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Epitranscriptome machinery in Trypanosomatids: New players on the table?
No full textTrypanosoma and Leishmania parasites cause devastating tropical diseases resulting in serious global health consequences. These organisms have complex life cycles with mammalian hosts and insect vectors. The parasites must, therefore, survive in different environments, demanding rapid physiological and metabolic changes. These responses depend upon regulation of gene expression, which primarily occurs posttranscriptionally. Altering the composition or conformation of RNA through nucleotide modifications is one posttranscriptional mechanism of regulating RNA fate and function, and modifications including N6-methyladenosine (m6A), N1-methyladenosine (m1A), N5-methylcytidine (m5C), N4-acetylcytidine (ac4C), and pseudouridine (Ψ), dynamically regulate RNA stability and translation in diverse organisms. Little is known about RNA modifications and their machinery in Trypanosomatids, but we hypothesize that they regulate parasite gene expression and are vital for survival. Here, we identified Trypanosomatid homologs for writers of m1A, m5C, ac4C, and Ψ and analyze their evolutionary relationships. We systematically review the evidence for their functions and assess their potential use as therapeutic targets. This work provides new insights into the roles of these proteins in Trypanosomatid parasite biology and treatment of the diseases they cause and illustrates that Trypanosomatids provide an excellent model system to study RNA modifications, their molecular, cellular, and biological consequences, and their regulation and interplay
Caracterización molecular y evaluación de la formación y tolerancia al Biopelicula de Pseudomonas aeruginosa aislado de aguas minerales naturales
No full textPseudomonas aeruginosa é um patógeno oportunista associado a doenças transmitidas por águas e,
possui a capacidade de formar biofilme em superfícies. Neste estudo, seis cepas de P. aeruginosa
isoladas de águas minerais naturais em embalagens reutilizáveis de 20L foram submetidas à
caracterização molecular por ERIC-PCR e avaliadas quanto à formação de biofilme. O ERIC-PCR
revelou que as seis cepas apresentaram perfis genotípicos distintos. Nenhuma cepa apresentou formação
de biofilme na matriz aço inox. Na matriz poliestireno houve formação de biofilme e a exposição ao
hipoclorito de sódio a nas concentrações de 1% e 2% eliminou o biofilme formado. Contudo, na
concentração 0,02% o biofilme formado não foi eliminado mesmo após 60 min de contato. O consumo
de águas minerais contaminadas por P. aeruginosa e a possibilidade de formação de biofilmes em
bebedouros de plástico podem representar um risco para indivíduos pertencentes ao grupo de risco,
como grávidas, imunossuprimidos e idosos.Pseudomonas aeruginosa is an opportunistic pathogen associated with waterborne diseases and has the
ability to form biofilms on surfaces. In this study, six samples of P. aeruginosa isolated from mineral
waters in 20 L mineral water returnerd plastic bottled were subjected to molecular characterization by
ERIC-PCR and evaluating biofilm formation. ERIC-PCR revealed that six strains detected distinct
genetic genes. No strain shows biofilm formation in the stainless steel matrix. In the polystyrene matrix,
biofilm was formed and exposure to sodium hypochlorite in the ranges of 1% and 2% eliminated the
biofilm formed. However, at a concentration of 0.02% in the biofilm formed, it was not eliminated after
60 minutes of contact. The consumption of mineral waters contaminated by P. aeruginosa and the
possibility of biofilm formation in plastic waterer can represent a risk for individuals belonging to the
risk group, such as pregnant women, immunosuppressed and elderly people.Pseudomonas aeruginosa es un patógeno oportunista asociado con enfermedades transmitidas por el
agua y tiene la capacidad de formar biopelículas en las superficies. En este estudio, seis cepas de P.
aeruginosa aisladas de aguas minerales naturales en envases reutilizables de 20 litros se presentada a
caracterización molecular mediante ERIC-PCR y se evaluó la formación de biopelículas. ERIC-PCR
reveló que las seis cepas tenían perfiles genotípicos distintos. Ninguna deformación presentó formación
de biopelícula en la matriz de acero inoxidable. En la matriz de poliestireno se formó la biopelícula y la
exposición a hipoclorito de sodio en concentraciones de 1% y 2% eliminó la biopelícula formada. Sin
embargo, a una concentración de 0,02%, la biopelícula formada no se eliminó incluso después de 60
minutos de contacto. El consumo de aguas minerales contaminadas por P. aeruginosa y la posibilidad
de formación de biopelículas en bebederos de plástico pueden representar un riesgo para las personas
pertenecientes al grupo de riesgo, como mujeres embarazadas, personas inmunodeprimidas y ancianos
Metal and Metalloid Contamination in Green Sea Turtles (Chelonia mydas) Found Stranded in Southeastern Brazil
No full textSea turtles tend to accumulate high metal levels in their tissues and are considered
excellent pollution bioindicators. Studies concerning metal contamination in hatchlings,
however, are non-existent for one of the most abundant species in Brazil, green sea
turtles, while several other metal assessments in juvenile muscles are still scarce.
