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1.
Microbiol Res ; 230: 126330, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31541842

RESUMO

Glycoconjugates found on cell walls of Candida species are fundamental for their pathogenicity. Laborious techniques have been employed to investigate the sugar composition of these microorganisms. Herein, we prepared a nanotool, based on the fluorescence of quantum dots (QDs) combined with the specificity of Cramoll lectin, to evaluate glucose/mannose profiles on three Candida species. The QDs-Cramoll conjugates presented specificity and bright fluorescence emission. The lectin preserved its biological activity after the conjugation process mediated by adsorption interactions. The labeling of Candida species was analyzed by fluorescence microscopy and quantified by flow cytometry. Morphological analyses of yeasts labeled with QDs-Cramoll conjugates indicated that C. glabrata (2.7 µm) was smaller when compared to C. albicans (4.0 µm) and C. parapsilosis sensu stricto (3.8 µm). Also, C. parapsilosis population was heterogeneous, presenting rod-shaped blastoconidia. More than 90% of cells of the three species were labeled by conjugates. Inhibition and saturation assays indicated that C. parapsilosis had a higher content of exposed glucose/mannose than the other two species. Therefore, QDs-Cramoll conjugates demonstrated to be effective fluorescent nanoprobes for evaluation of glucose/mannose constitution on the cell walls of fungal species frequently involved in candidiasis.


Assuntos
Candida/química , Corantes Fluorescentes/química , Glucose/análise , Lectinas/química , Manose/análise , Microscopia de Fluorescência/métodos , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candida/metabolismo , Candidíase/diagnóstico , Candidíase/microbiologia , Parede Celular/química , Parede Celular/metabolismo , Glucose/metabolismo , Humanos , Manose/metabolismo , Microscopia de Fluorescência/instrumentação , Nanopartículas/química , Pontos Quânticos/química
2.
J Appl Microbiol ; 128(1): 88-101, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31509623

RESUMO

AIMS: Staphylococcus aureus (a bacterial pathogen) and Candida sp. (opportunistic fungi) are two clinically relevant biofilm-forming microbes responsible for a majority of community- and nosocomial-acquired infections. Dual species biofilm formation between S. aureus and Candida sp. extremely enhances the antimicrobial resistance of the micro-organisms and is difficult to treat with antibiotic therapy. Hence, it is crucial to explore new antimicrobial agents. Auranofin (AF) is a mixed ligand gold compound and has recently been repurposed as an antibacterial and antifungal agent. However, the effects of AF against dual species biofilm have remained largely untested. METHODS AND RESULTS: In the present study, by constructing biofilms on microplates and urinary catheter surfaces, AF showed strong planktonic cells and biofilm inhibitory effects against mono- and dual culture models of S. aureus and Candida albicans but only exhibited moderate antibiofilm effects on Candida parapsilosis. Auranofin could be synergistic with subminimal inhibitory concentrations of amphotericin B against S. aureus + C. albicans/C. parapsilosis dual biofilms. Auranofin also showed effective antimicrobial effects on vancomycin-resistant strains. However, the antimicrobial effects of AF were decreased in the presence of heat-inactivated foetal bovine serum. CONCLUSIONS: In summary, AF could effectively inhibit S. aureus and C. albicans mono- and dual biofilm formation in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Coexistence between Staphylococcus aureus and Candida sp. in dual biofilms leads to increased resistance to some conventionally used antimicrobials, indicating a need for alternative treatments. This study demonstrates the potential for the Au-containing compound AF in the treatment of dual biofilm infections and encourages further investigation of this treatment for clinical use.


Assuntos
Anti-Infecciosos/farmacologia , Auranofina/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Anfotericina B/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Técnicas de Cocultura , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Especificidade da Espécie , Staphylococcus aureus/crescimento & desenvolvimento , Cateteres Urinários/microbiologia
3.
PLoS One ; 14(12): e0218360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887112

RESUMO

Microbial ingredients such as Candida utilis yeast are known to be functional protein sources with immunomodulating effects whereas soybean meal causes soybean meal-induced enteritis in the distal intestine of Atlantic salmon (Salmo salar L.). Inflammatory or immunomodulatory stimuli at the local level in the intestine may alter the plasma proteome profile of Atlantic salmon. These deviations can be helpful indicators for fish health and, therefore potential tools in the diagnosis of fish diseases. The present work aimed to identify local intestinal tissue responses and changes in plasma protein profiles of Atlantic salmon fed inactive dry Candida utilis yeast biomass, soybean meal, or combination of soybean meal based diet with various inclusion levels of Candida utilis. A fishmeal based diet was used as control diet. Inclusion of Candida utilis yeast to a fishmeal based diet did not alter the morphology, immune cell population or gene expression of the distal intestine. Lower levels of Candida utilis combined with soybean meal modulated immune cell populations in the distal intestine and reduced the severity of soybean meal-induced enteritis, while higher inclusion levels of Candida utilis were less effective. Changes in the plasma proteomic profile revealed differences between the diets but did not indicate any specific proteins that could be a marker for health or disease. The results suggest that Candida utilis does not alter intestinal morphology or induce major changes in plasma proteome, and thus could be a high-quality alternative protein source with potential functional properties in diets for Atlantic salmon.


