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1.
Nat Commun ; 15(1): 3190, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609393

RESUMEN

Coccidioidomycosis, listed as a priority mycosis by the WHO, is endemic in the United States but often overlooked in Central and South America. Employing a multi-institutional approach, we investigate how disease characteristics, pathogen genetic variation, and environmental factors impact coccidioidomycosis epidemiology and outcomes in South America. We identified 292 cases (1978-2021) and 42 outbreaks in Piauí and Maranhão states, Brazil, the largest series outside the US/Mexico epidemic zone. The male-to-female ratio was 57.4:1 and the most common activity was armadillo hunting (91.1%) 4 to 30 days before symptom onset. Most patients (92.8%) exhibited typical acute pulmonary disease, with cough (93%), fever (90%), and chest pain (77%) as predominant symptoms. The case fatality rate was 8%. Our negative binomial regression model indicates that reduced precipitation levels in the current (p = 0.015) and preceding year (p = 0.001) predict heightened incidence. Unlike other hotspots, acidic soil characterizes this region. Brazilian strains differ genomically from other C. posadasii lineages. Northeastern Brazil presents a distinctive coccidioidomycosis profile, with armadillo hunters facing elevated risks. Low annual rainfall emerges as a key factor in increasing cases. A unique C. posadasii lineage in Brazil suggests potential differences in environmental, virulence, and/or pathogenesis traits compared to other Coccidioides genotypes.


Asunto(s)
Coccidioidomicosis , Humanos , Femenino , Masculino , Animales , Brasil/epidemiología , Coccidioidomicosis/epidemiología , Armadillos , Genómica , Genotipo
2.
Arq. Asma, Alerg. Imunol ; 7(1): 23-40, 20230300. ilus
Artículo en Inglés, Portugués | LILACS | ID: biblio-1509599

RESUMEN

Este trabalho objetiva caracterizar a assistência ofertada às crianças com alergia ao leite em programas públicos, e os desafios enfrentados na sua implantação, no contexto da pré-incorporação no Sistema Único de Saúde, de três fórmulas infantis para alergia ao leite. Estudo exploratório, transversal e abordagem quantitativa. Foram avaliados 21 programas/serviços de todas as regiões brasileiras. O principal indutor da criação destes programas foi a judicialização (80,9%), e o fornecimento destas fórmulas especiais foi realizado para crianças com até 2 anos de idade. Os principais desafios para a criação e execução destes programas foram a falta de recursos humanos e financeiros, a falta da contrapartida da União, protocolo unificado para o diagnóstico (Teste de Provocação Oral), e a escolha dos tipos das fórmulas. A estratégia mais adotada para redução dos custos foi a adequação das normas e protocolos (61,9%). Não houve diferença significativa entre os programas estaduais e municipais. Este estudo apresenta uma avaliação inédita e detalhada sobre os programas, trazendo discussões que corroboram a tomada de decisões, o uso racional de recursos públicos, a melhor assistência às crianças e o fortalecimento do sistema de saúde nacional.


This paper aims to characterize the assistance offered to children with cow's milk allergy in public programs and challenges to their implementation, specifically assessing the pre-incorporation phase in the Brazilian Unified Health System of 3 formulas for infants with milk allergy. This exploratory, cross-sectional study with a quantitative approach assessed 21 programs/services from all regions of the country. The main motivation for the creation of these programs was judicialization (80.9%), and these special formulas were provided for children up to 2 years of age. The main challenges to creating and implementing these programs were a lack of human and financial resources, no counterpart federal program, no unified protocol for diagnosis (oral provocation test), and the selection of formula types. The most common strategy for reducing costs was updating norms and protocols (61.9%), which did not differ significantly between state and municipal programs. This study presents an unprecedented and detailed evaluation of the programs, raising discussion about decision-making, the rational use of public resources, better care for children, and means of strengthening of the national health system.


