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1.
Emerg Infect Dis ; 30(13): S36-S40, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38561642

RESUMO

Candida auris is an emerging fungal pathogen that typically affects patients in healthcare settings. Data on C. auris cases in correctional facilities are limited but are needed to guide public health recommendations. We describe cases and challenges of providing care for 13 patients who were transferred to correctional facilities during January 2020-December 2022 after having a positive C. auris specimen. All patients had positive specimens identified while receiving inpatient care at healthcare facilities in geographic areas with high C. auris prevalence. Correctional facilities reported challenges managing patients and implementing prevention measures; those challenges varied by whether patients were housed in prison medical units or general population units. Although rarely reported, C. auris cases in persons who are incarcerated may occur, particularly in persons with known risk factors. Measures to manage cases and prevent C. auris spread in correctional facilities should address setting-specific challenges in healthcare and nonhealthcare correctional environments.


Assuntos
Candida , Candidíase , Humanos , Candidíase/microbiologia , Candida auris , Antifúngicos/uso terapêutico , Estabelecimentos Correcionais
2.
Mycopathologia ; 189(3): 35, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637433

RESUMO

Candida auris, an emerging and multidrug-resistant fungal pathogen, has led to numerous outbreaks in China. While the resistance mechanisms against azole and amphotericin B have been studied, the development of drug resistance in this pathogen remains poorly understood, particularly in in vivo-generated drug-resistant strains. This study employed pathogen whole-genome sequencing to investigate the epidemiology and drug-resistance mutations of C. auris using 16 strains isolated from two patients. Identification was conducted through Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antimicrobial susceptibilities were assessed using broth microdilution and Sensititre YeastOne YO10. Whole-genome sequencing revealed that all isolates belonged to the South Asian lineage, displaying genetic heterogeneity. Despite low genetic variability among patient isolates, notable mutations were identified, including Y132F in ERG11 and A585S in TAC1b, likely linked to increased fluconazole resistance. Strains from patient B also carried F214L in TAC1b, resulting in a consistent voriconazole minimum inhibitory concentration of 4 µg/mL across all isolates. Furthermore, a novel frameshift mutation in the SNG1 gene was observed in amphotericin B-resistant isolates compared to susceptible ones. Our findings suggest the potential transmission of C. auris and emphasize the need to explore variations related to antifungal resistance. This involves analyzing genomic mutations and karyotypes, especially in vivo, to compare sensitive and resistant strains. Further monitoring and validation efforts are crucial for a comprehensive understanding of the mechanisms of drug resistance in C. auris.


Assuntos
Antifúngicos , Candidíase , Humanos , Antifúngicos/farmacologia , Candidíase/microbiologia , Candida auris , Candida , Anfotericina B/farmacologia , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana
3.
Microb Genom ; 10(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38630608

RESUMO

Fungal pathogens commonly originate from benign or non-pathogenic strains living in the natural environment. The recently emerged human pathogen, Candida auris, is one example of a fungus believed to have originated in the environment and recently transitioned into a clinical setting. To date, however, there is limited evidence about the origins of this species in the natural environment and when it began associating with humans. One approach to overcome this gap is to reconstruct phylogenetic relationships between (1) strains isolated from clinical and non-clinical environments and (2) between species known to cause disease in humans and benign environmental saprobes. C. auris belongs to the Candida/Clavispora clade, a diverse group of 45 yeast species including human pathogens and environmental saprobes. We present a phylogenomic analysis of the Candida/Clavispora clade aimed at understanding the ecological breadth and evolutionary relationships between an expanded sample of environmentally and clinically isolated yeasts. To build a robust framework for investigating these relationships, we developed a whole-genome sequence dataset of 108 isolates representing 18 species, including four newly sequenced species and 18 environmentally isolated strains. Our phylogeny, based on 619 orthologous genes, shows environmentally isolated species and strains interspersed with clinically isolated counterparts, suggesting that there have been many transitions between humans and the natural environment in this clade. Our findings highlight the breadth of environments these yeasts inhabit and imply that many clinically isolated yeasts in this clade could just as easily live outside the human body in diverse natural environments and vice versa.


