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1.
Sci Adv ; 9(35): eadg9204, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37656782

RESUMO

Despite the considerable morbidity and mortality of yellow fever virus (YFV) infections in Brazil, our understanding of disease outbreaks is hampered by limited viral genomic data. Here, through a combination of phylogenetic and epidemiological models, we reconstructed the recent transmission history of YFV within different epidemic seasons in Brazil. A suitability index based on the highly domesticated Aedes aegypti was able to capture the seasonality of reported human infections. Spatial modeling revealed spatial hotspots with both past reporting and low vaccination coverage, which coincided with many of the largest urban centers in the Southeast. Phylodynamic analysis unraveled the circulation of three distinct lineages and provided proof of the directionality of a known spatial corridor that connects the endemic North with the extra-Amazonian basin. This study illustrates that genomics linked with eco-epidemiology can provide new insights into the landscape of YFV transmission, augmenting traditional approaches to infectious disease surveillance and control.


Assuntos
Febre Amarela , Vírus da Febre Amarela , Humanos , Vírus da Febre Amarela/genética , Filogenia , Brasil/epidemiologia , Febre Amarela/epidemiologia , Surtos de Doenças , Genômica
2.
Indian J Med Res ; 157(4): 293-303, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37102510

RESUMO

Background & objectives: During the COVID-19 pandemic, the death rate was reportedly 5-8 fold lower in India which is densely populated as compared to less populated western countries. The aim of this study was to investigate whether dietary habits were associated with the variations in COVID-19 severity and deaths between western and Indian population at the nutrigenomics level. Methods: In this study nutrigenomics approach was applied. Blood transcriptome of severe COVID-19 patients from three western countries (showing high fatality) and two datasets from Indian patients were used. Gene set enrichment analyses were performed for pathways, metabolites, nutrients, etc., and compared for western and Indian samples to identify the food- and nutrient-related factors, which may be associated with COVID-19 severity. Data on the daily consumption of twelve key food components across four countries were collected and a correlation between nutrigenomics analyses and per capita daily dietary intake was investigated. Results: Distinct dietary habits of Indians were observed, which may be associated with low death rate from COVID-19. Increased consumption of red meat, dairy products and processed foods by western populations may increase the severity and death rate by activating cytokine storm-related pathways, intussusceptive angiogenesis, hypercapnia and enhancing blood glucose levels due to high contents of sphingolipids, palmitic acid and byproducts such as CO2 and lipopolysaccharide (LPS). Palmitic acid also induces ACE2 expression and increases the infection rate. Coffee and alcohol that are highly consumed in western countries may increase the severity and death rates from COVID-19 by deregulating blood iron, zinc and triglyceride levels. The components of Indian diets maintain high iron and zinc concentrations in blood and rich fibre in their foods may prevent CO2 and LPS-mediated COVID-19 severity. Regular consumption of tea by Indians maintains high high-density lipoprotein (HDL) and low triglyceride in blood as catechins in tea act as natural atorvastatin. Importantly, regular consumption of turmeric in daily food by Indians maintains strong immunity and curcumin in turmeric may prevent pathways and mechanisms associated with SARS-CoV-2 infection and COVID-19 severity and lowered the death rate. Interpretation & conclusions: Our results suggest that Indian food components suppress cytokine storm and various other severity related pathways of COVID-19 and may have a role in lowering severity and death rates from COVID-19 in India as compared to western populations. However, large multi-centered case-control studies are required to support our current findings.


Assuntos
COVID-19 , Ingredientes de Alimentos , Humanos , Nutrigenômica , Dióxido de Carbono , Lipopolissacarídeos , Pandemias , Síndrome da Liberação de Citocina , Ácido Palmítico , SARS-CoV-2 , Dieta/métodos , Comportamento Alimentar , Zinco , Chá , Ferro , Triglicerídeos
3.
J Fungi (Basel) ; 9(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675931

