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1.
Braz. j. biol ; 79(2): 311-320, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989459

RESUMO

Abstract The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18'S - 1°19'S; 44°51'W - 44°53'W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I (˂ 29 cm), II (29.1 to 37.0) and III (≥ 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.


Resumo Atividade alimentar do pampo Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) em estuários na costa ocidental do Maranhão, Brasil. O presente trabalho descreve a atividade alimentar do Trachinotus cayennensis , coletado na Baía de Lençóis (1°18'S - 1°19'S; 44°51'W - 44°53'W) na costa oeste do Maranhão. Amostragens foram realizadas entre junho de 2012 e junho de 2013, utilizando redes de emalhar à deriva com tamanho de malha de 95 a 100 mm. Foram analisados ​​205 indivíduos (114 fêmeas e 91 machos). Encontraram-se diferenças estatisticamente significativas na proporção sexual nos meses de junho, setembro e dezembro de 2012. Os itens alimentares foram analisados ​​com base na frequência de ocorrência e utilizando o método volumétrico, com o subsequente cálculo do índice de importância alimentar. Três grupos de tamanho foram definidos para determinar possíveis mudanças ontogenéticas nos hábitos alimentares com base na faixa de tamanho dos indivíduos coletados: I (˂ 29 cm), II (29,1 a 37,0) e III (≥ 37,1). Foram identificadas 11 categorias de alimentos: moluscos, poliquetas, crustáceos, nematoides, insetos, algas, briozoários, ophiuro, peixes, matéria vegetal e sedimentos. A variedade de itens na dieta de T. cayennensis indica uma plasticidade alimentar considerável e um comportamento oportunista. As variações sazonais influenciaram o padrão alimentar da espécie, com maior atividade de alimentação na estação seca. A considerável disponibilidade de recursos nos habitats estuarinos da costa oeste do Maranhão constitui outro fator que exerce influência sobre o comportamento alimentar desta espécie.


Assuntos
Animais , Masculino , Feminino , Perciformes/fisiologia , Comportamento Alimentar/fisiologia , Brasil , Estuários
2.
Infect Genet Evol ; 69: 255-266, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30763774

RESUMO

Worldwide rotaviruses A (RVA) are responsible for approximately 215,000 deaths annually among children aged <5 years. RVA G1P[8] remains associated with >50% of gastroenteritis cases in this age group. The aim of this study was to assess the genetic variability of G1P[8] strains detected in children with severe diarrhea in Belém, Pará, Brazil, during the post-rotavirus vaccine introduction era. Phylogenetic analysis clustered the VP4 and VP7 genes of 40 samples selected between 2009 and 2011 into lineages found to be different from the Rotarix® vaccine strain. A detailed investigation of their complete genotype constellations identified 2 reassortant viruses (5%), resulting from reassortments between the genogroups Wa-like and DS-1-like (G1-P[8]-I1-R2-C1-M1-A1-N1-T2-E1-H1) and Wa-like and AU-1-like (G1-P[8]-I1-R3-C1-M1-A1-N1-T1-E1-H1) genotype constellations. A comparison of the amino acid residues presents in the antigenic epitopes of VP7 and VP4, showed differences in the electrostatic charges distribution, between wild type Brazilian strains and the Rotarix® and RotaTeq® vaccine strains. These findings reflect the structural analyses of the antigenic regions of VP7 and VP4 of the RVA G1P[8] in children with gastroenteritis in Northern Brazil raising the hypothesis that structural modifications at these sites over time may account for the emergence of new strains that could possibly pose a challenge to current vaccines.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/imunologia , Brasil/epidemiologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Diarreia/prevenção & controle , Variação Genética , Genoma Viral , Humanos , Filogenia , Vírus Reordenados/genética , Vírus Reordenados/imunologia , Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Análise de Sequência de DNA
3.
Braz J Biol ; 79(2): 311-320, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30133557

RESUMO

The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18'S - 1°19'S; 44°51'W - 44°53'W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I (˂ 29 cm), II (29.1 to 37.0) and III (≥ 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.


