Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
1.
J Med Virol ; 96(7): e29750, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38953413

RESUMO

The Phylum Cressdnaviricota consists of a large number of circular Rep-encoding single-stranded (CRESS)-DNA viruses. Recently, metagenomic analyzes revealed their ubiquitous distribution in a diverse range of eukaryotes. Data relating to CRESS-DNA viruses in humans remains scarce. Our study investigated the presence and genetic diversity of CRESS-DNA viruses in human vaginal secretions. Vaginal swabs were collected from 28 women between 29 and 43 years old attending a fertility clinic in New York City. An exploratory metagenomic analysis was performed and detection of CRESS-DNA viruses was confirmed through analysis of near full-length sequences of the viral isolates. A phylogenetic tree was based on the REP open reading frame sequences of the CRESS-DNA virus genome. Eleven nearly complete CRESS-DNA viral genomes were identified in 16 (57.1%) women. There were no associations between the presence of these viruses and any demographic or clinical parameters. Phylogenetic analysis indicated that one of the sequences belonged to the genus Gemycircularvirus within the Genomoviridae family, while ten sequences represented previously unclassified species of CRESS-DNA viruses. Novel species of CRESS-DNA viruses are present in the vaginal tract of adult women. Although they be transient commensal agents, the potential clinical implications for their presence at this site cannot be dismissed.


Assuntos
Vírus de DNA , Genoma Viral , Metagenômica , Filogenia , Vagina , Humanos , Feminino , Adulto , Vagina/virologia , Genoma Viral/genética , Vírus de DNA/genética , Vírus de DNA/classificação , Vírus de DNA/isolamento & purificação , DNA Viral/genética , Cidade de Nova Iorque , Análise de Sequência de DNA , Variação Genética
2.
BMC Infect Dis ; 24(1): 612, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902613

RESUMO

BACKGROUND: Predictors of the outcome of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection remain to be fully determined. We evaluated selected viral characteristics and immunological responses that might predict and/or correlate to the clinical outcome of COVID-19. METHODS: For individuals developing divergent clinical outcomes, the magnitude and breadth of T cell-mediated responses were measured within 36 h of symptom onset. Peripheral Blood Mononuclear Cells (PBMCs) were subjected to in vitro stimulation with SARS-CoV-2-based peptides. In addition, SARS-CoV-2 sequences were generated by metagenome, and HLA typing was performed using Luminex technology. FINDINGS: CD4+ T cell activation was negatively correlated with SARS-CoV-2 basal viral load in patients with severe COVID-19 (p = 0·043). The overall cellular immune response, as inferred by the IFN-γ signal, was higher at baseline for patients who progressed to mild disease compared to patients who progressed to severe disease (p = 0·0044). Subjects with milder disease developed higher T cell responses for MHC class I and II-restricted peptides (p = 0·033). INTERPRETATION: Mounting specific cellular immune responses in the first days after symptom onset, as inferred by IFN-γ magnitude in the ELISPOT assay, may efficiently favor a positive outcome. In contrast, progression to severe COVID-19 was accompanied by stronger cellular immune responses, higher CD4 + T cell activation, and a higher number of in silico predicted high-affinity class I HLA alleles.


Assuntos
Linfócitos T CD4-Positivos , COVID-19 , Imunidade Celular , SARS-CoV-2 , Índice de Gravidade de Doença , Humanos , COVID-19/imunologia , SARS-CoV-2/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Linfócitos T CD4-Positivos/imunologia , Adulto , Inflamação/imunologia , Idoso , Carga Viral , Interferon gama/imunologia , Interferon gama/genética , Ativação Linfocitária , Leucócitos Mononucleares/imunologia
3.
J Mol Biol ; 436(11): 168577, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38642883

