused by Purpureocillium lilacinum: A Microbiological Review of Korean Cases / 대한의진균학회지

Purpureocillium(P) lilacinum is a ubiquitous, saprophytic filamentous fungus that is infrequently reported in keratitis and cutaneous infections. However, the microbiological characterization of the culture isolates is limited in Korea. A 56-year-old male who suffered a pine needlestick to his right eye 10 days previously presented with ocular opacity and pain. A microscopic examination of a corneal scraping by Gram staining and calcofluor white staining was negative for bacteria and fungi. Fungal culture yielded pure white cottony molds on Sabouraud's dextrose agar after a 3-day incubation. Microscopic examination further revealed a mixture of a verticillate arrangement of phialides resembling the Penicillium structure and sparsely branched conidiophores bearing single to small clusters of conidia. This was initially presumed to be a species of Penicillium but the colonies never turned green with further incubation. It was subsequently identified as P. lilacinum by 28S rDNA sequencing and MALDI-TOF mass spectrometry. Antifungal susceptibility test revealed that this organism was resistant to flucytosine, amphotericin B, fluconazole, itraconazole, voriconazole, and caspofungin. After treatment with topical 5% voriconazole and oral itrazonazole combined with multiple debridements for 2 weeks, the patient was discharged with improved visual acuity. We thus report the first case of P. lilacinum infection that required molecular identification due to mixed conidiogenesis features and that showed laboratory-confirmed antifungal resistance in Korea.

Human Sulfatase-1 Improves the Effectiveness of Cytosine Deaminase Suicide Gene Therapy with 5-Fluorocytosine Treatment on Hepatocellular Carcinoma Cell Line HepG2 In Vitro and In Vivo / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human sulfatase-1 (Hsulf-1) is an endosulfatase that selectively removes sulfate groups from heparan sulfate proteoglycans (HSPGs), altering the binding of several growth factors and cytokines to HSPG to regulate cell proliferation, cell motility, and apoptosis. We investigated the role of combined cancer gene therapy with Hsulf-1 and cytosine deaminase/5-fluorocytosine (CD/5-FC) suicide gene on a hepatocellular carcinoma (HCC) cell line, HepG2, in vitro and in vivo.</p><p><b>METHODS</b>Reverse transcription polymerase chain reaction and immunohistochemistry were used to determine the expression of Hsulf-1 in HCC. Cell apoptosis was observed through flow cytometry instrument and mechanism of Hsulf-1 to enhance the cytotoxicity of 5-FC against HCC was analyzed in HCC by confocal microscopy. We also establish a nude mice model of HCC to address the effect of Hsulf-1 expression on the CD/5-FC suicide gene therapy in vivo.</p><p><b>RESULTS</b>A significant decrease in HepG2 cell proliferation and an increase in HepG2 cell apoptosis were observed when Hsulf-1 expression was combined with the CD/5-FC gene suicide system. A noticeable bystander effect was observed when the Hsulf-1 and CD genes were co-expressed. Intracellular calcium was also increased after HepG2 cells were infected with the Hsulf-1 gene. In vivo studies showed that the suppression of tumor growth was more pronounced in animals treated with the Hsulf-1 plus CD than those treated with either gene therapy alone, and the combined treatment resulted in a significant increase in survival.</p><p><b>CONCLUSIONS</b>Hsulf-1 expression combined with the CD/5-FC gene suicide system could be an effective treatment approach for HCC.</p>

Selective Delivery of a Therapeutic Gene for Treatment of Head and Neck Squamous Cell Carcinoma Using Human Neural Stem Cells

OBJECTIVES: Based on studies of the extensive tropism of neural stem cells (NSCs) toward malignant brain tumor, we hypothesized that NSCs could also target head and neck squamous cell carcinoma (HNSCC) and could be used as a cellular therapeutic delivery system. METHODS: To apply this strategy to the treatment of HNSCC, we used a human NSC line expressing cytosine deaminase (HB1.F3-CD), an enzyme that converts 5-fluorocytosine (5-FC) into 5-fluorouracil (5-FU), an anticancer agent. HB1. F3-CD in combination with 5-FC were cocultured with the HNSCC (SNU-1041) to examine the cytotoxicity on target tumor cells in vitro. For in vivo studies, an HNSCC mouse model was created by subcutaneous implantation of human HNSCC cells into athymic nude mice. HB1.F3-CD cells were injected into mice using tumoral, peritumoral, or intravenous injections, followed by systemic 5-FC administration. RESULTS: In vitro, the HB1.F3-CD cells significantly inhibited the growth of an HNSCC cell line in the presence of the 5-FC. Independent of the method of injection, the HB1.F3-CD cells migrated to the HNSCC tumor, causing a significant reduction in tumor volume. In comparison to 5-FU administration, HB1.F3-CD cell injection followed by 5-FC administration reduced systemic toxicity, but achieved the same level of therapeutic efficacy. CONCLUSION: Transplantation of human NSCs that express the suicide enzyme cytosine deaminase combined with systemic administration of the prodrug 5-FC may be an effective regimen for the treatment of HNSCC.

