Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Más filtros

País/Región como asunto
País de afiliación
Intervalo de año de publicación
1.
Mem Inst Oswaldo Cruz ; 114: e190075, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31038549

RESUMEN

BACKGROUND: The elimination of malaria depends on the blocking of transmission and of an effective treatment. In Brazil, artemisinin therapy was introduced in 1991, and here we present a performance overview during implementation outset years. METHODS: It is a retrospective cohort (1991 to 2002) of patients treated in a tertiary centre of Manaus, with positive microscopic diagnosis of Plasmodium falciparum malaria, under treatment with using injectable or rectal artemisinin derivatives, and followed over 35-days to evaluate parasite clearance, death and recurrence. FINDINGS: This cohort outcome resulted 97.6% (1554/1593) of patients who completed the 35-day follow-up, 0.6% (10/1593) of death and 1.8% (29/1593) of follow-up loss. All patients that died and those that presented parasitaemia recurrence had pure P. falciparum infections and received monotherapy. Considering patients who completed 35-day treatment, 98.2% (1527/1554) presented asexual parasitaemia clearance until D4 and 1.8% (27/1554) between D5-D10. It is important to highlight that had no correlation between the five treatment schemes and the sexual parasite clearance. Finally, it is noteworthy that we were able to observe also gametocytes carriage during all follow-up (D0-D35). MAIN CONCLUSIONS: Artemisinin derivatives remained effective in the treatment of falciparum malaria during first 12-years of use in north area of Brazil.


Asunto(s)
Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Malaria Falciparum/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
2.
Fungal Genet Biol ; 95: 13-23, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27496542

RESUMEN

The ability to respond to stressful conditions is essential for most living organisms. In pathogenic organisms, this response is required for effective transition from a saprophytic lifestyle to the establishment of pathogenic interactions within a susceptible host. Hyperosmotic stress has been used as a model to study signal transduction and seems to cause many cellular adaptations, including the alteration of protein expression and cellular volume as well as size regulation. In this work, we evaluated the proteomic profile of Paracoccidioides lutzii Pb01 yeast cells during osmotic stress induced by potassium chloride. We performed a high accuracy proteomic technique (NanoUPLC-MS(E)) to identify differentially expressed proteins during osmotic shock. The data describe an osmoadaptative response of this fungus when subjected to this treatment. Proteins involved in the synthesis of cell wall components were modulated, which suggested cell wall remodeling. In addition, alterations in the energy metabolism were observed. Furthermore, proteins involved in amino acid metabolism and hydrogen peroxide detoxification were modulated during osmotic stress. Our study suggests that P. lutzii Pb01. presents a vast osmoadaptative response that is composed of different proteins that act together to minimize the effects caused by osmotic stress.


Asunto(s)
Adaptación Fisiológica , Proteínas Fúngicas/metabolismo , Presión Osmótica , Paracoccidioides/metabolismo , Paracoccidioides/fisiología , Proteómica/métodos , Aminoácidos/metabolismo , Pared Celular/química , Pared Celular/metabolismo , Metabolismo Energético , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Glucanos/biosíntesis , Glicerol/metabolismo , Glicerolfosfato Deshidrogenasa/metabolismo , Peróxido de Hidrógeno/metabolismo , Paracoccidioides/efectos de los fármacos , Cloruro de Potasio/farmacología , Transducción de Señal
3.
BMC Microbiol ; 15: 53, 2015 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-25888027