RESUMO

The Red Queen Hypothesis (RQH), derived from Lewis Carroll's "Through the Looking-Glass", postulates that organisms must continually adapt in response to each other to maintain relative fitness. Within the context of host-pathogen interactions, the RQH implies an evolutionary arms race, wherein viruses evolve to exploit hosts and hosts evolve to resist viral invasion. This study delves into the dynamics of the RQH in the context of virus-cell interactions, specifically focusing on virus receptors and cell receptors. We observed multiple virus-host systems and noted patterns of co-evolution. As viruses evolved receptor-binding proteins to effectively engage with cell receptors, cells countered by altering their receptor genes. This ongoing mutual adaptation cycle has influenced the molecular intricacies of receptor-ligand interactions. Our data supports the RQH as a driving force behind the diversification and specialization of both viral and host cell receptors. Understanding this co-evolutionary dance offers insights into the unpredictability of emerging viral diseases and potential therapeutic interventions. Future research is crucial to dissect the nuanced molecular changes and the broader ecological consequences of this ever-evolving battle. Here, we combine phylogenetic inferences, structural modeling, and molecular dynamics analyses to describe the epidemiological characteristics of major Brazilian DENV strains that circulated from 1990 to 2022 from a combined perspective, thus providing us with a more detailed picture on the dynamics of such interactions over time.


Assuntos
Moléculas de Adesão Celular , Vírus da Dengue , Evolução Molecular , Interações Hospedeiro-Patógeno , Receptores de Superfície Celular , Proteínas do Envelope Viral , Envelope Viral , Humanos , Brasil , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/química , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/metabolismo , Interações Hospedeiro-Patógeno/genética , Lectinas Tipo C/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/química , Simulação de Dinâmica Molecular , Filogenia , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/química , Receptores Virais/metabolismo , Receptores Virais/química , Receptores Virais/genética , Envelope Viral/metabolismo , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/química
4.
Microorganisms ; 12(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38674632

RESUMO

CRESS-DNA encompasses a broad spectrum of viruses documented across diverse organisms such as animals, plants, diatoms, fungi, and marine invertebrates. Despite this prevalence, the full extent of these viruses' impact on the environment and their respective hosts remains incompletely understood. Furthermore, an increasing number of viruses within this category lack detailed characterization. This investigation focuses on unveiling and characterizing viruses affiliated with the Genomoviridae family identified in liver samples from the bat Molossus molossus. Leveraging viral metagenomics, we identified seven sequences (MmGmV-PA) featuring a circular DNA genome housing two ORFs encoding replication-associated protein (Rep) and capsid protein (Cap). Predictions based on conserved domains typical of the Genomoviridae family were established. Phylogenetic analysis revealed the segregation of these sequences into two clades aligning with the genera Gemycirculavirus (MmGmV-06-PA and MmGmV-07-PA) and Gemykibivirus (MmGmV-01-PA, MmGmV-02-PA, MmGmV-03-PA, MmGmV-05-PA, and MmGmV-09-PA). At the species level, pairwise comparisons based on complete nucleotide sequences indicated the potential existence of three novel species. In summary, our study significantly contributes to an enhanced understanding of the diversity of Genomoviridae within bat samples, shedding light on previously undiscovered viral entities and their potential ecological implications.

5.
Microorganisms ; 12(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276191

RESUMO

The Totiviridae family of viruses has a unique genome consisting of double-stranded RNA with two open reading frames that encode the capsid protein (Cap) and the RNA-dependent RNA polymerase (RdRpol). Most virions in this family are isometric in shape, approximately 40 nm in diameter, and lack an envelope. There are five genera within this family, including Totivirus, Victorivirus, Giardiavirus, Leishmaniavirus, and Trichomonasvirus. While Totivirus and Victorivirus primarily infect fungi, Giardiavirus, Leishmaniavirus, and Trichomonasvirus infect diverse hosts, including protists, insects, and vertebrates. Recently, new totivirus-like species have been discovered in fish and plant hosts, and through metagenomic analysis, a novel totivirus-like virus (named Tianjin totivirus) has been isolated from bat guano. Interestingly, Tianjin totivirus causes cytopathic effects in insect cells but cannot grow in mammalian cells, suggesting that it infects insects consumed by insectivorous bats. In this study, we used next-generation sequencing and identified totivirus-like viruses in liver tissue from Molossus molossus bats in the Amazon region of Brazil. Comparative phylogenetic analysis based on the RNA-dependent RNA polymerase region revealed that the viruses identified in Molossus bats belong to two distinct phylogenetic clades, possibly comprising different genera within the Totiviridae family. Notably, the mean similarity between the Tianjin totivirus and the totiviruses identified in Molossus bats is less than 18%. These findings suggest that the diversity of totiviruses in bats is more extensive than previously recognized and highlight the potential for bats to serve as reservoirs for novel toti-like viruses.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37878972