Assuntos
Ração Animal/microbiologia , Candida/crescimento & desenvolvimento , Salmo salar/crescimento & desenvolvimento , Ração Animal/análise , Criação de Animais Domésticos/métodos , Animais , Aquicultura/métodos , Dieta , Expressão Gênica , Intestinos/fisiologia , Proteínas , Proteoma/metabolismo , Proteômica , Soja
4.
Medicine (Baltimore) ; 98(44): e17704, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689800

RESUMO

For early diagnosis and treatment of invasive candidiasis (IC), the well-known risk factors may not apply in the intensive care unit (ICU). This retrospective study identified the risk factors predicting IC and candidemia in cancer patients under intensive care after gastrointestinal surgery.Enrolled were 229 cancer patients admitted to our oncology surgical ICU after gastrointestinal surgery between January 1, 2010 and October 31, 2014.The most common types of solid gastrointestinal cancers were gastric (49.8%), colon (20.1%), and esophageal (18.3%). The percentage of patients with corrected Candida colonization index (CCI) ≥0.4 was 31.9%. IC was confirmed in 19 patients (8.3%), and the ICU mortality was 15.8%. Candida albicans accounted for 52.6% of the total number of pathogenic Candida isolates. Among patients with CCI ≥0.4, the cancers with the highest prevalence were cardiac (45%) and gastric (36%), with ICU mortalities of 20% and 4.9%, respectively. For the diagnosis of candidemia, (1-3)-ß-D-glucan (BDG) ≥80 pg/mL showed a sensitivity and specificity of 25% and 82.7%, respectively, positive and negative predictive values 6.7% and 95.7%, and area under the receiver operating characteristic curve 0.512. CCI ≥0.4 was the only significant predictor of IC, and number of organ failures was the only predictor of candidemia (P = .000 and .026).CCI ≥0.4 was the only significant risk factor predicting IC, with greater prediction of intra-abdominal candidiasis but failure to predict candidemia. Blood culture and BDG detection are recommended to supplement diagnosis. Patients may have multifocal and high-grade Candida colonization after cardiac surgery, and; therefore, are at high risk of IC, which should be taken seriously.


Assuntos
Candidemia/epidemiologia , Candidíase Invasiva/epidemiologia , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/cirurgia , APACHE , Fatores Etários , Idoso , Candida/crescimento & desenvolvimento , Estado Terminal , Feminino , Hospitais Universitários , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Estudos Retrospectivos , Fatores de Risco , Sepse/epidemiologia
5.
Molecules ; 24(17)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470602

RESUMO

The promising antimicrobial activity of essential oils (EOs) has led researchers to use them in combination with antimicrobial drugs in order to reduce drug toxicity, side effects, and resistance to single agents. Mentha x piperita, known worldwide as "Mentha of Pancalieri", is produced locally at Pancalieri (Turin, Italy). The EO from this Mentha species is considered as one of the best mint EOs in the world. In our research, we assessed the antifungal activity of "Mentha of Pancalieri" EO, either alone or in combination with azole drugs (fluconazole, itraconazole, ketoconazole) against a wide panel of yeast and dermatophyte clinical isolates. The EO was analyzed by GC-MS, and its antifungal properties were evaluated by minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) parameters, in accordance with the CLSI guidelines, with some modifications. The interaction of EO with azoles was evaluated through the chequerboard and isobologram methods. The results suggest that this EO exerts a fungicidal activity against yeasts and a fungistatic activity against dermatophytes. Interaction studies with azoles indicated mainly synergistic profiles between itraconazole and EO vs. Candida spp., Cryptococcus neoformans, and Trichophyton mentagrophytes. Thus, the "Mentha of Pancalieri" EO may act as a potential antifungal agent and could serve as a natural adjuvant for fungal infection treatment.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Mentha piperita/química , Monoterpenos/farmacologia , Óleos Voláteis/química , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Arthrodermataceae/efeitos dos fármacos , Arthrodermataceae/crescimento & desenvolvimento , Arthrodermataceae/isolamento & purificação , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Cryptococcus/efeitos dos fármacos , Cryptococcus/crescimento & desenvolvimento , Cryptococcus/isolamento & purificação , Combinação de Medicamentos , Sinergismo Farmacológico , Fluconazol/farmacologia , Guias como Assunto , Humanos , Itraconazol/farmacologia , Cetoconazol/farmacologia , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/isolamento & purificação , Óleos Voláteis/isolamento & purificação
6.
Ann Clin Lab Sci ; 49(4): 546-549, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31471347