RESUMEN

BACKGROUND: Despite being important thermal dimorphic fungi causing Paracoccidioidomycosis, the pathogenic mechanisms that underlie the genus Paracoccidioides remain largely unknown. Microbial pathogens express molecules that can interact with human plasminogen, a protein from blood plasma, which presents fibrinolytic activity when activated into plasmin. Additionally, plasmin exhibits the ability of degrading extracellular matrix components, favoring the pathogen spread to deeper tissues. Previous work from our group demonstrated that Paracoccidioides presents enolase, as a protein able to bind and activate plasminogen, increasing the fibrinolytic activity of the pathogen, and the potential for adhesion and invasion of the fungus to host cells. By using proteomic analysis, we aimed to identify other proteins of Paracoccidioides with the ability of binding to plasminogen. RESULTS: In the present study, we employed proteomic analysis of the secretome, in order to identify plasminogen-binding proteins of Paracoccidioides, Pb01. Fifteen proteins were present in the fungal secretome, presenting the ability to bind to plasminogen. Those proteins are probable targets of the fungus interaction with the host; thus, they could contribute to the invasiveness of the fungus. For validation tests, we selected the protein fructose 1,6-bisphosphate aldolase (FBA), described in other pathogens as a plasminogen-binding protein. The protein FBA at the fungus surface and the recombinant FBA (rFBA) bound human plasminogen and promoted its conversion to plasmin, potentially increasing the fibrinolytic capacity of the fungus, as demonstrated in fibrin degradation assays. The addition of rFBA or anti-rFBA antibodies was capable of reducing the interaction between macrophages and Paracoccidioides, possibly by blocking the binding sites for FBA. These data reveal the possible participation of the FBA in the processes of cell adhesion and tissue invasion/dissemination of Paracoccidioides. CONCLUSIONS: These data indicate that Paracoccidioides is a pathogen that has several plasminogen-binding proteins that likely play important roles in pathogen-host interaction. In this context, FBA is a protein that might be involved somehow in the processes of invasion and spread of the fungus during infection.


Asunto(s)
Fructosa-Bifosfato Aldolasa/metabolismo , Paracoccidioides/enzimología , Plasminógeno/metabolismo , Fibrina/metabolismo , Fibrinolisina/metabolismo , Fructosa-Bifosfato Aldolasa/genética , Interacciones Huésped-Patógeno , Humanos , Paracoccidioides/genética , Unión Proteica , Proteolisis , Proteómica/métodos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
4.
J Fungi (Basel) ; 10(5)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38786672

RESUMEN

Blood count is crucial for assessing bone marrow's cell production and differentiation during infections, gaging disease severity, and monitoring therapeutic responses. The profile of blood count in chronic forms of paracoccidioidomycosis (PCM) has been insufficiently explored. To better understand the changes in hematological cells in different stages of the PCM chronic form, we evaluated the blood count, including immature blood cells in automated equipment, before and during the treatment follow-up of 62 chronic PCM patients. Predominantly male (96.8%) with an average age of 54.3 (standard deviation SD 6.9) years, participants exhibited pre-treatment conditions such as anemia (45.2%), monocytosis (38.7%), and leukocytosis (17.7%), which became less frequent after clinical cure. Anemia was more prevalent in severe cases. Notably, hemoglobin and reticulocyte hemoglobin content increased, while leukocytes, monocytes, neutrophils, immature granulocytes, and platelets decreased. Chronic PCM induced manageable hematological abnormalities, mainly in the red blood series. Monocytosis, indicating monocytes' role in PCM's immune response, was frequent. Post-treatment, especially after achieving clinical cure, significant improvements were observed in various hematological indices, including immature granulocytes and reticulocyte hemoglobin content, underscoring the impact of infection on these parameters.

5.
PLoS Negl Trop Dis ; 18(9): e0012452, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39226308

RESUMEN

The formamidase (FMD) enzyme plays an important role in fungal thriving by releasing a secondary nitrogen source as a product of its activity. In Paracoccidioides species, previous studies have demonstrated the upregulation of this enzyme in a wide range of starvation and infective-like conditions. However, Paracoccidioides lutzii formamidase has not yet been defined as a virulence factor. Here, by employing in vivo infections using an fmd-silenced strain in Galleria mellonella larvae model, we demonstrate the influence of formamidase in P. lutzii's immune stimulation and pathogenicity. The formamidase silencing resulted in improper arrangement of the nodules, poor melanogenesis and decreased fungal burden. Thus, we suggest that formamidase may be a piece composing the process of molecular recognition by Galleria immune cells. Furthermore, formamidase silencing doubled the observed survival rate of the larvae, demonstrating its importance in fungal virulence in vivo. Therefore, our findings indicate that formamidase contributes to Galleria's immune incitement and establishes the role of this enzyme as a P. lutzii virulence factor.


