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1.
MHSalud ; 21(1): 50-66, ene.-jun. 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558385

RESUMO

Abstract: Introduction: The variables determinants of physical performance in cross-country marathon of mountain biking (XCMMTB) are still unknown. Objective: We aimed to verify the training control variables and the physiological responses in an official XCM-MTB race. Material and methods: 13 athletes (11 men and 2 women; 33.3 ± 12.7 years of age) participated in this study. It was conducted during an official XCM-MTB in Brazil (route of 70 km). The heart rate (HR), altimetry, velocity, temperature, pacing, and power were obtained every 10 km travelled by the STRAVA application. Multiple linear regression analysis was performed to verify whether the variables could predict physical performance. Results: The athletes maintained constant HR elevation in the corresponding zone 80% HRmax. They also presented a variation in the pacing (F = 35.82; p < 0.001; d = 0.66) and power (F = 7.20; p < 0.001; d = 0.18) showing higher values in the last 10 km. Only pacing can be considered a predictor of the physical performance (β = 0.958; t = 7.30; p < 0.001), specifically the one at 20 km (F = 10.23; p = 0.004; R2 = 0.82). Conclusion: The study concluded that the analyzed variables are reliable for the performance control in an official XCMMTB race. HR and power are variables that can be used to prescribe and control training, as they change according to the requirements of the race. Power can also be used as a performance predictor as it is directly influenced by terrain.


Resumen: Introducción: Las variables determinantes del rendimiento físico en una maratón de ciclismo de montaña (XCM-MTB) aún son desconocidas. Objetivo: Nuestro objetivo fue verificar las variables fisiológicas y de control del entrenamiento en una carrera oficial de XCM-MTB. Materiales y métodos: 13 atletas (11 hombres y 2 mujeres; 33,3 ± 12,7 años) participaron en este estudio. La investigación se realizó durante un XCM-MTB oficial en Brasil (recorrido de 70 km). La frecuencia cardíaca (FC), la altimetría, la velocidad, la temperatura, el ritmo y la potencia se obtuvieron cada 10 km recorridos por la aplicación STRAVA. Se realizó un análisis múltiple de regresión linear para verificar si las variables podían predecir el rendimiento físico. Resultados: Hubo una elevación constante de la FC correspondiente al 80 % de la FCmax. El ritmo presentó una variación (F = 35,82; p < 0,001; d = 0,66) y potencia (F = 7,20; p < 0,001; d = 0,18) con valores superiores en los últimos 10 km. Solo el ritmo a los 20 km (F = 10,23; p = 0,004; R2 = 0,82) puede considerarse predictor del rendimiento físico (β = 0,958; t = 7,30; p < 0,001). Conclusión: El estudio concluyó que las variables analizadas son fiables para la prescripción y control del entrenamiento en una carrera oficial de XCM-MTB. La FC y la potencia son variables que se pueden utilizar para prescribir el entrenamiento. La potencia también se puede utilizar para predecir el rendimiento, ya que está directamente influenciada por el terreno.


Resumo: Introdução: As variáveis determinantes do desempenho físico na maratona de mountain bike cross-country (XCMMTB) ainda são desconhecidas. Objetivo: Nosso objetivo foi verificar as variáveis de controle de treinamento e as respostas fisiológicas em uma corrida oficial de XCMMTB. Material e métodos: Participaram deste estudo 13 atletas (11 homens e 2 mulheres; 33,3 ± 12,7 anos de idade). O estudo foi realizado durante uma corrida oficial de XCM-MTB no Brasil (percurso de 70 km). A frequência cardíaca (FC), altimetria, velocidade, temperatura, ritmo e potência foram obtidos a cada 10 km percorridos através do aplicativo STRAVA. Foi realizada uma análise de regressão linear múltipla para verificar se as variáveis poderiam prever o desempenho físico. Resultados: Os atletas mantiveram uma elevação constante na FC na zona correspondente a 80% da FC máxima. Apresentaram também variação no ritmo (F = 35,82; p < 0,001; d = 0,66) e na potência (F = 7,20; p < 0,001; d = 0,18), mostrando valores mais altos nos últimos 10 km. Apenas o ritmo pode ser considerado um preditor do desempenho físico (β = 0,958; t = 7,30; p < 0,001), especificamente no ponto dos 20 km (F = 10,23; p = 0,004; R2 = 0,82). Conclusão: O estudo concluiu que as variáveis analisadas são confiáveis para o controle de desempenho em uma corrida oficial de XCMMTB. A FC e a potência são variáveis que podem ser usadas para prescrever e controlar o treinamento, pois mudam de acordo com as exigências da corrida. A potência também pode ser usada como um preditor de desempenho, pois é diretamente influenciada pelo terreno.

