Lycorine Alkaloid and Crinum americanum L. (Amaryllidaceae) Extracts Display Antifungal Activity on Clinically Relevant Candida Species.

Candida species are the main fungal agents causing infectious conditions in hospital patients. The development of new drugs with antifungal potential, increased efficacy, and reduced toxicity is essential to face the challenge of fungal resistance to standard treatments. The aim of this study is to evaluate the in vitro antifungal effects of two crude extracts of Crinum americanum L., a rich alkaloid fraction and lycorine alkaloid, on the Candida species. As such, we used a disk diffusion susceptibility test, determined the minimum inhibitory concentration (MIC), and characterized the components of the extracts using Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (ESI FT-ICR MS). The extracts were found to have antifungal activity against various Candida species. The chemical characterization of the extracts indicated the presence of alkaloids such as lycorine and crinine. The Amaryllidaceae family has a promising antifungal potential. Furthermore, it was found that the alkaloid lycorine directly contributes to the effects that were observed for the extracts and fraction of C. americanum.

Faster Cryptococcus Melanization Increases Virulence in Experimental and Human Cryptococcosis.

Cryptococcus spp. are human pathogens that cause 181,000 deaths per year. In this work, we systematically investigated the virulence attributes of Cryptococcus spp. clinical isolates and correlated them with patient data to better understand cryptococcosis. We collected 66 C. neoformans and 19 C. gattii clinical isolates and analyzed multiple virulence phenotypes and host-pathogen interaction outcomes. C. neoformans isolates tended to melanize faster and more intensely and produce thinner capsules in comparison with C. gattii. We also observed correlations that match previous studies, such as that between secreted laccase and disease outcome in patients. We measured Cryptococcus colony melanization kinetics, which followed a sigmoidal curve for most isolates, and showed that faster melanization correlated positively with LC3-associated phagocytosis evasion, virulence in Galleria mellonella and worse prognosis in humans. These results suggest that the speed of melanization, more than the total amount of melanin Cryptococcus spp. produces, is crucial for virulence.

Inhibitory effects of Lactobacillus casei Shirota against both Candida auris and Candida spp. isolates that cause vulvovaginal candidiasis and are resistant to antifungals.

BACKGROUND: Vulvovaginal candidiasis (VVC), the second leading cause of genital infection in women of reproductive age, is caused by yeasts of the genus Candida. Treatment is usually empirical and performed with azoles, which have shown increasing ineffectiveness due to resistance from these species. This therapeutic challenge has led to the search for new treatment strategies. Lactobacillus spp. produce several components with microbicidal effects, such as lactic acid. These species are the main components of a healthy vaginal microbiota and have been used as probiotics. The aim of this work was to investigate the in vitro inhibitory effects of Lactobacillus casei Shirota on both the Candida spp. that cause VVC and on C. auris. METHODS: The microbicidal effects of L. casei Shirota on the main VVC-causing species, C. albicans, C. tropicalis, C. norvegensis and C. parapsilosis, in addition to C. auris were investigated by counting the Colony-forming Units (CFUs) after cocultivation. The antifungal activity of lactic acid against these Candida strains was assessed using the microtiter broth dilution method to determine the minimum inhibitory concentrations (MICs). The effects of L. casei Shirota on hyphal and early biofilm formation was measured by optical microscopy. RESULTS: L. casei Shirota showed inhibitory action against all tested Candida spp., ranging from 66.9 to 95.6% inhibition depending on the species. This inhibition is possibly related to the production of lactic acid, since lactic acid has shown microbicidal action against these same Candida spp. at a concentration of 5 mg/mL, which corresponds to half of the normal physiological concentration. In addition, L. casei Shirota was able to reduce the formation of C. albicans hyphae and early biofilms, showing strong anti-Candida effects. CONCLUSIONS: These results suggest that L. casei Shirota has antifungal activity against the Candida species that cause VVC. L. casei also has microbicidal action against C. auris.

Vulvovaginal candidiasis and current perspectives: new risk factors and laboratory diagnosis by using MALDI TOF for identifying species in primary infection and recurrence.

Vulvovaginal candidiasis (VVC), considered the second cause of genital infection among women, has pathogenic mechanisms still to be elucidated and unknown risk factors. Prevalence studies with laboratory diagnosis (at first diagnosis and recurrence) are uncommon, especially using MALDI TOF, used in this clinical, epidemiological, and laboratory study for evaluating candidiasis, and identifying unknown risk factors. To obtain clinical and epidemiological data, patients were questioned, and there was material collection. Samples collected were identified by using phenotypic and presumptive methods and confirmed by MALDI TOF. This study analyzed 278 patients, divided into symptomatic (n = 173) and asymptomatic (n = 105) groups. Regarding the main candidiasis symptoms (discharge, itching, and burning), only 50.3% of patients described these concomitant symptoms, showing a positive predictive value of 67.8%. Regarding the risk factors investigated, there was a statistical correlation between candidiasis and dairy products, gut transit, contraceptive use, respiratory allergy, and panty liners, describing new risk factors related to intestinal and vaginal dysbiosis. After Candida species analysis and confirmation, the primary prevalence was 80.9% (Candida albicans), 15.2% (non-albicans), 1% (Rhodotorula mucilaginosa), and 1.9% (unidentified species). In recurrence, the prevalence was 66.7% (C. albicans) and 33.3% (non-albicans). The presence of symptoms has low positive predictive value for the diagnosis of candidiasis, even when considering the classic triad of symptoms. Laboratory identification of yeast species is essential for correct treatment, preventing the resistance to antifungals and the high recurrence. In addition, dairy products and bowel habits, both related to intestinal and vaginal dysbiosis, may be associated with VVC.

