Fatores de risco da leucemia viral felina em São Paulo, Brazil

The aim of this study was to identify risk factors for feline leukemia virus (FeLV) infection in cats (n = 812) from the city of São Paulo. Information on age, gender, outdoor access, reproductive status, origin and number of potential contacts were obtained for each animal. Direct immunofluorescence test was used to identify the infected cats. Fifty cats (6.2 %) were positive for FeLV infection. The risk factors identified were "outdoor access" (OR = 47.2; p < 0.001), "having been rescued from the street" (OR = 3.221; p = 0.008) or being three to six year old (OR = 3.046; p = 0.009); the most important risk factor was free outdoor access. A predictive model for FeLV infection was built based on the results of the multivariate analysis. Cats with free outdoor access are more predisposed to infection, with 18% more chances of becoming infected. If the animal is one to three year old, the probability increases, reaching 34%. If the cat is exposed to these three risk factors, the probability of infection is even higher (63%). When analyzed together or as isolated risk factors, the age and being rescued from the street represent less impact on the spreading of the FeLV, as the probability of infection for cats exposed to each of these risk factors is 1 and 4%, respectively. Thus, free roaming and outdoor access are the most important risk factors associated to FeLV infection among cats in São Paulo city and must be taken in consideration in the prevention of this retrovirus infection.O objetivo deste estudo foi o de identificar os fatores de risco para a leucemia viral felina (FeLV) em uma amostragem de 812 gatos da cidade de São Paulo, Brasil. Informações sobre idade, sexo, acesso à rua, estado reprodutivo, origem e número de contactantes foram obtidos para cada animal. Teste de imunofluorescência direto para a pesquisa de antígeno viral em esfregaço de sangue periférico foi utilizado para a identificação dos felinos infectados. Foram encontrados 51 gatos (6,2%) positivos para a infecção. Os fatores de risco identificados foram "acesso a rua" (OR = 47,2; p &lt; 0,001), "ter sido resgatado da rua" (OR = 3,221; p = 0,008) e "ter idade entre 3 e 6 anos" (OR = 3,046; p = 0,009), sendo o "livre acesso à rua" o fator de risco mais importante. Foi elaborado um modelo preditivo para a infecção pelo FeLV, baseando-se nos resultados da análise multivariada. Gatos com acesso livre à rua apresentam 18% mais chances de se infectarem e se estiverem na faixa etária entre 3 e 6 anos de idade o risco aumenta para 34%. Se o gato estiver exposto aos três fatores de risco, a probabilidade de infecção é ainda mais alta, de 63%. Quando analisados em conjunto ou como fatores de risco isolados, a idade e o fato de "ter sido resgatado da rua" possuem menor impacto na disseminação de FeLV, já que a probabilidade de infecção para os gatos expostos a cada um desses fatores é de 1% e de 4%, respectivamente. Assim, o acesso livre a rua e ter sido resgatado da rua foram os fatores de risco mais importantes associados com a infecção pelo FeLV na cidade de São Paulo e devem ser levados em consideração na profilaxia da leucemia viral felina

Probiotics for Prevention and Treatment of Candidiasis and Other Infectious Diseases: Lactobacillus spp. and Other Potential Bacterial Species

The resident microbiota in the human body, such as the oral cavity, gastrointestinal tract and genitourinary tract, is able to provide resistance to disease. However, imbalances in the microbial components can promote the growth of opportunistic microorganisms, such as yeasts of genus Candida. Fungal infections present as a major cause of infectious diseases and the microorganisms of genus Candida are the most frequently isolated pathogenic fungi in human fungal infections. Bacillus spp. and Lactobacillus spp. are bacteria that have probiotic effects used in commercially available products and in studies that aim for the development of probiotics able to inhibit the microbial pathogenicity and restore the balance of resident microbiota. Thus, with increasing fungus resistance to the use of antifungal agents, which are capable of causing serious side effects to the host organism unable to destroy the target microorganism, it becomes important to develop therapeutic and/or prophylactic alternatives that have a different and an effective mechanism of action with capacity to combat fungal infections without harming the patient. Probiotic bacteria provide an alternative strategy for the prevention and treatment of candidiasis and other infectious diseases

