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1.
J Clin Immunol ; 44(7): 163, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008214

RESUMO

BACKGROUND: Cryptococcosis is a life-threatening disease caused by Cryptococcus neoformans or C. gattii. Neutralizing autoantibodies (auto-Abs) against granulocyte-macrophage colony-stimulating factor (GM-CSF) in otherwise healthy adults with cryptococcal meningitis have been described since 2013. We searched for neutralizing auto-Abs in sera collected from Colombian patients with non-HIV-associated cryptococcosis in a retrospective national cohort from 1997 to 2016. METHODS: We reviewed clinical and laboratory records and assessed the presence of neutralizing auto-Abs against GM-CSF in 30 HIV negative adults with cryptococcosis (13 caused by C. gattii and 17 caused by C. neoformans). RESULTS: We detected neutralizing auto-Abs against GM-CSF in the sera of 10 out of 13 (77%) patients infected with C. gattii and one out of 17 (6%) patients infected with C. neoformans. CONCLUSIONS: We report eleven Colombian patients diagnosed with cryptococcosis who had auto-Abs that neutralize GM-CSF. Among these patients, ten were infected with C. gattii and only one with C. neoformans.


Assuntos
Anticorpos Neutralizantes , Autoanticorpos , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Masculino , Colômbia , Feminino , Adulto , Cryptococcus gattii/imunologia , Pessoa de Meia-Idade , Cryptococcus neoformans/imunologia , Criptococose/imunologia , Criptococose/diagnóstico , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Estudos Retrospectivos , Soronegatividade para HIV/imunologia , Adulto Jovem , Idoso
2.
Braz J Microbiol ; 55(3): 2463-2471, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38963475

RESUMO

Cryptococcus gattii, an environmental fungus, is one of the agents of cryptococcosis. The influence of agrochemicals on fungal resistance to antifungals is widely discussed. However, the effects of benomyl (BEN) on fungal interaction with different hosts is still to be understood. Here we studied the influence of adaptation to BEN in the interaction with a plant model, phagocytes and with Tenebrio molitor. First, the strain C. gattii L24/01 non-adapted (NA), adapted (A) to BEN, and adapted with further culture on drug-free media (10p) interact with Nicotiana benthamiana, with a peak in the yeast burden on the 7th day post-inoculation. C. gattii L24/01 A and 10p provided lower fungal burden, but these strains increased cell diameter and capsular thickness after the interaction, together with decreased fungal growth. The strains NA and A showed reduced ergosterol levels, while 10p exhibited increased activity of laccase and urease. L24/01 A recovered from N. benthamiana was less engulfed by murine macrophages, with lower production of reactive oxygen species. This phenotype was accompanied by increased ability of this strain to grow inside macrophages. Otherwise, L24/01 A showed reduced virulence in the T. molitor larvae model. Here, we demonstrate that the exposure to BEN, and interaction with plants interfere in the morphophysiology and virulence of the C. gattii.


Assuntos
Cryptococcus gattii , Nicotiana , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/crescimento & desenvolvimento , Cryptococcus gattii/metabolismo , Cryptococcus gattii/fisiologia , Animais , Camundongos , Nicotiana/microbiologia , Macrófagos/microbiologia , Criptococose/microbiologia , Tenebrio/microbiologia , Agroquímicos/farmacologia , Antifúngicos/farmacologia , Doenças das Plantas/microbiologia
3.
Artigo em Português | MEDLINE | ID: mdl-39052027

RESUMO

The literature holds few descriptions on immune response findings for laryngeal cryptococcosis. Immunology has been more extensively described in cases involving the central nervous system and the lungs, although many of these studies were conducted in animal models. We aimed to analyze the clinical and immunological characteristics of three patients with laryngeal cryptococcosis. We observed a weak participation of the innate immune response, whereas adaptive immunity showed the predominance of a Th2-type response over a Th1-type response. Most cases occur in male older adults with immunosuppressive conditions, of which HIV infection was absent. Hoarseness configured the main symptom. We found a disease that was restricted to the larynx and possibly the lungs by contiguity. Patients with hoarseness and lesions in nasal endoscopy should be investigated for cryptococcosis by a biopsy of the larynx, including with negative serum cryptococcal antigen. The immunological aspects of our findings of laryngeal involvement resembled those in the most commonly affected systems.