Asunto(s)
Larva , Mariposas Nocturnas , Paracoccidioides , Factores de Virulencia , Animales , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Larva/microbiología , Mariposas Nocturnas/microbiología , Paracoccidioides/patogenicidad , Paracoccidioides/enzimología , Paracoccidioides/genética , Virulencia , Paracoccidioidomicosis/microbiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Modelos Animales de Enfermedad , Silenciador del Gen
6.
J Fungi (Basel) ; 9(11)2023 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-37998907

RESUMEN

Members of the Paracoccidioides complex are the causative agents of Paracoccidioidomycosis (PCM), a human systemic mycosis endemic in Latin America. Upon initial contact with the host, the pathogen needs to uptake micronutrients. Nitrogen is an essential source for biosynthetic pathways. Adaptation to nutritional stress is a key feature of fungi in host tissues. Fungi utilize nitrogen sources through Nitrogen Catabolite Repression (NCR). NCR ensures the scavenging, uptake and catabolism of alternative nitrogen sources, when preferential ones, such as glutamine or ammonium, are unavailable. The NanoUPLC-MSE proteomic approach was used to investigate the NCR response of Paracoccidioides lutzii after growth on proline or glutamine as a nitrogen source. A total of 338 differentially expressed proteins were identified. P. lutzii demonstrated that gluconeogenesis, ß-oxidation, glyoxylate cycle, adhesin-like proteins, stress response and cell wall remodeling were triggered in NCR-proline conditions. In addition, within macrophages, yeast cells trained under NCR-proline conditions showed an increased ability to survive. In general, this study allows a comprehensive understanding of the NCR response employed by the fungus to overcome nutritional starvation, which in the human host is represented by nutritional immunity. In turn, the pathogen requires rapid adaptation to the changing microenvironment induced by macrophages to achieve successful infection.

7.
PLoS One ; 18(6): e0282218, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37347744

RESUMEN

Paracoccidioidomycosis (PCM) is caused by Paracoccidioides spp.; during infection, some host mechanisms limit the availability of iron, thereby reducing its reproduction. However, Paracoccidioides spp. can evade the immune defense and, even under limited iron conditions, use this mineral for growth and dissemination. This study evaluated the iron metabolism of 39 patients who were diagnosed with chronic PCM from 2013 to 2021. The forms of iron before treatment and at the time of clinical cure were evaluated based on the following: serum ferritin levels (storage iron); total iron-binding capacity (TIBC) and transferrin saturation (TSAT) level (transport iron); red blood cell (RBC), hemoglobin (Hb), hematocrit (HCT), and soluble transferrin receptor (sTfR) levels; and sTfR/log ferritin ratio (functional iron). The mean age of the patients was 54.5 years (±6.7 years). Most patients were men (97.4%), rural workers (92.1%), and smokers (84.6%); furthermore, most had moderate disease severity (66.7%). After achieving clinical cure, we observed that serum ferritin levels decreased, and parameters of functional iron increased. The extent of alteration in these parameters were more pronounced in severe cases than in to mild or moderate cases. Furthermore, moderate correlations were observed between C-reactive protein and the Hb (r = -0.500; p = 0.002), RBC (r = -0.461; p = 0.005), HCT (r = -0.514; p = 0.001), and iron levels (r = -0.491; p = 0.002). However, it is possible to infer that PCM interferes with functional and storage iron because improvements in these parameters after treatment as well as associations with disease severity were observed. PCM can lead to anemia of inflammation, which can be differentiated from iron deficiency anemia by a careful investigation of the iron form parameters.