RESUMO

Leishmania infantum is a protozoan that causes visceral leishmaniasis (VL) in the Americas and some regions of Europe. The disease is mainly characterized by hepatosplenomegaly and fever, and can be fatal. Factors related to the host and parasite can contribute to the transmission of Leishmania and the clinical outcome. The intraspecific genetic variability of L. infantum strains may be one of these factors. In this study, we evaluated the genetic variability of L. infantum obtained from bone marrow smear slides from patients in the Sao Paulo State, Brazil. For this, the minicircle of the kDNA hypervariable region was used as target by Sanger sequencing. By analyzing the similarity of the nucleotides and the maximum likelihood tree (Fasttree), we observed a high similarity (98%) among samples. Moreover, we identified four different profiles of L. infantum. In conclusion, L. infantum strains from Sao Paulo State, Brazil, showed low diversity measured by minicircle of the kDNA hypervariable region.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Cães , Humanos , Leishmania infantum/genética , Leishmaniose Visceral/parasitologia , DNA de Cinetoplasto/genética , Brasil , Doenças do Cão/parasitologia
7.
BMC Microbiol ; 23(1): 291, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845637

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) is a critical global issue that poses significant threats to human health, animal welfare, and the environment. With the increasing emergence of resistant microorganisms, the effectiveness of current antimicrobial medicines against common infections is diminishing. This study aims to conduct a competitive meta-analysis of surveillance data on resistant microorganisms and their antimicrobial resistance patterns in two countries, Egypt and the United Kingdom (UK). METHODS: Data for this study were obtained from published reports spanning the period from 2013 to 2022. In Egypt and the UK, a total of 9,751 and 10,602 food samples were analyzed, respectively. Among these samples, 3,205 (32.87%) in Egypt and 4,447 (41.94%) in the UK were found to contain AMR bacteria. RESULTS: In Egypt, the predominant resistance was observed against ß-lactam and aminoglycosides, while in the United Kingdom, most isolates exhibited resistance to tetracycline and ß-lactam. The findings from the analysis underscore the increasing prevalence of AMR in certain microorganisms, raising concerns about the development of multidrug resistance. CONCLUSION: This meta-analysis sheds light on the escalating AMR problem associated with certain microorganisms that pose a higher risk of multidrug resistance development. The significance of implementing One Health AMR surveillance is emphasized to bridge knowledge gaps and facilitate accurate AMR risk assessments, ensuring consumer safety. Urgent actions are needed on a global scale to combat AMR and preserve the effectiveness of antimicrobial treatments for the well-being of all living beings.


Assuntos
Anti-Infecciosos , Saúde Única , Animais , Humanos , Antibacterianos/uso terapêutico , beta-Lactamas , Farmacorresistência Bacteriana , Egito , Reino Unido
8.
Front Med (Lausanne) ; 10: 1161091, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547599

RESUMO

Torquetenovirus (TTV) is a commensal virus present in many healthy individuals. Although considered to be non-pathogenic, its presence and titer have been shown to be indicative of altered immune status in individuals with chronic infections or following allogeneic transplantations. We evaluated if TTV was present in amniotic fluid (AF) at the time of in utero surgery to correct a fetal neurological defect, and whether its detection was predictive of adverse post-surgical parameters. AF was collected from 27 women by needle aspiration prior to a uterine incision. TTV titer in the AF was measured by isolation of viral DNA followed by gene amplification and analysis. The TTV genomes were further characterized and sequenced by metagenomics. Pregnancy outcome parameters were subsequently obtained by chart review. Three of the AFs (11.1%) were positive for TTV at 3.36, 4.16, and 4.19 log10 copies/mL. Analysis of their genomes revealed DNA sequences similar to previously identified TTV isolates. Mean gestational age at delivery was >2 weeks earlier (32.5 vs. 34.6 weeks) and the prevalence of respiratory distress was greater (100% vs. 20.8%) in the TTV-positive pregnancies. TTV detection in AF prior to intrauterine surgery may indicate elevated post-surgical risk for earlier delivery and newborn respiratory distress.