Antitumor activity of the recombinant rClone30-CD/5-FC system / 药学学报

5-Flucytosine (5-FC) could be changed to 5-fluorouracil (5-FU) by cytosine deaminase (CD), the latter is able to kill cancer cells. However, there is no efficient method to deliver the CD gene into the tumor cells, which hampers the application of the suicide gene system. In this experiment, for the first time, the NDV has been utilized as a vector to deliver the CD gene into the cancer cells, the virus can infect the cancer cells specifically, replicate and assemble, while the cytosine deaminase is expressed. Then the CD converts the prodrug 5-FC into 5-FU to achieve the purpose of inhibiting tumor. Firstly, the whole genome of E. coli JM109 was extracted, and the CD gene was obtained by cloning method. Then the CD and IRES-EGFP were ligated into the pEE12.4 expression vector to become a recombinant pEE12.4IE-CD eukaryotic expression plasmid. The human liver cancer cells were transfected with the plasmid. The cells were treated with different concentrations of 5-FC, MTT method was used to determine the killing effect of CD/5-FC system on the human liver cancer cells. The cell deaths were 18.07%, 42.98% and 62.20% respectively when the concentrations of prodrug were at 10, 20 and 30 mmol x L(-1). In 5-FC acute toxicity experiment, Kunming mice were injected with different concentrations of 5-FC at intervals of 1:0.5. The LD50 of 5-FC through iv injection was determined by improved Karber's method, the LD50 was 507 mg x kg(-1) and the 95% confidence limit was 374-695 mg x kg(-1). According to the maximum LD0 dose of the LD50, the maximum safe dose was 200 mg x kg(-1). Body weight and clinic symptoms of the experimental animals were observed. These results laid the foundation to verify the antitumor effect and safety of CD/5-FC system in animal models. The CD gene was ligated into the NDV (rClone30) carrier, then the tumor-bearing animal was established to perform the tumor inhibiting experiment. The result showed that the recombinant rClone30-CD/5-FC system has a high antitumor activity in vivo. To summarize, CD gene has been cloned and its bioactivity has been confirmed in the mammalian cells. It is the first time in this study to utilize the recombinant NDV to deliver the CD gene into the tumor cells; our result proves the rClone30-CD/5-FC system is a potential method for cancer therapy.

Treatment of cryptococcal meningitis with low-dose amphotericin B and flucytosine / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Amphotericin B (0.7 mg/kg) with flucytosine is the standard treatment for cryptococcal meningitis. However, the long treatment course can induce adverse reactions in patients; therefore, reducing the dose may decrease such reactions. We performed a retrospective analysis of treatment effects and adverse reactions when amphotericin B (0.4 mg/kg or 0.7 mg/kg per day) and flucytosine were used together to treat HIV-negative patients with cryptococcal meningitis.</p><p><b>METHODS</b>Retrospective analysis was conducted on inpatients at the First Affiliated Hospital, College of Medicine, Zhejiang University (January 2005 to December 2009). Low- or high-dose amphotericin B (0.4 or 0.7 mg/kg per day, respectively) plus flucytosine was used. The negative conversion rate of Cryptococcus in the cerebrospinal fluid (CSF), patient mortality, and the incidence of side effects for the two groups (low- vs. high-dose) were compared immediately after treatment and 2 and 10 weeks later. Data were analyzed by the Student's t test, chi-square tests using SPSS 12.0 statistical software.</p><p><b>RESULTS</b>Two weeks post-treatment, Cryptococcus negative CSF rates were 78% (18/23) in the low-dose group and 87% (13/15) in the high-dose group (P = 0.28). Ten weeks post-treatment, both groups were negative. The mortality rate was 8% (2/25) in the low-dose group and 17% (3/18) in the high-dose group (P = 0.25). There was a statistically significant difference in the incidence of adverse events between the groups, 48% (12/25) and 78% (14/18) in the low- and high-dose groups, respectively (P = 0.04). Adverse events that required a change in treatment program in the low-dose group were 12% (3/25) compared to 39% (7/18) in the high-dose group (P = 0.04).</p><p><b>CONCLUSION</b>Low-dose treatment regimens were better tolerated than high-dose ones.</p>