In this context, this study aimed to analyze the concentrations of 12 elements
in kidney and muscle samples from green sea turtles (Chelonia mydas; n = 24)
found stranded in Rio de Janeiro, southeastern Brazil. Elemental concentrations were
determined by inductively coupled plasma mass spectrometry (ICP-MS). The presence
of fibropapillomatosis, an increasingly common disease in sea turtles which has been
associated to metal contamination, was also evaluated. Most elements (Mn, Fe,
Co, Ni, Cu, Zn, Cd, Hg, and Pb) were significantly higher in liver, while Al and As
were significantly higher in muscle tissue, indicating bioaccumulation of the latter
two elements. No differences between juvenile male and female green turtles were
observed for either liver or kidney concerning the investigated elements. Literature
comparisons of studies conducted in other areas throughout the Brazilian coast
indicate higher concentrations of Cd, Mn, As, Hg, and Zn in kidneys, of probable
anthropogenic origin. Several statistically significant inter-elemental correlations were
observed between toxic elements, indicating similar sources for these environmental
contaminants. Significant correlations between Hg in muscle and kidney and As in the
same organs suggest bioaccumulation of both elements in muscle. Three individuals assessed herein exhibited fibropapillomatosis, and further assessments in this regard
and potential correlations to the detected metal concentrations are currently being
carried out. In addition, evaluations concerning other toxic compounds, as well as
deleterious cellular effects, are also underway, since total metal concentrations do not
reflect total elemental bioavailability
Vaginal Viral Shedding With Undetectable Plasma HIV Viral Load in Pregnant Women Receiving 2 Different Antiretroviral Regimens: A Randomized Clinical Trial
No full textBackground: Pregnant women using antiretrovirals (ARVs) may have persistent vaginal viral shedding, which could be associated with sexual and perinatal HIV transmission. However, there are scant data on vaginal viral load (VVL) in pregnant women with undetectable plasma viral load (PVL).
Methods: This study was a post hoc analysis of an open-label randomized trial to evaluate the virologic response of 2 ART regimens. The participants were ART-naive women living with HIV initiating ART regimens between 20 and 36 weeks of pregnancy recruited at 19 clinical sites in 6 countries. Participants were randomized to receive 400 mg of raltegravir 2 times a day or 600 mg of efavirenz 4 times a day in addition to 150 mg of lamivudine and 300 mg of zidovudine 2 times a day. VVL and PVL tests were performed at every study visit. The primary outcome measures were HIV-1 PVL and VVL at maternal study week 4 and rates of perinatal HIV transmission.
Results: A total of 408 were enrolled, of whom 323 had VVL samples 4 weeks after enrollment and were included in this analysis. Among women with undetectable/nonquantifiable PVL during ART, the overall rate of quantifiable VVL at week 4 was 2.54% (7/275). Of the 275 with nonquantifiable PVL, 99.1% (115/116) and 96.2% (153/159) had nonquantifiable VVL in the efavirenz and raltegravir arms, respectively. None of the 7 women with quantifiable VVL at the week 4 study visit transmitted HIV to their infants.
Conclusions: Detectable VVL in pregnant women with undetectable/nonquantifiable PVL while receiving ART was rare and not associated with perinatal HIV transmissio
Characterising four Sarconesiopsis magellanica (Diptera: Calliphoridae) larval fat body-derived antimicrobial peptides
No full textBACKGROUND The inappropriate use of antibiotics has led to the accelerated growth of resistance to antibiotics. The search for
new therapeutic strategies (i.e., antimicrobial peptides-AMPs) has thus become a pressing need.
OBJECTIVE Characterising and evaluating Sarconesiopsis magellanica larval fat body-derived AMPs.
METHODS Fat body extracts were analysed by reversed-phase high-performance liquid chromatography (RP-HPLC); mass
spectrometry was used for characterising the primary structure of the AMPs so found. ProtParam (Expasy) was used for
analysing the AMPs’ physico-chemical properties. Synthetic AMPs’ antibacterial activity was evaluated.
FINDINGS Four new AMPs were obtained and called sarconesin III, IV, V and VI. Sarconesin III had an α-helix structure and
sarconesins IV, V and VI had linear formations. Oligomer prediction highlighted peptide-peptide interactions, suggesting that
sarconesins III, V and VI could form self-aggregations when in contact with the microbial membrane. AMPs synthesised from
their native molecules’ sequences had potent activity against Gram-positive bacteria and, to a lesser extent, against Gram-negative
and drug-resistant bacteria. Sarconesin VI was the most efficient AMP. None of the four synthetic AMPs had a cytotoxic effect.
MAIN CONCLUSIONS S. magellanica larval fat body-derived antimicrobial peptides are an important source of AMPs and could
be used in different antimicrobial therapies and overcoming bacterial resistance
Characterization of the oatC gene of Neisseria meningitidis serogroup C from 1991 to 2019
No full textOs autores externos submeteram sua publicação para apresentação de trabalho no evento “International Symposium on Immunobiologicals”, que foi coordenado e organizado pelo Instituto de Tecnologia em Imunobiológicos (Bio-Manguinhos), da Fundação Oswaldo Cruz
Boas práticas e controle de qualidade em laboratórios de cultivo celular: parte 2 – contaminações
No full textdubladoVídeo integrante do Curso Princípios básicos do cultivo de células de mamíferos, que aborda o subtema, Boas práticas e controle de qualidade em laboratórios de cultivo celular: Parte 2 – contaminaçõesFiocruzMP4Tópicos em cultura de células de mamíferosPrograma de Pós-Graduação em Biociências e Biotecnologi
Prevalence of hepatitis A in the capitals of the States of North, Southeast and South regions of Brazil: decrease in prevalence and some consequences
No full textAnalysis of the c-Myc tag presence in the CAR’s antigen-recognition domain structural stability, through molecular dynamics simulation
No full textOs autores externos submeteram sua publicação para apresentação de trabalho no evento “International Symposium on Immunobiologicals”, que foi coordenado e organizado pelo Instituto de Tecnologia em Imunobiológicos (Bio-Manguinhos), da Fundação Oswaldo Cruz