9.
PLoS One ; 18(8): e0291027, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37651462

RESUMO

BACKGROUND: Redondovirus (ReDoV) is a DNA virus present in the respiratory tract of many healthy individuals. Since SARS-CoV-2, the virus responsible for COVID-19, also primarily infects the same site, we evaluated whether ReDoV was present at increased frequency in patients with COVID-19 and influenced infection parameters. METHODS: Saliva samples were collected weekly from 59 individuals with COVID-19 and from 132 controls. ReDoV was detected by polymerase chain reaction and the genotypes were identified by metagenomics. Torque Teno Virus (TTV) in these samples were previously reported. RESULTS: ReDoV was detected in saliva more frequently from COVID-19 patients (72.9%) than from controls (50.0%) (p = 0.0015). There were no associations between ReDoV detection and either continuous or intermittent SARS-CoV-2 shedding, the duration of SARS-CoV-2 detection in saliva, patients' sex or if infection was by the B1 or Gamma strain. The two ReDoV strains, Brisavirus and Vientovirus, were present in equivalent frequencies in ReDoV-positive COVID-19 patients and controls. Phylogenetic analysis suggested that the two ReDoV strains in Brazil were similar to strains previously detected on other continents. CONCLUSION: ReDoV expression in saliva is increased in males and females in Brazil with mild COVID-19 but its presence does not appear to influence properties of the SARS-CoV-2 infection.


Assuntos
COVID-19 , SARS-CoV-2 , Feminino , Masculino , Humanos , Brasil/epidemiologia , Filogenia , Saliva
10.
Biomolecules ; 13(8)2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37627247

RESUMO

Antimicrobial resistance (AMR) is a growing public health concern worldwide, and it poses a significant threat to human, animal, and environmental health. The overuse and misuse of antibiotics have contributed significantly and others factors including gene mutation, bacteria living in biofilms, and enzymatic degradation/hydrolyses help in the emergence and spread of AMR, which may lead to significant economic consequences such as reduced productivity and increased health care costs. Nanotechnology offers a promising platform for addressing this challenge. Nanoparticles have unique properties that make them highly effective in combating bacterial infections by inhibiting the growth and survival of multi-drug-resistant bacteria in three areas of health: human, animal, and environmental. To conduct an economic evaluation of surveillance in this context, it is crucial to obtain an understanding of the connections to be addressed by several nations by implementing national action policies based on the One Health strategy. This review provides an overview of the progress made thus far and presents potential future directions to optimize the impact of nanobiotics on AMR.


Assuntos
Antibacterianos , Saúde Única , Animais , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Biofilmes , Análise Custo-Benefício
11.
Virus Genes ; 59(3): 464-472, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37004601

RESUMO

There is a growing interest in phages as potential biotechnological tools in human health owing to the antibacterial activity of these viruses. In this study, we characterized a new member (named PhiV_005_BRA/2016) of the recently identified phage species Phietavirus Henu 2. PhiV_005_BRA/2016 was detected through metagenomic analysis of stool samples of individuals with acute gastroenteritis. PhiV_005_BRA/2016 contains double-stranded linear DNA (dsDNA), it has a genome of 43,513 base pairs (bp), with a high identity score (99%) with phage of the genus Phietavirus, species of Phietavirus Henu 2. Life style prediction indicated that PhiV_005_BRA/2016 is a lysogenic phage whose the main host is methicillin-resistant Staphylococcus aureus (MRSA). Indeed, we found PhiV_005_BRA/2016 partially integrated in the genome of distinct MRSA strains. Our findings highlights the importance of large-scale screening of bacteriophages to better understand the emergence of multi-drug resistant bacterial.


