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1.
Environ Pollut ; 265(Pt B): 114817, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32570021

RESUMO

This study reports for the first time the ingestion of meso- (5.01-25 mm) and microplastics (1 µm-5 mm) by the sea anemone Bunodosoma cangicum, the most abundant actiniarian species on the Amazon coast. At three sites on the coast of Pará, Brazil, anemones were collected from beachrocks in the intertidal zone (30 at each site), measured (pedal disc diameter, mm) and weighed (wet weight, g). The contents of the gastrovascular cavity were extracted and analyzed under a stereoscope. The recovered plastic particles were characterized by Fourier Transform Infrared (FTIR) spectroscopy. Overall, 139 microplastic and 2 mesoplastic items were identified in 68 individuals (75.6%) among the 90 examined, with a mean of 1.6 (±1.5) items per individual. Plastic fibers comprised about 84% of the ingested plastics, followed by fragments (∼12%) and films (∼4%). Particle diameters ranged from 0.10 to 9.17 mm (1.57 ± 1.23 mm). A weak positive correlation was found between the weight of anemones and the number of plastic particles in the gastrovascular cavity (p = 0.03) and between the number of prey items and the number of plastic particles in the gastrovascular cavity (p < 0.01). The main polymers identified by FTIR analysis were polyethylene terephthalate (PET), polypropylene (PP), polyamide (PA), polyurethane (PU), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polystyrene (PS) and rayon. Sea anemones ingested significantly more plastic debris at the most urbanized and populous sampling sites. This study provides the first evidence of microplastics contamination of marine invertebrates from the Amazon coast. Abundant species such as B. cangicum have the potential to monitor the levels of plastic contamination in the region. Our results support this potential, as the species showed a high frequency of plastic ingestion and allowed detection of plastic contamination even in the best-preserved area where anemones were collected.


Assuntos
Anêmonas-do-Mar , Poluentes Químicos da Água/análise , Animais , Brasil , Monitoramento Ambiental , Microplásticos , Plásticos
2.
Braz. j. biol ; 76(2): 511-519, Apr.-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-781405

RESUMO

Abstract Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a “quilombola” community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.


Resumo O conhecimento local acerca da biodiversidade vem sendo utilizado em pesquisas voltadas ao uso e manejo de recursos naturais aliados à conservação. Entre estes recursos, destaca-se o Pequi (Caryocar brasiliense Cambess.) devido à sua importância econômica e alimentar para comunidades que vivem no Cerrado. No quilombo de Pontinha, localizado na região central do estado de Minas Gerais, um estudo etnoecológico sobre o Pequi foi desenvolvido, a fim de subsidiar iniciativas de geração de trabalho e renda para esta comunidade. Informações foram obtidas por meio de entrevistas semiestruturadas, observação participante e travessia. Alimentação familiar (97%), produção de sabão (67%), produção de óleo (37%), tratamento medicinal (17%) e comércio (3%) foram os principais usos do Pequi citados pelos comunitários. Abelhas foram os visitantes florais com maior Índice de Saliência (S=0,639). Dentre os frugívoros que se alimentam de frutos não caídos, as aves apresentaram maior Saliência (S=0,359) e os insetos foram os mais importantes frugívoros entre os que utilizam frutos caídos (S=0,574). Brocas, lagartas folívoras e que atacam troncos e raízes foram as pragas mais citadas. Os indivíduos jovens de Pequi são, segundo os entrevistados, os mais afetados pelo fogo devido ao menor porte e por ter a casca menos espessa. O reconhecimento da importância cultural e ecológica do Pequi tem mobilizado a comunidade, que demonstra interesse em fazer dessa espécie uma alternativa de renda.


Assuntos
Humanos , Animais , Abelhas/fisiologia , Aves/fisiologia , Ericales , Frutas , Brasil/etnologia , Etnobotânica , Biodiversidade , Grupos Populacionais , Meio Ambiente , Fenômenos Ecológicos e Ambientais , Herbivoria , Preferências Alimentares
3.
Braz J Biol ; 76(2): 511-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27058602

RESUMO

Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a "quilombola" community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.