Asunto(s)
Anemia Ferropénica , Anemia , Trastornos del Metabolismo del Hierro , Paracoccidioidomicosis , Masculino , Humanos , Persona de Mediana Edad , Femenino , Hierro/metabolismo , Ferritinas , Anemia/tratamiento farmacológico , Hemoglobinas/metabolismo , Receptores de Transferrina , Trastornos del Metabolismo del Hierro/tratamiento farmacológico
8.
J Fungi (Basel) ; 9(6)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37367569

RESUMEN

Fungal infections represent a serious global health problem, causing damage to health and the economy on the scale of millions. Although vaccines are the most effective therapeutic approach used to combat infectious agents, at the moment, no fungal vaccine has been approved for use in humans. However, the scientific community has been working hard to overcome this challenge. In this sense, we aim to describe here an update on the development of fungal vaccines and the progress of methodological and experimental immunotherapies against fungal infections. In addition, advances in immunoinformatic tools are described as an important aid by which to overcome the difficulty of achieving success in fungal vaccine development. In silico approaches are great options for the most important and difficult questions regarding the attainment of an efficient fungal vaccine. Here, we suggest how bioinformatic tools could contribute, considering the main challenges, to an effective fungal vaccine.

9.
Pathogens ; 11(5)2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35631090

RESUMEN

Systemic mycoses have been viewed as neglected diseases and they are responsible for deaths and disabilities around the world. Rapid, low-cost, simple, highly-specific and sensitive diagnostic tests are critical components of patient care, disease control and active surveillance. However, the diagnosis of fungal infections represents a great challenge because of the decline in the expertise needed for identifying fungi, and a reduced number of instruments and assays specific to fungal identification. Unfortunately, time of diagnosis is one of the most important risk factors for mortality rates from many of the systemic mycoses. In addition, phenotypic and biochemical identification methods are often time-consuming, which has created an increasing demand for new methods of fungal identification. In this review, we discuss the current context of the diagnosis of the main systemic mycoses and propose alternative approaches for the identification of new targets for fungal pathogens, which can help in the development of new diagnostic tests.

10.
Microorganisms ; 10(10)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36296287

RESUMEN

Nitrogen is a crucial nutrient for microorganisms that compose essential biomolecules. However, hosts limit this nutrient as a strategy to counter infections, therefore, pathogens use adaptive mechanisms to uptake nitrogen from alternative sources. In fungi, nitrogen catabolite repression (NCR) activates transcription factors to acquire nitrogen from alternative sources when preferential sources are absent. Formamidase has been related to nitrogen depletion in Aspergillus nidulans through formamide degradation to use the released ammonia as a nitrogen source. In Paracoccidioides spp., formamidase is highly expressed in transcriptomic and proteomic analyses. Here, we aim to investigate the importance of formamidase to Paracoccidioides lutzii. Thereby, we developed a P. lutzii silenced strain of fmd gene (AsFmd) by antisense RNA technology using Agrobacterium tumefaciens-mediated transformation (ATMT). The AsFmd strain led to increased urease expression, an enzyme related to nitrogen assimilation in other fungi, suggesting that P. lutzii might explore urease as an alternative route for ammonia metabolism as a nitrogen source. Moreover, formamidase was important for fungal survival inside macrophages, as fungal recovery after macrophage infection was lower in AsFmd compared to wild-type (WT) strain. Our findings suggest potential alternatives of nitrogen acquisition regulation in P. lutzii, evidencing formamidase influence in fungal virulence.

11.
PLoS Negl Trop Dis ; 15(4): e0009317, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33826630

RESUMEN

BACKGROUND: Paracoccidioidomycosis (PCM) is a systemic and endemic fungal infection in Latin American, mainly in Brazil. The majority of PCM cases occur in large areas in Brazil, comprising the South, Southeast and Midwest regions, with the latter demonstrating a higher incidence of the species Paracoccidioides lutzii. METHODOLOGY AND MAIN FINDINGS: This study presents clinical, molecular and serological data of thirteen new PCM cases during 2016 to 2019 from the state of Mato Grosso do Sul, located in the Midwest region, Brazil. From these thirteen cases, sixteen clinical isolates were obtained and their genomic DNAs were subjected to genotyping by tub1 -PCR-RFLP. Results showed Paracoccidioides brasiliensis sensu stricto (S1) (11/16; 68.8%), Paracoccidioides restrepiensis (PS3) (4/16; 25.0%) and P. lutzii (1/16; 6.2%) as Paracoccidiodes species. Therefore, in order to understand whether the type of phylogenetic species that are circulating in the state influence the reactivity profile of serological tests, we performed double agar gel immunodiffusion (DID), using exoantigens from genotyped strains found in this series of PCM cases. Overall, our DID tests have been false negative in about 30% of confirmed PCM cases. All patients were male, most with current or previous rural activity, with ages ranging from 17 to 59 years, with 11 patients (84.6%) over 40 years of age. No clinical or epidemiological differences were found between Paracoccidioides species. However, it is important to note that the only case of P. lutzii died as an outcome. CONCLUSIONS: This study suggests P. brasiliensis sensu stricto (S1) as the predominant species, showing its wide geographic distribution in Brazil. Furthermore, our findings revealed, for the first time, the occurrence of P. restrepiensis (PS3) in the state of Mato Grosso do Sul, Brazil. Despite our setbacks, it would be interesting to provide the complete sequencing of these clinical isolates to complement the molecular information presented.