Assuntos
Bacteriófagos , Gastroenterite , Staphylococcus aureus Resistente à Meticilina , Siphoviridae , Infecções Estafilocócicas , Humanos , Viroma , Infecções Estafilocócicas/microbiologia
12.
Viruses ; 15(3)2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36992315

RESUMO

Chaphamaparvovirus (CHPV) is a recently characterized genus of the Parvoviridae family whose members can infect different hosts, including bats, which constitute the second most diverse order of mammals and are described worldwide as important transmitters of zoonotic diseases. In this study, we identified a new CHPV in bat samples from the municipality of Santarém (Pará state, North Brazil). A total of 18 Molossus molossus bats were analyzed using viral metagenomics. In five animals, we identified CHPVs. These CHPV sequences presented the genome with a size ranging from 3797 to 4284 bp. Phylogenetic analysis-based nucleotide and amino acid sequences of the VP1 and NS1 regions showed that all CHPV sequences are monophyletic. They are also closely related to CHPV sequences previously identified in bats in southern and southeast Brazil. According to the International Committee on Taxonomy of Viruses (ICTV) classification criteria for this species (the CHPV NS1 gene region must have 85% identity to be classified in the same species), our sequences are likely a new specie within the genus Chaphamaparvovirus, since they have less than 80% identity with other CHPV described earlier in bats. We also make some phylogenetic considerations about the interaction between CHPV and their host. We suggest a high level of specificity of CPHV and its hosts. Thus, the findings contribute to improving information about the viral diversity of parvoviruses and show the importance of better investigating bats, considering that they harbor a variety of viruses that may favor zoonotic events.


Assuntos
Quirópteros , Parvovirus , Animais , Filogenia , Brasil/epidemiologia , Mamíferos
13.
Mini Rev Med Chem ; 23(2): 187-191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35692143

RESUMO

Chitin and chitosan have unique structures with significant functional groups carrying useful chemical capabilities. Chitin and chitosan are acknowledged as novel biomaterials with advantageous biocompatibility and biodegradability. Chitosan is a polysaccharide that is made from chitin. There have been several attempts to employ this biopolymer in the biomedical area. This material's application in the production of artificial skin, drug targeting, and other areas is explored. The most prevalent strategies for recovering chitin from sea organisms are described and various pharmacological and biological uses are discussed. This review article targets drug delivery with the help of chitosan derived nanomaterial. The drug delivery system applications through nonmaterial have encountered a considerable role in the pharmaceutical, medical, biological, and other sectors in recent years. Nanomaterials have advanced applications as novel drug delivery systems in many fields, especially in industry, biology, and medicine. In the biomedical and pharmaceutical arena, the natural polymer-based nanoparticulate method has now been widely studied as particulate vehicles. By mixing alginate with other biopolymers, by immobilizing specific molecules such as sugar molecules and peptides by chemical or physical cross-linking, different properties and structures such as biodegradability, gelling properties, mechanical strength, and cell affinity can be obtained. Owing to their inherent ability to deliver both hydrophilic and hydrophobic drug molecules, increase stability, decrease toxicity, and enhance commonly formulated medications, these particles are now widely used in imaging and molecular diagnostics, cosmetics, household chemicals, sunscreens, radiation safety, and novel drug delivery.


Assuntos
Quitosana , Quitosana/química , Sistemas de Liberação de Medicamentos , Quitina/química , Materiais Biocompatíveis/química , Preparações Farmacêuticas
14.
Virus Genes ; 59(1): 167-172, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36394716

RESUMO

The totiviridae family contains viruses with double-stranded RNA genomes of 4.6-7.0 kpb, which encode a capsid protein (CP) and RNA-dependent RNA polymerase (RdRp), and they are approximately 40 nm in diameter with icosahedral symmetry. Totiviruses were first isolated from mosquitoes collected in Shaanxi Province (China). Here, we report a new Aedes aegypti Totivirus (AaTV) identified in mosquitoes from the Amazon rainforest. Mosquitoes (Diptera: Culicidae) were collected from a forest reserve belonging to the Amazon forest in the city of Macapá, Amapá state, Northern Brazil. A viral sequence with a 5748 nucleotide length that was nearly identical to Aedes aegypti Totivirus (AaTV), here named Aedes aegypti Totivirus BR59AP, was detected. A detailed molecular analysis was performed and shows that AaTV-BR59AP is highly related to the AaTV strain from the Caribbean region. We emphasize the importance of the characterization of new viruses in mosquitoes to deepen our understanding of viral diversity in insects and their potential role in disease.