RESUMO

Ophiocordyceps australis (Ascomycota, Hypocreales, Ophiocordycipitaceae) is a classic entomopathogenic fungus that parasitizes ants (Hymenoptera, Ponerinae, Ponerini). Nonetheless, according to our results, this fungal species also exhibits a complete set of genes coding for plant cell wall degrading Carbohydrate-Active enZymes (CAZymes), enabling a full endophytic stage and, consequently, its dual ability to both parasitize insects and live inside plant tissue. The main objective of our study was the sequencing and full characterization of the genome of the fungal strain of O. australis (CCMB661) and its predicted secretome. The assembled genome had a total length of 30.31 Mb, N50 of 92.624 bp, GC content of 46.36%, and 8,043 protein-coding genes, 175 of which encoded CAZymes. In addition, the primary genes encoding proteins and critical enzymes during the infection process and those responsible for the host-pathogen interaction have been identified, including proteases (Pr1, Pr4), aminopeptidases, chitinases (Cht2), adhesins, lectins, lipases, and behavioral manipulators, such as enterotoxins, Protein Tyrosine Phosphatases (PTPs), and Glycoside Hydrolases (GHs). Our findings indicate that the presence of genes coding for Mad2 and GHs in O. australis may facilitate the infection process in plants, suggesting interkingdom colonization. Furthermore, our study elucidated the pathogenicity mechanisms for this Ophiocordyceps species, which still is scarcely studied.

5.
Vaccines (Basel) ; 10(3)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35334975

RESUMO

One hundred years after the flu pandemic of 1918, the world faces an outbreak of a new severe acute respiratory syndrome, caused by a novel coronavirus. With a high transmissibility, the pandemic has spread worldwide, creating a scenario of devastation in many countries. By the middle of 2021, about 3% of the world population had been infected and more than 4 million people had died. Different from the H1N1 pandemic, which had a deadly wave and ceased, the new disease is maintained by successive waves, mainly produced by new virus variants and the small number of vaccinated people. In the present work, we create a version of the SIR model using the spatial localization of persons, their movements, and considering social isolation probabilities. We discuss the effects of virus variants, and the role of vaccination rate in the pandemic dynamics. We show that, unless a global vaccination is implemented, we will have continuous waves of infections.

7.
Landsc Urban Plan ; 216: None, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34675450

RESUMO

Being a Re-Emerging Infectious Disease, dengue causes 390 million cases globally and is prevalent in many urban areas in South America. Understanding the fine-scale relationships between dengue incidence and environmental and socioeconomic factors can guide improved disease prevention strategies. This ecological study examines the association between dengue incidence and satellite-based vegetation greenness in 3826 census tracts nested in 474 neighborhoods in Belo Horizonte, Brazil, during the 2010 dengue epidemic. To reduce potential bias in the estimated dengue-greenness association, we adjusted for socioeconomic vulnerability, population density, building height and density, land cover composition, elevation, weather patterns, and neighborhood random effects. We found that vegetation greenness was negatively associated with dengue incidence in a univariate model, and this association attenuated after controlling for additional covariates. The dengue-greenness association was modified by socioeconomic vulnerability: while a positive association was observed in the least vulnerable census tracts, the association was negative in the most vulnerable areas. Using greenness as a proxy for vegetation quality, our results show the potential of vegetation management in reducing dengue incidence, particularly in socioeconomically vulnerable areas. We also discuss the role of water infrastructure, sanitation services, and tree cover in lowering dengue risk.

8.
J Med Entomol ; 58(1): 333-342, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-32785582

RESUMO

We provide the first evidence of a recent invasion of Aedes aegypti (Linnaeus in Hasselquist, 1762) and Aedes albopictus (Skuse 1894), followed by dengue virus, in tropical montane cities in south-eastern Brazil, Mariana, and Ouro Preto, at mid and high altitudes, respectively. Long-term temperature variation, dengue public data, and sampling of immature and adult mosquitoes (ovitraps and mosquitraps) in contrasting habitats were used to explain the distribution of Aedes in what in these two cities. From 1961 to 2014, the annual temperature increased significantly due to increases in winter temperatures. In the 1990s/2000s, the winter temperature was 1.3°C warmer than in the 1960s, when it varied from 21.2 to 18.9°C. After 2007, the winter temperatures increased and ranged from 21.6 to 21.3°C. The first autochthonous dengue cases in Mariana and Ouro Preto were in 2007, followed by few occurrences until in 2012, when the mean numbers increased three-fold, and peak at 2013. The continuous 'warmer winter' may have trigged the Aedes invasion. Aedes species benefited from higher winter temperatures, which was an important driver of their invasion of the state of Minas Gerais in the 1980s and, more recently, in the remaining montane urban habitats in this region. In both 2009 and 2011, we found more Aedes in Mariana than Ouro Preto, and more Ae. albopictus in green areas and Ae. aegypti in houses, the expected pattern for well-established populations.