Asunto(s)
Humanos , Recién Nacido , Lactante , Preescolar , Brasil
3.
J Fungi (Basel) ; 9(2)2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36836338

RESUMEN

Chromoblastomycosis (CBM) is a disease caused by several dematiaceous fungi from different genera, and Fonsecaea is the most common which has been clinically isolated. Genetic transformation methods have recently been described; however, molecular tools for the functional study of genes have been scarcely reported for those fungi. In this work, we demonstrated that gene deletion and generation of the null mutant by homologous recombination are achievable for Fonsecaea pedrosoi by the use of two approaches: use of double-joint PCR for cassette construction, followed by delivery of the split-marker by biolistic transformation. Through in silico analyses, we identified that F. pedrosoi presents the complete enzymatic apparatus required for tryptophan (trp) biosynthesis. The gene encoding a tryptophan synthase trpB -which converts chorismate to trp-was disrupted. The ΔtrpB auxotrophic mutant can grow with external trp supply, but germination, viability of conidia, and radial growth are defective compared to the wild-type and reconstituted strains. The use of 5-FAA for selection of trp- phenotypes and for counter-selection of strains carrying the trp gene was also demonstrated. The molecular tools for the functional study of genes, allied to the genetic information from genomic databases, significantly boost our understanding of the biology and pathogenicity of CBM causative agents.

4.
Preprint en Portugués | SciELO Preprints | ID: pps-4710

RESUMEN

The objective of this article is to characterize the assistance offered to children with milk allergies in public programs and the challenges faced in its implementation, in the context of the pre-incorporation in the Unified Health System of three infant formulas for milk allergy. Exploratory, cross-sectional study and quantitative approach. Twenty-one programs and/or services were evaluated (15 municipal and 6 states) from all Brazilian regions. The main driver of the creation of these programs was judicialization (80.9%) and the provision of these special formulas was carried out to children up to 2 years of age. Among the main difficulties in creating and executing these programs, the lack of human and financial resources was the most common reason, representing 71.4% and 61.9%, respectively. The most adopted strategy to reduce costs was the adequacy of norms and protocols (61.9%). There was no significant difference between state and municipal programs. This study presents an unprecedented and detailed evaluation of the programs, bringing discussions that support decision-making, rational use of public resources, better care for children and strengthening of the national health system. Key words: Unified Health System. Program Evaluation. Continuity of Patient Care. Milk Hypersensitivity. Health Manager.


Objetiva-se neste artigo caracterizar a assistência ofertada às crianças com alergia ao leite em programas públicos e os desafios enfrentados na sua implantação, no contexto da pré-incorporação no Sistema Único de Saúde de três fórmulas infantis para alergia ao leite. Estudo exploratório, transversal e abordagem quantitativa. Foram avaliados 21 programas e/ou serviços (15 municipais e 6 estaduais) de todas as regiões brasileiras. O principal indutor da criação destes programas foi a judicialização (80,9%) e o fornecimento destas fórmulas especiais era realizado às crianças com até 2 anos de idade. Dentre as principais dificuldades para criação e execução destes programas, a falta de recursos humanos e financeiros foram as razões mais presentes, representando 71,4% e 61,9%, respectivamente. A estratégia mais adotada para redução dos custos foi a adequação das normas e protocolos (61,9%). Não houve diferença significativa entre os programas estaduais e municipais. Este estudo apresenta uma avaliação inédita e detalhada sobre os programas trazendo discussões que corroboram na tomada de decisões, uso racional de recursos públicos, melhor assistência às crianças e fortalecimento do sistema de saúde nacional. Palavras-Chave: Sistema Único de Saúde. Avaliação de Programas e Projetos de Saúde. Continuidade da Assistência ao Paciente. Hipersensibilidade a Leite. Gestor de Saúde.