2.
Sci Rep ; 14(1): 14322, 2024 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907012

RESUMO

Organic production systems are increasingly gaining market share; however, there are still few studies on their influence on the activity of soil microorganisms in sugarcane. Arbuscular mycorrhizal fungi are extremely sensitive to environmental changes, and their activity can be used as a parameter of comparison and quality between organic and conventional systems. The objective of this work was to evaluate mycorrhizal activity in different varieties of sugarcane under two production systems. This work was carried out in a commercial plantation of the Jalles Machado plant in the municipality of Goianésia in Goiás, Brazil. The values of spore density in the soil, mycorrhizal colonization rate in the roots and easily extractable glomalin were evaluated, and the associated fungal species were identified. There was no effect of sugarcane variety on the number of spores or the glomalin content in the soil. The conventional system presented significantly lower mycorrhizal colonization rates than did the organic system. The varieties cultivated under the conventional planting system showed a greater diversity of arbuscular mycorrhizal fungi, where 12 of the 13 different species of mycorrhizal fungi found in both cultivation systems occurred.


Assuntos
Micorrizas , Saccharum , Microbiologia do Solo , Saccharum/microbiologia , Micorrizas/fisiologia , Brasil , Raízes de Plantas/microbiologia , Agricultura Orgânica , Solo/química , Glicoproteínas , Esporos Fúngicos , Proteínas Fúngicas
3.
Acta Trop ; 257: 107272, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885823

RESUMO

The Orthoflavivirus ilheusense (ILHV) is an arbovirus that was first isolated in Brazil in 1944 during an epidemiologic investigation of yellow fever. Is a member of the Flaviviridae family and it belongs to the antigenic complex of the Ntaya virus group. Psorophora ferox is the primary vector of ILHV and this study presents the isolation and phylogenetic analysis of ILHV in a pool of Ps. ferox collected in the state of Goiás in 2021. Viral isolation tests were performed on Vero cells and C6/36 clones. The indirect immunofluorescence test (IFI) was used to confirm the positivity of the sample. The positive sample underwent RT-qPCR, sequencing, and phylogenetic analysis. This is the first report of ILHV circulation in this municipality and presented close relationship between this isolate and another ILHV isolate collected in the city of Belém (PA).

4.
Int J Mol Sci ; 25(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38928410

RESUMO

Chikungunya virus (Togaviridae, Alphavirus; CHIKV) is a mosquito-borne global health threat. The main urban vector of CHIKV is the Aedes aegypti mosquito, which is found throughout Brazil. Therefore, it is important to carry out laboratory tests to assist in the virus's diagnosis and surveillance. Most molecular biology methodologies use nucleic acid extraction as the first step and require quality RNA for their execution. In this context, four RNA extraction protocols were evaluated in Ae. aegypti experimentally infected with CHIKV. Six pools were tested in triplicates (n = 18), each containing 1, 5, 10, 20, 30, or 40 mosquitoes per pool (72 tests). Four commercial kits were compared: QIAamp®, Maxwell®, PureLink®, and PureLink® with TRIzol®. The QIAamp® and PureLink® with TRIzol® kits had greater sensitivity. Two negative correlations were observed: as the number of mosquitoes per pool increases, the Ct value decreases, with a higher viral load. Significant differences were found when comparing the purity and concentration of RNA. The QIAamp® protocol performed better when it came to lower Ct values and higher RNA purity and concentration. These results may provide help in CHIKV entomovirological surveillance planning.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Mosquitos Vetores , RNA Viral , Vírus Chikungunya/isolamento & purificação , Vírus Chikungunya/genética , Aedes/virologia , Animais , RNA Viral/isolamento & purificação , RNA Viral/genética , Mosquitos Vetores/virologia , Febre de Chikungunya/virologia , Febre de Chikungunya/diagnóstico , Carga Viral/métodos
5.
An Acad Bras Cienc ; 96(2): e20230559, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747788