Assuntos
Aedes/fisiologia , Distribuição Animal , Ecossistema , Tempo (Meteorologia) , Aedes/crescimento & desenvolvimento , Altitude , Animais , Brasil , Cidades , Clima , Larva/crescimento & desenvolvimento , Larva/fisiologia , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Estações do Ano
9.
PeerJ ; 8: e9446, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617196

RESUMO

BACKGROUND: We investigated a likely scenario of COVID-19 spreading in Brazil through the complex airport network of the country, for the 90 days after the first national occurrence of the disease. After the confirmation of the first imported cases, the lack of a proper airport entrance control resulted in the infection spreading in a manner directly proportional to the amount of flights reaching each city, following the first occurrence of the virus coming from abroad. METHODOLOGY: We developed a Susceptible-Infected-Recovered model divided in a metapopulation structure, where cities with airports were demes connected by the number of flights. Subsequently, we further explored the role of the Manaus airport for a rapid entrance of the pandemic into indigenous territories situated in remote places of the Amazon region. RESULTS: The expansion of the SARS-CoV-2 virus between cities was fast, directly proportional to the city closeness centrality within the Brazilian air transportation network. There was a clear pattern in the expansion of the pandemic, with a stiff exponential expansion of cases for all the cities. The more a city showed closeness centrality, the greater was its vulnerability to SARS-CoV-2. CONCLUSIONS: We discussed the weak pandemic control performance of Brazil in comparison with other tropical, developing countries, namely India and Nigeria. Finally, we proposed measures for containing virus spreading taking into consideration the scenario of high poverty.

10.
J Anim Ecol ; 89(8): 1754-1765, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32198927

RESUMO

Traditionally, most studies have described the organization of host-parasite interaction networks by considering only few host groups at limited geographical extents. However, host-parasite relationships are merged within different taxonomic groups and factors shaping these interactions likely differ between host and parasite groups, making group-level differences important to better understand the ecological and evolutionary dynamics of these interactive communities. Here we used a dataset of 629 ectoparasite species and 251 species of terrestrial mammals, comprising 10 orders distributed across the Nearctic and Neotropical regions of Mexico to assess the species-level drivers of mammalian ectoparasite faunas. Specifically, we evaluated whether body weight, geographical range size and within-range mammal species richness (i.e. diversity field) predict mammal ectoparasite species richness (i.e. degree centrality) and their closeness centrality within the mammal-ectoparasite network. In addition, we also tested if the observed patterns differ among mammal orders and if taxonomic closely related host mammals could more likely share the same set of ectoparasites. We found that ectoparasite species richness of small mammals (mainly rodents) with large proportional range sizes was high compared to large-bodied mammals, whereas the diversity field of mammals had no predictive value (except for bats). We also observed that taxonomic proximity was a main determinant of the probability to share ectoparasite species. Specifically, the probability to share ectoparasites in congeneric species reached up to 90% and decreased exponentially as the taxonomic distance increased. Further, we also detected that some ectoparasites are generalists and capable to infect mammalian species across different orders and that rodents have a remarkable role in the network structure, being closely connected to many other taxa. Hence, because many rodent species have synanthropic habits they could act as undesired reservoirs of disease agents for humans and urban animals. Considering the reported worldwide phenomenon of the proliferation of rodents accompanying the demographic decrease or even local extinction of large-bodied mammal species, these organisms may already be an increasing health threat in many regions of the world.


Assuntos
Ectoparasitoses , Parasitos , Doenças dos Roedores , Animais , Ectoparasitoses/veterinária , Interações Hospedeiro-Parasita , Mamíferos , México , Doenças dos Roedores/epidemiologia , Roedores
11.
Ecology ; 99(12): 2875, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30380155