RESUMO

Candida auris is an emerging pathogenic yeast responsible for nosocomial infections with high mortality, on a global scale. A 65-year-old woman with hypovolemic shock and severe metabolic acidosis was intubated and admitted to the intensive care unit (ICU). Shortly after admission, she developed ventilator-associated pneumonia caused by multidrug-resistant Acinetobacter baumannii, which necessitated treatment with high-dose ampicillin-sulbactam. Two weeks later, a yeast was cultured from her blood. It formed pale pink colonies on CHROMagar Candida medium and produced predominantly oval budding yeast cells with the occasional rudimentary pseudohyphae on cornmeal agar. ID 32 C identified the yeast as Candida sake However, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and sequencing of the D1/D2 region of the 28S rRNA gene identified the yeast as C. auris.


Assuntos
Candida/isolamento & purificação , Kit de Reagentes para Diagnóstico , Idoso , Antifúngicos/farmacologia , Candida/citologia , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Feminino , Humanos , Testes de Sensibilidade Microbiana
7.
Int. microbiol ; 22(3): 343-353, sept. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184841

RESUMO

The objective of the present study was to isolate Actinobacteria, preferably Streptomyces spp. from the rhizosphere soils of three ethno-medicinal plants collected in Serbia (Papaver rhoeas, Matricaria chamomilla, and Urtica dioica) and to screen their antifungal activity against Candida spp. Overall, 103 sporulating isolates were collected from rhizosphere soil samples and determined as Streptomyces spp. Two different media and two extraction procedures were used to facilitate identification of antifungals. Overall, 412 crude cell extracts were tested against Candida albicans using disk diffusion assays, with 42% (43/103) of the strains showing the ability to produce antifungal agents. Also, extracts inhibited growth of important human pathogens: Candida krusei, Candida parapsilosis, and Candida glabrata. Based on the established degree and range of antifungal activity, nine isolates, confirmed as streptomycetes by 16S rRNA sequencing, were selected for further testing. Their ability to inhibit Candida growth in liquid culture, to inhibit biofilm formation, and to disperse pre-formed biofilms was assessed with active concentrations from 8 to 250 μg/mL. High-performance liquid chromatographic profiles of extracts derived from selected strains were recorded, revealing moderate metabolic diversity. Our results proved that rhizosphere soil of ethno-medicinal plants is a prolific source of streptomycetes, producers of potentially new antifungal compounds


No disponible


Assuntos
Antifúngicos/metabolismo , Candida/efeitos dos fármacos , Rizosfera , Microbiologia do Solo , Streptomyces/isolamento & purificação , Candida/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Sérvia , Streptomyces/classificação , Streptomyces/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética
8.
J Basic Microbiol ; 59(8): 792-806, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31368594

RESUMO

The aim of this study was to examine four strains of two yeast species in relation to their capability for assimilating alkanes in the presence of heavy metals (HMs). The four strains tested were Candida pseudoglaebosa ENCB-7 and Kodamaea ohmeri ENCB-8R, ENCB-23, and ENCB-VIK. Determination was made of the expression of CYP52 genes involved in alkane hydroxylation. When exposed to Cu2+ , Zn2+ , Pb2+ , Cd2+ , and As3+ at pH 3 and 5, all four strains could assimilate several n-alkanes having at least six carbon atoms. The three K. ohmeri strains could also utilize branched alkanes, cycloalkanes, and n-octanol as sole carbon sources. Kinetic assays demonstrated greater biomass production and specific growth of the yeasts exposed to long-chain n-alkanes. Fragments of paralogous CYP52 genes of C. pseudoglaebosa ENCB-7 and K. ohmeri ENCB-23 were amplified, sequenced, and phylogenetically evaluated. Reverse-transcription polymerase chain reaction revealed that n-nonane and n-decane induced to CpCYP52-G3, CpCYP52-G9, and CpCYP52-G10. KoCYP52-G3 was induced with n-decane and n-octanol. Also, CpCYP52-G3 and CpCYP52-G9 were induced by glucose. In conclusion, C. pseudoglaebosa and K. ohmeri were able to degrade several alkanes in the presence of HMs and under acidic conditions. These yeasts harbor paralogous alkane-induced CYP52 genes, which display different profiles of transcriptional expression.


