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An Insight into the Chromosomal Evolution of Lebiasinidae (Teleostei, Characiformes)
Get PDFLebiasinidae fishes have been historically neglected by cytogenetical studies. Here we present a genomic comparison in eleven Lebiasinidae species, in addition to a review of the ribosomal DNA sequences distribution in this family. With that, we develop ten sets of experiments in order to hybridize the genomic DNA of representative species from the genus Copeina, Copella, Nannostomus, and Pyrrhulina in metaphase plates of Lebiasina melanoguttata. Two major pathways on the chromosomal evolution of these species can be recognized: (i) conservation of 2n = 36 bi-armed chromosomes in Lebiasininae, as a basal condition, and (ii) high numeric and structural chromosomal rearrangements in Pyrrhulininae, with a notable tendency towards acrocentrization. The ribosomal DNA (rDNA) distribution also revealed a marked differentiation during the chromosomal evolution of Lebiasinidae, since both single and multiple sites, in addition to a wide range of chromosomal locations can be found. With some few exceptions, the terminal position of 18S rDNA appears as a common feature in Lebiasinidae-analyzed species. Altogether with Ctenoluciidae, this pattern can be considered a symplesiomorphism for both families. In addition to the specific repetitive DNA content that characterizes the genome of each particular species, Lebiasina also keeps inter-specific repetitive sequences, thus reinforcing its proposed basal condition in Lebiasinidae
Poluição atmosférica na área urbana de Manaus: modelagem e aspectos observacionais de traçadores de queimada
No full textIn the Amazon region, severe droughts associated with climate change occurred
in the 21st century, such as the 2005, 2010 and 2015-16 droughts. Recent studies have
shown that in extreme drought years there is a significant increase in forest fires. Burning
increases the concentration of carbon monoxide (CO), atmospheric methane (CH4) and
particulate matter in the Amazonian atmosphere, generating smoke that covers large areas
and plays a vital role in environmental systems, air quality and strong adverse impacts.
about human health. Thus, at the regional scale, the present study investigated the impact
of biomass burning in the Amazon region on the spatiotemporal variability of methane
and carbon monoxide, particularly during drought years. In addition, at the local scale,
the impact on air quality of the urban area of Manaus was evaluated, focusing on the
levoglucosan, a biomass burning tracer, present in the PM2.5 during a period of El Niño
(2015) and a period of non-El Niño (2016), as well as, seasonal variability and its possible
regions of origin were analyzed during an intensive field experiment of surface PM2.5
sampling, from August 2017 to July 2018. Initially, from CH4, CO and fires satellite data,
an analysis of their interrelationships and spatiotemporal variability over the Amazon in
the period 2003-2012, focusing on the dry years of 2005, 2007 and 2010, was carried out.
Positive peaks were observed in the relationship between the increase in the number of
fires, mainly in the southern area of the Amazon, with consequent contributions to the
interannual variability of CO and CH4 during the dry years of 2005, 2007 and 2010 and
negative during the wet years. Afterwards, we analyzed the spatiotemporal variability of
the biomass burning and carbon monoxide during the 2005, 2010 and 2015 drought
episodes, in particular over the Amazon. During the dry season, the occurrences of fires
were lower in 2015 than in 2005 (-44%) and 2010 (-47%). On the other hand, in the dryto-wet transition season, they were higher in 2015 than in 2005 (+ 192%) and 2010 (+
332%). The CO concentration showed positive variations (up to + 30%) that occurred in
southern Amazonia and central Brazil during the dry seasons of 2005 and 2010, and north
of 20 ºS during the dry-to-wet transition season of 2015-16. In 2015 the fires occurred
mainly in the central and northern of the Amazon. Also, from the investigation of the
influence of biomass burning emissions on urban pollution in the metropolitan region of
Manaus during a strong El Niño (2015) and a non-El Niño (2016) period, it was observed
that CO concentration was up to 15% higher and levoglucosan concentration up to 500%
higher in Manaus metropolitan region during El Niño compared to non-El Niño period.