Assuntos
Abelhas/fisiologia , Aves/fisiologia , Ericales , Frutas , Animais , Biodiversidade , Brasil/etnologia , Fenômenos Ecológicos e Ambientais , Meio Ambiente , Etnobotânica , Preferências Alimentares , Herbivoria , Humanos , Grupos Populacionais
4.
Braz J Med Biol Res ; 44(4): 345-53, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21484063

RESUMO

In vivo proton magnetic resonance spectroscopy (¹H-MRS) is a technique capable of assessing biochemical content and pathways in normal and pathological tissue. In the brain, ¹H-MRS complements the information given by magnetic resonance images. The main goal of the present study was to assess the accuracy of ¹H-MRS for the classification of brain tumors in a pilot study comparing results obtained by manual and semi-automatic quantification of metabolites. In vivo single-voxel ¹H-MRS was performed in 24 control subjects and 26 patients with brain neoplasms that included meningiomas, high-grade neuroglial tumors and pilocytic astrocytomas. Seven metabolite groups (lactate, lipids, N-acetyl-aspartate, glutamate and glutamine group, total creatine, total choline, myo-inositol) were evaluated in all spectra by two methods: a manual one consisting of integration of manually defined peak areas, and the advanced method for accurate, robust and efficient spectral fitting (AMARES), a semi-automatic quantification method implemented in the jMRUI software. Statistical methods included discriminant analysis and the leave-one-out cross-validation method. Both manual and semi-automatic analyses detected differences in metabolite content between tumor groups and controls (P < 0.005). The classification accuracy obtained with the manual method was 75% for high-grade neuroglial tumors, 55% for meningiomas and 56% for pilocytic astrocytomas, while for the semi-automatic method it was 78, 70, and 98%, respectively. Both methods classified all control subjects correctly. The study demonstrated that ¹H-MRS accurately differentiated normal from tumoral brain tissue and confirmed the superiority of the semi-automatic quantification method.


Assuntos
Neoplasias Encefálicas/classificação , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Humanos , Espectroscopia de Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Sensibilidade e Especificidade , Adulto Jovem
5.
Braz. j. med. biol. res ; 44(4): 345-353, Apr. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-581486

RESUMO

In vivo proton magnetic resonance spectroscopy (¹H-MRS) is a technique capable of assessing biochemical content and pathways in normal and pathological tissue. In the brain, ¹H-MRS complements the information given by magnetic resonance images. The main goal of the present study was to assess the accuracy of ¹H-MRS for the classification of brain tumors in a pilot study comparing results obtained by manual and semi-automatic quantification of metabolites. In vivo single-voxel ¹H-MRS was performed in 24 control subjects and 26 patients with brain neoplasms that included meningiomas, high-grade neuroglial tumors and pilocytic astrocytomas. Seven metabolite groups (lactate, lipids, N-acetyl-aspartate, glutamate and glutamine group, total creatine, total choline, myo-inositol) were evaluated in all spectra by two methods: a manual one consisting of integration of manually defined peak areas, and the advanced method for accurate, robust and efficient spectral fitting (AMARES), a semi-automatic quantification method implemented in the jMRUI software. Statistical methods included discriminant analysis and the leave-one-out cross-validation method. Both manual and semi-automatic analyses detected differences in metabolite content between tumor groups and controls (P < 0.005). The classification accuracy obtained with the manual method was 75 percent for high-grade neuroglial tumors, 55 percent for meningiomas and 56 percent for pilocytic astrocytomas, while for the semi-automatic method it was 78, 70, and 98 percent, respectively. Both methods classified all control subjects correctly. The study demonstrated that ¹H-MRS accurately differentiated normal from tumoral brain tissue and confirmed the superiority of the semi-automatic quantification method.