Assuntos
Alcanos/metabolismo , Metais Pesados/metabolismo , Saccharomycetales/metabolismo , Alcanos/química , Biodegradação Ambiental , Biomassa , Candida/classificação , Candida/genética , Candida/crescimento & desenvolvimento , Candida/metabolismo , Sistema Enzimático do Citocromo P-450/genética , DNA Ribossômico/genética , Proteínas Fúngicas/genética , Concentração de Íons de Hidrogênio , Cinética , Filogenia , Saccharomycetales/classificação , Saccharomycetales/genética , Saccharomycetales/crescimento & desenvolvimento
9.
J Mycol Med ; 29(3): 253-259, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31399349

RESUMO

The search for new antifungal strategies to overcome Candida infections is essential and a matter of public health, due to the high mortality associated to candidiasis, the increasing incidence of resistance to antifungals and the limited number of drugs available for treatment. Several approaches have been exploited in order to develop new antifungal strategies, e.g. the use of natural products, vaccines, and the combination of an antifungal drug to a non-antifungal substance. Nonetheless, issues related to pharmacokinetic parameters, toxicity and costs have been jeopardizing the discovery of new antifungal drugs. An alternative that could overcome these problems would be treating candidiasis with drugs that have been originally developed to treat other diseases. This strategy, known as drug repositioning or drug repurposing, could diminish the incidence of adverse effects and lower the cost of production, since several steps involved in drug discovery and development have already been accomplished. This review presents a set of known drugs that have been exploited as anticandidal agents, such as antidepressant agents, antiepileptic drugs, statins, among others. These substances affect the growth of Candida spp. in vitro, as well as virulence factors such as morphogenesis and biofilm formation. Moreover, some drugs are able to potentiate the anticandidal activity of known antifungal drugs. Drug repositioning appears as a remarkable alternative to increase the pharmacological arsenal against candidiasis, but further studies must be conducted in order to evaluate the real applicability of known drugs in the treatment of these infections.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Descoberta de Drogas , Reposicionamento de Medicamentos , Animais , Antidepressivos/uso terapêutico , Antifúngicos/efeitos adversos , Biofilmes/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Farmacorresistência Fúngica Múltipla , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana
10.
J Biotechnol ; 304: 89-96, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31449823

RESUMO

The effect of sodium selenite on batch culture of Candida utilis CCTCC M 209298 was investigated. Cell growth was inhibited while glutathione biosynthesis and secretion were improved during selenium enrichment. To reveal the mechanism underlying the decrease in biomass and the increase in glutathione, both metabolic flux analysis of key intermediates involved in glutathione metabolic pathway and transcriptome analysis of C. utilis by RNA-seq were carried out for selenized cells and the control without selenium enrichment. Results indicated that sodium selenite decreased carbon fluxes towards biomass but increased fluxes towards amino acids for the biosynthesis of glutathione and related amino acids. Selenium enrichment down-regulated a large number of genes involved in cell components and the cell cycle, resulting in decreased biomass as well as increased cell permeability. Moreover, several genes associated with transportation, binding, and mitochondrial and ribosomal functions for energy metabolism and protein synthesis were up-regulated in the presence of sodium selenite. All of these results disclosed the physiological response of C. utilis to sodium selenite.


Assuntos
Candida/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Glutationa/biossíntese , Selenito de Sódio/farmacologia , Aminoácidos/metabolismo , Técnicas de Cultura Celular por Lotes , Biomassa , Vias Biossintéticas , Candida/efeitos dos fármacos , Candida/metabolismo , Metabolismo Energético , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Análise de Sequência de RNA/métodos
11.
J Mycol Med ; 29(3): 201-209, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31378442

RESUMO

Candida albicans is a polymorphic opportunistic commensal that causes both superficial and systemic fungal infections especially in immunocompromised patients. Biologically synthesized silver nanoparticles (AgNPs) have emerged as potential antifungal agents. The present work evaluates the antifungal activity of Artemisia annua synthesized AgNPs against three Candida species (C. albicans ATCC 90028, C. tropicalis ATCC 750 and C. glabrata ATCC 90030). The in vitro effect of AgNPs was investigated for fungal growth, sterol content, secretion of hydrolytic enzymes and yeast-to-hyphal transition. The green synthesized AgNPs were effective against all the three species with minimum inhibitory concentration (MIC) in the range 80-120µgml-1. Candida glabrata showed greater sensitivity for AgNPs followed by Candida tropicalis and C. albicans. AgNPs at 4MIC were as effective as fluconazole (FLC) and caused only 5% haemolysis while FLC caused 50% haemolysis at the same concentration. The secretion of hydrolytic enzymes was the lowest in case of AgNP exposed C. glabrata. Yeast-to-hyphal transition was significantly reduced in treated C. albicans cells and showed disfigured morphology in SEM images. The decrease in ergosterol content was slightly higher (94%) in both C. glabrata and C. tropicalis in comparison to C. albicans (69%). Green synthesized AgNPs thus have immense potential as an antifungal and can play a crucial role in the management of Candida infections especially those caused by C. glabrata.