Presence of Candida spp. in the oral cavity of heart transplantation patients

Candida spp. can lead to infections or even fungal sepsis particularly among immunocompromized individuals. OBJECTIVE: The aim of the present study was to analyze the presence of Candida spp. among patients subjected to orthotopic heart transplantation. MATERIAL AND METHODS: Oral rinses from 50 patients subjected to orthotopic heart transplantation, aged 13 to 70 years, 40 males and 10 females, were examined. Sex-age-oral conditions matched-control included 50 individuals who were not subjected to any kind of transplantation and were not immunocompromized for any other reason. Counts of yeasts were expressed as median values of logarithm of cfu/mL and were statistically compared by Mann-Whitney's test. The heart transplant and control groups were compared for the presence of Candida spp. by chi-square test (

Oral Candida albicans isolates from HIV-positive individuals have similar in vitro biofilm-forming ability and pathogenicity as invasive Candida isolates

Background: Candida can cause mucocutaneous and/or systemic infections in hospitalized and immunosuppressed patients. Most individuals are colonized by Candida spp. as part of the oral flora and the intestinal tract. We compared oral and systemic isolates for the capacity to form biofilm in an in vitro biofilm model and pathogenicity in the Galleria mellonella infection model. The oral Candida strains were isolated from the HIV patients and included species of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, C. norvegensis, and C. dubliniensis. The systemic strains were isolated from patients with invasive candidiasis and included species of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. lusitaniae, and C. kefyr. For each of the acquired strains, biofilm formation was evaluated on standardized samples of silicone pads and acrylic resin. We assessed the pathogenicity of the strains by infecting G. mellonella animals with Candida strains and observing survival.Results: The biofilm formation and pathogenicity in Galleria was similar between oral and systemic isolates. The quantity of biofilm formed and the virulence in G. mellonella were different for each of the species studied. on silicone pads, C. albicans and C. dubliniensis produced more biofilm (1.12 to 6.61 mg) than the other species (0.25 to 3.66 mg). However, all Candida species produced a similar biofilm on acrylic resin, material used in dental prostheses. C. albicans, C. dubliniensis, C. tropicalis, and C. parapsilosis were the most virulent species in G. mellonella with 100% of mortality, followed by C. lusitaniae (87%), C. novergensis (37%), C. krusei (25%), C. glabrata (20%), and C. kefyr (12%).Conclusions: We found that on silicone pads as well as in the Galleria model, biofilm formation and virulence depends on the Candida species. Importantly, for C. albicans the pathogenicity of oral Candida isolates was similar to systemic Candida isolates, suggesting that Candida isolates have similar biofilm-forming ability and virulence regardless of the infection site from which it was isolated

Susceptibility of Candida albicans and Candida dubliniensis to erythrosine- and LED-mediated photodynamic therapy

AbstractThe effect of erythrosine- and LED-mediated photodynamic therapy (PDT) on planktonic cultures and biofilms of Candida albicans and Candida dubliniensis was evaluated. Planktonic cultures of standardized suspensions (106cells/mL) of C. albicans and C. dubliniensis were treated with erythrosine concentrations of 0.39–200μM and LEDs in a 96-well microtiter plate. Biofilms formed by C. albicans and C. dubliniensis in the bottom of a 96-well microtiter plate were treated with 400μM erythrosine and LEDs. After PDT, the biofilms were analysed by scanning electron microscopy (SEM). The antimicrobial effect of PDT against planktonic cultures and biofilms was verified by counting colony-forming units (CFU/mL), and the data were submitted to analysis of variance and the Tukey test (P<0.05). C. albicans and C. dubliniensis were not detectable after PDT of planktonic cultures with erythrosine concentrations of 3.12μM or higher. The CFU/mL values obtained from biofilms were reduced 0.74 log10 for C. albicans and 0.21 log10 for C. dubliniensis. SEM revealed a decrease in the quantity of yeasts and hyphae in the biofilm after PDT. In conclusion, C. albicans and C. dubliniensis were susceptible to erythrosine- and LED-mediated PDT, but the biofilms of both Candida species were more resistant than their planktonic counterparts