RESUMO

Butterflies are one of the best-known insect groups, and they have been the subject of numerous studies in ecology and evolution, especially in the tropics. Much attention has been given to the fruit-feeding butterfly guild in biodiversity conservation studies, due to the relative ease with which taxa may be identified and specimens sampled using bait traps. However, there remain many uncertainties about the macroecological and biogeographical patterns of butterflies in tropical ecosystems. In the present study, we gathered information about fruit-feeding butterfly species in local communities from the Atlantic Forests of South America. The ATLANTIC BUTTERFLIES data set, which is part of ATLANTIC SERIES data papers, results from a compilation of 145 unpublished inventories and 64 other references, including articles, theses, and book chapters published from 1949 to 2018. In total, the data set contains 7,062 records (presence) of 279 species of fruit-feeding butterflies identified with taxonomic certainty, from 122 study locations. The Satyrini is the tribe with highest number of species (45%) and records (30%), followed by Brassolini, with 13% of species and 12.5% of records. The 10 most common species correspond to 14.2% of all records. This data set represents a major effort to compile inventories of fruit-feeding butterfly communities, filling a knowledge gap about the diversity and distribution of these butterflies in the Atlantic Forest. We hope that the present data set can provide guidelines for future studies and planning of new inventories of fruit-feeding butterflies in this biome. The information presented here also has potential use in studies across a great variety of spatial scales, from local and landscape levels to macroecological research and biogeographical research. We expect that such studies be very important for the better implementation of conservation initiatives, and for understanding the multiple ecological processes that involve fruit-feeding butterflies as biological indicators. No copyright restrictions apply to the use of this data set. Please cite this Data paper when using the current data in publications or teaching events.

12.
Mem. Inst. Oswaldo Cruz ; 110(5): 669-676, Aug. 2015. ilus
Artigo em Inglês | LILACS | ID: lil-755905

RESUMO

Despite the importance of the mosquito Aedes aegypti in the transmission of arboviruses, such as yellow fever, Chikungunya fever and dengue fever, some aspects of their behaviour remain unknown. In the present study, the oviposition behaviour of Ae. aegypti females that were exposed to different densities of breeding sites (2, 4, 8 and 16) was evaluated in laboratory and semi-field conditions. The number of breeding sites that were used was proportional to the number available, but tended towards stabilisation. Females used four-six breeding sites on average, with a maximum of 11. A high percentage of eggs was observed in the water, along with the presence of a breeding site termed “favourite”, which received at least 40% of the eggs. The results are discussed in ecological, evolutionary and epidemiological approaches.

.


Assuntos
Animais , Feminino , Aedes/anatomia & histologia , Cruzamento , Comportamento Animal/fisiologia , Insetos Vetores/fisiologia , Oviposição/fisiologia
13.
Mem Inst Oswaldo Cruz ; 110(5): 669-76, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26154742

RESUMO

Despite the importance of the mosquito Aedes aegypti in the transmission of arboviruses, such as yellow fever, Chikungunya fever and dengue fever, some aspects of their behaviour remain unknown. In the present study, the oviposition behaviour of Ae. aegypti females that were exposed to different densities of breeding sites (2, 4, 8 and 16) was evaluated in laboratory and semi-field conditions. The number of breeding sites that were used was proportional to the number available, but tended towards stabilisation. Females used four-six breeding sites on average, with a maximum of 11. A high percentage of eggs was observed in the water, along with the presence of a breeding site termed "favourite", which received at least 40% of the eggs. The results are discussed in ecological, evolutionary and epidemiological approaches.


Assuntos
Aedes/anatomia & histologia , Comportamento Animal/fisiologia , Cruzamento , Insetos Vetores/fisiologia , Oviposição/fisiologia , Animais , Feminino
14.
Braz. arch. biol. technol ; 48(2): 275-284, Mar. 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-398040

RESUMO

Duas populações de Mabea fistulifera (Euphorbiaceae) localizadas no Parque Estadual do Rio Doce (Minas Gerais, Brasil), mas em locais caracterizados como em diferentes estágios sucessionais, foram investigadas quanto a parâmetros genéticos e ecológicos. Em cada população, 20 indivíduos escolhidos de forma aleatória, foram avaliados quanto à presença de 43 marcadores RAPD, cinco características morfológicas e quanto à distribuição espacial. O índice de Shannon e a AMOVA revelaram que a maior parte da variação genética está localizada entre indivíduos dentro das populações, com apenas cerca de 9% da variação entre populações. As populações diferem geneticamente, mas possuem valores similares de diversidade genética. Os dados morfológicos revelaram marcantes diferenças entre as populações. Foram obtidas correlações significativas entre matrizes de distâncias genéticas, geográficas e morfológicas, considerando-se ambas as populações. Os dados revelaram ainda que dentro de uma mesma população, indivíduos espacialmente mais próximos tendem a ser mais semelhantes geneticamente. Os resultados são discutidos a respeito da biologia da espécie e das características das populações.

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