Assuntos
Aedes , Totiviridae , Totivirus , Vírus , Animais , Totivirus/genética , Brasil , Totiviridae/genética
15.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1521578

RESUMO

ABSTRACT Leishmania infantum is a protozoan that causes visceral leishmaniasis (VL) in the Americas and some regions of Europe. The disease is mainly characterized by hepatosplenomegaly and fever, and can be fatal. Factors related to the host and parasite can contribute to the transmission of Leishmania and the clinical outcome. The intraspecific genetic variability of L. infantum strains may be one of these factors. In this study, we evaluated the genetic variability of L. infantum obtained from bone marrow smear slides from patients in the Sao Paulo State, Brazil. For this, the minicircle of the kDNA hypervariable region was used as target by Sanger sequencing. By analyzing the similarity of the nucleotides and the maximum likelihood tree (Fasttree), we observed a high similarity (98%) among samples. Moreover, we identified four different profiles of L. infantum. In conclusion, L. infantum strains from Sao Paulo State, Brazil, showed low diversity measured by minicircle of the kDNA hypervariable region.

16.
Microorganisms ; 12(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38257846

RESUMO

Metagenomic next-generation sequencing (mNGS) methodology serves as an excellent supplement in cases where diagnosis is challenging to establish through conventional laboratory tests, and its usage is increasingly prevalent. Examining the causes of infectious diseases in the central nervous system (CNS) is vital for understanding their spread, managing outbreaks, and effective patient care. In a study conducted in the state of São Paulo, Brazil, cerebrospinal fluid (CSF) samples from 500 patients with CNS diseases of indeterminate etiology, collected between 2017 and 2021, were analyzed. Employing a mNGS approach, we obtained the complete coding sequence of Pegivirus hominis (HPgV) genotype 2 in a sample from a patient with encephalitis (named IAL-425/BRA/SP/2019); no other pathogen was detected. Subsequently, to determine the extent of this virus's presence, both polymerase chain reaction (PCR) and/or real-time PCR assays were utilized on the entire collection. The presence of the virus was identified in 4.0% of the samples analyzed. This research constitutes the first report of HPgV detection in CSF samples in South America. Analysis of the IAL-425 genome (9107 nt) revealed a 90% nucleotide identity with HPgV strains from various countries. Evolutionary analyses suggest that HPgV is both endemic and extensively distributed. The direct involvement of HPgV in CNS infections in these patients remains uncertain.

17.
Viruses ; 14(11)2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36366565

RESUMO

The genus totivirus in the family Totiviridae contains double-stranded RNA viruses. Their genome has two open reading frames (ORFs) that encode capsid protein (CP) and RNA-dependent RNA polymerase (RdRp). The toti-like viruses recently identified in Anopheles sp. and Aedes aegypti mosquitoes (AaTV) share the same genome organization as other totiviruses. The AaTVs that have been described in distinct geographical regions are monophyletic. In this study, we show that AaTV sequences can be grouped into at least three phylogenetic clades (named A, B, and C). Clades A and B are composed of AaTV sequences from mosquitoes collected in the Caribbean region (Guadeloupe), and clade C contains sequences from the USA. These clades may represent AaTV lineages that are locally adapted to their host populations. We also identified three recombinant AaTV strains circulating in mosquitoes in Guadeloupe. Although these strains have different chimeric patterns, the position of the recombination breakpoint was identical in all strains. Interestingly, this breakpoint is located in a hairpin-like structure in the intergenic region of the AaTV genome. This RNA structure may stall RNA polymerase processivity and consequently induce template switching. In vitro studies should be conducted to further investigate the biological significance of AaTV's intergenic region as a recombination hotspot.


Assuntos
Aedes , Totiviridae , Totivirus , Animais , Totivirus/genética , Aedes/genética , Filogenia , Genoma Viral , DNA Intergênico/genética , RNA Viral/genética , Totiviridae/genética , Fases de Leitura Aberta , Recombinação Genética
18.
J Water Health ; 20(2): 471-490, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36366999