Assuntos
Candida auris , Candidíase , Humanos , Filogenia , Candidíase/microbiologia , Candida/genética , Evolução Biológica
4.
Clin Lab ; 70(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623664

RESUMO

BACKGROUND: Despite the advanced laboratory technologies available today, blood culture is the gold standard method in the diagnosis of bloodstream infections. Automated blood culture devices give blood culture results for laboratories approximately in 2 - 3 days up to 7 days. Moreover, some microorganisms like nonreproducible bacteria, fungi or viruses cannot be produced in culture. Among all samples taken for blood culture on suspicion of infection approximately 10% are determined as positive whereas the false positive rate due to contamination is 5%. Especially in life-threatening severe conditions such as sepsis early diagnosis and prompt treatment are crucial. Based on this the aim of this study is to investigate complete blood count parameters as potential early markers in Escherichia coli, Staphylococcus aureus and Candida albicans bloodstream infections using an ex vivo whole blood model. METHODS: Blood samples collected from healthy donors (n = 10) were treated with suspensions containing a certain concentration of microorganisms (107 CFU/mL for both E. coli ATCC 25922 and S. aureus ATCC 29213, 106 CFU/mL for C. albicans ATCC 14053). After bacteremia and candidemia were induced, complete blood count parameters were analyzed hourly in the samples until the end of the 4th hour with a Mindray BC-6800 hematology analyzer. Statistical analysis was performed by Tukey-Kramer post-hoc multiple comparison test and statistical significance was accepted as p < 0.05. RESULTS: When platelet derived parameter baseline values were compared to hourly values in E. coli and S. aureus induced whole blood samples, it was found that the decrease in PLT, P-LCC and the increase in IPF% was significant from the first hour whereas the increase in IMG% was found to be significant only from the 3rd hour onward. In the experiments with C. albicans, it was observed that the increase in IPF% and IMG% was significant from the 2nd and 3rd hour onward, respectively. There was no relationship between MPV, P-LCR, and NLR baseline and hourly results in any microorganism induced model. CONCLUSIONS: IPF% can guide clinicians in the early diagnosis and management of treatment of infections caused by S. aureus, E. coli, and C. albicans.


Assuntos
Candidemia , Candidíase , Humanos , Escherichia coli , Staphylococcus aureus , Candida albicans , Candidíase/diagnóstico , Candidíase/microbiologia , Candidemia/microbiologia , Contagem de Células Sanguíneas
5.
Biomaterials ; 307: 122525, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489910

RESUMO

Candida albicans is a commensal yeast of the human intestinal microbiota that, under predisposing conditions, can become pathogenic and cause life-threatening systemic infections (candidiasis). Fungal-host interactions during candidiasis are commonly studied using conventional 2D in vitro models, which have provided critical insights into the pathogenicity. However, microphysiological models with a higher biological complexity may be more suitable to mimic in vivo-like infection processes and antifungal drug efficacy. Therefore, a 3D intestine-on-chip model was used to investigate fungal-host interactions during the onset of invasive candidiasis and evaluate antifungal treatment under clinically relevant conditions. By combining microbiological and image-based analyses we quantified infection processes such as invasiveness and fungal translocation across the epithelial barrier. Additionally, we obtained novel insights into fungal microcolony morphology and association with the tissue. Our results demonstrate that C. albicans microcolonies induce injury to the epithelial tissue by disrupting apical cell-cell contacts and causing inflammation. Caspofungin treatment effectively reduced the fungal biomass and induced substantial alterations in microcolony morphology during infection with a wild-type strain. However, caspofungin showed limited effects after infection with an echinocandin-resistant clinical isolate. Collectively, this organ-on-chip model can be leveraged for in-depth characterization of pathogen-host interactions and alterations due to antimicrobial treatment.


Assuntos
Candida albicans , Candidíase , Humanos , Caspofungina/farmacologia , Caspofungina/uso terapêutico , Antifúngicos/farmacologia , Virulência , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Intestinos
6.
mBio ; 15(4): e0014624, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38477572

RESUMO

The emergence and evolutionary path of Candida auris poses an intriguing scientific enigma. Its isolation from a pet dog's oral cavity in Kansas, reported by White et al. (T. C. White, B. D. Esquivel, E. M. Rouse Salcido, A. M. Schweiker, et al., mBio 15:e03080-23, 2024, https://doi.org/10.1128/mbio.03080-23), carries significant implications. This discovery intensifies concerns about its hypothetical capacity for zoonotic transmission, particularly considering the dog's extensive human contact and the absence of secondary animal/human cases in both animals and humans. The findings challenge established notions of C. auris transmissibility and underscore the need for further investigation into the transmission dynamics, especially zooanthroponotic pathways. It raises concerns about its adaptability in different hosts and environments, highlighting potential role of environmental and animal reservoirs in its dissemination. Critical points include the evolving thermal tolerance and the genetic divergence in the isolate. This case exemplifies the necessity for an integrated One Health approach, combining human, animal, and environmental health perspectives, to unravel the complexities of C. auris's emergence and behavior.