Assuntos
Criptococose , Doenças da Laringe , Humanos , Criptococose/imunologia , Doenças da Laringe/imunologia , Doenças da Laringe/microbiologia
4.
Mycoses ; 67(7): e13767, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004801

RESUMO

BACKGROUND: The radiological manifestations of central nervous system (CNS) cryptococcosis are diverse and often subtle. There is heterogeneity on how different neuroimaging patterns impact prognosis. This study aims to assess the association between the neuroimaging and clinical outcomes of CNS cryptococcosis. METHODS: All patients with CNS cryptococcosis between July 2017 and April 2023 who underwent brain magnetic resonance imaging (MRI) were included. The primary outcome was mortality during hospitalisation. Secondary outcomes were readmission, ventricular shunting, duration of hospitalisation and time to the first negative cerebrospinal fluid culture. We compared the outcomes for each of the five main radiological findings on the brain MRI scan. RESULTS: We included 46 proven CNS cryptococcosis cases. The two main comorbidity groups were HIV infection (20, 43%) and solid organ transplantation (10, 22%), respectively. Thirty-nine patients exhibited at least one radiological abnormality (85%), with the most common being meningeal enhancement (34, 74%). The mortality rates occurred at 11% (5/46) during hospitalisation. We found no significant disparities in mortality related to distinct radiological patterns. The presence of pseudocysts was significantly associated with the need for readmission (p = .027). The ventricular shunting was significantly associated with the presence of pseudocysts (p = .005) and hydrocephalus (p = .044). CONCLUSION: In this study, there is no association between brain MRI findings and mortality. Larger studies are needed to evaluate this important issue.


Assuntos
Criptococose , Imageamento por Ressonância Magnética , Neuroimagem , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Neuroimagem/métodos , Criptococose/diagnóstico por imagem , Criptococose/mortalidade , Criptococose/microbiologia , Adulto , Idoso , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Infecções Fúngicas do Sistema Nervoso Central/diagnóstico por imagem , Infecções Fúngicas do Sistema Nervoso Central/mortalidade , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Prognóstico , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/mortalidade , Hospitalização , Infecções por HIV/complicações
5.
Immunotherapy ; 16(11): 733-748, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38940276

RESUMO

Aim: Cryptococcus gattii causes a severe fungal infection with high mortality rate among immunosuppressed and immunocompetent individuals. Due to limitation of current antifungal treatment, new immunotherapeutic approaches are explored.Methods: This study investigated an immunization strategy utilizing heat-inactivated C. gattii with ArtinM as an adjuvant. C57BL/6 mice were intranasally immunized with heat-killed C. gattii and ArtinM was administrated either before immunization or along with HK-C. gattii. Mice were infected with C. gattii and the efficacy of the immunization protocol was evaluated.Results: Mice that received ArtinM exhibited increased levels of IL-10 and relative expression of IL-23 in the lungs, reduced fungal burden and preserved tissue integrity post-infection.Conclusion: Adjuvant ArtinM improved immunization against C. gattii infection in C57BL/6 mice.


Cryptococcus gattii is a fungus that can make lungs sick. Right now, there are no good treatments for it, so scientists are trying to find new ways to fight it. In a recent study, they tested a type of immunotherapy called ArtinM to see if it could help. When they gave ArtinM to mice, the mice got healthier and had less fungus in their lungs. This means ArtinM might be able to help fight this fungus.