RESUMO

The current COVID-19 pandemic has emphasized the vulnerability of communities living in the urban outskirts and informal settlements. The lack of reliable COVID-19 case data highlights the importance and application of wastewater-based epidemiology. This study aimed to monitor the COVID-19 trends in four vulnerable urban communities (slums and low-income neighborhoods) in metropolitan São Paulo by assessing the SARS-CoV-2 RNA viral load in wastewater. We analyzed 160 samples from May 2020 to June 2021 with weekly or fortnightly samplings. The samples were ultracentrifuged with glycine elution and quantified by N1/N2 SARS-CoV-2 RT-qPCR. The results of positivity were 100% (Paraisópolis, Heliópolis and Cidade Tiradentes) and 76.9% (Vila Brasilândia). The new case numbers of COVID-19, counted from the onset of symptoms, positively correlated with SARS-CoV-2 N1 viral loads from the two largest communities (p<0.001). SARS-CoV-2 infectivity was tested in Vero E6 cells after concentration with the two techniques, ultrafiltration (Centricon® Plus-70 10 kDa) and sucrose cushion ultracentrifugation, but none of the evaluated samples presented positive results. Next-generation sequencing (NGS) analysis from samples collected in March and August 2021 revealed the presence of the clade 20 J (lineage P.1) belonging to the most prevalent circulating variant in the country. Our results showed that wastewater surveillance data can be used as complementary indicators to monitor the dynamics and temporal trends of COVID-19. The infectivity test results strengthened the evidence of low risk of infection associated with SARS-CoV-2 in wastewater.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Águas Residuárias , Pandemias , COVID-19/epidemiologia , RNA Viral , Brasil/epidemiologia , Vigilância Epidemiológica Baseada em Águas Residuárias
19.
Antibiotics (Basel) ; 11(11)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36358126

RESUMO

Since the discovery of antibiotics in the 20th century, they have been used to fight against infections. The overuse of antibiotics in the wider environment has resulted in the emergence of multidrug-resistant bacteria. In developing countries such as China and developed countries such as the USA, there is evidence of the high pervasiveness of antibiotic-resistant infections. However, the studies on the spread of antibiotic-resistant microorganisms that inform about the consequences are limited. The aim of our study was to analyze and compare antimicrobial resistance (AMR) identified in published research papers from that found in different food sources, which were published between 2012 and December 2021, covering most retail food items. Out of 132 research papers identified, 26 papers have met our strict criteria and are included in the qualitative and quantitative analysis. The selected papers led to 13,018 food samples, out of which 5000 samples were contaminated, including 2276 and 2724 samples from China and the USA, respectively. Meat, aquatic products, milk, and eggs show high to medium potential for AMR exposure to Gram-positive bacteria such as Staphylococcus, Enterococci, etc. and Gram-negative foodborne pathogens such as Campylobacter, Salmonella, Vibrio, etc. Most of the food samples show antibiotic resistance to ß-lactams, tetracycline, quinolones, and aminoglycosides. Retail food products such as meat, sea food, and some other food products, as well as AMR genetics and technically important bacteria, are proposed to be better merged with mitigation strategies and systematic One Health AMR surveillance to minimize the knowledge gaps and facilitate comprehensive AMR risk computation for the consumers.

20.
PLoS One ; 17(9): e0272067, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36067165

RESUMO

Circular single stranded DNA viruses (CRESS DNA) encoding a homologous replication-associated protein (REP) have been identified in most of eukaryotic groups. It is not clear yet the role in human diseases or details of the life cycle of these viruses. Recently, much interest has been raised in the evolutionary history of CRESS DNA owing to the increasing number of new sequences obtained by Next-Generation Sequencing (NGS) in distinct host species. In this study we describe two full-length CRESS DNA genomes obtained of two newly diagnosed HIV patients from São Paulo State, Brazil. The initial BLASTx search indicated that both sequences (named SP-FFB/2020 and SP-MJMS/2020) are highly similar (98%) to a previous CRESS DNA sequence detected in human fecal sample from Peru in 2016 and designated as pecovirus (Peruvian stool-associated circo-like virus). This study reported for the first time the Human feces pecovirus in the feces of two newly diagnosed HIV patients in Brazil. Our comparative analysis showed that although pecoviruses in South America share an identical genome structure they diverge and form distinct clades. Thus, we suggest the circulation of different species of pecoviruses in Latin America. Nevertheless, further studies must be done to examine the pathogenicity of this virus.


Assuntos
Genoma Viral , Infecções por HIV , Brasil/epidemiologia , Vírus de DNA/genética , DNA de Cadeia Simples , DNA Viral/genética , Fezes , Genoma Viral/genética , Infecções por HIV/genética , Humanos , Filogenia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...