Asunto(s)
Antígenos Fúngicos/inmunología , Paracoccidioides/inmunología , Paracoccidioidomicosis/inmunología , Paracoccidioidomicosis/microbiología , Adolescente , Adulto , Anticuerpos Antifúngicos/inmunología , Brasil/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Paracoccidioides/clasificación , Paracoccidioides/aislamiento & purificación , Paracoccidioidomicosis/diagnóstico , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Serotipificación , Adulto Joven
12.
J Med Food ; 24(3): 273-281, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32543997

RESUMEN

Flavonoids-compounds abundant in balanced daily diets-have been extensively investigated for biological activity. The pronounced antiproliferative effects of flavonoids have prompted studies to elucidate their mode of action against tumor cells. The anticancer properties of myricetin, a 3',4',5'-tri-hydroxylated flavonol, have been confirmed for a number of neoplasms, but myricitrin, its 3-O-rhamnoside derivative found in fruits and other parts of edible plants, has been scarcely investigated as a chemopreventive agent. This study evaluated the antiproliferative potential of myricitrin obtained from Combretum lanceolatum (Combretaceae) against MCF7 (breast), PC-3 (prostate), HT-29 (colon), 786-0 (kidney), and HL-60 (acute promyelocytic leukemia) cancer cell lines, using the sulforhodamine B and tetrazolium salt assays. Myricitrin proved most effective in inhibiting growth of HL-60 cells (GI50 = 53.4 µmol·L-1), yet showed weak antiproliferative activity against other cell lines. Possible cytotoxic mechanisms involving inhibition of topoisomerases I and IIα by myricitrin were also evaluated, revealing inhibitory activity only against topoisomerase IIα. The results suggested that topoisomerase IIα inhibition is the probable mechanism responsible for the antiproliferative activity of myricitrin. In vivo mutagenicity by myricitrin and its possible antimutagenic effect on doxorubicin-induced DNA damage were also investigated by performing the somatic mutation and recombination test (SMART) on Drosophila melanogaster. Myricitrin proved nonmutagenic to the offspring of standard (ST) and high-bioactivation (HB) crosses, while cotreatments with doxorubicin revealed the antimutagenic properties of myricitrin, even under conditions of high metabolic activation.


Asunto(s)
Combretum , Animales , Línea Celular Tumoral , Doxorrubicina , Drosophila melanogaster , Flavonoides/farmacología , Mutágenos/toxicidad
13.
Biomed Pharmacother ; 144: 112198, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34656058