Finally, a well-defined seasonal cycle of levoglucosan was observed in the urban area of Manaus, from August 2017 to July 2018. From these surface measurements combined
with the biomass burning satellite data in the Amazon region and combining an ensemble
of stochastic back trajectories at the Manaus receptor within the Stochastic Time-Inverted
Lagrangian Transport (STILT) model, it was observed that the biomass burning in the
cities located east of Manaus, together with the contributions of the biomass burning
emissions from the eastern and southeastern regions of Pará State, were identified as the
main regions of origin of the biomass burning particles transported at the surface level in
the urban area of Manaus. Therefore, these results point to a strong degradation of air
quality that may occur in the metropolitan region of Manaus if drought and biomass
burning trends continue in the future.Na região amazônica, secas severas associadas às mudanças climáticas ocorreram
com maior frequência no século 21, como as secas de 2005, 2010 e 2015-16. Estudos
recentes mostraram que, nos anos de seca extremos, há um aumento significativo dos
incêndios florestais. As queimadas aumentam a concentração do monóxido de carbono
(CO), do metano atmosférico (CH4) e do material particulado na atmosfera da Amazônia,
gerando uma fumaça que cobre grandes áreas e desempenha papel vital nos sistemas
ambientais, na qualidade do ar e impactos adversos sobre a saúde humana. Assim, na
escala regional, o presente estudo investigou o impacto das queimadas da região
amazônica na variabilidade espaço-temporal do metano e do monóxido de carbono, em
particular, durante anos de seca intensa. Além disso, na escala local, avaliou-se o impacto
sobre a qualidade do ar da área urbana de Manaus com foco no traçador de queimada
levoglucosano presente no material particulado fino (MP2,5) durante um período de El
Niño (2015) e um período de não-El Niño (2016), bem como, analisou-se a variabilidade
sazonal e suas possíveis regiões de origem durante um experimento de campo intensivo
de amostragem de MP2,5 em superfície, entre agosto de 2017 e julho de 2018.
Inicialmente, a partir dos dados de satélite de CH4, CO e queimadas, foi realizada uma
análise das suas inter-relações e variabilidade espaço-temporal sobre a Amazônia no
período de 2003 a 2012, com foco nos anos secos de 2005, 2007 e 2010. Os resultados
mostraram ciclos sazonais consistentes das queimadas e CO com maiores valores durante
a estação seca. Observaram-se relações positivas entre o aumento do número de
queimadas, principalmente na porção sul da Amazônia, com consequentes contribuições
para a variabilidade interanual de CO e CH4, durante os anos secos de 2005, 2007 e 2010
e negativos durante os anos úmidos de 2008, 2009 e 2011. Posteriormente, analisou-se a
variabilidade espaço-temporal dos focos de queimadas e monóxido de carbono durante
os episódios de seca de 2005, 2010 e 2015, em particular sobre a Amazônia. As
ocorrências de queimadas na estação seca foram menores em 2015 do que em 2005 (-
44%) e 2010 (-47%). Por outro lado, na estação de transição seca-chuvosa, ocorreu um
maior número de queimadas em 2015 do que em 2005 (+192%) e 2010 (+332%). A
concentração de CO mostrou variações positivas (até +30%) ocorridas no sul da
Amazônia e no Brasil central durante as estações secas de 2005 e 2010, e ao norte de 20
ºS durante a estação de transição seca-chuvosa de 2015/2016. Em 2015 as queimadas
ocorreram, principalmente, na porção central e norte da Amazônia, uma área
historicamente com pouca ocorrência de queimadas. Ainda, a partir da investigação da influência das emissões de queima de biomassa da Amazônia sobre a poluição urbana na
região metropolitana de Manaus durante um forte período El Niño (2015) e um período
não-El Niño (2016), observou-se que a concentração de CO foi até 15% maior e a
concentração de levoglucosano foi até 500% maior na região metropolitana de Manaus
durante o El Niño, em comparação com o período não-El Niño. Por fim, observou-se um
ciclo sazonal bem definido do principal traçador de queima de biomassa (levoglucosano)
em superfície na área urbana de Manaus, entre agosto de 2017 a julho de 2018. A partir
dessas medidas em superfície, combinadas com os dados de queimadas na região
amazônica a partir de dados de satélite e simulações no modelo Stochastic Time-Inverted
Lagrangian Transport (STILT) para acompanhar a evolução do tempo de retorno de um
conjunto de partículas a partir de Manaus, observaram-se que as queimadas nas cidades