The First Korean Case of Candidemia due to Candida dubliniensis

Candidemia due to uncommon Candida spp. appears to be increasing in incidence. C. dubliniensis has been increasingly recovered from individuals not infected with HIV. Identification of C. dubliniensis can be problematic in routine clinical practice due to its phenotypic resemblance to C. albicans. We report the first case of C. dubliniensis candidemia in Korea, which occurred in a 64-yr-old woman who presented with partial seizure, drowsiness, and recurrent fever. Germ-tube positive yeast that was isolated from blood and central venous catheter tip cultures formed smooth, white colonies on sheep blood agar and Sabouraud agar plates, indicative of Candida spp. C. dubliniensis was identified using the Vitek 2 system (bioMerieux, USA), latex agglutination, chromogenic agar, and multiplex PCR. The blood isolate was susceptible to flucytosine, fluconazole, voriconazole, and amphotericin B. After removal of the central venous catheter and initiation of fluconazole treatment, the patient's condition gradually improved, and she was cleared for discharge from our hospital. Both clinicians and microbiologists should be aware of predisposing factors to C. dubliniensis candidemia in order to promote early diagnosis and appropriate treatment.

Evaluación de tres métodos para la detección de la sensibilidad in vitro de especies de Candida a los antifúngicos / Evaluation of three methods for in vitro detection of antifungal susceptibility of Candida species

Los métodos de referencia E. Def 7.1 y M27-A3, que detectan resistencia in vitro a los antifúngicos, son onerosos y muy laboriosos, por lo que su implementación en los laboratorios hospitalarios es limitada. Existen técnicas comerciales de simple realización, que permitirían obtener resultados comparables a los que se obtienen con los métodos estándares. Los objetivos de esta investigación fueron: a) comparar los resultados de concentración inhibitoria mínima obtenidos según el método de referencia E.Def 7.1 con los obtenidos mediante el empleo del equipo comercial ATB® Fungus 3 en un conjunto de 82 aislamientos clínicos de Candida spp. frente a los siguientes antifúngicos: anfotericina B, 5-fluorocitosina, fluconazol e itraconazol; b) comparar en ese mismo conjunto de aislamientos los resultados del estudio de sensibilidad al fluconazol por difusión en agar empleando tabletas Neo-SensitabsTM o discos Malbrán con los que se obtienen por el método de referencia. La concordancia general entre el método de referencia y el ATB® Fungus 3 fue del 90,2 %, mientras que la concordancia del método de referencia con los métodos por difusión con discos y con tabletas alcanzó el 96,3% y el 92,7 %, respectivamente. El ATB® Fungus 3 fue eficaz para determinar la sensibilidad a la anfotericina B y a la 5-fluorocitosina, pero se observaron discrepancias al evaluar la sensibilidad a los azoles. Los métodos por difusión resultaron útiles para determinar la sensibilidad al fluconazol; sin embargo, observamos 3 discrepancias muy mayores, 1 mayor y 2 menores con el método de difusión con tabletas, mientras que con los discos solo se produjeron 3 discrepancias menores.

Reference methods E.Def 7.1 and M27-A3 detect in vitro resistance; however, they are expensive and very laborious. Thus, their actual use in hospital laboratories is limited. There are commercial techniques available, having easier accessibility and development, which would yield results comparable to those of the reference methods. The objectives of this study were: a) to compare the results of minimal inhibitory concentration of 82 Candida spp. clinic isolates according to reference method E.Def 7.1 and ATB® Fungus 3; b) to compare the results of fluconazole susceptibility testing by disk diffusion in agar with Neo-SensitabsTM tablets and Malbrán disks with those of the reference methods. Minimal inhibitory concentration for amphotericin B, 5-flucytosine, fluconazole and itraconazole was performed according to the E.Def 7.1 and the ATB Fungus 3 methods and diffusion was carried out with fluconazole disks and tablets. General concordance between the reference method and ATB Fungus 3 was 90.2 % and 96.3 and 92.7% for diffusion with disks and tablets. The ATB Fungus 3 method was effective to determine susceptibility against amphotericin B and 5-flucytosine; however, discrepancies were observed with azole drugs. Disk diffusion methods are useful to determine susceptibility to fluconazole; however, 3 very major, 1 major and 2 minor errors were observed with the tablets, whereas only 3 minor errors were observed with the disks.