Assuntos
Antifúngicos/farmacologia , Artemisia annua/química , Candida/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/farmacologia , Candida/enzimologia , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida glabrata/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Fosfolipases/metabolismo
12.
J Appl Microbiol ; 127(5): 1362-1372, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31297951

RESUMO

AIM: The increase in the number of fungal infections worldwide, coupled with the limitations of current antifungal chemotherapy, demand the development of safe and effective new antifungals. Here, we presented the synthesis of a novel acridone (M14) and its antifungal properties against Candida and dermatophytes species. METHODS AND RESULTS: A series of 17 acridones was designed, synthesized and tested for its antifungal activity. The minimum inhibitory concentration (MIC) was determined by the broth microdilution method. Only the acridone M14 showed growth-inhibitory activity against reference strains and clinical isolates of Candida and dermatophytes, with MIC range of 7·81-31·25 µg ml-1 . Moreover, M14 exhibited fungicidal activity and prevented biofilm formation by C. albicans as well as reduced the viability of preformed biofilms, even at sub-MICs. The confocal laser scanning microscopy analysis revealed that C. albicans hyphal growth was completely inhibited in the presence of M14. Similarly, there was a severe inhibition on hyphal growth of Trichophyton rubrum. We also found that M14 has relatively low toxicity to human fibroblasts. CONCLUSIONS: The new acridone M14 has antifungal properties against Candida spp. and dermatophytes, and antibiofilm activity against C. albicans. In addition, M14 is relatively selective to fungal cells compared to human normal cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Because of its in vitro antifungal activity, anti-Candida biofilm effect and moderate cytotoxicity towards normal human cell, M14 may serve as a valuable lead compound to develop a new antifungal agent.


Assuntos
Acridonas/farmacologia , Antifúngicos/farmacologia , Arthrodermataceae/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Acridonas/síntese química , Antifúngicos/síntese química , Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Sobrevivência Celular , Humanos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Trichophyton/efeitos dos fármacos , Trichophyton/crescimento & desenvolvimento
13.
Oral Dis ; 25(7): 1798-1808, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31257663

RESUMO

OBJECTIVES: To evaluate (a) oral colonization of Candida species, especially for non-albicans Candida species (NACS), in xerostomic postradiotherapy head and neck cancer patients and (b) risk factors affecting their colonization. MATERIALS AND METHODS: Subjective and objective dry mouth scores, stimulated salivary flow rates, pH and buffering capacity were measured in 72 xerostomic postradiotherapy head and neck cancer patients. Candida counts and species identification were performed using oral rinse samples cultured in Candida Chromagar, followed by polymerase chain reaction and API 20C AUX system. RESULTS: Candida colonization was observed in 87.5% of subjects, with 80.6% and 48.6% of study population colonized by C. albicans and NACS, respectively. NACS was associated with high objective dry mouth scores, denture use, and females (p = .006, .009, and .036, respectively). In addition, Candida glabrata was detected more in females (p = .018) and denture wearers (p = .026), while Candida tropicalis was associated with high objective dry mouth scores (p = .022) and females (p = .027). Quantity of Candida colonization correlated positively with objective dry mouth scores (r = 0.599, p < .001) and negatively with salivary flow rates (r = -0.258, p = .041) and pH (r = -0.290, p = .022). CONCLUSION: NACS colonization was common in xerostomic head and neck cancer patients. Increased signs of dry mouth, female and dental prostheses may promote NACS colonization.


Assuntos
Candida/efeitos da radiação , Candidíase Bucal/epidemiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Boca/efeitos da radiação , Saliva/efeitos da radiação , Xerostomia/radioterapia , Adulto , Idoso , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candidíase Bucal/diagnóstico , Contagem de Colônia Microbiana , Feminino , Humanos , Pessoa de Meia-Idade , Boca/microbiologia , Saliva/metabolismo , Saliva/microbiologia , Glândulas Salivares/efeitos da radiação , Taxa Secretória/efeitos da radiação , Xerostomia/etiologia
14.
Int J Nanomedicine ; 14: 4667-4679, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308652