5.
J Fungi (Basel) ; 8(4)2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35448624

RESUMEN

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

6.
Immunology ; 165(1): 110-121, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34458991

RESUMEN

Decades of studies on antibody structure led to the tenet that the V region binds antigens while the C region interacts with immune effectors. In some antibodies, however, the C region affects affinity and/or specificity for the antigen. One example is the 3E5 monoclonal murine IgG family, in which the mIgG3 isotype has different fine specificity to the Cryptococcus neoformans capsule polysaccharide than the other mIgG isotypes despite their identical variable sequences. Our group serendipitously found another pair of mIgG1/mIgG3 antibodies based on the 2H1 hybridoma to the C. neoformans capsule that recapitulated the differences observed with 3E5. In this work, we report the molecular basis of the constant domain effects on antigen binding using recombinant antibodies. As with 3E5, immunofluorescence experiments show a punctate pattern for 2H1-mIgG3 and an annular pattern for 2H1-mIgG1; these binding patterns have been associated with protective efficacy in murine cryptococcosis. Also as observed with 3E5, 2H1-mIgG3 bound on ELISA to both acetylated and non-acetylated capsular polysaccharide, whereas 2H1-mIgG1 only bound well to the acetylated form, consistent with differences in fine specificity. In engineering hybrid mIgG1/mIgG3 antibodies, we found that switching the 2H1-mIgG3 hinge for its mIgG1 counterpart changed the immunofluorescence pattern to annular, but a 2H1-mIgG1 antibody with an mIgG3 hinge still had an annular pattern. The hinge is thus necessary but not sufficient for these changes in binding to the antigen. This important role for the constant region in antigen binding could affect antibody biology and engineering.


Asunto(s)
Antígenos Bacterianos/química , Antígenos Bacterianos/inmunología , Cápsulas Bacterianas/química , Cápsulas Bacterianas/inmunología , Cryptococcus neoformans/inmunología , Inmunoglobulina G/química , Inmunoglobulina G/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Sitios de Unión de Anticuerpos , Células CHO , Línea Celular , Cricetulus , Criptococosis/inmunología , Epítopos/química , Epítopos/inmunología , Ratones , Proteínas Recombinantes de Fusión , Relación Estructura-Actividad
7.
PLoS Negl Trop Dis ; 15(11): e0009956, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34843484

RESUMEN

INTRODUCTION: Paracoccidioidomycosis (PCM) is caused by several species of the Paracoccidioides genus which can be differentiated by interspecific genetic variations, morphology and geographic distribution. Intraspecific variability correlation with clinical and epidemiological aspects of these species still remains unclear. This study aimed to sequence the loci GP43, exon 2 and ARF of 23 clinical isolates of Paracoccidioides spp. from patients in the Southeast Region of Brazil. METHODOLOGY AND MAIN FINDINGS: GenBank was used to compare the present (23) with previous described sequences (151) that included ARF and GP43. It was identified a high polymorphism rate among the 23 isolates in comparison to the other 151. Among the isolates, 22 (95.66%) were S1/P. brasiliensis and 1 (4.34%) was identified as PS2/P. americana. A total of 45 haplotypes were found as follows: 19 from S1/P. brasiliensis (13 from the present study), 15 from P. lutzii, 6 from PS2/P. americana (1 from the present study), 3 from PS3/P. restrepiensis and 2 from PS4/P. venezuelensis. Moreover, exclusive haplotypes according to clinical origin and geographical area were found. S1/P. brasiliensis (HD = 0.655 and K = 4.613) and P. lutzii (HD = 0.649 and K = 2.906) presented the highest rate of polymorphism among all species, from which 12 isolates of the present study were clustered within S1b/P. brasiliensis. The GP43 locus showed a higher variability and was found to be the main reason for the species differentiation. CONCLUSIONS: The results herein decribed show a high intraspecific genetic variability among S1/P. brasiliensis isolates and confirm the predominance of this species in the Southeast region of Brazil. The finding of exclusive haplotypes according to clinical origin and geographical area would suggest correlation between the molecular profile with the clinical form and geographic origin of patients with PCM.