Meningite criptocócica na gravidez: revisão de aspectos terapêuticos / Cryptococcal meningitis in pregnancy: review of the therapeutic aspects

A criptococose é uma infecção fúngica, cujo envolvimento do sistema nervoso central é caracteristicamente insidioso, apresentando sinais de irritação meníngea, sequelas neurológicas e alta mortalidade. A gestação, condição que leva a certo grau de imunossupressão, pode dificultar a resposta ao tratamento. Objetivando determinar a estratégia de tratamento mais efetiva para meningite criptocócica em grávidas sem outras condições de imunossupressão, o presente trabalho realizou um levantamento bibliográfico acerca do tema. Foram revisados cinco artigos, os quais evidenciaram ampla utilização de anfotericina B em monoterapia ou associada à flucitosina, inclusive no primeiro, segundo e terceiro trimestre de gestação. Também foi relatada a utilização de fluconazol e itraconazol. Em todos os relatos, os resultados foram favoráveis tanto para mãe quanto para a criança. Existem poucos dados disponíveis na literatura acerca do tema proposto. Preferencialmente, a conduta a ser realizada envolve internação da gestante como gravidez de alto risco e administração de anfotericina B. Embora os resultados apresentados tenham sido favoráveis tanto para a monoterapia com anfotericina B quanto para sua associação com flucitosina, ou para monoterapia com fluconazol ou itraconazol, são necessários estudos prospectivos, controlados e randomizados para determinar o esquema terapêutico significativamente mais eficaz para o tratamento da criptococose em gestantes

Cryptococcosis is an infection caused by a fungus, whose involvement in the central nervous system is characteristically insidious, presenting signs of meningitis, neurological sequelae, and high mortality. The pregnancy, a condition that leads to a certain degree of immunosupression, may hinder the response to treatment. With the aim of determining the most effective treatment for cryptococcal meningitis in pregnant women without other causes of immunodeficiency, this paper carried out a survey about the subject. Five articles were analyzed and they showed a wide utilization of amphotericin B as monotherapy or associated with flucytosine in the treatment of cryptococcal meningitis in pregnant women, which includes the usage during the first, second and third trimesters of pregnancy. It was also reported the usage of itraconazole and fluconazol. The results were positive in all articles for both mother and fetus. There are few data available in the literature about this theme. Preferably, the physician should proceed with the admission of the patient as a high-risk pregnancy and should administer amphotericin B. Although the presented results were favorable to monotherapy with amphotericin B and to its association with flucytosine, as well as to monotherapy with fluconazole or itraconazole, only randomized controlled trials will be able to determine the best significantly effective therapeutics for cryptococcosis in pregnant women

In vitro antifungal susceptibility of Candida spp. oral isolates from HIV-positive patients and control individuals

Oropharyngeal candidiasis is the most common fungal infection among HIV-positive patients. This condition can be treated with either systemic or topical antifungal agents; treatments are usually indicated empirically on the basis of clinical data. The knowledge of in vitro antifungal susceptibility is important to determine correct therapeutic guides for the treatment of fungal infections. Therefore, the objective of this study was to determine the antifungal susceptibility profile of oral Candida isolates from HIV-positive patients and control individuals. Amphotericin B, fluconazole, flucytosine, nystatin and ketoconazole were tested according to the methodology of microdilution proposed by the Clinical and Laboratory Standards Institute (CLSI); results were recorded in values of minimal inhibitory concentration (MIC). A total of 71 Candida isolates from HIV-positive patients were examined with the following species represented: C. albicans (59), C. tropicalis (9), C. glabrata (1), C. guilliermondii (1) and C. krusei (1). A total of 15 Candida isolates were evaluated from control individuals comprised of 11 C. albicans and 4 C. tropicalis samples. Our results demonstrated that the tested antifungal agents showed good activity for most isolates from both groups; however, variability in MIC values among isolates was observed.

Treatment of severe chromoblastomycosis with itraconazole and 5-flucytosine association / Tratamento de cromoblastomicose severa com a associação itraconazole e 5-flucitosina

Chromoblastomycosis is a chronic human melanized fungi infection of the subcutaneous tissue caused by traumatic inoculation of a specific group of dematiaceous fungi through the skin, often found in barefooted agricultural workers, in tropical and subtropical climate countries. We report the case of a male patient presenting a slow-growing pruriginous lesion on the limbs for 20 years, mistreated over that time, which was diagnosed and successfully treated as chromoblastomycosis. Besides the prevalence of this disease, treatment is still a clinical challenge.