localizadas a leste de Manaus, juntamente com as contribuições das emissões das
queimadas das regiões leste e sudeste do Estado do Pará, foram identificadas como as
principais regiões de origem de partículas de queima de biomassa transportadas no nível
superficial na zona urbana de Manaus. Portanto, estes resultados apontam para uma
intensa degradação da qualidade do ar, que pode ocorrer na região metropolitana de
Manaus, se as tendências de seca e queima de biomassa continuarem no futuro
Maruina Müller, 1895 (Diptera: Psychodidae): Description of four new species from Brazil, with revised diagnoses for the genus and subgenera
No full textMaruina is an aquatic genus of Psychodidae with larvae and pupae adapted for life in flowing water. The genus is restricted to the Western Hemisphere, with the majority of species distributed in the Neotropical region. 39 Maruina species are described, with 11 currently known to occur in Brazil, all recorded from the eastern Biomes of Atlantic forest and Caatinga. Here we describe four new Maruina species collected from Brazil: Maruina (Aculcina) roraimensis sp. nov., Maruina (Maruina) kallyntrona sp. nov. and M. (M.) mystax sp. nov. constitute the first report of Maruina from Amazonia and M. (A.) pila sp. nov. from the southern portion of the Atlantic forest expands the distribution of the genus to Rio Grande do Sul, the southernmost state of Brazil. Type specimens of some described species were also studied. Redescriptions are completed for M. (M.) garota and M. (M.) namorada, and additional characters and figures are presented for M. (A.) duckhousei, M. (M.) barrettoi and M. (M.) jezeki. M. pilosella and M. spinosa are considered nomina dubia. Diagnostic characters for the genus and both subgenera are revised and distribution maps for Maruina species recorded in Brazil are provided. Copyright © 2019 Magnolia Press
Bioacessibilidade de saponinas presentes em tubérculos com potencial aplicação no controle de obesidade e colesterolIn Vitro dos macro e micronutrientes de plantas alimentícias não convencionais (PANC) in natura e processadas termicamente
No full textThe effects of stocking density on the hematology, plasma protein profile and immunoglobulin production of juvenile tambaqui (Colossoma macropomum) farmed in Brazil
No full textFarming of Amazonian native fish species holds great promise. One species whose characteristics make it suitable for intensive farming is tambaqui (Colossoma macropomum). However, there is a lack of consensus about the most suitable stocking density (SD) for intensive farming. More information on the physiology of fish in farming systems is thus required, as this would increase our understanding of the effects of stress on these fish. The aim of this study was therefore to evaluate the effect of different SDs on the hematology and plasma protein profile of tambaqui. To this end, juvenile tambaqui were exposed to the following different SDs (kg/m3) for 96 h: SD1 = 2.11; SD2 = 8.31; SD3 = 16.34; and SD4 = 27.40. Water quality was monitored, and blood was collected for hematological analysis and electrophoresis (SDS-PAGE) to analyze plasma protein and immunoglobulin profiles. Gill filaments were removed and the number of parasites (monogenoids) was counted. Multivariate PCA analysis revealed a strong positive association between the highest SDs (SD3 and SD4) and parasite count, immune cells (eosinophils, thrombocytes, monocytes and lymphocytes) and water ammonia and nitrite levels. Conversely, the highest SDs were negatively associated with water quality variables (pH, turbidity, conductivity and O2 content) and blood hematocrit. The results show that the highest SDs contributed to a deterioration in water quality, leading to increased MetHb levels, gill parasitism, an increase in the number of defense cells, altered protein profile and stimulation of immunoglobulin production. These changes suggest that the welfare of tambaqui is adversely affected by high SDs and increase our understanding of the effects of crowding stress on the physiology of the species. © 201
Occurrence of Amblycerus species in Cordia trichotoma seeds and their influence on germination