Assuntos
Comportamento Alimentar/fisiologia , Perciformes/fisiologia , Animais , Brasil , Estuários , Feminino , Masculino
4.
Genet Mol Res ; 8(1): 215-22, 2009 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19283688

RESUMO

Marine turtles are increasingly being threatened worldwide by anthropogenic activities. Better understanding of their life cycle, behavior and population structure is imperative for the design of adequate conservation strategies. The mtDNA control region is a fast-evolving matrilineal marker that has been employed in the study of marine turtle populations. We developed and tested a simple molecular tracing system for Caretta caretta mtDNA haplotypes by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). Using this technique, we were able to distinguish the SSCP patterns of 18 individuals of the haplotypes CC-A4, CC-A24 and CCxLO, which are commonly found in turtles sampled on the Brazilian coast. When we analyzed 15 turtles with previously unknown sequences, we detected two other haplotypes, in addition to the other four. Based on DNA sequencing, they were identified as the CC-A17 and CC-A1 haplotypes. Further analyses were made with the sea turtles, Chelonia mydas (N = 8), Lepidochelys olivacea (N = 3) and Eretmochelys imbricata (N = 1), demonstrating that the PCR-SSCP technique is able to distinguish intra- and interspecific variation in the family Cheloniidae. We found that this technique can be useful for identifying sea turtle mtDNA haplotypes, reducing the need for sequencing.


Assuntos
DNA Mitocondrial/química , Polimorfismo Genético , Polimorfismo Conformacional de Fita Simples/genética , Tartarugas/genética , Animais , Geografia , Reação em Cadeia da Polimerase/métodos
5.
J Chem Phys ; 122(9): 094309, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15836130

RESUMO

In this work, we present a theoretical study on elastic electron collisions from three isoelectronic free radicals (CNN, NCN, and CCO) in the low incident energy range. More specifically, calculated differential, integral, and momentum transfer cross sections are reported in the 1-30 eV energy range. Calculations are performed in the static-exchange and static-exchange-polarization levels. The iterative Schwinger variational method is used to solve the scattering equations. Our study reveals that the calculated cross sections for the three targets are significantly different at incident energies below 10 eV. Above that energy, a remarkable similarity among the calculated results is seen.

6.
Braz J Biol ; 61(2): 217-38, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11514890

RESUMO

The feeding habits of Rioraja agassizii (syn. Raja agassizii) and Psammobatis extenta (syn. Psammobatis glansdissimilis) of the South-eastern Brazilian coast were studied by means of stomach content analysis. The samples were obtained on eight seasonal oceanographic cruises, carried out between October 1985 and July 1987. The importance of each food item was evaluated on the basis of the Index of Relative Importance and the feeding similarity by Percentage of Similarity. The results indicated that both species are benthic feeders, preying mainly on Crustacea, especially Amphipoda, Caridea and Brachyura. Teleostei were also important for R. agassizii. Seasonal variation of the diet seems to be associated with the availability of the prey, whose distribution and abundance are related to the dynamics of the water masses of the region. Juveniles and adults of P. extenta exploited the same resources while juveniles and adults of R. agassizii presented low diet similarity during most of the year. Caridea were an important food for all length classes of R. agassizii, while Amphipoda were for smaller specimens, and Teleostei for larger ones. The feeding overlap between the two species was higher during autumn 1986, winter 1986 and winter 1987.


Assuntos
Dieta , Comportamento Alimentar , Rajidae/fisiologia , Animais , Brasil , Feminino , Conteúdo Gastrointestinal , Masculino , Estações do Ano , Especificidade da Espécie
7.
Braz J Biol ; 61(2): 197-216, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11514889

RESUMO

Food habits and daily feeding activity of fish populations are important ecological variables for understanding their role in the ecosystem. Diel changes in feeding activity and dietary composition of juvenile whitemouth croaker Micropogonias furnieri, shortfin corvina Isopisthus parvipinnis, shorthead drum Larimus breviceps and of juvenile and adult banded croaker Paralonchurus brasiliensis were investigated from samples taken over a 24 hours period from 4 to 5 September 1987 on the continental shelf off South-eastern Brazil. Whitemouth croaker and banded croaker had a benthic diet based on polychaetes and some caridean shrimps and showed no diel feeding pattern. Shortfin corvina and shorthead drum fed on crustaceans and teleostean fish, the former species primarily on pelagic sergestid shrimps and benthic caridean shrimps, and the latter mainly on pelagic sergestid shrimps, mysidacean and benthic caridean shrimps. Shortfin corvina is primarily a diurnal feeder, but preyed on some items only at night. Shorthead drum is a night feeder, with minimum stomach fullness values between dawn and daytime, and maximum values between dusk and night time.