Assuntos
Candida , Candidíase , Cães , Humanos , Animais , Candida/genética , Candida/isolamento & purificação , Candidíase/veterinária , Candidíase/microbiologia , Candida auris , Kansas , Mudança Climática , Fungos , Zoonoses , Boca
7.
Nat Commun ; 15(1): 2381, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493178

RESUMO

Candida auris has become a serious threat to public health. The mechanisms of how this fungal pathogen adapts to the mammalian host are poorly understood. Here we report the rapid evolution of an adaptive C. auris multicellular aggregative morphology in the murine host during systemic infection. C. auris aggregative cells accumulate in the brain and exhibit obvious advantages over the single-celled yeast-form cells during systemic infection. Genetic mutations, specifically de novo point mutations in genes associated with cell division or budding processes, underlie the rapid evolution of this aggregative phenotype. Most mutated C. auris genes are associated with the regulation of cell wall integrity, cytokinesis, cytoskeletal properties, and cellular polarization. Moreover, the multicellular aggregates are notably more recalcitrant to the host antimicrobial peptides LL-37 and PACAP relative to the single-celled yeast-form cells. Overall, to survive in the host, C. auris can rapidly evolve a multicellular aggregative morphology via genetic mutations.


Assuntos
Candidíase , Sepse , Animais , Camundongos , Candida/genética , Candidíase/microbiologia , Candida auris , Saccharomyces cerevisiae , Fenótipo , Antifúngicos , Testes de Sensibilidade Microbiana , Mamíferos
8.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474027

RESUMO

Candida spp. periprosthetic joint infections are rare but difficult-to-treat events, with a slow onset, unspecific symptoms or signs, and a significant relapse risk. Treatment with antifungals meets with little success, whereas prosthesis removal improves the outcome. In fact, Candida spp. adhere to orthopedic devices and grow forming biofilms that contribute to the persistence of this infection and relapse, and there is insufficient evidence that the use of antifungals has additional benefits for anti-biofilm activity. To date, studies on the direct antifungal activity of silver against Candida spp. are still scanty. Additionally, polycaprolactone (PCL), either pure or blended with calcium phosphate, could be a good candidate for the design of 3D scaffolds as engineered bone graft substitutes. Thus, the present research aimed to assess the antifungal and anti-biofilm activity of PCL-based constructs by the addition of antimicrobials, for instance, silver, against C. albicans and C. auris. The appearance of an inhibition halo around silver-functionalized PCL scaffolds for both C. albicans and C. auris was revealed, and a significant decrease in both adherent and planktonic yeasts further demonstrated the release of Ag+ from the 3D constructs. Due to the combined antifungal, osteoproliferative, and biodegradable properties, PCL-based 3D scaffolds enriched with silver showed good potential for bone tissue engineering and offer a promising strategy as an ideal anti-adhesive and anti-biofilm tool for the reduction in prosthetic joints of infections caused by Candida spp. by using antimicrobial molecule-targeted delivery.


Assuntos
Candida albicans , Candidíase , Poliésteres , Antifúngicos/farmacologia , Candida auris , Prata , Candida , Candidíase/microbiologia , Biofilmes , Fosfatos de Cálcio , Recidiva , Testes de Sensibilidade Microbiana
9.
J Mycol Med ; 34(1): 101466, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38382172

RESUMO

Data published on Panamanian fungal disease are scarce, mostly case reports. To date, there is no paper that compiles the burden of fungal disease Here we estimate for the first time the incidence and prevalence of fungal diseases in Panama. Data on fungal disease were obtained from different search engines: PubMed, Google Scholar, Scielo and Lilacs. For population and at risk diseases, we used statistics from worldometer, UNAIDS, and WHO. Incidence, prevalence, and absolute numbers were calculated based on the population at risk. Panamanian population in 2022 was 4,429,739. We estimated that 85,530 (1.93 %) people suffer from fungal diseases. The most frequent fungal infection was recurrent Candida vaginitis (3285/100,000). There are 31,000 HIV-infected people in Panama and based on the number of cases not receiving anti-retroviral therapy (14,570), and previous reports of prevalence of opportunistic infections, we estimated annual incidences of 4.0/100,000 for cryptococcal meningitis, 29.5/100,000 for oral candidiasis, 23.1/100,000 for esophageal candidiasis, 29.5/100,000 for Pneumocystis pneumonia, 15.1/100,000, and for histoplasmosis. For chronic pulmonary aspergillosis (CPA) and fungal asthma we used data from Guatemala and Colombia to estimate COPD and asthma prevalence and WHO report for tuberculosis. We estimated annual incidences of 6.1/100,000 for invasive aspergillosis and prevalence of 31.5/100,000 for CPA, 60.2/100,000 for allergic bronchopulmonary aspergillosis, and 79.5/100,000 for severe asthma with fungal sensitisation. Other incidence estimates were 5.0/100,000 for candidaemia, 0.20/100,000 for mucormycosis, and 4.97/100,000 for fungal keratitis. Even though this report on burden of fungal disease is a forward step, more epidemiological studies to validate these estimates are needed.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Aspergilose , Asma , Candidemia , Candidíase , Aspergilose Pulmonar , Feminino , Humanos , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/complicações , Aspergilose/microbiologia , Candidíase/microbiologia , Aspergilose Pulmonar/microbiologia , Asma/epidemiologia , Candidemia/epidemiologia , Incidência , Prevalência
10.
mBio ; 15(3): e0340923, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349176