Assuntos
Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Espectroscopia de Ressonância Magnética/métodos , Estadiamento de Neoplasias , Projetos Piloto , Sensibilidade e Especificidade
6.
Eur J Clin Microbiol Infect Dis ; 28(10): 1167-76, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19468763

RESUMO

The replication of hepatitis A virus (HAV) is via a complementary negative-strand RNA. Each negative strand may serve as a template for the synthesis of many positive strands. The aim of this study was to detect the intermediate replicative (negative strand) of HAV in order to monitor its replication in vitro and in vivo. Real-time polymerase chain reaction (PCR) was standardized to detect the intermediate replicative of HAV in cell culture and liver from non-human primates infected experimentally. HAV primers from the 5' non-translated region and VP3 were used in the cDNA synthesis of negative-strand RNA. The negative strand was detected in the infected cell lines and liver by highly strand-specific rTth recombinant Thermus thermophilus DNA polymerase reverse transcription followed by quantitative PCR. The results indicate that the negative-strand HAV RNA can be detected in vivo and in vitro. This model is an approach for assessing the dynamic patterns of replication and should represent a valuable tool for the monitoring of HAV replications in cell cultures and for the evaluation of experimental infections in animal models.


Assuntos
DNA Complementar/biossíntese , Vírus da Hepatite A/fisiologia , Hepatite A/virologia , Reação em Cadeia da Polimerase/métodos , RNA Viral/genética , Replicação Viral/fisiologia , Regiões 5' não Traduzidas , Animais , Proteínas do Capsídeo , Células Cultivadas , Modelos Animais de Doenças , Amplificação de Genes , Vírus da Hepatite A Humana/fisiologia , Humanos , Cinética , Fígado/virologia , Fragmentos de Peptídeos , Reação em Cadeia da Polimerase/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
7.
Braz J Med Biol Res ; 39(7): 873-81, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16862277

RESUMO

The Northeast region is the location of most cases of acute hepatitis A virus (HAV) in Brazil. In the present study, the genotypes of HAV strains from Pernambuco State, one of most populous states in the Northeast region, were characterized. Blood samples positive for anti-HAV IgM from 145 individuals (mean age = 29.1 years), collected during 2002 and 2003, were submitted to nested RT-PCR for amplification of the 5'non-translated region (5'NTR) and VP1/2A regions of the HAV genome. The VP1/2A and 5'NTR regions were amplified in 39 and 21% of the samples, respectively. Nucleotide sequencing was carried out in 46% of VP1/2A and in 53% of 5'NTR isolates. The identity in nucleotide sequence of the VP1/2A region ranged from 93.6 to 100.0%. Phylogenetic analysis of the VP1/2A sequences showed that 65% belong to sub-genotype IA and 35% to sub-genotype IB. Co-circulation of both sub-genotypes was observed in the two years studied. Distinct clusters of highly related sequences were observed in both sub-genotypes, suggesting endemic circulation of HAV strains in this area. In the 5'NTR isolates, 92.7-99.2% identity was observed and two isolates presented one deletion at position 413. Phylogenetic analysis showed that genotype IA strains cluster in the tree in the same way as genotype IB strains, but one IIIA isolate from Spain clusters with genotype IB strains. These results do not allow us to state that 5'NTR could be used to genotype HAV sequences. This is the first report of co-circulation of sub-genotypes IA and IB in this region, providing additional information about the molecular epidemiology of HAV strains in Brazil.


Assuntos
Regiões 5' não Traduzidas/genética , Vírus da Hepatite A/genética , Hepatite A/virologia , RNA Viral/análise , Proteínas Estruturais Virais/genética , Adulto , Sequência de Bases , Brasil , Feminino , Genoma Viral , Genótipo , Vírus da Hepatite A/classificação , Vírus da Hepatite A/isolamento & purificação , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA
8.
Braz. j. med. biol. res ; 39(7): 873-881, July 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-431558