Investigação de surto de Histoplasmose pulmonar aguda entre bombeiros em Brazlândia, Distrito Federal, 2017 / Investigation of acute histoplasmosis outbreak among firefighters, Distrito Federal, 2017

Objetivos: Investigar o surto de histoplasmose em bombeiros no Distrito federal/DF, ocorrido em junho de 2017. Métodos: Realizou-se um estudo de coorte por meio das entrevistas realizadas com os bombeiros mediante um questionário semiestruturado. Considerou-se infectado o bombeiro que apresentou tomografia de tórax sugestiva de histoplasmose ou reagente nos testes de imunodifusão e/ou Western blot. Coletou-se amostra ambiental e realizou-se Nested PCR específico para Histoplasma capsulatum. Resultados: Entre 35 bombeiros, 94,3% eram homens; com a mediana de idade de 37 (24-45) anos, 28 foram classificados como infectados. A média de permanência dentro da caverna foi 25 minutos. O fator de risco associado à infecção foi o ato de entrar na caverna (RR=3,86; RA=71,6; p<0,02). Entre 14 amostras ambientais, 50% foram positivas para H. capsulatum. Conclusão: Confirmou-se o surto de histoplasmose de bombeiros em Brazlândia-DF, e foram tomadas ações como a interdição da caverna e o tratamento dos bombeiros.

Objectives: To nvestigate the outbreak of histoplasmosis in firefighters in Federal District/DF, which occurred in June 2017. Methods: A cohort study was conducted through interviews with firefighters by means of a semi-structured questionnaire. Firefighters who presented chest tomography suggestive of histoplasmosis or reacted to immunodiffusion and/or Western blot tests were considered infected. Environmental samples were collected and Nested PCR specific for Histoplasma capsulatum was performed. Results: Among 35 firefighters, 94.3% were men; with a median age of 37 (24-45) years, 28 were classified as infected. The average length of stay inside the cave was 25 minutes. The risk factor associated with infection was the act of entering the cave (RR = 3.86, RA = 71.6, p <0.02). Among 14 environmental samples, 50% were positive for H. capsulatum. Conclusion: The outbreak of histoplasmosis in firefighters in Brazlândia-DF was confirmed, and actions were taken such as banning the cave and treating the firefighters

Activity of crude extracts from Brazilian cerrado plants against clinically relevant Candida species.

BACKGROUND: Medicinal plants have traditionally been used in many parts of the world as alternative medicine. Many extracts and essential oils isolated from plants have disclosed biological activity, justifying the investigation of their potential antimicrobial activity. In this study, the in vitro antifungal activity of six Brazilian Cerrado medicinal plant species were evaluated against clinically relevant Candida species. METHODS: The crude extract plants were evaluated against American Type Culture Collection (ATCC) standard strains of Candida spp. using disk diffusion method and determining the minimum inhibitory concentration (MIC). The chemical study results were confirmed by HPLC method. RESULTS: All six plant species showed antifungal activity. Among the species studied, Eugenia dysenterica and Pouteria ramiflora showed significant inhibitory activity against C. tropicalis at lowest MIC value of 125 and 500 µg/disc, respectively. The Eugenia dysenterica also disclosed MIC value of 125 µg/disc against C. famata, 250 µg/disc against C. krusei and 500 µg/disc against C. guilliermondii and C. parapsilosis. Pouteria torta, Bauhinia rufa, Erythroxylum daphnites and Erythroxylum subrotundum showed activity against the yeast strains with MIC value of 1000 µg/disc. The chemical study of the most bioactive extracts of Eugenia dysenterica and Pouteria ramiflora revealed catechin derivatives and flavonoids as main components. CONCLUSIONS: All six evaluated plant species showed good antifungal potential against several Candida strains. However, E .dysenterica and P. ramiflora showed the higher inhibitory effect against the non-albicans Candida species. Our results may contribute to the continuing search of new natural occurring products with antifungal activity.

Predictors of Virologic Failure in HIV/AIDS Patients Treated with Highly Active Antiretroviral Therapy in Brasília, Brazil During 2002-2008.