RESUMO

Purpose: The pathogenicity in Candida spp was attributed by several virulence factors such as production of tissue damaging extracellular enzymes, germ tube formation, hyphal morphogenesis and establishment of drug resistant biofilm. The objective of present study was to investigate the effects of silver nanoparticles (AgNPs) on growth, cell morphology and key virulence attributes of Candida species. Methods: AgNPs were synthesized by the using seed extract of Syzygium cumini (Sc), and were characterized by UV-Vis spectrophotometer, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM). ScAgNPs were used to evaluate their antifungal and antibacterial activity as well as their potent inhibitory effects on germ tube and biofilm formation and extracellular enzymes viz. phospholipases, proteinases, lipases and hemolysin secreted by Candida spp. Results: The MICs values of ScAgNPs were ranged from 0.125-0.250 mg/ml, whereas the MBCs and MFCs were 0.250 and 0.500 mg/ml, respectively. ScAgNPs significantly inhibit the production of phospholipases by 82.2, 75.7, 78.7, 62.5, and 65.8%; proteinases by 82.0, 72.0, 77.5, 67.0, and 83.7%; lipase by 69.4, 58.8, 60.0, 42.9, and 65.0%; and hemolysin by 62.8, 69.7, 67.2, 73.1, and 70.2% in C. albicans, C. tropicalis, C. dubliniensis, C. parapsilosis and C. krusei, respectively, at 500 µg/ml. ScAgNPs inhibit germ tube formation in C. albicans up to 97.1% at 0.25 mg/ml. LIVE/DEAD staining results showed that ScAgNPs almost completely inhibit biofilm formation in C. albicans. TEM analysis shows that ScAgNPs not only anchored onto the cell surface but also penetrated and accumulated in the cytoplasm that causes severe damage to the cell wall and cytoplasmic membrane. Conclusion: To summarize, the biosynthesized ScAgNPs strongly suppressed the multiplication, germ tube and biofilm formation and most importantly secretion of hydrolytic enzymes (viz. phospholipases, proteinases, lipases and hemolysin) by Candia spp. The present research work open several avenues of further study, such as to explore the molecular mechanism of inhibition of germ tubes and biofilm formation and suppression of production of various hydrolytic enzymes by Candida spp.


Assuntos
Antifúngicos/farmacologia , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Nanopartículas Metálicas/química , Prata/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida/citologia , Candida/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Proteínas Hemolisinas/metabolismo , Humanos , Hidrólise , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Syzygium/química , Virulência/efeitos dos fármacos , Fatores de Virulência
15.
Biomed Res Int ; 2019: 8051270, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360725

RESUMO

Aims: Microbial colonization of silicone voice prostheses by bacteria and Candida species limits the device lifetime of modern voice prostheses in laryngectomized patients. Thus, research focuses on biofilm inhibitive properties of novel materials, coatings, and surface enhancements. Goal of this in vitro study was the evaluation of seven commonly used growth media to simulate growth of mixed oropharyngeal species as mesoscale biofilms on prosthetic silicone for future research purposes. Methods and Results: Yeast Peptone Dextrose medium (YPD), Yeast Nitrogen Base medium (YNB), M199 medium, Spider medium, RPMI 1640 medium, Tryptic Soy Broth (TSB), and Fetal Bovine Serum (FBS) were used to culture combined mixed Candida strains and mixed bacterial-fungal compositions on silicone over the period of 22 days. The biofilm surface spread and the microscopic growth showed variations from in vivo biofilms depending on the microbial composition and growth medium. Conclusion: YPD and FBS prove to support continuous in vitro growth of mixed bacterial-fungal oropharyngeal biofilms deposits over weeks as needed for longterm in vitro testing with oropharyngeal biofilm compositions. Significance and Impact of Study: The study provides data on culture conditions for mixed multispecies biofilm compositions that can be used for future prosthesis designs.


Assuntos
Candida/crescimento & desenvolvimento , Meios de Cultura/farmacologia , Laringe Artificial/microbiologia , Orofaringe/microbiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida/patogenicidade , Meios de Cultura/química , Humanos , Laringectomia , Orofaringe/efeitos dos fármacos , Silicones/química , Silicones/uso terapêutico
16.
Int J Mol Sci ; 20(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340425

RESUMO

The aim of this study was to perform a systematic review of the literature followed by a meta-analysis about the efficacy of photodynamic therapy (PDT) on the microorganisms responsible for dental caries. The research question and the keywords were constructed according to the PICO strategy. The article search was done in Embase, Lilacs, Scielo, Medline, Scopus, Cochrane Library, Web of Science, Science Direct, and Pubmed databases. Randomized clinical trials and in vitro studies were selected in the review. The study was conducted according the PRISMA guideline for systematic review. A total of 34 articles were included in the qualitative analysis and four articles were divided into two subgroups to perform the meta-analysis. Few studies have achieved an effective microbial reduction in microorganisms associated with the pathogenesis of dental caries. The results highlight that there is no consensus about the study protocols for PDT against cariogenic microorganisms, although the results showed the PDT could be a good alternative for the treatment of dental caries.