Asunto(s)
Paracoccidioides/genética , Paracoccidioidomicosis/microbiología , Adolescente , Adulto , Brasil/epidemiología , Niño , Preescolar , Femenino , Variación Genética , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Paracoccidioides/clasificación , Paracoccidioides/aislamiento & purificación , Paracoccidioidomicosis/epidemiología , Filogenia , Adulto Joven
8.
Sci Rep ; 11(1): 15185, 2021 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-34312413

RESUMEN

Parkinson's disease (PD) is a progressive and chronic neurodegenerative disease of the central nervous system. Early treatment for PD is efficient; however, long-term systemic medication commonly leads to deleterious side-effects. Strategies that enable more selective drug delivery to the brain using smaller dosages, while crossing the complex brain-blood barrier (BBB), are highly desirable to ensure treatment efficacy and decrease/avoid unwanted outcomes. Our goal was to design and test the neurotherapeutic potential of a forefront nanoparticle-based technology composed of albumin/PLGA nanosystems loaded with dopamine (ALNP-DA) in 6-OHDA PD mice model. ALNP-DA effectively crossed the BBB, replenishing dopamine at the nigrostriatal pathway, resulting in significant motor symptom improvement when compared to Lesioned and L-DOPA groups. Notably, ALNP-DA (20 mg/animal dose) additionally up-regulated and restored motor coordination, balance, and sensorimotor performance to non-lesioned (Sham) animal level. Overall, ALNPs represent an innovative, non-invasive nano-therapeutical strategy for PD, considering its efficacy to circumvent the BBB and ultimately deliver the drug of interest to the brain.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Dopamina/administración & dosificación , Dopamina/farmacocinética , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/efectos de los fármacos , Humanos , Masculino , Ratones , Nanopartículas/química , Nanopartículas/ultraestructura , Nanotecnología , Oxidopamina/toxicidad , Trastornos Parkinsonianos/inducido químicamente , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química
9.
Pathogens ; 10(3)2021 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-33800117

RESUMEN

Candida albicans is the most common species isolated from nosocomial bloodstream infections. Due to limited therapeutic arsenal and increase of drug resistance, there is an urgent need for new antifungals. Therefore, the antifungal activity against C. albicans and in vivo toxicity of a 1,3,4-oxadiazole compound (LMM6) was evaluated. This compound was selected by in silico approach based on chemical similarity. LMM6 was highly effective against several clinical C. albicans isolates, with minimum inhibitory concentration values ranging from 8 to 32 µg/mL. This compound also showed synergic effect with amphotericin B and caspofungin. In addition, quantitative assay showed that LMM6 exhibited a fungicidal profile and a promising anti-biofilm activity, pointing to its therapeutic potential. The evaluation of acute toxicity indicated that LMM6 is safe for preclinical trials. No mortality and no alterations in the investigated parameters were observed. In addition, no substantial alteration was found in Hippocratic screening, biochemical or hematological analyzes. LMM6 (5 mg/kg twice a day) was able to reduce both spleen and kidneys fungal burden and further, promoted the suppresses of inflammatory cytokines, resulting in infection control. These preclinical findings support future application of LMM6 as potential antifungal in the treatment of invasive candidiasis.

10.
Clin Ther ; 43(5): e103-e138, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33892966

RESUMEN

PURPOSE: The field of human medicine is in a constant state of evolution, developing and incorporating technological advances from diverse scientific fields. In recent years, cellular and gene therapies have come of age, challenging regulatory agencies to define the path for commercial registration. Approval necessarily demands robust evidence for safety and efficacy, but these exigencies must not be such that they render unviable the development and testing of the therapeutic agent. Furthermore, reimbursement strategies are required to guarantee commercial viability of these products, to avoid the risk that they will be removed from the market or become unavailable to most patients through lack of financial resources. To address such challenges, several countries have created strategies to manage advanced therapy products. METHODS: Based on official documents published by regulatory agencies worldwide, this review summarizes the current scenario in the United States, Europe, Brazil, Japan, South Korea, and China in this regard, discussing the harmonized and dissonant aspects of the regulatory framework in different regions of the world and exploring perspectives for the future. FINDINGS: The technical aspects of advanced therapies are increasingly complex, bringing challenges for high mass commercialization and demanding specific regulation. The regulatory framework of the analyzed regions is mainly recent and discordant, but many harmonizing initiatives were observed. IMPLICATIONS: The comparative analysis of regulatory frameworks in different parts of the world is informative, as scientists must be aware of the rationale of regulators to assertively develop new technology and products that will be commercialized. The comparative analysis also provides insight into the main dissonances that must be addressed, fostering the harmonization of local regulatory frameworks. Many unanswered questions still lie ahead for the field of advanced therapies, and empirical evidence will be the most effective way to separate hype from hope and to establish the most sustainable mechanisms to regulate and finance such products in each part of the world.


