5 results on '"de Souza, Marcos Romário Matos"'
Search Results
2. Evaluation of SARS-CoV-2 ORF7a Deletions from COVID-19-Positive Individuals and Its Impact on Virus Spread in Cell Culture.
- Author
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Simas, Maria Clara da Costa, Costa, Sara Mesquita, Gomes, Priscila da Silva Figueiredo Celestino, Cruz, Nádia Vaez Gonçalves da, Corrêa, Isadora Alonso, de Souza, Marcos Romário Matos, Dornelas-Ribeiro, Marcos, Nogueira, Tatiana Lucia Santos, Santos, Caleb Guedes Miranda dos, Hoffmann, Luísa, Tanuri, Amilcar, Moura-Neto, Rodrigo Soares de, Damaso, Clarissa R., Costa, Luciana Jesus da, and Silva, Rosane
- Subjects
SARS-CoV-2 ,CELL culture ,VIRAL transmission - Abstract
The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing the COVID-19 outbreak, posed a primary concern of public health worldwide. The most common changes in SARS-CoV-2 are single nucleotide substitutions, also reported insertions and deletions. This work investigates the presence of SARS-CoV-2 ORF7a deletions identified in COVID-19-positive individuals. Sequencing of SARS-CoV-2 complete genomes showed three different ORF7a size deletions (190-nt, 339-nt and 365-nt). Deletions were confirmed through Sanger sequencing. The ORF7a∆190 was detected in a group of five relatives with mild symptoms of COVID-19, and the ORF7a∆339 and ORF7a∆365 in a couple of co-workers. These deletions did not affect subgenomic RNAs (sgRNA) production downstream of ORF7a. Still, fragments associated with sgRNA of genes upstream of ORF7a showed a decrease in size when corresponding to samples with deletions. In silico analysis suggests that the deletions impair protein proper function; however, isolated viruses with partial deletion of ORF7a can replicate in culture cells similarly to wild-type viruses at 24 hpi, but with less infectious particles after 48 hpi. These findings on deleted ORF7a accessory protein gene, contribute to understanding SARS-CoV-2 phenotypes such as replication, immune evasion and evolutionary fitness as well insights into the role of SARS-CoV-2_ORF7a in the mechanism of virus-host interactions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. The interplay between ventro striatal BDNF levels and the effects of valproic acid on the acquisition of ethanol-induced conditioned place preference in mice.
- Author
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Júniordos Santos, Manuel Alves, Escudeiro, Sarah Sousa, Vasconcelos, Germana Silva, Matos, Natália Castelo Branco, de Souza, Marcos Romário Matos, Patrocínio, Manoel Cláudio Azevedo, Dantas, Leonardo Pimentel, Macêdo, Danielle, and Vasconcelos, Silvânia Maria Mendes
- Subjects
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BRAIN-derived neurotrophic factor , *VALPROIC acid , *ALCOHOLISM , *BRAIN diseases , *CHRONIC diseases - Abstract
Alcohol addiction is a chronic, relapsing and progressive brain disease with serious consequences for health. Compulsive use of alcohol is associated with the capacity to change brain structures involved with the reward pathway, such as ventral striatum. Recent evidence suggests a role of chromatin remodeling in the pathophysiology of alcohol dependence and addictive-like behaviors. In addition, neuroadaptive changes mediated by the brain-derived neurotrophic factor (BDNF) seems to be an interesting pharmacological target for alcoholism treatment. In the present study, we evaluated the effects of the deacetylase inhibitor valproic acid (VPA) (300 mg/kg) on the conditioned rewarding effects of ethanol using conditioned place preference (CPP) (15% v/v; 2 g/kg). Ethanol rewarding effect was investigated using a biased protocol of CPP. BDNF levels were measured in the ventral striatum. Ethanol administration induced CPP. VPA pretreatment did not reduce ethanol-CPP acquisition. VPA pretreatment increased BDNF levels when compared to ethanol induced-CPP. VPA pretreatment increased BDNF levels even in saline conditioned mice. Taken together, our results indicate a modulatory effect of VPA on the BDNF levels in the ventral striatum. Overall, this study brings initial insights into the involvement of neurotrophic mechanisms in the ventral striatum in ethanol-induced addictive-like behavior. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
4. Prolonged SARS-CoV-2 Positivity in Immunocompetent Patients: Virus Isolation, Genomic Integrity, and Transmission Risk.