Assuntos
Adjuvantes Imunológicos , Criptococose , Cryptococcus gattii , Camundongos Endogâmicos C57BL , Animais , Cryptococcus gattii/imunologia , Camundongos , Criptococose/imunologia , Adjuvantes Imunológicos/administração & dosagem , Vacinas Fúngicas/imunologia , Modelos Animais de Doenças , Feminino , Humanos
6.
mBio ; 15(7): e0103124, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38916308

RESUMO

Cryptococcus neoformans causes cryptococcosis, one of the most prevalent fungal diseases, generally characterized by meningitis. There is a limited and not very effective number of drugs available to combat this disease. In this manuscript, we show the host defense peptide mimetic brilacidin (BRI) as a promising antifungal drug against C. neoformans. BRI can affect the organization of the cell membrane, increasing the fungal cell permeability. We also investigated the effects of BRI against the model system Saccharomyces cerevisiae by analyzing libraries of mutants grown in the presence of BRI. In S. cerevisiae, BRI also affects the cell membrane organization, but in addition the cell wall integrity pathway and calcium metabolism. In vivo experiments show BRI significantly reduces C. neoformans survival inside macrophages and partially clears C. neoformans lung infection in an immunocompetent murine model of invasive pulmonary cryptococcosis. We also observed that BRI interacts with caspofungin (CAS) and amphotericin (AmB), potentiating their mechanism of action against C. neoformans. BRI + CAS affects endocytic movement, calcineurin, and mitogen-activated protein kinases. Our results indicate that BRI is a novel antifungal drug against cryptococcosis. IMPORTANCE: Invasive fungal infections have a high mortality rate causing more deaths annually than tuberculosis or malaria. Cryptococcosis, one of the most prevalent fungal diseases, is generally characterized by meningitis and is mainly caused by two closely related species of basidiomycetous yeasts, Cryptococcus neoformans and Cryptococcus gattii. There are few therapeutic options for treating cryptococcosis, and searching for new antifungal agents against this disease is very important. Here, we present brilacidin (BRI) as a potential antifungal agent against C. neoformans. BRI is a small molecule host defense peptide mimetic that has previously exhibited broad-spectrum immunomodulatory/anti-inflammatory activity against bacteria and viruses. BRI alone was shown to inhibit the growth of C. neoformans, acting as a fungicidal drug, but surprisingly also potentiated the activity of caspofungin (CAS) against this species. We investigated the mechanism of action of BRI and BRI + CAS against C. neoformans. We propose BRI as a new antifungal agent against cryptococcosis.


Assuntos
Antifúngicos , Criptococose , Cryptococcus neoformans , Saccharomyces cerevisiae , Antifúngicos/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Animais , Camundongos , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Modelos Animais de Doenças , Macrófagos/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Testes de Sensibilidade Microbiana , Caspofungina/farmacologia , Feminino , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Anfotericina B/farmacologia
7.
Methods Mol Biol ; 2775: 171-193, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758318

RESUMO

The interaction between macrophages and Cryptococcus neoformans is crucial in the pathogenesis of cryptococcosis. These phagocytes are important immune effectors, but also a niche in which facultative intracellular parasites, such as C. neoformans, thrive. Consequently, phagocytosis of cryptococcal cells and its outcomes are very frequently studied. One major issue with several of the tests used for this, however, is that macrophage-C. neoformans interaction does not always result in phagocytosis, as fungi may be attached to the external surface of the phagocyte. The most used methodologies to study phagocytosis of cryptococcal cells have varying degrees of precision in separating fungi that are truly internalized from those that are outside macrophages. Here we describe two assays to measure phagocytosis that can differentiate internal from external C. neoformans cells.


Assuntos
Criptococose , Cryptococcus neoformans , Macrófagos , Fagocitose , Cryptococcus neoformans/imunologia , Macrófagos/microbiologia , Macrófagos/imunologia , Macrófagos/metabolismo , Criptococose/microbiologia , Criptococose/imunologia , Animais , Camundongos , Humanos , Interações Hospedeiro-Patógeno/imunologia
8.
Methods Mol Biol ; 2775: 307-328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758326