RESUMO

Creatine is consumed by athletes to increase strength and gain muscle. The aim of this study was to evaluate the effects of creatine supplementation on maximal strength and strength endurance. Twelve strength-trained men (25.2 ± 3.4 years) supplemented with 20 g Creatina + 10g maltodextrin or placebo (20g starch + 10g maltodextrin) for five days in randomized order. Maximal strength and strength endurance (4 sets 70% 1RM until concentric failure) were determined in the bench press. In addition, blood lactate, rate of perceived effort, fatigue index, and mood state were evaluated. All measurements were performed before and after the supplementation period. There were no significant changing in maximal strength, blood lactate, RPE, fatigue index, and mood state in either treatment. However, the creatine group performed more repetitions after the supplementation (Cr: Δ = +3.4 reps, p = 0.036, g = 0.53; PLA: Δ = +0.3reps, p = 0.414, g = 0.06), and higher total work (Cr: Δ = +199.5au, p = 0.038, g = 0.52; PLA: Δ = +26.7au, p = 0.402, g = 0.07). Creatine loading for five days allowed the subjects to perform more repetitions, resulting in greater total work, but failed to change the maximum strength.


Assuntos
Creatina , Suplementos Nutricionais , Ácido Láctico , Força Muscular , Resistência Física , Humanos , Masculino , Adulto , Creatina/administração & dosagem , Creatina/farmacologia , Creatina/sangue , Força Muscular/efeitos dos fármacos , Força Muscular/fisiologia , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Ácido Láctico/sangue , Adulto Jovem , Treinamento Resistido/métodos , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/fisiologia , Método Duplo-Cego
6.
Sci Rep ; 14(1): 7981, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38575654

RESUMO

Bats are efficient reservoirs of a number of viruses with zoonotic potential, and are involved directly in the transmission cycle of many zoonoses. In the present study, which is part of a larger project that is documenting the viromes of the bat species found in the Mid-North states of Maranhão and Piauí, we analyzed 16 pooled samples obtained from four species of bat of the genus Artibeus-Artibeus obscurus, Artibeus cinereus, Artibeus lituratus and Artibeus planirostris. We describe and identify a Hepatovirus, denominated Hepatovirus H isolate sotense, which was found in a pool of internal organs (liver and lungs) extracted from a specimen of A. planirostris, a frugivorous bat, collected in the Cerrado biome of Maranhão state. This material was analyzed using new generation sequencing, which produced a contig of 7390 nucleotides and presented a degree of identity with a number of existing Hepatovirus sequences available for bats (amino acid identity of 61.5% with Bat hepatovirus C of Miniopterus cf. manavi, 66.6% with Bat hepatovirus G of Coleura afra, 67.4% with Hepatovirus G2 of Rhinolophus landeri, and 75.3% with Hepatovirus H2 of Rhinolophus landeri). The analysis of the functional domains of this contig confirmed a pattern consistent with the characteristics of the genus Hepatovirus (Picornaviridae). In the phylogenetic tree with several other Hepatovirus species, this genome also grouped in a monophyletic clade with Hepatovirus H (HepV-H1; HepV-H2, and HepV-H3) albeit on an external branch, which suggests that it may be a distinct genotype within this species. This is the first isolate of Hepatovirus H identified in bats from South America, and represents an important discovery, given that most studies of viruses associated with bats in the state of Maranhão have focused on the family Rhabdoviridae.