RESUMO

Candida albicans can cause mucosal infections in humans. This includes oropharyngeal candidiasis, which is commonly observed in human immunodeficiency virus infected patients, and vulvovaginal candidiasis (VVC), which is the most frequent manifestation of candidiasis. Epithelial cell invasion by C. albicans hyphae is accompanied by the secretion of candidalysin, a peptide toxin that causes epithelial cell cytotoxicity. During vaginal infections, candidalysin-driven tissue damage triggers epithelial signaling pathways, leading to hyperinflammatory responses and immunopathology, a hallmark of VVC. Therefore, we proposed blocking candidalysin activity using nanobodies to reduce epithelial damage and inflammation as a therapeutic strategy for VVC. Anti-candidalysin nanobodies were confirmed to localize around epithelial-invading C. albicans hyphae, even within the invasion pocket where candidalysin is secreted. The nanobodies reduced candidalysin-induced damage to epithelial cells and downstream proinflammatory responses. Accordingly, the nanobodies also decreased neutrophil activation and recruitment. In silico mathematical modeling enabled the quantification of epithelial damage caused by candidalysin under various nanobody dosing strategies. Thus, nanobody-mediated neutralization of candidalysin offers a novel therapeutic approach to block immunopathogenic events during VVC and alleviate symptoms.IMPORTANCEWorldwide, vaginal infections caused by Candida albicans (VVC) annually affect millions of women, with symptoms significantly impacting quality of life. Current treatments are based on anti-fungals and probiotics that target the fungus. However, in some cases, infections are recurrent, called recurrent VVC, which often fails to respond to treatment. Vaginal mucosal tissue damage caused by the C. albicans peptide toxin candidalysin is a key driver in the induction of hyperinflammatory responses that fail to clear the infection and contribute to immunopathology and disease severity. In this pre-clinical evaluation, we show that nanobody-mediated candidalysin neutralization reduces tissue damage and thereby limits inflammation. Implementation of candidalysin-neutralizing nanobodies may prove an attractive strategy to alleviate symptoms in complicated VVC cases.


Assuntos
Candidíase Vulvovaginal , Candidíase , Proteínas Fúngicas , Anticorpos de Domínio Único , Humanos , Feminino , Candidíase Vulvovaginal/microbiologia , Qualidade de Vida , Anticorpos de Domínio Único/metabolismo , Candida albicans/metabolismo , Candidíase/microbiologia , Inflamação
11.
J Med Chem ; 67(5): 4007-4025, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38381075

RESUMO

Invasive fungal infections pose a serious threat to public health and are associated with high mortality and incidence rates. The development of novel antifungal agents is urgently needed. Based on hit-to-lead optimization, a series of 2,4,6-trisubstituted triazine hydrazone compounds were designed, synthesized, and biological evaluation was performed, leading to the identification of compound 28 with excellent in vitro synergy (FICI range: 0.094-0.38) and improved monotherapy potency against fluconazole-resistant Candida albicans and Candida auris (MIC range: 1.0-16.0 µg/mL). Moreover, 28 exhibited broad-spectrum antifungal activity against multiple pathogenic strains. Furthermore, 28 could inhibit hyphal and biofilm formation, which may be related to its ability to disrupt the fungal cell wall. Additionally, 28 significantly reduced the CFU in a mouse model of disseminated infection with candidiasis at a dose of 10 mg/kg. Overall, the triazine-based hydrazone compound 28 with low cytotoxicity, hemolysis, and favorable ADME/T characteristics represents a promising lead to further investigation.