RESUMO

The importance of humoral immunity to fungal infections remains to be elucidated. In cryptococcosis, patients that fail to generate antibodies against antigens of the fungus Cryptococcus neoformans are more susceptible to the disease, demonstrating the importance of these molecules to the antifungal immune response. Historically, antibodies against C. neoformans have been applied in diagnosis, therapeutics, and as important research tools to elucidate fungal biology. Throughout the process of generating monoclonal antibodies (mAbs) from a single B-cell clone and targeting a single epitope, several immunization steps might be required for the detection of responsive antibodies to the antigen of interest in the serum. This complex mixture of antibodies comprises the polyclonal antibodies. To obtain mAbs, B-lymphocytes are harvested (from spleen or peripheral blood) and fused with tumor myeloma cells, to generate hybridomas that are individually cloned and specifically screened for mAb production. In this chapter, we describe all the necessary steps, from the immunization to polyclonal antibody harvesting, hybridoma generation, and mAb production and purification. Additionally, we discuss new cutting-edge approaches for generating interspecies mAbs, such as humanized mAbs, or for similar species in distinct host backgrounds.


Assuntos
Anticorpos Antifúngicos , Anticorpos Monoclonais , Cryptococcus neoformans , Hibridomas , Cryptococcus neoformans/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Animais , Humanos , Hibridomas/imunologia , Anticorpos Antifúngicos/imunologia , Anticorpos Antifúngicos/isolamento & purificação , Camundongos , Linfócitos B/imunologia , Criptococose/imunologia , Criptococose/diagnóstico , Antígenos de Fungos/imunologia , Imunização
9.
Methods Mol Biol ; 2775: 359-365, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758329

RESUMO

Extracellular vesicles (EVs) are produced by all domains of life. In fungal pathogens, they participate in virulence mechanisms and/or induce protective immunity, depending on the pathogenic species. EVs produced by pathogenic members of the Cryptococcus genus mediate virulence, antifungal resistance, as well as humoral and cell-mediated immunity. The isolation of cryptococcal EVs has been laborious and time-consuming for years. In this chapter, we detail a fast protocol for the isolation and analysis of EVs produced by members of the Cryptococcus genus.


Assuntos
Cryptococcus , Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Criptococose/microbiologia , Criptococose/imunologia , Humanos
10.
Folia Microbiol (Praha) ; 69(6): 1247-1254, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38652436

RESUMO

Cryptococcosis is an invasive mycosis caused mainly by Cryptococcus gattii and C. neoformans and is treated with amphotericin B (AMB), fluconazole and 5-fluorocytosine. However, antifungal resistance, limited and toxic antifungal arsenal stimulate the search for therapeutic strategies such as drug repurposing. Among the repurposed drugs studied, the selective serotonin reuptake inhibitors (SSRIs) have shown activity against Cryptococcus spp. However, little is known about the antifungal effect of duloxetine hydrochloride (DH), a selective serotonin and norepinephrine reuptake inhibitor (SSNRI), against C. neoformans and C. gattii. In this study, DH inhibited the growth of several C. neoformans and C. gattii strains at concentrations ranging from 15.62 to 62.50 µg/mL. In addition, DH exhibited fungicidal activity ranging from 15.62 to 250 µg/mL. In biofilm, DH treatment reduced Cryptococcus spp. biomass at a level comparable to AMB, with a significant reduction (85%) for C. neoformans biofilms. The metabolic activity of C. neoformans and C. gattii biofilms decreased significantly (99%) after treatment with DH. Scanning electron micrographs confirmed the anti-biofilm activity of DH, as isolated cells could be observed after treatment. In conclusion, DH showed promising antifungal activity against planktonic cells and biofilms of C. neoformans and C. gattii, opening perspectives for further studies with DH in vivo.