Assuntos
Quirópteros , Animais , Brasil , Hepatovirus , Filogenia , Genômica
7.
Res Sports Med ; : 1-16, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38482841

RESUMO

The aim of this study was to evaluate the influence of sodium bicarbonate (SB) supplementation on physical performance, neuromuscular and metabolic responses during CrossFit® exercise. Seventeen Advanced CrossFit®-trained athletes completed the randomized, double-blind, placebo-controlled crossover protocol consisting of four visits, including two familiarization sessions and two experimental trials separated by a 7-day washout period. Participants supplemented 0.3 g/kg body mass (BM) of SB or placebo 120-min prior to performing the CrossFit® benchmark Fran followed by 500 m of rowing. SB improved time to complete Fran compared to PLA (291.2 ± 71.1 vs. 303.3 ± 77.8 s, p = 0.047), but not 500 m rowing (112.1 s ± 7.9 vs. 113.2 s ± 8.9 s, p = 0.26). No substantial side-effects were reported during the trials. This study showed that SB improved CrossFit® benchmark Fran performance, but not subsequent 500-m rowing. These data suggest that SB might be an interesting supplementation strategy for CrossFit® athletes.

8.
Microorganisms ; 12(3)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38543644

RESUMO

Bats are widely distributed in Brazil, including the Amazon region, and their association with viral pathogens is well-known. This work aimed to evaluate the metavirome in samples of Molossus sp. bats captured in the Brazilian Amazon from 2019 to 2021. Lung samples from 58 bats were divided into 13 pools for RNA isolation and sequencing followed by bioinformatic analysis. The Retroviridae family showed the highest abundance of viral reads. Although no complete genome could be recovered, the Paramyxoviridae and Dicistroviridae families showed the formation of contigs with satisfactory identity and size characteristics for further analysis. One contig of the Paramyxoviridae family was characterized as belonging to the genus Morbillivirus, being grouped most closely phylogenetically to Porcine morbillivirus. The contig related to the Dicistroviridae family was identified within the Cripavirus genus, with 94%, 91%, and 42% amino acid identity with Culex dicistrovirus 2, Rhopalosiphum padi, and Aphid lethal paralysis, respectively. The presence of viruses in bats needs constant updating since the study was able to identify viral sequences related to families or genera still poorly described in the literature in association with bats.

9.
Sci Rep ; 14(1): 6346, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491115

RESUMO

Bats play an essential role in maintaining ecosystems. Their unique characteristics increase the likelihood of interactions with various species, making them a potential source for the emergence and spread of infectious diseases. Hantaviruses are continuously expanding their range of hosts. This study presents the identification of a partial genome associated with Hantavirus in samples collected from neotropical bats. We conducted a metagenomic study using samples from Carollia perspicillata in Maranhão, Brazil. Tissue fragments were used for RNA extraction and subsequent sequencing. The resulting data was subjected to bioinformatic analysis. A sequence showing an identity of 72.86% with the L gene in the reference genome was obtained. The phylogenetic analysis revealed the study sequence, denoted as Buritiense, clustering within the Mobatvirus clade. The intragroup analysis showed a broader dispersion and were markedly asymmetric. This observation suggests the possibility that Buritiense could potentially represent a new species within the bat-borne hantaviruses, but further analyses are needed to provide additional insights if bats plays a role as reservoirs and the potential for transmission to human populations.