RESUMEN

Erythrina poeppigiana belongs to Fabaceae family (subfamily Papillionoideae) and is commonly found in tropical and subtropical regions in Brazil. Herein, we described the purification and characterization of a new Kunitz-type inhibitor, obtained from E. poeppigiana seeds (EpTI). EpTI is composed by three isoforms of identical amino-terminal sequences with a molecular weight ranging from 17 to 20 kDa. The physicochemical features showed by EpTI are common to Kunitz inhibitors, including the dissociation constant (13.1 nM), stability against thermal (37-100 °C) and pH (2-10) ranging, and the presence of disulfide bonds stabilizing its reactive site. Furthermore, we investigated the antimicrobial, anti-adhesion, and anti-biofilm properties of EpTI against Gram-positive and negative bacteria. The inhibitor showed antimicrobial activity with a minimum inhibitory concentration (MIC, 5-10 µM) and minimum bactericidal concentration (MBC) of 10 µM for Enterobacter aerogenes, Enterobacter cloacae, Klebsiella pneumoniae, Staphylococcus aureus, and Staphylococcus haemolyticus. The combination of EpTI with ciprofloxacin showed a marked synergistic effect, reducing the antibiotic concentration by 150%. The increase in crystal violet uptake for S. aureus and K. pneumoniae strains was approximately 30% and 50%, respectively, suggesting that the bacteria plasma membrane is targeted by EpTI. Treatment with EpTI at 1x and 10 x MIC significantly reduced the biofilm formation and prompted the disruption of a mature biofilm. At MIC/2, EpTI decreased the bacterial adhesion to polystyrene surface within 2 h. Finally, EpTI showed low toxicity in animal model Galleria mellonella. Given its antimicrobial and anti-biofilm properties, the EpTI sequence might be used to design novel drug prototypes.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Erythrina , Extractos Vegetales/farmacología , Inhibidores de Tripsina/farmacología , Animales , Antibacterianos/aislamiento & purificación , Antibacterianos/toxicidad , Bacterias/crecimiento & desarrollo , Biopelículas/crecimiento & desarrollo , Ciprofloxacina/farmacología , Sinergismo Farmacológico , Erythrina/química , Pruebas de Sensibilidad Microbiana , Mariposas Nocturnas/efectos de los fármacos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Semillas , Inhibidores de Tripsina/aislamiento & purificación , Inhibidores de Tripsina/toxicidad
14.
Hematol Transfus Cell Ther ; 42(3): 230-237, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31519529

RESUMEN

BACKGROUND: Thrombocytopenia (TP) is the major event associated with linezolid (LZD) therapy. We investigated the incidence and risk factors for thrombocytopenia in hospitalized adults who received LZD (1200mg/day) between 2015 and 2017. HIV-positive, death during follow-up and those with a baseline platelet count ≤100×103/mm3 were excluded. METHOD: TP was defined as a decrease in platelet count of ≥20% from the baseline level at the initiation of linezolid therapy and a final count of <100×103/mm3. The odds ratios (OR) for thrombocytopenia were obtained using multivariate stepwise logistic regression analysis. MAIN RESULTS: A total of 66 patients were included (mean age [SD] 62 [18], male gender [%], 37 [56]). LZD-associated TP was identified in 12 patients (18.2%). For TP, the adjusted OR [95% CI] of the platelet count ≤200×103/mm3, serum creatinine and renal impairment at baseline were 5.66 [1.15-27.9], 4.57 [1.26-16.5] and 9.41 [1.09-80.54], respectively. Male gender and dosage per weight per day (DPWD) >20mg/kg/day were not risk factors. CONCLUSION: The results showed that the incidence of linezolid-induced thrombocytopenia was lower in patients with normal renal function and higher in those with platelet counts ≤200×103/mm3 or serum creatinine >1.5mg/dL at the start of the treatment.

15.
Rev Soc Bras Med Trop ; 52: e20180001, 2019 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-30785531

RESUMEN

INTRODUCTION: Studies have demonstrated that pathogens react to the harsh conditions in human tissues by inducing mechanisms that promote survival. METHODS: Persistence and biofilm-forming ability were evaluated during stress conditions that mimic those in the host. RESULTS: Carbon-source availability had a positive effect on Staphylococcus epidermidis RP62A adhesion during hypoxia, accompanied by a decrease in pH. In contrast, iron limitation led to decreased surface-adherent biomass, accompanied by an increase medium acidification and lactate levels. Interestingly, iron starvation and hypoxia induced persister cells in planktonic culture. CONCLUSIONS: These findings highlight the role of host stress in the virulence of S. epidermidis.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Medios de Cultivo/farmacología , Interacciones Microbiota-Huesped/fisiología , Staphylococcus epidermidis/fisiología , Virulencia/fisiología , Bioensayo , Interacciones Microbiota-Huesped/efectos de los fármacos , Humanos , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/patogenicidad , Estrés Fisiológico , Virulencia/efectos de los fármacos
16.
Front Microbiol ; 10: 2968, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32117076