RESUMO

The Northeast region is the location of most cases of acute hepatitis A virus (HAV) in Brazil. In the present study, the genotypes of HAV strains from Pernambuco State, one of most populous states in the Northeast region, were characterized. Blood samples positive for anti-HAV IgM from 145 individuals (mean age = 29.1 years), collected during 2002 and 2003, were submitted to nested RT-PCR for amplification of the 5'non-translated region (5'NTR) and VP1/2A regions of the HAV genome. The VP1/2A and 5'NTR regions were amplified in 39 and 21 percent of the samples, respectively. Nucleotide sequencing was carried out in 46 percent of VP1/2A and in 53 percent of 5'NTR isolates. The identity in nucleotide sequence of the VP1/2A region ranged from 93.6 to 100.0 percent. Phylogenetic analysis of the VP1/2A sequences showed that 65 percent belong to sub-genotype IA and 35 percent to sub-genotype IB. Co-circulation of both sub-genotypes was observed in the two years studied. Distinct clusters of highly related sequences were observed in both sub-genotypes, suggesting endemic circulation of HAV strains in this area. In the 5'NTR isolates, 92.7-99.2 percent identity was observed and two isolates presented one deletion at position 413. Phylogenetic analysis showed that genotype IA strains cluster in the tree in the same way as genotype IB strains, but one IIIA isolate from Spain clusters with genotype IB strains. These results do not allow us to state that 5'NTR could be used to genotype HAV sequences. This is the first report of co-circulation of sub-genotypes IA and IB in this region, providing additional information about the molecular epidemiology of HAV strains in Brazil.


Assuntos
Humanos , Masculino , Feminino , Adulto , /genética , Vírus da Hepatite A/genética , Hepatite A/virologia , RNA Viral/análise , Proteínas Estruturais Virais/genética , Sequência de Bases , Brasil , Genoma Viral , Genótipo , Vírus da Hepatite A/classificação , Vírus da Hepatite A/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA
9.
J Clin Virol ; 29(4): 254-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15018853

RESUMO

BACKGROUND: Hepatitis A virus (HAV) infection is the leading cause of clinically apparent viral hepatitis in many parts of the world, including developed and developing countries. Only limited information is available regarding the seronegative viremic window that follows HAV infection, and no systematic search has been reported for HAV RNA positive, IgM anti-HAV negative serum samples during hepatitis A outbreaks. OBJECTIVES: To determine the proportion of HAV infected individuals among (i) children who were tested negative for anti-HAV antibodies during hepatitis A outbreaks which occurred in a public school (n = 157) and a child care center (n = 38); (ii) subjects (n = 46) initially classified as acute non-A-C hepatitis patients after clinical examination and serological tests (sporadic cases). STUDY DESIGN: Reverse transcription (RT)-PCR was performed to detect the presence of HAV genome in serum samples collected from anti-HAV negative, susceptible subjects. RESULTS: HAV RNA was detected in 19/157 (12%) and 5/38 (13%) anti-HAV negative children from the public school and child care center, respectively. Twelve (26%) out of the 46 acute hepatitis patients (sporadic cases) were also HAV RNA positive. From nine of these 12 patients, a second blood sample was obtained 18-34 days after the first one: all nine had seroconverted to IgM anti-HAV, and their serum transaminases had reached elevated levels (mean ALT, 418; mean AST, 241). CONCLUSIONS: Detection of HAV RNA before IgM anti-HAV seroconversion may be used as an early diagnosis method during hepatitis A outbreaks. HAV RNA testing should also help to elucidate acute hepatitis cases of unknown etiology.


Assuntos
Vírus da Hepatite A/isolamento & purificação , Hepatite A/diagnóstico , Hepatite A/virologia , RNA Viral/sangue , Adolescente , Adulto , Criança , Creches , Pré-Escolar , Surtos de Doenças , Feminino , Hepatite A/epidemiologia , Anticorpos Anti-Hepatite A/sangue , Vírus da Hepatite A/genética , Humanos , Imunoglobulina M/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Instituições Acadêmicas , Transaminases/sangue , Viremia
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