Assuntos
Quirópteros , Orthohantavírus , Vírus de RNA , Animais , Brasil , Ecossistema , Orthohantavírus/genética , Filogenia
10.
Viruses ; 16(2)2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38399986

RESUMO

The Saint Louis encephalitis virus (SLEV) is an encephalitogenic arbovirus (Flaviviridae family) that has a wide geographical distribution in the western hemisphere, especially in the Americas. The negevirus Brejeira (BREV) was isolated for the first time in Brazil in 2005. This study aimed to verify the existence of a possible interfering effect of BREV on the course of SLEV infection and vice versa. We used clone C6/36 cells. Three combinations of MOIs were used (SLEV 0.1 × BREV 1; SLEV 1 × BREV 0.1; SLEV 1 × BREV 1) in the kinetics of up to 7 days and then the techniques of indirect immunofluorescence (IFA), a plaque assay on Vero cells, and RT-PCR were performed. Our results showed that the cytopathic effect (CPE) caused by BREV was more pronounced than the CPE caused by SLEV. Results of IFA, the plaque assay, and RT-PCR showed the suppression of SLEV replication in the co-infection condition in all the MOI combinations used. The SLEV suppression was dose-dependent. Therefore, the ISV Brejeira can suppress SLEV replication in Aedes albopictus cells, but SLEV does not negatively interfere with BREV replication.


Assuntos
Aedes , Vírus da Encefalite de St. Louis , Interferência Viral , Animais , Chlorocebus aethiops , Vírus da Encefalite de St. Louis/genética , Células Vero , Insetos
11.
BMC Genomics ; 25(1): 34, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177994

RESUMO

BACKGROUND: Bats are renowned for harboring a high viral diversity, their characteristics contribute to emerging infectious diseases. However, environmental and anthropic factors also play a significant role in the emergence of zoonotic viruses. Metagenomic is an important tool for investigating the virome of bats and discovering new viruses. RESULTS: Twenty-four families of virus were detected in lung samples by sequencing and bioinfomatic analysis, the largest amount of reads was focused on the Retroviridae and contigs assembled to Desmodus rotundus endogenous retrovirus, which was feasible to acquire complete sequences. The reads were also abundant for phages. CONCLUSION: This lung virome of D. rotundus contributes valuable information regarding the viral diversity found in bats, which is useful for understanding the drivers of viral cycles and their ecology in this species. The identification and taxonomic categorization of viruses hosted by bats carry epidemiological significance due to the potential for viral adaptation to other animals and humans, which can have severe repercussions for public health. Furthermore, the characterization of endogenized viruses helps to understanding the host genome and the evolution of the species.


Assuntos
Bacteriófagos , Quirópteros , Vírus , Animais , Quirópteros/virologia , Ecologia , Filogenia , Viroma/genética , Vírus/genética
12.
Trop Med Infect Dis ; 9(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38251214

RESUMO

Dengue virus serotype 2 (DENV-2) is responsible for dengue epidemics on a global scale and is associated with severe cases of the disease. This study conducted a phylogenetic investigation of DENV-2 isolates from 2017 to 2021 originating from the northern states of Brazil. A total of 32 samples from DENV-2 isolates were analyzed, including 12 from Acre, 19 from Roraima, and one from Tocantins. Only one lineage of the Asian-American genotype and one lineage of the cosmopolitan genotype were observed: Lineage 1, Asian-American genotype (connection to Puerto Rico); Lineage 5, cosmopolitan genotype (connection to Peru). Our results provide important data regarding the study of DENV genotypes and lineage distribution and open up possibilities for probable introduction and dissemination routes.

13.
Insects ; 14(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38132611

RESUMO

Aedes aegypti is a mosquito native to the African continent, which is now widespread in the tropical and subtropical regions of the world. In many regions, it represents a major challenge to public health, given its role in the cycle of transmission of important arboviruses, such as Dengue, Zika, and Chikungunya. Considering the epidemiological importance of Ae. aegypti, the present study sequenced the partial mitochondrial genome of a sample collected in the municipality of Balsas, in the Brazilian state of Maranhão, followed by High Throughput Sequencing and phylogenetic analyses. The mitochondrial sequence obtained here was 15,863 bp long, and contained 37 functional subunits (thirteen PCGs, twenty-two tRNAs and two rRNAs) in addition to a partial final portion rich in A+T. The data obtained here contribute to the enrichment of our knowledge of the taxonomy and evolutionary biology of this prominent disease vector. These findings represent an important advancement in the understanding of the characteristics of the populations of northeastern Brazil and provide valuable insights into the taxonomy and evolutionary biology of this prominent disease vector.