Assuntos
Infecções por Bacteroidaceae/tratamento farmacológico , Candidíase/tratamento farmacológico , Cárie Dentária/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções por Bacteroidaceae/microbiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Candidíase/microbiologia , Curcumina/farmacologia , Cárie Dentária/microbiologia , Humanos , Azul de Metileno/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/patogenicidade , Corantes de Rosanilina/farmacologia , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Streptococcus/crescimento & desenvolvimento , Streptococcus/patogenicidade , Cloreto de Tolônio/farmacologia , Resultado do Tratamento
17.
Mater Sci Eng C Mater Biol Appl ; 103: 109830, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349502

RESUMO

Among several bioactive peptides identified from the venom glands of the Tityus stigmurus scorpion, one peptide with hypotensive action (TistH, Tityus stigmurus Hypotensin) showed multifunctional and biotechnological applications. The maximum efficacy of this class of compounds can be achieved by immobilizing it in specific and suitable biomaterials or suitable carriers. In this study, distinct entrapment methods of TistH in chitosan nanoparticles was tested using its incorporation (CN-TistH-Inc) or adsorption (CN-TistH-Ads) methods by ionotropic gelification. Physico-chemical properties as well as biocompatibility and antifungal efficacy were assessed for different samples. Atomic force microscopy and field emission gun scanning electronic microscopy images associated with particle size measurements demonstrated that the two methods induced cationic spherical, small (< 160 nm), and narrow-sized (PdI about 0.3) nanoparticles, even after peptide loading greater than 96.5%, which was confirmed using Fourier transform infrared spectroscopy. The colloidal suspensions showed to be stable for 8 weeks and were able to induce the desired slow in vitro peptide release. Cytotoxicity assays performed in normal cells originated from murine macrophages (RAW 264.7) and kidneys of African green monkeys (Vero E6) suggested biocompatibility of samples. The CN-TistH-Inc and CN-TistH-Ads showed a minimal inhibitory concentration of 89.2 µg.mL-1 against Candida albicans, 11.1 µg.mL-1 for C. parapsilosis and C. tropicalis, confirmed by minimum fungicidal concentrations assay. Moreover, the TistH-loaded cross-linked chitosan nanoparticles significantly reduced the biofilm formation of clinical yeast sepsis of C. tropicalis and C. krusei, as well as clinical yeasts of vulvovaginal candidiasis of C. albicans. In this approach, biodegradable nanocarriers prepared using simple and reproducible methods demonstrated the ability to deliver the TistH peptide from T. stigmurus and improve its antifungal efficacy.


Assuntos
Antifúngicos , Proteínas de Artrópodes , Candida/crescimento & desenvolvimento , Quitosana , Nanopartículas/química , Peptídeos , Venenos de Escorpião/química , Escorpiões/química , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Proteínas de Artrópodes/química , Proteínas de Artrópodes/farmacologia , Quitosana/química , Quitosana/farmacologia , Camundongos , Peptídeos/química , Peptídeos/farmacologia , Células RAW 264.7 , Células Vero
18.
Mycopathologia ; 184(3): 403-411, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31187338

RESUMO

BACKGROUND: The predominance of non-Candida albicans Candida (NCAC) species causing healthcare-associated infections has increased over the last decade pertaining to their ability to form biofilms on medical devices. These biofilm-associated infections are challenging to treat as they are resistant to antifungal agents and evade host-immune response resulting in a high risk of device failure or biomaterial removal. Thus, to minimize the risk of biofilm-associated infections, preventing biofilm formation is the best approach which is mediated by the quorum quenching process. METHODS: The present study investigated the modulatory effect of 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) on NCAC biofilm formation and also assessed the effect of the DMHF-coated catheters on biofilm formation of NCAC. The NCAC isolates studied were Candida tropicalis, Candida glabrata and Candida krusei isolated from catheter tip, urine and blood, respectively. RESULTS: DMHF at a concentration of 30 µg/mL showed an inhibitory effect against NCAC biofilms at various stages and was statistically significant (p ≤ 0.05) against the various concentrations (50-5 µg/mL) tested and also among the three phases of experiment. The furanone content on coated catheters ranged from 170 to 750 µg and release of furanone from the coated catheter was about 15 µg for 30 days. The effect of DMHF-coated catheters on NCAC biofilm formation was observed by the scanning electron microscopy which revealed the absence of NCAC adherence on DMHF-coated catheters. DISCUSSION: This study provides a design to develop furanone-coated biomaterials which could be implemented in healthcare settings to reduce medical device-associated infections. The excellent biological performance, combined with their antimicrobial properties, suggests that 2,5-dimethyl-4-hydroxy-3(2H)-furanone could be an effective anti-infective coating for implantable devices.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Furanos/farmacologia , Biofilmes/crescimento & desenvolvimento , Sangue/microbiologia , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candidíase/microbiologia , Cateteres/microbiologia , Microbiologia Ambiental , Humanos , Urina/microbiologia
19.
Infez Med ; 27(2): 159-167, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31205039