Cromoblastomicose é uma infecção fúngica crônica do tecido subcutâneo causada pela inoculação traumática de um grupo específico de fungos através da pele, encontrados eventualmente em trabalhadores do campo descalços em países de clima tropical e subtropical. Relatamos aqui o caso de um paciente do sexo masculino com uma lesão dermatológica de crescimento lento e pruriginosa nos membros inferiores por 20 anos, diagnosticada e tratada com sucesso para cromoblastomicose. Apesar da prevalência desta doença em nossa região, o tratamento ainda é um desafio.

Comparison of ATB FUNGUS 2 and VITEK-2 Antifungal Susceptibility (AST-YS01) Tests for Candida Species Isolated from Blood Culture / 대한임상미생물학회지

BACKGROUND: The VITEK-2 yeast susceptibility test (AST-YS01; bioMerieux, Hazelwood, MO, USA) has recently been introduced as a fully automated, commercial antifungal susceptibility test system that determines MIC endpoints spectrophotometrically, thereby eliminating subjective errors. We compared the ATB FUNGUS 2 (bioMerieux) and VITEK-2 (AST-YS01) systems to the CLSI M27 method for susceptibility testing of Candida isolates. METHODS: We tested 59 Candida species that were isolated from blood cultures at Wonju Christian Hospital between September 2008 and August 2009. We compared MIC results for amphotericin B, flucytosine, fluconazole and voriconazole using the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests to those obtained by the CLSI M27 broth microdilution method. RESULTS: Within two-fold dilutions of MICs, the agreement of the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests with the CLSI method according to antifungal agents were: amphotericin B, 100% vs. 100% flucytosine, 100% vs. 100% fluconazole, 83.6% vs. 98.3% and voriconazole, 83.6% vs. 96.7%, respectively. The categorical discrepancies for fluconazole and voriconazole were 20.4% and 18.6% for ATB FUNGUS 2, and 6.8% and 0% for VITEK-2 (ASTYS01). There were no major errors for fluconazole and voriconazole in either ATB FUNGUS 2 or VITEK-2 (AST-YS01) tests. CONCLUSION: The VITEK-2 system (AST-YS01) appears to be rapid and highly correlative with the CLSI method, suggesting that it is effective for antifungal susceptibility testing for Candida species in clinical settings.

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.

Antimicóticos de uso sistémico: ¿con qué opciones terapéuticas contamos? / Systemic antifungals: which therapeutic options do we have?

La prevalencia de infecciones fúngicas invasivas ha aumentado en las últimas tres décadas debido al aumento de huéspedes inmunocomprometidos. Durante muchos años la anfotericina B y la flucitosina fueron los únicos antifúngicos disponibles para el tratamiento de estas micosis. Afortunadamente, en la última década el arsenal de antifúngicos se ha ampliado, lo que provee nuevas alternativas terapéuticas para los pacientes afectados. El objetivo de este artículo es resumir las características farmacológicas de los antifúngicos sistémicos tradicionales (anfotericina. flucitosina, itraconazol y fluconazol) y de los agentes antimicóticos de uso reciente: los nuevos triazoles (voriconazol, posaconazol) y las equinocandinas (caspofungina. micafungina y anidulofungina).

The prevalence of invasive fungal infections has increased over the past three decades owing to the increasing numbers of immunocompromised hosts. For many years, amphotericin Band flucytosine were the only available antifungal agents for invasive fungal infections. Fortunately, the antifungal drugs has increased, providing new therapeutic options for these patients. The purpose of this article is to summarize the pharmacologic profile of traditional antifungal drugs (amphotericin, flucytosine, itraconazole, fluconazole) as well as the ones recently licensed: the new triazoles (voriconazole, posaconazole) and the echinocandins (caspofungin, micafungin, anidulafungin).