Assuntos
Ração Animal/análise , Comportamento Alimentar , Peixes/fisiologia , Animais , Comportamento Animal , Ecossistema , Preferências Alimentares/classificação , Estatísticas não Paramétricas
8.
Rev. bras. biol ; 61(2): 197-216, May 2001. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-298637

RESUMO

Food habits and daily feeding activity of fish populations are important ecological variables for understanding their role in the ecosystem. Diel changes in feeding activity and dietary composition of juvenile whitemouth croaker Micropogonias furnieri, shortfin corvina Isopisthus parvipinnis, shorthead drum Larimus breviceps and of juvenile and adult banded croaker Paralonchurus brasiliensis were investigated from samples taken over a 24 hours period from 4 to 5 September 1987 on the continental shelf off South-eastern Brazil. Whitemouth croaker and banded croaker had a benthic diet based on polychaetes and some caridean shrimps and showed no diel feeding pattern. Shortfin corvina and shorthead drum fed on crustaceans and teleostean fish, the former species primarily on pelagic sergestid shrimps and benthic caridean shrimps, and the latter mainly on pelagic sergestid shrimps, mysidacean and benthic caridean shrimps. Shortfin corvina is primarily a diurnal feeder, but preyed on some items only at night. Shorthead drum is a night feeder, with minimum stomach fullness values between dawn and daytime, and maximum values between dusk and night time


Assuntos
Animais , Ração Animal/análise , Comportamento Alimentar , Peixes/fisiologia , Comportamento Animal , Ecossistema , Preferências Alimentares , Estatísticas não Paramétricas
9.
Rev. bras. biol ; 61(2): 217-238, May 2001. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-298638

RESUMO

The feeding habits of Rioraja agassizii (syn. Raja agassizii) and Psammobatis extenta (syn. Psammobatis glansdissimilis) of the South-eastern Brazilian coast were studied by means of stomach content analysis. The samples were obtained on eight seasonal oceanographic cruises, carried out between October 1985 and July 1987. The importance of each food item was evaluated on the basis of the Index of Relative Importance and the feeding similarity by Percentage of Similarity. The results indicated that both species are benthic feeders, preying mainly on Crustacea, especially Amphipoda, Caridea and Brachyura. Teleostei were also important for R. agassizii. Seasonal variation of the diet seems to be associated with the availability of the prey, whose distribution and abundance are related to the dynamics of the water masses of the region. Juveniles and adults of P. extenta exploited the same resources while juveniles and adults of R. agassizii presented low diet similarity during most of the year. Caridea were an important food for all length classes of R. agassizii, while Amphipoda were for smaller specimens, and Teleostei for larger ones. The feeding overlap between the two species was higher during autumn 1986, winter 1986 and winter 1987


Assuntos
Animais , Masculino , Feminino , Ração Animal/análise , Rajidae/fisiologia , Brasil , Conteúdo Gastrointestinal , Escalas de Valor Relativo , Estações do Ano
10.
Cad Saude Publica ; 16(2): 343-50, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10883033

RESUMO

We investigated the impact of multidrug therapy (MDT) on the epidemiological pattern of leprosy in Juiz de Fora, Brazil, from 1978 to 1995. Evaluation of 1,283 medical charts was performed according to the treatment regimen used in two different periods. Following the introduction of MDT in 1987, prevalence of leprosy decreased from 22 patients/10,000 inhabitants to 5.2 patients/10,000 inhabitants in 1995. Incidence rate of leprosy was lower in period II (1987-1995) than in period I (1978-1986). Decreasing prevalence and incidence appear to be related to drug efficacy rather than decreased case identification, since both self-referred and professionally referred treatment increased markedly from period I to period II. For both periods, multibacillary leprosy was the most frequent clinical form of the disease (+/-68%), and the main infection risk factor identified was household contact. Leprosy is predominantly manifested in adults, but an increase in the number of very old and very young patients was observed in period II. The MDT program has been effective both in combating leprosy and in promoting awareness of the disease.