Little data exists concerning the efficacy of the antiretroviral therapy in the Federal District in Brazil, therefore in order to improve HIV/AIDS patients' therapy and to pinpoint hot spots in the treatment, this research work was conducted. Of 139 HIV/AIDS patients submitted to the highly active antiretroviral therapy, 12.2% failed virologically. The significant associated factors related to unresponsiveness to the lentiviral treatment were: patients' place of origin (OR = 3.28; IC95% = 1.0-9.73; P = 0.032) and Mycobacterium tuberculosis infection (RR = 2.90; IC95% = 1.19-7.02; P = 0.019). In the logistic regression analysis, the remaining variables in the model were: patients' birthplace (OR = 3.28; IC95% = 1.10-9.73; P = 0.032) and tuberculosis comorbidity (OR = 3.82; IC95% = 1.19-12.22; P = 0.024). The patients enrolled in this survey had an 88.0% therapeutic success rate for the maximum period of one year of treatment, predicting that T CD4(+) low values and elevated viral loads at pretreatment should be particularly considered in tuberculosis coinfection, besides the availability of new antiretroviral drugs displaying optimal activity both in viral suppression and immunological reconstitution.

Prevalência e suscetibilidades bacterianas das infecções comunitárias do trato urinário, em Hospital Universitário de Brasília, no período de 2001 a 2005 / Prevalence and bacterial susceptibility of community acquired urinary tract infection in University Hospital of Brasília, 2001 to 2005

A infecção do trato urinário é uma das afecções mais comuns da clínica médica, sendo mandatório o conhecimento epidemiológico da mesma e do perfil de sensibilidade dos agentes etiológicos. O estudo teve como objetivo identificar os agentes etiológicos mais freqüentes e o perfil de sensibilidade aos antimicrobianos das bactérias isoladas de uroculturas de pacientes ambulatoriais atendidos no Hospital Universitário de Brasília no período de 2001 a 2005. Foram analisadas 2.433 uroculturas positivas realizadas no laboratório de microbiologia do Hospital Universitário de Brasília. A Escherichia coli foi a bactéria mais isolada (62,4 por cento), seguida de Klebsiella pneumoniae (6,8 por cento) e Proteus mirabillis (4,7 por cento). A Escherichia coli apresentou maior sensibilidade à amicacina (98,6 por cento), gentamicina (96,2 por cento), nitrofurantoína (96,3 por cento), e às quinolonas ciprofloxacina (90,9 por cento) e norfloxacina (89,8 por cento), com baixa sensibilidade ao sulfametoxazol-trimetoprima (50,6 por cento). As outras bactérias apresentaram similar padrão de sensibilidade. Em conclusão, a Escherichia coli foi a bactéria mais isolada, sendo altamente sensível aos amiglicosídeos, nitrofurantoína e quinolonas.

Urinary tract infection is among the most common infectious diseases in clinical medicine, and knowledge of its epidemiology and the sensitivity profile of the etiological agents is mandatory. The aim of this study was to identify the most frequent etiological agents and the profile of sensitivity to antimicrobial agents of the bacteria isolated from urine cultures from outpatients at the University Hospital of Brasília between 2001 and 2005. From analyses at the hospital’s microbiology laboratory, there were 2,433 positive urine cultures. Escherichia coli was the most commonly isolated bacteria (62.4 percent), followed by Klebsiella pneumoniae (6.8 percent) and Proteus mirabilis (4.7 percent). Escherichia coli showed the highest sensitivity to amikacin (98.6 percent), gentamicin (96.2 percent), nitrofurantoin (96.3 percent) and the quinolones ciprofloxacin (90.9 percent) and norfloxacin (89.8 percent), with low sensitivity to sulfamethoxazole-trimethoprim (50.6 percent). The others bacteria presented similar sensitivity profiles. In conclusion, Escherichia coli was the most commonly isolated bacteria, and it was highly sensitive to aminoglycosides, nitrofurantoin and quinolones.

[Prevalence and bacterial susceptibility of community acquired urinary tract infection in University Hospital of Brasília, 2001 to 2005]. / Prevalência e suscetibilidades bacterianas das infecções comunitárias do trato urinário, em Hospital Universitário de Brasília, no período de 2001 a 2005.

Urinary tract infection is among the most common infectious diseases in clinical medicine, and knowledge of its epidemiology and the sensitivity profile of the etiological agents is mandatory. The aim of this study was to identify the most frequent etiological agents and the profile of sensitivity to antimicrobial agents of the bacteria isolated from urine cultures from outpatients at the University Hospital of Brasília between 2001 and 2005. From analyses at the hospitals microbiology laboratory, there were 2,433 positive urine cultures. Escherichia coli was the most commonly isolated bacteria (62.4%), followed by Klebsiella pneumoniae (6.8%) and Proteus mirabilis (4.7%). Escherichia coli showed the highest sensitivity to amikacin (98.6%), gentamicin (96.2%), nitrofurantoin (96.3%) and the quinolones ciprofloxacin (90.9%) and norfloxacin (89.8%), with low sensitivity to sulfamethoxazole-trimethoprim (50.6%). The others bacteria presented similar sensitivity profiles. In conclusion, Escherichia coli was the most commonly isolated bacteria, and it was highly sensitive to aminoglycosides, nitrofurantoin and quinolones.