No full textForest species can have their seeds damaged by granivorous insects, especially by those in their larval stage. In this context, this study aims to report the occurrence of Amblycerus species in Cordia trichotoma seeds, to describe their main damage to seeds and effects on germination, as well as their associated hymenopteran parasitoids. Therefore, seven trees were selected in the municipality of Taquaruçu do Sul, RS, Brazil. Fruits were collected weekly from the medium third of the tree crown, from the beginning of their formation until total dehiscence. To examine the damage caused by granivorous insects within the fruits, 15 fruits from each tree were sectioned with a scalpel. Furthermore, 10 fruits from each tree were stored individually in clear plates to verify the occurrence and identification of granivorous insect species. Evidence of the damage caused to seeds was verified through the germination test by comparing preserved and damaged seeds, with four repetitions of 25 seeds each. The species Amblycerus longesuturalis and Amblycerus profaupar (Chrysomelidae: Bruchinae) were found associated with fruits of C. trichotoma. Female insects predominantly laid eggs on the superior part between the marcescent calyx and the fruit, and larvae perforated the fruit tegument to start consuming seed embryos and reserves. Bruquine larvae are parasitized by Hymenoptera of Bracon, Mirax, Omeganastatus and Triapsis genera. In conclusion, the germination of C. trichotoma seeds is significantly affected by emergence orifices caused by granivorous species. © 2019 Sociedade Brasileira de Entomologi
Five new species of Macrostomus Wiedemann and a checklist of Empididae (s. Str.) (Diptera) from Bolivia
No full textTen Bolivian species of Macrostomus Wiedemann were studied. Five species are redescribed based on type specimens described by Bezzi. The species are included in the following species-groups: four in the M. ferrugineus species-group: M. arcucinctus (Bezzi), M. argyrotarsis (Bezzi), M. dolichopterus (Bezzi) and M. grallatrix (Bezzi); three in the M. limbipennis species-group: M. macerrimus (Bezzi), M. montanus sp. nov. and M. rodriguezi sp. nov.; one species in the M. amazonensis species-group: M. falcatus sp. nov.; and two unplaced to species-group: M. trifidus sp. nov. and M. trilineatus sp. nov. A key to the 12 species of Macrostomus found in Bolivia, including M. limbipennis (Bezzi) and M. pictipennis (Bezzi), is presented. Macrostomus argyrotarsis (Bezzi) is also recorded for the first time from Peru. A checklist of 31 described species of Bolivian Empididae s. str. is included. Three empidid species originally described from Mexico that had previously been recorded from Bolivia, are excluded from the Bolivian fauna. Copyright © 2019 Magnolia Press
Single nucleotide polymorphisms of the genes IL-2, IL-2RB, and JAK3 in patients with cutaneous leishmaniasis caused by Leishmania (V.) guyanensis in Manaus, Amazonas, Brazil
Get PDFLeishmaniasis is a disease caused by intracellular protozoan parasites of the genus Leishmania. In endemic areas, only a portion of exposed subjects develops cutaneous leishmaniasis (CL), suggesting that the genetic inheritance of the host plays a vital role in both resistance and susceptibility to the disease. Interleukin-2 (IL-2) is a cytokine that plays a central role in the regulation of the immune response in infection through the axis IL-2/IL-2R (receptor) complex, triggering a series of intracellular events, among which the signaling of Janus kinase/signal transducers and activators of transcription (JAK-STAT). The present study aimed at verifying the possible relationship between single nucleotide polymorphism (s) (SNP s) in the genes IL-2, IL-2RB, and JAK3 in subjects with CL caused by Leishmania guyanensis in the city of Manaus, state of Amazonas, Brazil. 820 patients with CL and 850 healthy subjects (control group) coming from the same endemic areas as the patients were examined. The SNPs -2425G/A (rs4833248) and -330 T/G (rs2069762), located in the IL-2 gene promoter region, seem to influence the expression of the gene and the SNP +10558G/A (rs1003694) and +13295T/C (rs3212760) located in the 3rd intron of the IL-2RB gene and the 13th intron of the JAK3 gene, respectively, were studied by PCR-RFLP. Genotypes and alleles frequencies were obtained by direct counting. For the comparison between the two groups, the χ2 test with OR (odds ratio) and the 95% confidence interval (CI) were used. Similar genotypes and alleles frequencies for the different SNPs were observed in both patients with CL and healthy controls. Comparison of genotypic and allelic frequency between patients with CL and healthy subjects did not show any difference. These polymorphisms do not predict susceptibility to, or protection against the development of CL caused by L. guyanensis in the Amazonas. © 2019 de Araújo Santos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