Asunto(s)
Terapia Genética , Agencias Gubernamentales , China , Europa (Continente) , Predicción , Humanos , Estados Unidos
11.
Emerg Microbes Infect ; 9(1): 2515-2525, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33155518

RESUMEN

Sporotrichosis is a subcutaneous infection caused by fungi from the genus Sporothrix. It is transmitted by inoculation of infective particles found in plant-contaminated material or diseased animals, characterizing the classic sapronotic and emerging zoonotic transmission, respectively. Since 1998, southeastern Brazil has experienced a zoonotic sporotrichosis epidemic caused by S. brasiliensis, centred in the state of Rio de Janeiro. Our observation of feline sporotrichosis cases in Brasília (Midwestern Brazil), around 900 km away from Rio de Janeiro, led us to question whether the epidemic caused by S. brasiliensis has spread from the epicentre in Rio de Janeiro, emerged independently in the two locations, or if the disease has been present and unrecognized in Midwestern Brazil. A retrospective analysis of 91 human and 4 animal cases from Brasília, ranging from 1993 to 2018, suggests the occurrence of both sapronotic and zoonotic transmission. Molecular typing of the calmodulin locus identified S. schenckii as the agent in two animals and all seven human patients from which we were able to recover clinical isolates. In two other animals, the disease was caused by S. brasiliensis. Whole-genome sequence typing of seven Sporothrix spp. strains from Brasília and Rio de Janeiro suggests that S. brasiliensis isolates from Brasília are genetically distinct from those obtained at the epicentre of the outbreak in Rio de Janeiro, both in phylogenomic and population genomic analyses. The two S. brasiliensis populations seem to have separated between 2.2 and 3.1 million years ago, indicating independent outbreaks or that the zoonotic S. brasiliensis outbreak might have started earlier and be more widespread in South America than previously recognized.


Asunto(s)
Calmodulina/genética , Sporothrix/clasificación , Esporotricosis/epidemiología , Secuenciación Completa del Genoma/métodos , Zoonosis/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Brasil/epidemiología , Gatos , Niño , Preescolar , Estudios Transversales , Perros , Evolución Molecular , Femenino , Genoma Fúngico , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Masculino , Persona de Mediana Edad , Tipificación Molecular , Filogenia , Sporothrix/genética , Sporothrix/aislamiento & purificación , Esporotricosis/microbiología , Adulto Joven , Zoonosis/epidemiología
12.
J Fungi (Basel) ; 6(4)2020 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-32998395

RESUMEN

Paracoccidioidomycosis (PCM) is one of the most frequent systemic mycoses in Latin America. It affects mainly male rural workers in impoverished regions, and the therapy can last up to two years or use drugs that are very toxic. Given the need for novel safe and effective approaches to treat PCM, we have been developing monoclonal antibodies (mAbs) that could be used not only to block specific fungal targets, but also modulate the host's antifungal immunity. In this work we show the generation of and promising results with an mAb against Heat Shock Protein (HSP)90, a molecular chaperone that is an important virulence factor in fungi. Using recombinant Paracoccidioides lutzii (Pb01) and P. brasiliensis (Pb18) HSP90 proteins produced in E. coli, we immunized mice and generated polyclonal antibodies and an IgG1 hybridoma mAb. The proteins were very immunogenic and both the polyclonal serum and mAb were used in immunofluorescence experiments, which showed binding of antibodies to the yeast cell surface. The mAb successfully opsonized P. lutzii and P. brasiliensis cells in co-incubations with J774.16 macrophage-like cells. Our results suggest that this mAb could serve as the basis for new immunotherapy regimens for PCM.