Assuntos
Antifúngicos , Candidíase , Animais , Camundongos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Testes de Sensibilidade Microbiana , Fluconazol/farmacologia , Candida albicans , Candidíase/tratamento farmacológico , Candidíase/microbiologia
12.
Rev. esp. quimioter ; 37(1): 93-96, Feb. 2024. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-230427

RESUMO

Introduction. Non-albicans Candida species, such as Candida kefyr, are emerging pathogens. Chromogenic media are highly useful for the diagnosis of urinary tract infections (UTIs). The aim was to describe the behavior of this specie on a non-specific chromogenic medium. Material and methods. A retrospective study of cases of candiduria detected in the Microbiology laboratory of the Virgen de las Nieves Hospital in Granada (Spain) between 2016 and 2021 (N=2,130). Urine samples were quantitatively seeded on non-selective UriSelect™4 chromogenic agar. Results. Between 2016 and 2021, C. kefyr was the seventh most frequent Candida species responsible for candiduria in our setting (n=15). The macroscopic appearance of C. kefyr colonies, punctiform and bluish, allowed the direct identification of these microorganisms. Conclusions. This study provides the first description of the specific behavior of C. kefyr on UriSelect™4 agar, which differentiates it from other Candida species based on its enzymatic characteristics. (AU)


Introducción. Las especies de Candida no-albicans, como Candida kefyr, son patógenos emergentes. Los medios cromogénicos son muy útiles para el diagnóstico de infecciones del tracto urinario (ITU). El objetivo era describir el comportamiento de esta especie en un medio cromogénico no específico. Material y métodos. Estudio retrospectivo de casos de candiduria detectados en el laboratorio de Microbiología del Hospital Virgen de las Nieves de Granada (España) entre 2016 y 2021 (N=2.130). Las muestras de orina se sembraron cuantitativamente en agar cromogénico no selectivo Uri Select™4. Resultados. C. kefyr fue la séptima especie de Candida responsables de la candiduria en nuestro medio (n = 15). El aspecto macroscópico de las colonias de C. kefyr, puntiformes y azuladas, permitió su identificación presuntiva directamente. Conclusiones. Este estudio proporciona la primera descripción del comportamiento específico de C. kefyr en agar Uri Select™4, que lo diferencia de otras especies de Candida en función de sus características enzimáticas. (AU)


Assuntos
Humanos , Ágar , Candida , Candidíase/diagnóstico , Candidíase/microbiologia , Infecções Urinárias/microbiologia , Kluyveromyces , Estudos Retrospectivos
13.
Front Cell Infect Microbiol ; 14: 1339501, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404288

RESUMO

In the last twenty years, there has been a significant increase in invasive fungal infections, which has corresponded with the expanding population of individuals with compromised immune systems. As a result, the mortality rate linked to these infections remains unacceptably high. The currently available antifungal drugs, such as azoles, polyenes, and echinocandins, face limitations in terms of their diversity, the escalating resistance of fungi and the occurrence of significant adverse effects. Consequently, there is an urgent need to develop new antifungal medications. Vaccines and antibodies present a promising avenue for addressing fungal infections due to their targeted antifungal properties and ability to modulate the immune response. This review investigates the structure and function of cell wall proteins, secreted proteins, and functional proteins within C. albicans. Furthermore, it seeks to analyze the current advancements and challenges in macromolecular drugs to identify new targets for the effective management of candidiasis.


Assuntos
Antifúngicos , Candidíase , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Equinocandinas/farmacologia , Candida albicans , Farmacorresistência Fúngica , Imunoterapia
14.
mSphere ; 9(2): e0057723, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38299868

RESUMO

Since 2016, in Colombia, ongoing transmission of Candida auris has been reported in multiple cities. Here, we provide an updated description of C. auris genomic epidemiology and the dynamics of antifungal resistance in Colombia. We sequenced 99 isolates from C. auris cases with collection dates ranging from June 2016 to January 2021; the resulting sequences coupled with 103 previously generated sequences from C. auris cases were described in a phylogenetic analysis. All C. auris cases were clade IV. Of the 182 isolates with antifungal susceptibility data, 67 (37%) were resistant to fluconazole, and 39 (21%) were resistant to amphotericin B. Isolates predominately clustered by country except for 16 isolates from Bogotá, Colombia, which grouped with isolates from Venezuela. The largest cluster (N = 166 isolates) contained two subgroups. The first subgroup contained 26 isolates, mainly from César; of these, 85% (N = 22) were resistant to fluconazole. The second subgroup consisted of 47 isolates from the north coast; of these, 81% (N = 38) were resistant to amphotericin B. Mutations in the ERG11 and TAC1B genes were identified in fluconazole-resistant isolates. This work describes molecular mechanisms associated with C. auris antifungal resistance in Colombia. Overall, C. auris cases from different geographic locations in Colombia exhibited high genetic relatedness, suggesting continued transmission between cities since 2016. These findings also suggest a lack of or minimal introductions of different clades of C. auris into Colombia. IMPORTANCE: Candida auris is an emerging fungus that presents a serious global health threat and has caused multiple outbreaks in Colombia. This work discusses the likelihood of introductions and local transmission of C. auris and provides an updated description of the molecular mechanisms associated with antifungal resistance in Colombia. Efforts like this provide information about the evolving C. auris burden that could help guide public health strategies to control C. auris spread.