RESUMO

Invasive candidiasis is an important cause of morbidity and mortality, which primarily occurs in intensive care units. The Candida colonization index is an accepted score as an early warning tool for invasive candidiasis. This study was performed in a medical PICU with patients prone to contracting invasive candidiasis, to determine the usefulness of the Candida colonization index in forecasting invasive candidiasis in children. This prospective study including 87 patients (children 1 month to 16 years old with several illnesses and requiring ICU care) was conducted in a 22-bed medical PICU, Health Science University of Kayseri Training and Research Hospital, between January 2015 and September 2016. Those patients not on antifungal therapy, who were expected to stay more than seven days in PICU and had no history of a PICU stay within the previous two months were included in the study. In all patients, rectal, cervical, throat, axillary, perineal and nasal swab cultures, urine culture and blood culture tests were performed at admission and every week throughout their stay. Overall, 2639 swab and urine cultures (mean: 30.3) and 325 blood cultures (mean: 3.73) were obtained from 87 patients and a total of 576 grew Candida spp. In patients' swab and urine cultures C. albicans was detected in 64.5%, C. parapsilosis in 12.1%, C. glabrata in 7.5%, Saccharomyces spp in 3.0 %, C. tropicalis in 2.4%, C. krusei in 2.1% and C. kefyr in 1.2%. Three patients had C. albicans and one had C. parapsilosis growth in blood culture. Sensitivity, specificity, positive predictive value and negative predictive value for CI were found to be 33.73%, 100%, 6.7%, and 100%, respectively. Patients are at risk of fungal infection in paediatric intensive care units. Specificity and the negative predictive value of 100 % indicate that CI is a useful score to rule out the presence of invasive fungal disease. On the other hand, the low rate of sensitivity (33.3 %) and positive predictive value (6,7%) make this score less reliable in forecasting invasive candidiasis in children.


Assuntos
Candida/isolamento & purificação , Candidemia/microbiologia , Unidades de Terapia Intensiva Pediátrica , Adolescente , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Caspofungina/uso terapêutico , Criança , Pré-Escolar , Suscetibilidade a Doenças , Estudos de Viabilidade , Feminino , Fluconazol/uso terapêutico , Humanos , Lactente , Itraconazol/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Especificidade de Órgãos , Estudos Prospectivos , Sensibilidade e Especificidade , Voriconazol/uso terapêutico
20.
Biomed Res Int ; 2019: 3941242, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31179320

RESUMO

The microbial resistance of fungi and bacteria is currently considered a major public health problem. Esters derived from cinnamic acid have a broad spectrum of pharmacological properties that include antimicrobial activity. In this study, a collection of structurally related 4-chlorocinnamic acid esters was prepared using Fischer esterification reactions, alkyl or aryl halide esterification, and Mitsunobu and Steglich reactions. All of the esters were submitted to antimicrobial tests against strains of the species Candida albicans, Candida glabrata, Candida krusei, Candida guilliermondii, Pseudomonas aeruginosa, and Staphylococcus aureus. The compounds also were subjected to molecular docking study with the enzyme 14α-demethylase. Twelve esters derived from 4-chlorocinnamic acid were obtained, with yields varying from 26.3% to 97.6%, three of which were unpublished. The ester methyl 4-chlorocinnamate (1) presented activity against S. aureus at the highest concentration tested. In the antifungal evaluation, all of the esters were bioactive, but methoxyethyl 4-chlorocinnamate (4) and perillyl 4-chlorocinnamate (11) were the most potent (MIC = 0.13 and 0.024 µmol/mL, respectively). The data of molecular docking suggested that all the compounds present good affinity towards the active site related to antifungal activity. Therefore, the esters tested may be inhibitors of the enzyme 14α-demethylase. In addition, the results demonstrate that substituents of short alkyl chains with presence of heteroatom, such as oxygen, or those with a perillyl type terpenic substructure promote better antifungal profiles.


Assuntos
Anti-Infecciosos , Candida/crescimento & desenvolvimento , Cinamatos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cinamatos/química , Cinamatos/farmacologia
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