13.
mBio ; 11(5)2020 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-32900810

RESUMEN

Nonlytic exocytosis is a process in which previously ingested microbes are expelled from host phagocytes with the concomitant survival of both cell types. This process has been observed in the interaction of Cryptococcus spp. and other fungal cells with phagocytes as distant as mammalian, bird, and fish macrophages and ameboid predators. Despite a great amount of research dedicated to unraveling this process, there are still many questions about its regulation and its final benefits for host or fungal cells. During a study to characterize the virulence attributes of Brazilian clinical isolates of C. neoformans, we observed great variability in their rates of nonlytic exocytosis and noted a correlation between this process and fungal melanin production/laccase activity. Flow cytometry experiments using melanized cells, nonmelanized cells, and lac1Δ mutants revealed that laccase has a role in the process of nonlytic exocytosis that seems to be independent of melanin production. These results identify a role for laccase in virulence, independent of its role in pigment production, that represents a new variable in the regulation of nonlytic exocytosis.IMPORTANCECryptococcus neoformans is a yeast that causes severe disease, primarily in immunosuppressed people. It has many attributes that allow it to survive and cause disease, such as a polysaccharide capsule and the dark pigment melanin produced by the laccase enzyme. Upon infection, the yeast is ingested by cells called macrophages, whose function is to kill them. Instead, these fungal cells can exit from macrophages in a process called nonlytic exocytosis. We know that this process is controlled by both host and fungal factors, only some of which are known. As part of an ongoing study, we observed that C. neoformans isolates that produce melanin faster are more-frequent targets of nonlytic exocytosis. Further experiments showed that this is probably due to higher production of laccase, because fungi lacking this enzyme are nonlytically exocytosed less often. This shows that laccase is an important signal/regulator of nonlytic exocytosis of C. neoformans from macrophages.


Asunto(s)
Cryptococcus neoformans/enzimología , Cryptococcus neoformans/patogenicidad , Exocitosis , Lacasa/metabolismo , Macrófagos/microbiología , Animales , Brasil , Células Cultivadas , Criptococosis/inmunología , Criptococosis/microbiología , Cryptococcus neoformans/genética , Humanos , Huésped Inmunocomprometido , Lacasa/análisis , Lacasa/biosíntesis , Lacasa/genética , Melaninas/metabolismo , Ratones , Ratones Endogámicos BALB C , Virulencia
14.
Fungal Genet Biol ; 140: 103395, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32325168

RESUMEN

Paracoccidioidomycosis (PCM) is a life-threatening systemic mycosis widely reported in the Gran Chaco ecosystem. The disease is caused by different species from the genus Paracoccidioides, which are all endemic to South and Central America. Here, we sequenced and analyzed 31 isolates of Paracoccidioides across South America, with particular focus on isolates from Argentina and Paraguay. The de novo sequenced isolates were compared with publicly available genomes. Phylogenetics and population genomics revealed that PCM in Argentina and Paraguay is caused by three distinct Paracoccidioides genotypes, P. brasiliensis (S1a and S1b) and P. restrepiensis (PS3). P. brasiliensis S1a isolates from Argentina are frequently associated with chronic forms of the disease. Our results suggest the existence of extensive molecular polymorphism among Paracoccidioides species, and provide a framework to begin to dissect the connection between genotypic differences in the pathogen and the clinical outcomes of the disease.