Oral colonization by yeasts in HIV-positive patients in Brazil

INTRODUCTION: In HIV-infected patients, colonization of the oral cavity by potential pathogenic yeast may lead to development of systemic fungemia. We evaluated the prevalence of yeast in the oral cavity of Brazilian HIV-positive patients and verified whether or not the species characterized were enzymatically active. Furthermore, the species identified were tested for their susceptibility to antifungal treatment. METHODS: Patient saliva and oropharyngeal candidiasis samples were collected from 60 seropositive HIV patients and identified by the API20C system. Enzymatic activity was evaluated by the production of proteinase and phospholipase. Susceptibility to antifungal treatments were determined using the broth microdilution method. RESULTS: the most commonly isolated species were C. albicans (51.56%) followed by non-albicans Candida species (43.73%), Trichosporon mucoides (3.12%) and Kodamaea ohmeri (1.56%). Oral colonization by association of different species was observed in 42% of the patients. Enzymatic activity was verified in most of species isolated, except for C. glabrata, C. lusitaniae and C. guilliermondii. Resistance to Fluconazole and Amphotericin B was observed in isolates of C. albicans, C. glabrata, C. parapsilosis, C. krusei, and K. ohmeri. CONCLUSION: HIV-positive patients are orally colonized by single or multiple species of yeast that are occasionally resistant to Fluconazole or Amphotericin B.INTRODUÇÃO: Em pacientes infectados pelo HIV, a colonização da cavidade bucal por leveduras patogênicas pode levar ao desenvolvimento de fungemias. No presente estudo, avaliamos a prevalência de leveduras na cavidade bucal de pacientes HIV-positivos e verificamos se as espécies isoladas foram enzimaticamente ativas. Além disso, as espécies identificadas foram testadas quanto à suscetibilidade a antifúngicos. MÉTODOS: Amostras de saliva e de candidose orofaríngea foram coletadas de 60 pacientes soropositivos para HIV e identificados pelo sistema API20C. A atividade enzimática foi avaliada pela produção de proteinase e fosfolipase. A suscetibilidade a antifúngicos foi determinada utilizando o método de microdiluição em caldo. RESULTADOS: As espécies mais comumente isoladas foram C. albicans (51,56%), seguido por espécies de Candida não-albicans (43,73%), Trichosporon mucoides (3,12%) e Kodamaea ohmeri (1,56%). A colonização bucal por associação de diferentes espécies foi observada em 42% dos pacientes. A atividade enzimática foi verificada na maioria das espécies isoladas, com exceção de C. glabrata, C. lusitaniae e C. guilliermondii. Resistência ao fluconazol e anfotericina B foi observada em isolados de C. albicans, C. glabrata, C. parapsilosis, C. krusei, e K. ohmeri. CONCLUSÃO: Os pacientes HIV-positivos são colonizados por espécies únicas ou múltiplas de levedura que ocasionalmente são resistentes ao fluconazol ou anfotericina B

Photodynamic and Antibiotic Therapy Impair the Pathogenesis of Enterococcus faecium in a Whole Animal Insect Model

Enterococcus faecium has emerged as one of the most important pathogens in healthcare-associated infections worldwide due to its intrinsic and acquired resistance to many antibiotics, including vancomycin. Antimicrobial photodynamic therapy (aPDT) is an alternative therapeutic platform that is currently under investigation for the control and treatment of infections. PDT is based on the use of photoactive dye molecules, widely known as photosensitizer (PS). PS, upon irradiation with visible light, produces reactive oxygen species that can destroy lipids and proteins causing cell death. We employed Galleria mellonella (the greater wax moth) caterpillar fatally infected with E. faecium to develop an invertebrate host model system that can be used to study the antimicrobial PDT (alone or combined with antibiotics). In the establishment of infection by E. faecium in G. mellonella, we found that the G. mellonella death rate was dependent on the number of bacterial cells injected into the insect hemocoel and all E. faecium strains tested were capable of infecting and killing G. mellonella. Antibiotic treatment with ampicillin, gentamicin or the combination of ampicillin and gentamicin prolonged caterpillar survival infected by E. faecium (P = 0.0003, P = 0.0001 and P = 0.0001, respectively). In the study of antimicrobial PDT, we verified that methylene blue (MB) injected into the insect followed by whole body illumination prolonged the caterpillar survival (P = 0.0192). Interestingly, combination therapy of larvae infected with vancomycin-resistant E. faecium, with antimicrobial PDT followed by vancomycin, significantly prolonged the survival of the caterpillars when compared to either antimicrobial PDT (P = 0.0095) or vancomycin treatment alone (P = 0.0025), suggesting that the aPDT made the vancomycin resistant E. faecium strain more susceptible to vancomycin action. In summary, G. mellonella provides an invertebrate model host to study the antimicrobial PDT and to explore combinatorial aPDT-based treatments