Assuntos
Antifúngicos , Candidíase , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Anfotericina B , Candida auris , Fluconazol , Colômbia/epidemiologia , Candida/genética , Candidíase/microbiologia , Filogenia , Genômica
15.
BMC Microbiol ; 24(1): 54, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341568

RESUMO

BACKGROUND: Candida albicans is the most common fungus that causes vaginal candidiasis in immunocompetent women and catastrophic infections in immunocompromised patients. The treatment of such infections is hindered due to the increasing emergence of resistance to azoles in C. albicans. New treatment approaches are needed to combat candidiasis especially in the dwindled supply of new effective and safe antifungals. The resistance to azoles is mainly attributed to export of azoles outside the cells by means of the efflux pump that confers cross resistance to all azoles including fluconazole (FLC). OBJECTIVES: This study aimed to investigate the possible efflux pump inhibiting activity of fusidic acid (FA) in C. albicans resistant isolates and the potential use of Fusidic acid in combination with fluconazole to potentiate the antifungal activity of fluconazole to restore its activity in the resistant C. albicans isolates. METHODS: The resistance of C. albicans isolates was assessed by determination of minimum inhibitory concentration. The effect of Fusidic acid at sub-inhibitory concentration on efflux activity was assayed by rhodamine 6G efflux assay and intracellular accumulation. Mice model studies were conducted to evaluate the anti-efflux activity of Fusidic acid and its synergistic effects in combination with fluconazole. Impact of Fusidic acid on ergosterol biosynthesis was quantified. The synergy of fluconazole when combined with Fusidic acid was investigated by determination of minimum inhibitory concentration. The cytotoxicity of Fusidic acid was tested against erythrocytes. The effect of Fusidic acid on efflux pumps was tested at the molecular level by real-time PCR and in silico study. In vivo vulvovaginitis mice model was used to confirm the activity of the combination in treating vulvovaginal candidiasis. RESULTS: Fusidic acid showed efflux inhibiting activity as it increased the accumulation of rhodamine 6G, a substrate for ABC-efflux transporter, and decreased its efflux in C. albicans cells. The antifungal activity of fluconazole was synergized when combined with Fusidic acid. Fusidic acid exerted only minimal cytotoxicity on human erythrocytes indicating its safety. The FA efflux inhibitory activity could be owed to its ability to interfere with efflux protein transporters as revealed by docking studies and downregulation of the efflux-encoding genes of both ABC transporters and MFS superfamily. Moreover, in vivo mice model showed that using fluconazole-fusidic acid combination by vaginal route enhanced fluconazole antifungal activity as shown by lowered fungal burden and a negligible histopathological change in vaginal tissue. CONCLUSION: The current findings highlight FA's potential as a potential adjuvant to FLC in the treatment of vulvovaginal candidiasis.


Assuntos
Candidíase Vulvovaginal , Candidíase , Humanos , Feminino , Animais , Camundongos , Fluconazol/farmacologia , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Candidíase Vulvovaginal/tratamento farmacológico , Ácido Fusídico/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Farmacorresistência Fúngica , Candida albicans , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Azóis/farmacologia , Testes de Sensibilidade Microbiana
16.
mSphere ; 9(3): e0078523, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38376205

RESUMO

Candida albicans is one of the most common causes of superficial and invasive fungal diseases in humans. Its ability to cause disease is closely linked to its ability to undergo a morphological transition from budding yeast to filamentous forms (hyphae and pseudohyphae). The extent to which C. albicans strains isolated from patients undergo filamentation varies significantly. In addition, the filamentation phenotypes of mutants involving transcription factors that positively regulate hyphal morphogenesis can also vary from strain to strain. Here, we characterized the virulence, in vitro and in vivo filamentation, and in vitro and in vivo hypha-associated gene expression profiles for four poorly filamenting C. albicans isolates and their corresponding deletion mutants of the repressor of filamentation NRG1. The two most virulent strains, 57055 and 78048, show robust in vivo filamentation but are predominately yeast phase under in vitro hypha induction; the two low-virulence strains (94015 and 78042) do not undergo filamentation well under either condition. In vitro, deletion of NRG1 increases hyphae formation in the SC5314 derivative SN250, but only pseudohyphae are formed in the clinical isolates. Deletion of NRG1 modestly increased the virulence of 78042, which was accompanied by increased expression of hypha-associated genes without an increase in filamentation. Strikingly, deletion of NRG1 in 78048 reduced filamentation in vivo, expression of candidalysin (ECE1), and virulence without dramatically altering establishment of infection. Thus, the function of the conserved repressor NRG1 in C. albicans shows strain-based heterogeneity during infection.IMPORTANCEClinical isolates of the human fungal pathogen Candida albicans show significant variation in their ability to undergo in vitro filamentation and in the function of well-characterized transcriptional regulators of filamentation. Here, we show that Nrg1, a key repressor of filamentation and filament specific gene expression in standard reference strains, has strain-dependent functions, particularly during infection. Most strikingly, loss of NRG1 function can reduce filamentation, hypha-specific gene expression such as the toxin candidalysin, and virulence in some strains. Our data emphasize that the functions of seemingly fundamental and well-conserved transcriptional regulators such as Nrg1 are contextual with respect to both environment and genetic backgrounds.


Assuntos
Candida albicans , Candidíase , Humanos , Candidíase/microbiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Virulência , Neuregulina-1/genética , Neuregulina-1/metabolismo
17.
Microbiol Spectr ; 12(4): e0356423, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364098

RESUMO

CHROMagar Candida Plus is a new formulation of chromogenic media designed for the detection and differentiation of major clinical Candida species, including Candida auris. The objective of this study is to evaluate CHROMagar Candida Plus when used according to manufacturer's instructions with a panel of 206 fungal isolates and 83 skin-swab specimens originally collected for C. auris colonization screening. Of the 68 C. auris isolates tested, 66/68 displayed the expected light-blue colony morphology and blue halo within 48 h. None of the remaining 138 non-auris isolates appeared similar to C. auris. CHROMagarCandida Plus was, therefore, inclusive to 97% of 68 C. auris isolates tested and supported visual exclusion of 100% of the 138 non-C. auris isolates tested. For the 83 colonization screening specimens, direct plating onto CHROMagarCandida Plus was 60% sensitive and 100% specific when compared to the enrichment broth gold-standard reference method. In sum, these findings demonstrate the utility of this media when working with isolates but also notable limitations when working with primary skin-swabs specimens when competing yeast species are present.IMPORTANCECandida auris is an emerging fungal pathogen of public health concern. As it continues to spread, it is important to publish evaluations of new diagnostic tools. In this study, we share our experience with a new chromogenic media which can help distinguish C. auris from related species.


Assuntos
Candida , Candidíase , Humanos , Candida auris , Candidíase/diagnóstico , Candidíase/microbiologia , Meios de Cultura , Corantes , Antifúngicos
18.
Microbiol Spectr ; 12(4): e0424723, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38415658

RESUMO

Cutaneous candidiasis, caused by Candida albicans, is a severe and frustrating condition, and finding effective treatments can be challenging. Therefore, the development of farnesol-loaded nanoparticles is an exciting breakthrough. Ethosomes are a novel transdermal drug delivery carrier that incorporates a certain concentration (10-45%) of alcohols into lipid vesicles, resulting in improved permeability and encapsulation rates compared to conventional liposomes. Farnesol is a quorum-sensing molecule involved in morphogenesis regulation in C. albicans, and these ethosomes offer a promising new approach to treating this common fungal infection. This study develops the formulation of farnesol-loaded ethosomes (farnesol-ethosomes) and assesses applications in treating cutaneous candidiasis induced by C. albicans in vitro and in vivo. Farnesol-ethosomes were successfully developed by ethanol injection method. Therapeutic properties of farnesol-ethosomes, such as particle size, zeta potential, and morphology, were well characterized. According to the results, farnesol-ethosomes demonstrated an increased inhibition effect on cells' growth and biofilm formation in C. albicans. In Animal infection models, treating farnesol-ethosomes by transdermal administration effectively relieved symptoms caused by cutaneous candidiasis and reduced fungal burdens in quantity. We also observed that ethosomes significantly enhanced drug delivery efficacy in vitro and in vivo. These results indicate that farnesol-ethosomes can provide future promising roles in curing cutaneous candidiasis. IMPORTANCE: Cutaneous candidiasis attributed to Candida infection is a prevalent condition that impacts individuals of all age groups. As a type of microbial community, biofilms confer benefits to host infections and mitigate the clinical effects of antifungal treatments. In C. albicans, the yeast-to-hypha transition and biofilm formation are effectively suppressed by farnesol through its modulation of multiple signaling pathway. However, the characteristics of farnesol such as hydrophobicity, volatility, degradability, and instability in various conditions can impose limitations on its effectiveness. Nanotechnology holds the potential to enhance the efficiency and utilization of this molecule. Treatment of farnesol-ethosomes by transdermal administration demonstrated a very remarkable therapeutic effect against C. albicans in infection model of cutaneous candidiasis in mice. Many patients suffering fungal skin infection will benefit from this study.


Assuntos
Candida albicans , Candidíase , Humanos , Animais , Camundongos , Farneseno Álcool/farmacologia , Farneseno Álcool/metabolismo , Farneseno Álcool/uso terapêutico , Administração Cutânea , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Antifúngicos/farmacologia , Biofilmes
19.
Braz J Microbiol ; 55(1): 391-402, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38261261

RESUMO

BACKGROUND: Candida auris is an emerging multidrug-resistant fungal pathogen associated with nosocomial infections and hospital outbreaks worldwide, presenting a serious global health threat. There has been a rapid emergence of scientific research publications focusing on therapeutic compounds, diagnostic techniques, control strategies, prevention, and understanding the epidemiology related to C. auris. OBJECTIVE: This study aims to provide the most up-to-date comprehensive and integrated examination of C. auris research subject and demonstrate that C. auris is indeed a topic of increasing interest. METHODS: The search query "candida-auris" was used as a topic term to find and retrieve relevant data published between 2009 and 15 June 2023, from the Web of Science Core Collection (WoSCC) database. In this work, the bibliometric analysis and network visualization were conducted using VOSviewer software, and Biblioshiny interface accessible through the Bibliometrix R-package on RStudio software. RESULTS: The yearly growth rate percentage (37.91%), along with the strong positive correlations between publications and citations (r = 0.981; p < 0.001), suggests heightened scholarly engagement in this topic. The USA, India, China, and the UK have emerged as pivotal contributors, with the Centers for Disease Control and Prevention (CDC) in the USA being the most productive institution. Current research hotspots in this field mainly focused on identifying and limiting transmission of the clonal strains, epidemiology, antifungal resistance, and in vitro antifungal susceptibility testing. CONCLUSION: This detailed bibliometric analysis in C. auris topic shows that this fungal pathogen has garnered growing attention and attracted progressively more scholars. This paper will help researchers to find without difficulty the relevant articles, research hotspots, influential authors, institutions, and countries related to the topic.


Assuntos
Candida , Candidíase , Humanos , Candidíase/microbiologia , Candida auris , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fungos , Testes de Sensibilidade Microbiana
20.
mBio ; 15(2): e0308023, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38193663

RESUMO

Candida auris is an emerging human fungal pathogen, first described in Japan in 2009, and first detected in the United States in 2016. Here, we report the first-ever description of C. auris colonizing a human pet, the first identification of C. auris in a non-human mammal in the United States and the first C. auris isolate from the state of Kansas. While analyzing the oral mycobiome of dogs from a shelter in Kansas, the oral swab from one dog was found to contain C. auris as well as three other fungal species. The presence of C. auris in a dog suggests the possibility of zoonotic transmission to humans. The isolate is a member of Clade IV, which has been found in patients in Chicago and Florida, while Clades I and III are the most prevalent in the United States. The isolate is resistant to fluconazole, terbinafine, and amphotericin B but susceptible to caspofungin, consistent with the drug-resistant characteristics of many human C. auris isolates. The source of C. auris transient colonization in this dog is unknown, and there is no evidence that it was further transmitted to humans, other dogs in the shelter, or pets in its adopted household. Isolation of C. auris from a dog in Kansas has public health implications as a potential emerging source for the zoonotic spread of this pathogenic fungus, and for the development of antifungal resistance.IMPORTANCECandida auris is an emerging fungal infection of humans and is particularly problematic because it is multi-drug resistant and difficult to treat. It is also known to be spread from person to person by contact and can remain on surfaces for long periods of time. In this report, a dog in a shelter in Kansas is found to be colonized with Candida auris. This is the first study to document the presence of Candida auris on a pet, the first to document C. auris presence on a non-human mammal in the United States, and the first to report an isolate of C. auris within the state of Kansas. The presence of C. auris in a pet dog raises the possibility of zoonotic transmission from pets to human or vice versa.


Assuntos
Antifúngicos , Candidíase , Cães , Humanos , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Candidíase/microbiologia , Candida auris , Kansas , Boca , Mamíferos , Testes de Sensibilidade Microbiana
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