Asunto(s)
Variación Genética/genética , Genómica , Paracoccidioides/genética , Paracoccidioidomicosis/genética , Argentina/epidemiología , Ecosistema , Genética de Población , Genoma Fúngico/genética , Genotipo , Humanos , Paracoccidioides/clasificación , Paracoccidioides/patogenicidad , Paracoccidioidomicosis/clasificación , Paracoccidioidomicosis/epidemiología , Paracoccidioidomicosis/microbiología , Paraguay/epidemiología , Filogenia
15.
Fungal Genet Biol ; 138: 103367, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32198121

RESUMEN

Filamentous fungi are well known for producing secondary metabolites applied in various industrial segments. Among these, lovastatin and itaconic acid, produced by Aspergillus terreus, have applications in the pharmaceutical and chemical industries. Lovastatin is primarily used for the control of hypercholesterolemia, while itaconic acid is a building block for the production of synthetic fibers, coating adhesives, among others. In this study, for the first time, 35 strains of Aspergillus sp. from four Brazilian culture collections were evaluated for lovastatin and itaconic acid production and compared to a reference strain, ATCC 20542. From an initial screening, the strains ATCC 20542, URM 224, URM1876, URM 5061, URM 5254, URM 5256, URM 5650, and URM 5961 were selected for genomic comparison. Among tested strains, the locus corresponding to the lovastatin genomic cluster was assembled, showing that all genes essential for lovastatin biosynthesis were present in producing URM 5961 and URM 5650 strains, with 100% and 98.5% similarity to ATCC 20542, respectively. However, in the no producing URM 1876, URM 224, URM 5254, URM 5061, and URM 5256 strains, this cluster was either fragmented or missing. Among the 35 strains evaluated for itaconic acid production in this study, only three strains had titers above 0.5 g/L, 16 strains had production below 0.5 g/L, and the remaining 18 strains had no production, with the highest production of itaconic acid observed in the URM 5254 strain with 2.2 g/L. The essential genes for itaconic acid production, mttA, cadA msfA were also mapped, where all three genes linked to itaconic acid production were found in a single contig in the assembly of each strain. In contrast to lovastatin loci, there is no correlation between the level of itaconic acid production and genetic polymorphisms in the genes associated with its biosynthesis.


Asunto(s)
Aspergillus , Lovastatina , Succinatos , Aspergillus/genética , Aspergillus/metabolismo , Biodiversidad , Brasil , Genes Fúngicos , Variación Genética , Genoma Fúngico , Lovastatina/biosíntesis , Lovastatina/genética , Filogenia , Succinatos/metabolismo
16.
Biochem Biophys Rep ; 21: 100724, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32021910

RESUMEN

An elevated prevalence of cryptococcal infection is a tendency in low-income countries and constitutes a global public health problem due to factors such as the limited efficacy of antifungal therapy and the AIDS/transplant immunocompromised patients. The fungus Cryptococcus neoformans, implicated in this burden, has had several genes validated as drug targets. Among them, the thioredoxin system is one of the major regulators of redox homeostasis and antioxidant defense acting on protein disulfide bonds. Thioredoxin 1 from C. neoformans (CnTrx1) was cloned and expressed in E. coli and the recombinant protein was purified and crystallized. Functional assay shows that CnTrx1 catalyzes the reduction of insulin disulfide bonds using dithiothreitol, while acting as a monomer in solution. The crystal structure of oxidized CnTrx1 at 1.80 Å resolution presents a dimer in the asymmetric unit with typical Trx-fold. Differences between the monomers in the asymmetric unit are found specially in the loop leading to the Cys-Gly-Pro-Cys active-site motif, being even larger when compared to those found between reduced and oxidized states of other thioredoxins. Although the thioredoxins have been isolated and characterized from many organisms, this new structural report provides important clues for understanding the binding and specificity of CnTrx1 to its targets.

17.
J Fungi, v. 6, n. 4, 193, set. 2020
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3257

RESUMEN

Paracoccidioidomycosis (PCM) is one of the most frequent systemic mycoses in Latin America. It affects mainly male rural workers in impoverished regions, and the therapy can last up to two years or use drugs that are very toxic. Given the need for novel safe and effective approaches to treat PCM, we have been developing monoclonal antibodies (mAbs) that could be used not only to block specific fungal targets, but also modulate the host’s antifungal immunity. In this work we show the generation of and promising results with an mAb against Heat Shock Protein (HSP)90, a molecular chaperone that is an important virulence factor in fungi. Using recombinant Paracoccidioides lutzii (Pb01) and P. brasiliensis (Pb18) HSP90 proteins produced in E. coli, we immunized mice and generated polyclonal antibodies and an IgG1 hybridoma mAb. The proteins were very immunogenic and both the polyclonal serum and mAb were used in immunofluorescence experiments, which showed binding of antibodies to the yeast cell surface. The mAb successfully opsonized P. lutzii and P. brasiliensis cells in co-incubations with J774.16 macrophage-like cells. Our results suggest that this mAb could serve as the basis for new immunotherapy regimens for PCM