Assuntos
Antifúngicos , Biofilmes , Cryptococcus gattii , Cryptococcus neoformans , Cloridrato de Duloxetina , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Cryptococcus gattii/efeitos dos fármacos , Cloridrato de Duloxetina/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/crescimento & desenvolvimento , Criptococose/tratamento farmacológico , Criptococose/microbiologia
11.
Braz J Microbiol ; 55(2): 1369-1380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38619732

RESUMO

Cryptococcosis is one of the major life-threatening opportunistic/systemic fungal diseases of worldwide occurrence, which can be asymptomatic or establish pneumonia and meningoencephalitis mainly in immunosuppressed patients, caused by the Cryptococcus neoformans and C. gattii species complexes. Acquisition is by inhaling fungal propagules from avian droppings, tree hollows and decaying wood, and the association of the molecular types with geographic origin, virulence and antifungal resistance have epidemiological importance. Since data on cryptococcosis in Alagoas are limited, we sought to determine the molecular types of etiological agents collected from clinical and environmental sources. We evaluated 21 isolates previously collected from cerebrospinal fluid and from environment sources (pigeon droppings and tree hollows) in Maceió-Alagoas (Brazil). Restriction fragment length polymorphism of URA5 gene was performed to characterize among the eight standard molecular types (VNI-VNIV and VGI-VGIV). Among isolates, 66.67% (14) were assigned to C. neoformans VNI - 12 of them (12/14) recovered from liquor and 2 from a tree hollow (2/14). One isolate from pigeon droppings (4.76%) corresponded to C. neoformans VNIV, while five strains from tree hollows and one from pigeon droppings (6, 28.57%) to C. gattii VGII. VNI-type was present in clinical and environmental samples and most C. neoformans infections were observed in HIV-positive patients, while types VNIV and VGII were prevalent in environmental sources in Alagoas. This is the first molecular characterization of Cryptococcus spp. in Alagoas, our study provides additional information on the ecoepidemiology of Cryptococcus spp. in Brazil, contributing to a closer view of the endemic species.


Assuntos
Columbidae , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Microbiologia Ambiental , Cryptococcus neoformans/genética , Cryptococcus neoformans/isolamento & purificação , Cryptococcus neoformans/classificação , Brasil/epidemiologia , Criptococose/microbiologia , Criptococose/epidemiologia , Cryptococcus gattii/genética , Cryptococcus gattii/isolamento & purificação , Cryptococcus gattii/classificação , Humanos , Animais , Columbidae/microbiologia , Técnicas de Tipagem Micológica , Polimorfismo de Fragmento de Restrição , Fezes/microbiologia , Genótipo
12.
Andes Pediatr ; 95(1): 77-83, 2024 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-38587347

RESUMO

Pulmonary cryptococcosis is a lung infection caused by the Cryptococcus yeast. It is rare in pediatrics, especially in immunocompetent children. The diagnosis of pulmonary cryptococcosis can be challenging due to the low specificity of symptoms, low index of suspicion, and limited diagnostic resources. OBJECTIVE: To describe a clinical case of pulmonary cryptococcosis in an immunocompetent adolescent, detailing the diagnostic approach. CLINICAL CASE: A 15-year-old patient, previously healthy, from a rural town, who consulted due to cough and a 1-month rib stitch pain, without fever or associated respiratory difficulty, with two images of condensation in the left lung on the chest x-ray. In the Computed Tomography, the images showed a nodular appearance. Due to suspicion of neoplastic pathology, a Positron Emission Tomography was performed, which showed hypermetabolic nodular lesions. The tomographic characteristics could correspond to fungal or granulomatous involvement. Considering the images and epidemiological risk factors such as rural origin and contact with bird droppings, the possibility of a mycosis was considered. A lung needle biopsy was performed under tomographic guidance. Cryptococcus neoformans was identified in the microbiology laboratory culture. The patient received treatment with itraconazole and fluconazole with good clinical and imaging response after 10 months of therapy and follow-up. CONCLUSION: In immunocompetent patients with a nonspecific clinical presentation, images can guide the diagnosis of pulmonary cryptococcosis, and an etiological search is essential to confirm it. In our case, the CT-guided needle biopsy was of great diagnostic utility.