15.
Front Vet Sci ; 10: 1257558, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841469

RESUMO

Viruses of the Lyssavirus genus are classified into several genotypes (GT1 to GT7), of which only GT1 (classic rabies virus-RABV) has a cosmopolitan distribution and circulates in Brazil. GT1 is subdivided into several antigenic variants (AgV) maintained in independent cycles with a narrow host range and distinct geographic distributions, namely, AgV1 and AgV2 found in dogs, AgV3 in the vampire bats Desmodus rotundus, and AgV4 and AgV6 in bats non-hematophagous Tadarida brasiliensis and Lasiurus cinereus, a common variant of marmoset (Callithrix jacchus), and crab-eating fox (Cerdocyon thous). In this study, we performed phylogenetic analysis to identify at the antigenic variant level; six RABV genomes derived from the Rabies Surveillance in the north and northeast regions of Brazil. The analysis resulted in the formation of 11 monophyletic clusters, each corresponding to a particular variant, with high bootstrap support values. The samples were positioned inside the AgV3, AgV6, and Callithrix variant clades. This is the first report of the AgV6 variant found in northern Brazil, which provides valuable information for rabies surveillance in the country. The possibility of viral spillover has been much debated, as it deals with the risk of shifting transmission from a primary to a secondary host. However, more genomic surveillance studies should be performed, with a greater number and diversity of samples to better understand the transmission dynamics of each variant to detect changes in its geographic distribution and spillover events.

16.
Front Chem ; 11: 1267634, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795387

RESUMO

Introduction: The green revolution model that is followed in the Brazilian Cerrado is dependent on mechanization, chemical fertilization for soil dressing and correction, and the use of herbicides. Paraquat is a methyl viologen herbicide marketed as bipyridylium dichloride salts and used (in low doses) to combat weeds in their post-emergence stage. It is a non-selective pesticide that causes the peroxidation of the lipids that make up the cell membrane, and when it comes into contact with foliage, it results in the death of the plant. Methods: The effect of water molecules co-crystallized in Paraquat salt structures was analyzed in anhydrous, dihydrate, and trihydrate forms to understand those physicochemical properties in its redox activity. The frontier molecular orbitals were also carried out using DFT to obtain the chemical reactivity of the bipyridylium cation. Finally, the supramolecular arrangements were evaluated to analyze the physicochemical stability and acquire insights on superoxide anions. Results and discussion: The electronic structure indicated that the BP cation presents an acidic character due to its low ELUMO value, while the salt has a more basic character due to its high EHOMO value. For this reason, the BP ion is more susceptible to reduction during the weeds' photosynthesis process. During the process of plant photosynthesis, PQ is reduced to form a stable radical cation. In the supramolecular arrangement, the presence of water molecules increases the number of strong H-bonds, while the weak/moderate H-bonds are stabilized. PQ's toxic effects are observed in wildlife, domesticated animals, human populations, and ecosystems. The influence of PQ on the terrestrial environment is limited because of the soil adsorption capacity associated with good agricultural practices. The current use of good agricultural practices in the Cerrado seems not to prevent the environmental impacts of herbicides like PQ because it aims for the expansion and profitability of large-scale farming based on input-intensive practices instead of sustainable agriculture processes.