18.
Saúde debate ; 43(spe2): 75-86, nov. 2019. graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1059035

RESUMEN

RESUMO O estudo objetivou prospectar grupos e temas de pesquisa translacional no Brasil, que detenham potencial de transformar pesquisa em soluções para saúde no âmbito nacional, e avaliar se existe convergência com a Agenda de Prioridades de Pesquisa do Ministério da Saúde, a Agenda. Estudo exploratório, descritivo, realizado a partir de busca em bases de dados públicos de acesso livre. Foram localizados 64 programas/grupos, sendo 8 programas de pós-graduação, 12 programas de pesquisa e 44 grupos na área de pesquisa translacional em saúde cadastrados no Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). A maioria dos programas de pós-graduação e todos os programas de pesquisa são vinculados a Instituições Públicas da região Sudeste. A análise temática não incluiu os 20 programas de pesquisa/pós-graduação existentes. Os 44 grupos de pesquisa foram categorizados de acordo com os 14 eixos temáticos e com as 172 linhas de pesquisa da Agenda por 4 pesquisadores independentes e cegados. Os resultados mostraram a inexistência de aderência entre os temas de pesquisa desses grupos e a Agenda de prioridades do Sistema Único de Saúde (SUS). Em cenário de aumento de demanda de necessidades em saúde, a pesquisa translacional permitiria reduzir o distanciamento da pesquisa desenvolvida no Brasil com as necessidades do SUS.


ABSTRACT This study aims to prospect groups and themes of translational research in Brazil that have the potential of transforming research into solutions for health nationally. It also aims to evaluate whether or not there is convergence with the 2018 Agenda of Research Priorities of the Ministry of Health, the Agenda. This is an exploratory, descriptive study, based on a search in public databases of free access. Sixty-four programs/groups were located: eight postgraduate programs, 12 research programs, and 44 groups linked to translational health research. Most of the postgraduate programs and all research programs are linked to Public Institutions in the Southeast region. The thematic analysis did not include the 20 ongoing research/graduate programs. The 44 research groups were categorized according to the 14 thematic axes and the 172 lines of research of the Agenda lead by four independent and blinded researchers. The results showed the inexistence of adherence between the themes these groups investigate and the SUS (Unified Health System) priority Agenda. In a scenario of increasing demand for health needs, translational research could reduce distancing between the research developed in Brazil and the necessities of the SUS.

20.
Biotechnol Lett ; 41(12): 1391-1401, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31659577

RESUMEN

OBJECTIVE: To select potential ligands of ALS3 for drug development with anti-adhesion and/or anti-biofilm activities. METHODOLOGY: ALS3 model was considered stable by DM. The main features of protein flexibility were represented by two conformers which were used in the virtual screening. Twenty-four small molecules were selected for in vitro assays. Five of them presented the best biological activity with ability to inhibit the adhesion and C. albicans biofilm formation on abiotic surface. RESULTS: To select potential ligands of ALS3 for drug development with anti-adhesion and/or anti-biofilm activities. CONCLUSION: In silico tools application was able to select promising compounds with anti-adhesion activity, opening a new perspective of medical device treatment.


Asunto(s)
Antifúngicos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Adhesión Celular/efectos de los fármacos , Descubrimiento de Drogas/métodos , Proteínas Fúngicas/antagonistas & inhibidores , Simulación del Acoplamiento Molecular/métodos , Antifúngicos/química , Biopelículas/efectos de los fármacos , Proteínas Fúngicas/química , Unión Proteica , Conformación Proteica
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