Assuntos
Criptococose , Cryptococcus neoformans , Pneumopatias Fúngicas , Adolescente , Humanos , Biópsia , Criptococose/diagnóstico por imagem , Criptococose/tratamento farmacológico , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/tratamento farmacológico , Tomografia Computadorizada por Raios X
13.
BMC Infect Dis ; 24(1): 406, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627642

RESUMO

BACKGROUND: Opportunistic infections (OIs) are common causes of mortality among people living with HIV (PLHIV). We determined prevalence and 30-day mortality due to histoplasmosis, cryptococcosis, and TB in PLHIV with advanced HIV disease (AHD). METHODS: PLHIV 18 years and older, with a CD4 + T-cell count of less than 350 cells/mm3 newly diagnosed with HIV infection or re-engaged in care after being without ART for more than 90 days (Group A). The second group included symptomatic PLHIV regardless of ART status or CD4 + T-cell count (Group B); all followed for 30 days. Detection of Histoplasma Ag (HisAg) in urine was done by enzyme immunoassay (EIA), Cryptococcus antigen (CrAg) was detected in serum and cerebrospinal fluid (CSF) specimens by lateral flow assay (LFA), and lipoarabinomannan (LAM) detection in urine was by LFA (TB LAM) and in sputum by GeneXpert for diagnosis of Mycobacterium infections. RESULTS: From August 2021 to June 2022, 491 PLHIV were enrolled; 482 (98%) had a CD4 + T-cell result, and 381 patients (79%) were classified with AHD according to CD4 + T-cell count (< 200 CD4/mm3). Frequency of an OI was 38% (n = 145/381). Antigen test positivity rate was 16% (72/467) for TB-LAM, 9% (43/464) for HisAg, and 11% (51/484) for CrAg. Twenty-one of 34 (62%) patients receiving CSF CrAg tests were positive, confirming meningitis. Significant differences in 30-day mortality were observed in patients with an OI (16%) vs. no OI (7%) (p = 0.002). Mortality was highest in patients with histoplasmosis (25%), co-infection (22%), cryptococcosis (18% overall; 19% for cryptococcal meningitis), and TB (10%). CONCLUSIONS: TB and fungal OIs, including co-infection, were common in PLHIV in Paraguay and had high associated mortality. Laboratories and health facilities need access to CD4 + T-cell testing and rapid diagnostic assays.


Assuntos
Coinfecção , Criptococose , Infecções por HIV , Histoplasmose , Infecções Oportunistas , Tuberculose , Humanos , Infecções por HIV/epidemiologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Testes de Diagnóstico Rápido , Paraguai/epidemiologia , Criptococose/complicações , Criptococose/diagnóstico , Criptococose/epidemiologia , Tuberculose/complicações , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Antígenos de Fungos
14.
J Med Microbiol ; 73(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38530134

RESUMO

Introduction. Cryptococcal biofilms have been associated with persistent infections and antifungal resistance. Therefore, strategies, such as the association of natural compounds and antifungal drugs, have been applied for the prevention of biofilm growth. Moreover, the Caenorhabditis elegans pathogenicity model has been used to investigate the capacity to inhibit the pathogenicity of Cryptococcus neoformans sensu stricto.Hypothesis. Anthraquinones and antifungals are associated with preventing C. neoformans sensu stricto biofilm formation and disrupting these communities. Antraquinones reduced the C. neoformans sensu stricto pathogenicity in the C. elegans model.Aim. This study aimed to evaluate the in vitro interaction between aloe emodin, barbaloin or chrysophanol and itraconazole or amphotericin B against growing and mature biofilms of C. neoformans sensu stricto.Methodology. Compounds and antifungal drugs were added during biofilm formation or after 72 h of growth. Then, the metabolic activity was evaluated by the MTT reduction assay, the biomass by crystal-violet staining and the biofilm morphology by confocal laser scanning microscopy. C. neoformans sensu stricto's pathogenicity was investigated using the nematode C. elegans. Finally, pathogenicity inhibition by aloe emodin, barbarloin and chrysophanol was investigated using this model.Results. Anthraquinone-antifungal combinations affected the development of biofilms with a reduction of over 60 % in metabolic activity and above 50 % in biomass. Aloe emodin and barbaloin increased the anti-biofilm activity of antifungal drugs. Chrysophanol potentiated the effect of itraconazole against C. neoformans sensu stricto biofilms. The C. elegans mortality rate reached 76.7 % after the worms were exposed to C. neoformans sensu stricto for 96 h. Aloe emodin, barbaloin and chrysophanol reduced the C. elegans pathogenicity with mortality rates of 61.12 %, 65 % and 53.34 %, respectively, after the worms were exposed for 96 h to C. neoformans sensu stricto and these compounds at same time.Conclusion. These results highlight the potential activity of anthraquinones to increase the effectiveness of antifungal drugs against cryptococcal biofilms.