Pharmacokinetics and the bystander effect in CD::UPRT/5-FC bi-gene therapy of glioma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cytosine deaminase (CD) converts 5-fluorocytosine (5-FC) to 5-fluorouracil (5-FU) in CD/5-FC gene therapy, 5-FU will be mostly converted into nontoxic beta-alanine without uracil phosphoribosyltransferase (UPRT). UPRT catalyzes the conversion of 5-FU to 5-fluorouridine monophosphate, which directly kills CD::UPRT-expressing cells and surrounding cells via the bystander effect. But the pharmacokinetics and the bystander effect of CD::UPRT/5-FC has not been verified in vivo and in vitro. Before the CD::UPRT/5-FC bi-gene therapy system is used in clinical trial, it is essential to monitor the transgene expression and function in vivo. Thus, we developed a preclinical tumor model to investigate the feasibility of using (19)F-magnetic resonance spectroscopy ((19)F-MRS) and optical imaging to measure non-invasive CD and UPRT expression and its bystander effect.</p><p><b>METHODS</b>C6 and C6-CD::UPRT cells were cultured with 5-FC. The medium, cells and their mixture were analyzed by (19)F-MRS. Rats with intracranial xenografted encephalic C6-CD::UPRT glioma were injected intraperitoneally with 5-FC and their (19)F-MRS spectra recorded. Then the pharmacokinetics of 5-FC was proved. Mixtures of C6 and C6-CD::UPRT cells at different ratios were cultured with 5-FC and the cytotoxic efficacy and survival rate of cells recorded. To determine the mechanism of the bystander effect, the culture media from cell comprising 25% and 75% C6-CD::UPRT cells were examined by (19)F-MRS. A comparative study of mean was performed using analysis of variance (ANOVA).</p><p><b>RESULTS</b>(19)F-MRS on samples from C6-CD::UPRT cells cultured with 5-FC showed three broad resonance signals corresponding to 5-FC, 5-FU and fluorinated nucleotides (F-Nuctd). For the C6 mixture, only the 5-FC peak was detected. In vivo serial (19)F-MRS spectra showed a strong 5-FC peak and a weak 5-FU peak at 20 minutes after 5-FC injection. The 5-FU concentration reached a maximum at about 50 minutes. The F-Nuctd signal appeared after about 1 hour, reached a maximum at around 160 minutes, and was detectable for several hours. At a 10% ratio of C6-CD::UPRT cells, the survival rate was (79.55 +/- 0.88)% (P < 0.01). As the C6-CD::UPRT ratio increased, the survival rate of the cells decreased. (19)F-MRS showed that the signals for 5-FU and F-Nuctd in the culture medium increased as the ratio of C6-CD::UPRT in the mixture increased.</p><p><b>CONCLUSIONS</b>(19)F-MRS studies indicated that C6-CD::UPRT cells could effectively express CD and UPRT enzymes. The CD::UPRT/5-FC system showed an obvious bystander effect. This study demonstrated that CD::UPRT/5-FC gene therapy is suitable for 5-FC to F-Nuctd metabolism; and (19)F-MRS can monitor transferred CD::UPRT gene expression and catalysis of substrates noninvasively, dynamically and quantitatively.</p>

The Optimal Wavelength of Spectrophotometric Broth Microdilution Antifungal Susceptibility Test for Flucytosine and Three Azoles / 대한진단검사의학회지

BACKGROUND: There is no guideline for the appropriate wavelength at which to measure the optical density (OD) value in broth microdilution antifungal susceptibility testing, although a spectrophotometric reading method is commonly used. The present study aimed to analyze the difference in the OD values over the range of visible light and to ascertain the optimal wavelength for the spectrophotometric method of microdilution testing. METHODS: We measured the OD of background blank controls of broth medium, antifungal agents, and inocula of five type strains using a Synergy HT multi-detection microplate reader at 5-nm intervals from 380 nm to 760 nm. We also estimated the OD differences between the 50% of growth control and blank control. RESULTS: The OD of the blank control showed a parabola shape with two peaks and steadily decreased at longer wavelengths. The curves of the antifungal agent were similar to those of blank controls, and the influence of each antifungal agent on the OD was minimal. For the difference in OD between 50% of growth control and the blank control, the curve was the opposite of the blank control, and the OD increased steadily at the wavelengths above 600 nm. CONCLUSIONS: The range between 600 nm and 700 nm was the optimal wavelength for broth microdilution antifungal susceptibility testing, although any wavelength within the visible light spectrum can be used.

Fatal cerebral abscess caused by Cladophialophora bantiana.

Primary cerebral phaeohyphomycosis is caused by pigmented fungi that exhibit distinct neurotropism often in immunocompetent individuals. A 20-yr-old male presented with multiple brain abscess which was subsequently proven microbiologically to be due to Cladophialophora Bantiana. In spite of near total excision and appropriate antifungal agents succumbed to his illness. We report this case to highlight its rarity and high mortality in an immunocompetent host. There is no initial clinical or laboratory feature that makes a preoperative diagnosis possible and relies on microbiological confirmation.