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1.
Viruses ; 16(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38932149

RESUMO

DNA viruses that produce persistent infections have been proposed as potential causes for the extinction of Neanderthals, and, therefore, the identification of viral genome remnants in Neanderthal sequence reads is an initial step to address this hypothesis. Here, as proof of concept, we searched for viral remnants in sequence reads of Neanderthal genome data by mapping to adenovirus, herpesvirus and papillomavirus, which are double-stranded DNA viruses that may establish lifelong latency and can produce persistent infections. The reconstructed ancient viral genomes of adenovirus, herpesvirus and papillomavirus revealed conserved segments, with nucleotide identity to extant viral genomes and variable regions in coding regions with substantial divergence to extant close relatives. Sequence reads mapped to extant viral genomes showed deamination patterns of ancient DNA, and these ancient viral genomes showed divergence consistent with the age of these samples (≈50,000 years) and viral evolutionary rates (10-5 to 10-8 substitutions/site/year). Analysis of random effects showed that the Neanderthal mapping to genomes of extant persistent viruses is above what is expected by random similarities of short reads. Also, negative control with a nonpersistent DNA virus does not yield statistically significant assemblies. This work demonstrates the feasibility of identifying viral genome remnants in archaeological samples with signal-to-noise assessment.


Assuntos
DNA Antigo , Genoma Viral , Homem de Neandertal , Animais , Homem de Neandertal/genética , Homem de Neandertal/virologia , DNA Antigo/análise , Evolução Molecular , DNA Viral/genética , Análise de Sequência de DNA/métodos , Humanos , Filogenia , Vírus de DNA/genética , Vírus de DNA/classificação , Vírus de DNA/isolamento & purificação , Fósseis/virologia
2.
Front Cell Infect Microbiol ; 12: 906578, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051243

RESUMO

The epitranscriptomics of the SARS-CoV-2 infected cell reveals its response to viral replication. Among various types of RNA nucleotide modifications, the m6A is the most common and is involved in several crucial processes of RNA intracellular location, maturation, half-life and translatability. This epitranscriptome contains a mixture of viral RNAs and cellular transcripts. In a previous study we presented the analysis of the SARS-CoV-2 RNA m6A methylation based on direct RNA sequencing and characterized DRACH motif mutations in different viral lineages. Here we present the analysis of the m6A transcript methylation of Vero cells (derived from African Green Monkeys) and Calu-3 cells (human) upon infection by SARS-CoV-2 using direct RNA sequencing data. Analysis of these data by nonparametric statistics and two computational methods (m6anet and EpiNano) show that m6A levels are higher in RNAs of infected cells. Functional enrichment analysis reveals increased m6A methylation of transcripts involved in translation, peptide and amine metabolism. This analysis allowed the identification of differentially methylated transcripts and m6A unique sites in the infected cell transcripts. Results here presented indicate that the cell response to viral infection not only changes the levels of mRNAs, as previously shown, but also its epitranscriptional pattern. Also, transcriptome-wide analysis shows strong nucleotide biases in DRACH motifs of cellular transcripts, both in Vero and Calu-3 cells, which use the signature GGACU whereas in viral RNAs the signature is GAACU. We hypothesize that the differences of DRACH motif biases, might force the convergent evolution of the viral genome resulting in better adaptation to target sequence preferences of writer, reader and eraser enzymes. To our knowledge, this is the first report on m6A epitranscriptome of the SARS-CoV-2 infected Vero cells by direct RNA sequencing, which is the sensu stricto RNA-seq.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Viés , Chlorocebus aethiops , Humanos , Nucleotídeos , RNA Viral/genética , SARS-CoV-2/genética , Análise de Sequência de RNA , Células Vero
3.
Crit Rev Oncol Hematol ; 131: 30-34, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30293703

RESUMO

Squamous-cell carcinoma of the head and neck (SCCHN) is an important problem in Brazil, where epidemiological and socioeconomic features often create barriers to the implementation of combined modalities with curative potential. Cisplatin improves the efficacy of radiotherapy in the adjuvant treatment of localized SCCHN and in the definitive therapy of locally advanced disease. However, the addition of high-dose cisplatin to radiotherapy increases treatment toxicity and is not always warranted. A panel of experts convened in Sao Paulo, Brazil, for discussions and recommendations regarding the use of high-dose cisplatin in combination with radiotherapy in SCCHN. In addition to discussing their professional experience, panel members used the current literature to provide evidence-based, practical recommendations regarding sociodemographic or medical criteria that may preclude safe administration of cisplatin. It is hoped that the application of these recommendations in clinical practice may improve therapeutic results in Brazil and other countries with similar health-care environments.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Cisplatino/uso terapêutico , Prova Pericial , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Seleção de Pacientes , Consenso , Humanos
4.
J Med Case Rep ; 8: 326, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25280468

RESUMO

INTRODUCTION: Primary hypoparathyroidism is a rare condition caused by parathyroid hormone deficiency and characterized by hypocalcemia. The clinical manifestations of primary hypoparathyroidism include tetany, seizures, paresthesias, dementia, and parkinsonism. Psychiatric manifestations such as mood disorders are unusual and may constitute a major diagnostic challenge, especially if the typical manifestations caused by hypocalcemia are absent. CASE PRESENTATION: The patient was a 22-year-old Caucasian man with a history of chronic omeprazole use and periodic seizures, who presented to the emergency department of a secondary hospital in Southern Brazil with symptoms of major depression (sadness, anhedonia, loss of appetite, insomnia, and fatigue) associated with paresthesias affecting his toes. The initial electrocardiogram revealed a prolonged QTc interval. A computed tomography scan of his brain revealed bilateral, nonenhancing hyperdense calcifications involving the putamen and caudate nucleus. An electroencephalogram showed generalized bursts of slow spikes. Blood laboratory study results indicated serum hypocalcemia, hypomagnesemia, and hyperphosphatemia associated with a low parathyroid hormone level. His serum levels of albumin, 25-hydroxyvitamin D, thyroid-stimulating hormone, T3 and T4 thyroid hormones, as well as the results of kidney function tests, were normal. The definitive diagnosis was primary hypoparathyroidism with psychiatric manifestations due to chronic hypomagnesemia induced by proton pump inhibitor use. CONCLUSIONS: In some cases, to differentiate between a primary psychiatric disorder and primary hypoparathyroidism with neuropsychiatric symptoms may represent a challenge given that the classical manifestations of hypocalcemia, especially tetany, may be absent in the setting of chronic hypoparathyroidism. Clinicians and psychiatrists should consider primary hypoparathyroidism part of the differential diagnosis during the evaluation of patients with mood symptoms, especially in the context of atypical presentations associated with hypocalcemia.


Assuntos
Transtorno Depressivo Maior/etiologia , Hipoparatireoidismo/diagnóstico , Doença Crônica , Transtorno Depressivo Maior/diagnóstico , Humanos , Hipoparatireoidismo/complicações , Masculino , Adulto Jovem
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