Assuntos
Hanseníase/tratamento farmacológico , Hanseníase/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , Quimioterapia Combinada , Humanos , Incidência , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Prevalência
11.
J Ethnopharmacol ; 57(2): 131-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9254115

RESUMO

After interviewing natives and migrants from the Amazon region of Brazil about plants traditionally used for treatment of malaria fever and/or liver disorders, we selected and identified 41 different species, including the native Bidens (Asteraceae). We have undertaken an antimalarial study of Bidens pilosa and other species of Bidens from abroad. The crude ethanol extracts (whole plant, leaves and roots) and the chloroform and butanol fractions from B. pilosa at concentrations of 50 microg/ml caused up to 90% inhibition of Plasmodium falciparum growth in vitro. In vivo the fractions caused partial reduction of Plasmodium berghei parasitemia in mice. The ethanol extracts from nine different Bidens species collected outside Brazil were tested, and seven inhibited parasite growth in vitro by 65-91%. As B. pilosa appears to be a promising antimalarial agent, we further characterized the substances responsible for such activity. HPLC analysis using a photo diode-array detector showed phenyl acetylene and flavonoids in the ethanol extract from the leaves and roots. The chloroform fractions from the roots, which caused 86% inhibition of parasite growth in vitro, contained a major component identified as 1-phenyl-1,3-diyn-5-en-7-ol-acetate. The association of antimalarial activity and the presence of acetylene compounds is discussed. In summary, all species of Bidens which had aliphatic acetylenes (6-14 each) were also very active, whereas extracts of B. parriflora and of B. bitternata with none or the three acetylenes, respectively as reported in literature, were inactive or had a borderline activity in vitro.


Assuntos
Acetileno/química , Antimaláricos/farmacologia , Flavonoides/química , Malária/tratamento farmacológico , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Acetileno/isolamento & purificação , Animais , Antimaláricos/isolamento & purificação , Antimaláricos/uso terapêutico , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Flavonoides/isolamento & purificação , Humanos , Camundongos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Especificidade da Espécie
12.
Clin Immunol Immunopathol ; 83(3): 254-63, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9175914

RESUMO

NF-kappaB is a regulatory protein of immune response genes and a candidate for targeting in immunosuppressive therapy. NF-kappaB proteins are formed from components of which p50 (NFkappaB1) is a subunit. By targeting p50 gene expression with specific antisense 3' phosphorothioate-oligodeoxynucleotides (3' PS-ODNs), an effect upon NF-kappaB regulation and immunoglobulin synthesis in murine B cells was achieved. A 49% decrease in p50 protein was induced by treatment of WEHI 231 B cells with p50 antisense 3' PS-ODNs and not by control 3' PS-ODNs. p50 antisense specifically reduced the expression of NF-kappaB by 51%, but not the transcription factor, Oct-1. In the BXSB murine model of autoimmunity, p50 antisense inhibited NF-kappaB expression and total IgM and IgG synthesis, but, more importantly, dsDNA antibodies were reduced 90%. These results validate the use of p50 antisense to reduce NF-kappaB expression and, by downregulating the immune response, has application in the treatment of autoimmune disorders.


Assuntos
Linfócitos B/metabolismo , Imunoglobulinas/biossíntese , NF-kappa B/antagonistas & inibidores , NF-kappa B/biossíntese , Oligonucleotídeos Antissenso/farmacologia , Tionucleotídeos/farmacologia , Animais , Anticorpos Antinucleares/biossíntese , Autoanticorpos/análise , Doenças Autoimunes/diagnóstico , Autoimunidade/fisiologia , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , DNA/imunologia , Modelos Animais de Doenças , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Subunidade p50 de NF-kappa B , Baço/citologia , Células Tumorais Cultivadas
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