- Author
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Leitão IC, Calil PT, Galliez RM, Moreira FRR, Mariani D, Castiñeiras ACP, da Silva GPD, Maia RA, Corrêa IA, Monteiro FLL, de Souza MRM, Gonçalves CCA, Higa LM, de Jesus Ribeiro L, Fonseca VWP, Bastos VC, Voloch CM, Faffe DS, da Costa Ferreira O Jr, Tanuri A, Castiñeiras TMPP, and da Costa LJ
- Subjects
- Adult, COVID-19 diagnosis, Female, Genome, Viral, Genomics, Humans, Male, Middle Aged, Nasopharynx virology, Patient Isolation, Viral Load, Viral Proteins isolation & purification, Virus Shedding, COVID-19 immunology, COVID-19 virology, COVID-19 Nucleic Acid Testing methods, SARS-CoV-2 genetics, SARS-CoV-2 isolation & purification
- Abstract
Current guidelines for patient isolation in COVID-19 cases recommend a symptom-based approach, averting the use of control real-time reverse transcription PCR (rRT-PCR) testing. However, we hypothesized that patients with persistently positive results by RT-PCR for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be potentially infectious for a prolonged time, even if immunocompetent and asymptomatic, which would demand a longer social isolation period than presently recommended. To test this hypothesis, 72 samples from 51 mildly symptomatic immunocompetent patients with long-lasting positive rRT-PCR results for SARS-CoV-2 were tested for their infectiousness in cell culture. The serological response of samples from those patients and virus genomic integrity were also analyzed. Infectious viruses were successfully isolated from 34.38% (22/64) of nasopharynx samples obtained 14 days or longer after symptom onset. Indeed, we observed successful virus isolation up to 128 days. Complete SARS-COV-2 genome integrity was demonstrated, suggesting the presence of replication-competent viruses. No correlation was found between the isolation of infectious viruses and rRT-PCR cycle threshold values or the humoral immune response. These findings call attention to the need to review current isolation guidelines, particularly in scenarios involving high-risk individuals. IMPORTANCE In this study, we evaluated mildly symptomatic immunocompetent patients with long-lasting positive rRT-PCR results for SARS-CoV-2. Infectious viruses were successfully isolated in cell cultures from nasopharynx samples obtained 14 days or longer after symptom onset. Indeed, we observed successful virus isolation for up to 128 days. Moreover, SARS-CoV-2 genome integrity was demonstrated by sequencing, suggesting the presence of replication-competent viruses. These data point out the risk of continuous SARS-CoV-2 transmission from patients with prolonged detection of SARS-CoV-2 in the upper respiratory tract, which has important implications for current precaution guidelines, particularly in settings where vulnerable individuals may be exposed (e.g., nursing homes and hospitals).
- Published
- 2021
- Full Text
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5. The interplay between ventro striatal BDNF levels and the effects of valproic acid on the acquisition of ethanol-induced conditioned place preference in mice.
- Author
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Dos Santos MA Júnior, Escudeiro SS, Vasconcelos GS, Matos NCB, de Souza MRM, Patrocínio MCA, Dantas LP, Macêdo D, and Vasconcelos SMM
- Subjects
- Animals, Conditioning, Classical drug effects, Male, Mice, Reward, Brain-Derived Neurotrophic Factor metabolism, Drug-Seeking Behavior, Ethanol administration & dosage, Valproic Acid administration & dosage, Ventral Striatum drug effects, Ventral Striatum metabolism
- Abstract
Alcohol addiction is a chronic, relapsing and progressive brain disease with serious consequences for health. Compulsive use of alcohol is associated with the capacity to change brain structures involved with the reward pathway, such as ventral striatum. Recent evidence suggests a role of chromatin remodeling in the pathophysiology of alcohol dependence and addictive-like behaviors. In addition, neuroadaptive changes mediated by the brain-derived neurotrophic factor (BDNF) seems to be an interesting pharmacological target for alcoholism treatment. In the present study, we evaluated the effects of the deacetylase inhibitor valproic acid (VPA) (300mg/kg) on the conditioned rewarding effects of ethanol using conditioned place preference (CPP) (15% v/v; 2g/kg). Ethanol rewarding effect was investigated using a biased protocol of CPP. BDNF levels were measured in the ventral striatum. Ethanol administration induced CPP. VPA pretreatment did not reduce ethanol-CPP acquisition. VPA pretreatment increased BDNF levels when compared to ethanol induced-CPP. VPA pretreatment increased BDNF levels even in saline conditioned mice. Taken together, our results indicate a modulatory effect of VPA on the BDNF levels in the ventral striatum. Overall, this study brings initial insights into the involvement of neurotrophic mechanisms in the ventral striatum in ethanol-induced addictive-like behavior., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
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