17.
Infect Genet Evol ; 113: 105487, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37544570

RESUMO

DENV-2 was the main responsible for a 70% increase in dengue incidence in Brazil during 2019. That year, our metagenomic study by Illumina NextSeq on serum samples from acute febrile patients (n = 92) with suspected arbovirus infection, sampled in 22 cities of the state of Mato Grosso (MT), in the middle west of Brazil, revealed eight complete genomes and two near-complete sequences of DENV-2 genotype III, one Human parvovirus B19 genotype I (5,391 nt) and one Coxsackievirus A6 lineage D (4,514 nt). These DENV-2 sequences share the aminoacidic identities of BR4 lineage on E protein domains I, II and III, and were included in a clade with sequences of the same lineage circulating in the southeast of Brazil in the same year. Nevertheless, 11/34 non-synonymous mutations are unique to three strains inthis study, distributed in the E (n = 6), NS3 (n = 2) and NS5 (n = 3) proteins. Other 14 aa changes on C (n = 1), E (n = 3), NS1 (n = 2), NS2A (n = 1) and NS5 (n = 7) were first reported in a genotype III lineage, having been already reported only in other DENV-2 genotypes. All 10 sequences have mutations in the NS5 protein (14 different aa changes). Nine E protein aa changes found in two sequences, six of which are unique, are in the ectodomain; where the E:M272T change is on the hinge of the E protein at domain II, in a region critical for the anchoring to the host cell receptor. The NS5:G81R mutation, in the methyltransferase domain, was found in one strain of this study. Altogether, these data points to an important evolution of DENV-2 genotype III lineage BR4 during this outbreak in 2019 in MT. Genomic surveillance is essential to detect virus etiology and evolution, possibly related to immune evasion and viral fitness changes leading to future novel outbreaks.


Assuntos
Vírus da Dengue , Dengue , Humanos , Vírus da Dengue/genética , Dengue/epidemiologia , Sorogrupo , Brasil/epidemiologia , Genótipo , Surtos de Doenças , Filogenia
18.
Genes (Basel) ; 14(7)2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37510347

RESUMO

A wide diversity of pathogenic mosquito-borne viruses circulate in the Brazilian Amazon, and the intense deforestation can contribute to the spread of these viruses. In this context, this study aimed to investigate the viral diversity in mosquitoes of the genera Aedes, Culex, Haemagogus, and Sabethes from a transition area between the Amazon, Cerrado, and Caatinga biomes in Brazil. Metagenomic high-throughput sequencing was used to characterize the virome of 20 mosquito pools. A total of 15 virus-like genomes were identified, comprising species genomically close to insect-specific viruses of the families Iflaviridae, Metaviridae, Lispiviridae, Rhabdoviridae, Xinmoviridae, and Parvoviridae and species of plant viruses of the families Solemoviridae, Virgaviridae, and Partitiviridae. However, sequences of viruses associated with human and animal diseases were not detected. Most of the recovered genomes were divergent from those previously described. These findings reveal that there are a large number of unknown viruses to be explored in the middle-north of Brazil.


Assuntos
Aedes , Culex , Vírus de RNA , Vírus , Animais , Humanos , Brasil , Ecossistema , Viroma
20.
Trop Med Infect Dis ; 8(6)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37368743

RESUMO

Dengue virus 2 (DENV-2) seriously contributes to dengue-related mortality. It includes five nonsylvatic genotypes, with cosmopolitan being the most widespread with a significant contribution to the total number of DENV-2 cases globally. In South America, the cosmopolitan genotype was first recorded in 2019 in Madre de Dios, Peru, and then in Goiás (Midwest Brazil) in November 2021. In this study, we tested 163 human serum samples from Acre (Northern Brazil) collected during a DENV outbreak between 2020 and 2021 for all DENV genotypes by RT-qPCR. Of the 163 samples, 139 were positive for DENV-2, and 5 were positive for DENV-1. Five DENV-2-positive samples from early 2021 were sequenced, and the sequences clustered with the three other DENV-2 cosmopolitan genotype sequences already recorded on the continent. These results create a geographical link, suggesting the possible route of introduction of the DENV-2 cosmopolitan genotype into Brazil through the border with Peru, from which it may have dispersed to Midwest Brazil.

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