RESUMEN

Fungi of the Paracoccidioides genus are the etiological agents of paracoccidioidomycosis (PCM), a systemic mycosis restricted to the countries of Latin America. Currently, the Paracoccidioides complex is represented by Paracoccidioides lutzii, Paracoccidioides americana, Paracoccidioides brasiliensis, Paracoccidioides restrepiensis, and Paracoccidioides venezuelensis. Even with advances in techniques used for diagnosing fungal diseases, high rates of false-positive results for PCM are still presented. Additionally, there is no efficient antigen that can be used to follow up the efficiency of patient treatment. The immunoproteomic is considered a powerful tool for the identification of antigens. In addition, antigens are molecules recognized by the immune system, which make them excellent targets for diagnostic testing of diseases caused by microorganisms. In this vein, we investigated which antigens are secreted by species representing Paracoccidioides complex to increase the spectrum of molecules that could be used for future diagnostic tests, patient follow-up, or PCM therapy. To identify the profile of antigens secreted by Paracoccidioides spp., immunoproteomic approaches were used combining immunoprecipitation, followed by antigen identification by nanoUPLC-MSE-based proteomics. Consequently, it was possible to verify differences in the exoantigen profiles present among the studied species. Through a mass spectrometry approach, it was possible to identify 79 exoantigens in Paracoccidioides species. Using bioinformatics tools, two unique exoantigens in P. lutzii species were identified, as well as 44 epitopes exclusive to the Paracoccidioides complex and 12 unique antigenic sequences that can differentiate between Paracoccidioides species. Therefore, these results demonstrate that Paracoccidioides species have a range of B-cell epitopes exclusive to the complex as well as specific to each Paracoccidioides species. In addition, these analyses allowed us the identification of excellent biomarker candidates for epidemiology screening, diagnosis, patient follow-up, as well as new candidates for PCM therapy.

17.
PLoS One ; 13(10): e0206051, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30359420

RESUMEN

Paracoccidioidomycosis (PCM) is a systemic disease caused by thermodymorphic fungi of the Paracoccidioides brasiliensis complex, (Paracoccidioides spp.). Patients with PCM reveal specific cellular immune impairment. Despite the effective treatment, quiescent fungi can lead to relapse, usually late, the serological diagnosis of which has been deficient. The present study was carried out with the objective of investigating a biomarker for the identification of PCM relapse and another molecule behaving as an immunological recovery biomarker; therefore, it may be used as a cure criterion. In the evolutionary analysis of the proteins identified in PCM patients, comparing those that presented with those that did not reveal relapse, 29 proteins were identified. The interactions observed between the proteins, using transferrin and haptoglobin, as the main binding protein, were strong with all the others. Patient follow-up suggests that cerulosplamin may be a marker of relapse and that transferrin and apolipoprotein A-II may contribute to the evaluation of the treatment efficacy and avoiding a premature decision.


Asunto(s)
Apolipoproteína A-II/sangre , Ceruloplasmina/metabolismo , Paracoccidioidomicosis/sangre , Transferrina/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Mapas de Interacción de Proteínas , Recurrencia , Resultado del Tratamiento , Adulto Joven
18.
Fungal Biol ; 122(8): 738-751, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30007425

RESUMEN

Paracoccidioides is a thermodimorphic fungus that causes Paracoccidioidomycosis (PCM) - an endemic systemic mycosis in Latin America. The genus comprises several phylogenetic species which present some genetic and serological differences. The diversity presented among isolates of the same genus has been explored in several microorganisms. There have also been attempts to clarify differences that might be related to virulence existing in isolates that cause the same disease. In this work, we analyzed the secretome of two isolates in the Paracoccidioides genus, isolates Pb01 and PbEpm83, and performed infection assays in macrophages to evaluate the influence of the secretomes of those isolates upon an in vitro model of infection. The use of a label-free proteomics approach (LC-MSE) allowed us to identify 92 proteins that are secreted by those strains. Of those proteins, 35 were differentially secreted in Pb01, and 36 in PbEpm83. According to the functional annotation, most of the identified proteins are related to adhesion and virulence processes. These results provide evidence that different members of the Paracoccidioides complex can quantitatively secrete different proteins, which may influence the characteristics of virulence, as well as host-related processes.