Assuntos
Antracenos , Criptococose , Cryptococcus neoformans , Animais , Antifúngicos/farmacologia , Caenorhabditis elegans , Itraconazol , Virulência , Antraquinonas/farmacologia , Biofilmes
15.
Washington, D.C.; PAHO; 2024-03-22. (PAHO/UFCSPA/CDE/HT/23-0015).
Não convencional em Inglês | PAHO-IRIS | ID: phr-59381

RESUMO

People living with HIV (PLHIV) with severe advanced disease are at high risk of developing opportunistic infections and may face barriers related to diagnosis and treatment. The objective of this study was to describe insights, experiences and perspectives around the feasibility of implementing a package for the rapid diagnosis of frequent opportunistic infections among patients with advanced HIV, in order to support the development and implementation of HIV care policies. The study was carried out between June 30 and October 30, 2023, comprising two focus groups with health professionals involved in the rapid diagnosis intervention (n=10); four in-depth interviews with health managers dedicated to HIV care policies; and 12 interviews with patients with advanced HIV. The intervention in question was considered relevant for allowing a more timely diagnosis of diseases that are difficult to investigate. Patient compliance was generally collaborative, especially in research hospitals, but more vulnerable patients may require expanded psychosocial support. Among the barriers, delays in results, communication challenges between professionals and patients were highlighted, as well as the lack of alignment in the flow of exam request, collection, results and communication for patients and the extended team. At the management level, the importance of integrating the intervention into the line of care for patients with HIV was highlighted. It is relevant to investigate the issue of social determinants of HIV/AIDS mortality in the future to provide valuable insights into improving prevention and treatment strategies.


Assuntos
Tuberculose , Histoplasmose , Criptococose , HIV , Síndrome da Imunodeficiência Adquirida , Infecções Oportunistas , Política de Saúde , Doenças Transmissíveis , Brasil
16.
Int J Antimicrob Agents ; 63(5): 107157, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38548248

RESUMO

Cryptococcus neoformans is responsible for over 100 000 deaths annually, and the treatment of this fungal disease is expensive and not consistently effective. Unveiling new therapeutic avenues is crucial. Previous studies have suggested that the anthelmintic drug fenbendazole is an affordable and nontoxic candidate to combat cryptococcosis. However, its mechanism of anticryptococcal activity has been only superficially investigated. In this study, we examined the global cellular response of C. neoformans to fenbendazole using a proteomic approach (data are available via ProteomeXchange with identifier PXD047041). Fenbendazole treatment mostly impacted the abundance of proteins related to metabolic pathways, RNA processing, and intracellular traffic. Protein kinases, in particular, were significantly affected by fenbendazole treatment. Experimental validation of the proteomics data using a collection of C. neoformans mutants led to the identification of critical roles of five protein kinases in fenbendazole's antifungal activity. In fact, mutants lacking the expression of genes encoding Chk1, Tco2, Tco3, Bub1, and Sch9 kinases demonstrated greater resistance to fenbendazole compared to wild-type cells. In combination with the standard antifungal drug amphotericin B, fenbendazole reduced the cryptococcal burden in mice. These findings not only contribute to the elucidation of fenbendazole's mode of action but also support its use in combination therapy with amphotericin B. In conclusion, our data suggest that fenbendazole holds promise for further development as an anticryptococcal agent.


Assuntos
Antifúngicos , Criptococose , Cryptococcus neoformans , Fenbendazol , Proteínas Quinases , Proteômica , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/genética , Antifúngicos/farmacologia , Animais , Fenbendazol/farmacologia , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Camundongos , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Anfotericina B/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Testes de Sensibilidade Microbiana , Modelos Animais de Doenças , Farmacorresistência Fúngica/genética
17.
Future Microbiol ; 19(7): 621-630, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38497911

RESUMO

Antifungal infections are becoming a major concern to human health due to antimicrobial resistance. Echinocandins have been promising agents against resistant fungal infections, primarily caspofungin, which has a more effective mechanism of action than azoles and polyenes. However, fungi such as Cryptococcus neoformans appear to be inheritably resistant to these drugs, which is concerning due to the high clinical importance of C. neoformans. In this review, we review the history of C. neoformans and the treatments used to treat antifungals over the years, focusing on caspofungin, while highlighting the C. neoformans problem and possible explanations for its inherent resistance.


Caspofungin is a drug used to treat several types of fungal infections. Resistance to caspofungin is a huge problem, especially in those that are immunocompromised. It is important to understand the history of caspofungin discovery, its clinical applications and its mechanism of action, as well as if a new drug target could be used overcome resistance. This review may perform guide new studies combining caspofungin with other drugs and indicate new potential targets for caspofungin.


Assuntos
Antifúngicos , Caspofungina , Criptococose , Cryptococcus neoformans , Farmacorresistência Fúngica , Caspofungina/uso terapêutico , Caspofungina/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Humanos , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Equinocandinas/uso terapêutico , Equinocandinas/farmacologia , Animais , Testes de Sensibilidade Microbiana , Lipopeptídeos/uso terapêutico , Lipopeptídeos/farmacologia
19.
Rev Soc Bras Med Trop ; 57: e008002023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324809

RESUMO

Previously considered saprobe and non-pathogenic, the fungus Papiliotrema laurentii (formerly known as Cryptococcus laurentii), is rarely associated with human infection. Nevertheless, there has been an increase in reported infections by non-neoformans cryptococci. After a literature search on the Cochrane Library, LILACS, SciELO, MEDLINE, PubMed, and PMC (PubMed Central) databases, we conclude that this is the first case report of fungemia and probable meningitis caused by Papiliotrema laurentii in a previously immunocompetent host with associated COVID-19.


Assuntos
Basidiomycota , COVID-19 , Criptococose , Cryptococcus , Fungemia , Humanos , Fungemia/complicações , Fungemia/diagnóstico , Fungemia/microbiologia , Criptococose/microbiologia , COVID-19/complicações , SARS-CoV-2
20.
Int J Surg Pathol ; 32(1): 165-181, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37143300

RESUMO

Cryptococcosis is a neglected fungal disease. The scarcity of studies on oral cryptococcosis is certainly due to rarity and/or underreporting of the disease, especially in Brazil. We describe an example of orofacial cryptococcosis affecting a 57-year-old man after heart transplantation, who presented with multiple erythematous ulcers and erosions distributed in the chin, nasal cavity, labial mucosa, hard palate, and buccal vestibule. Computed tomography revealed opacities and micronodules in the lungs. Histopathological features of the oral and pulmonary lesions were compatible with Cryptococcus spp. Amphotericin B and fluconazole were used for treatment during hospitalization and itraconazole for prolonged therapy after hospital discharge. The patient has been under follow up for 6 months without signs of disease. According to a review conducted in PubMed, Web of Science, Scopus, Embase, and LILACS for data analysis of oral cryptococcosis, 26 reports were described in the literature. Predilection for men was observed (85%), with a male:female ratio of 5.5:1. The mean age of the individuals was 49 ± 15.3 years. Oral cryptococcosis mostly presented as an ulcer (n = 17). The palate and tongue were the most affected sites (n = 9 for each). Amphotericin B was the primary therapy utilized in most patients. Seventeen (65%) individuals survived. Knowledge of the clinicodemographic aspects of oral cryptococcosis is important for clinicians in decision making and surveillance.


Assuntos
Criptococose , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Fluconazol/uso terapêutico
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