Asunto(s)
Proteínas Fúngicas/análisis , Paracoccidioides/química , Proteoma/análisis , Animales , Línea Celular , Cromatografía Liquida , América Latina , Macrófagos/microbiología , Espectrometría de Masas , Ratones , Modelos Biológicos , Paracoccidioides/crecimiento & desarrollo , Paracoccidioides/aislamiento & purificación , Paracoccidioidomicosis/microbiología , Factores de Virulencia/análisis
19.
PLoS One ; 13(8): e0202804, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30157221

RESUMEN

The sensitivity of the double agar gel immunodiffusion test is about 90% in patients with untreated paracoccidioidomycosis (PCM), but it is much lower in cases of relapse. In addition, serum from patients with PCM caused by Paracoccidioides lutzii, frequent in the Midwest region of Brazil, do not react with the classical antigen obtained from Pb B-339. These findings showed the need for alternative diagnostic methods, such as biological markers through proteomics. The aim of this study was to identify biomarkers for the safe identification of PCM relapse and specific proteins that could distinguish infections caused by Paracoccidioides brasiliensis from those produced by Paracoccidioides lutzii. Proteomic analysis was performed in serum from 9 patients with PCM caused by P. brasiliensis, with and without relapse, from 4 patients with PCM produced by P. lutzii, and from 3 healthy controls. The comparative evaluation of the 29 identified plasma proteins suggested that the presence of the immunoglobulin (Ig) alpha-2 chain C region and the absence of Ig heavy chain V-III TIL indicate infection by P. lutzii. In addition, the absence of complement factor B protein might be a predictor of relapse. The evaluation of these proteins in a higher number of patients should be carried out in order to validate these findings.


Asunto(s)
Biomarcadores/sangre , Paracoccidioides/metabolismo , Paracoccidioidomicosis/diagnóstico , Proteómica , Adolescente , Adulto , Anciano de 80 o más Años , Anticuerpos Antifúngicos/química , Anticuerpos Antifúngicos/inmunología , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión , Femenino , Proteínas Fúngicas/análisis , Proteínas Fúngicas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Paracoccidioides/aislamiento & purificación , Paracoccidioidomicosis/microbiología , Recurrencia , Riesgo , Espectrometría de Masas en Tándem
20.
PLoS One ; 13(4): e0195678, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29634766

RESUMEN

The anti-inflammatory, antiproliferative and cytoprotective activity of the Attalea phalerata Mart. ex Spreng pulp oil was evaluated by in vitro and in vivo methods. As for the chemical profile, the antioxidant activity was performed by spectrophotometry, and the profile of carotenoids and amino acids by chromatography. Our data demonstrated that A. phalerata oil has high carotenoid content, antioxidant activity and the presence of 5 essential amino acids. In the in vitro models of inflammation, the oil demonstrated the capacity to inhibit COX1 and COX2 enzymes, the production of nitric oxide and also induces macrophages to spreading. In the in vivo models of inflammation, the oil inhibited edema and leukocyte migration in the Wistar rats. In the in vitro model of antiproliferative and cytoprotective activity, the oil was shown inactive against the kidney carcinoma and prostate carcinoma lineage cells and with cytoprotective capacity in murine fibroblast cells, inhibiting the cytotoxic action of doxorubicin. Therefore, it is concluded that A. phalerata pulp oil has anti-inflammatory effects with nutraceutical properties potential due to the rich composition. Moreover, the oil also has cytoprotective activity probably because of its ability to inhibit the action of free radicals.


Asunto(s)
Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Arecaceae/química , Citoprotección/efectos de los fármacos , Aceites de Plantas/farmacología , Aminoácidos/análisis , Animales , Antiinflamatorios/química , Antineoplásicos/química , Carotenoides/análisis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Masculino , Ratones , Aceites de Plantas/química , Ratas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA