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1.
Braz J Biol ; 83: e271913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37194827

RESUMO

Rhodnius neglectus is a wild triatomine, vector of the protozoan Trypanosoma cruzi, which causes Chagas' disease, and feeds on the blood of small mammals, being essential for its growth and reproduction. Accessory glands of the female reproductive tract are important in insect reproduction, but their anatomy and histology in R. neglectus are poorly studied. The aim of this work was to describe the histology and histochemistry of the accessory gland of the female reproductive tract of R. neglectus. The reproductive tract of five females of R. neglectus was dissected and the accessory glands transferred to Zamboni's fixative solution, dehydrated in a crescent series of ethanol, embedded in historesin, sectioned at 2 µm thick, stained with toluidine blue for histological analysis or mercury bromophenol blue for detection of total proteins. The accessory gland R. neglectus is tubular, without branches, opening in the dorsal region of the vagina and differing along its length in proximal and distal regions. In the proximal region, the gland is lined by the cuticle with a layer of columnar cells associated with muscle fibers. In the distal region of the gland, the epithelium has spherical secretory cells with terminal apparatus and conducting canaliculi opening in the lumen through pores in the cuticle. Proteins were identified in the gland lumen, terminal apparatus, nucleus and cytoplasm of secretory cells. The histology of the R. neglectus gland is similar to that found in other species of this genus, but with variations in the shape and size of its distal region.


Assuntos
Doença de Chagas , Rhodnius , Trypanosoma cruzi , Animais , Feminino , Rhodnius/anatomia & histologia , Rhodnius/fisiologia , Insetos Vetores/anatomia & histologia , Insetos Vetores/fisiologia , Trypanosoma cruzi/fisiologia , Reprodução , Mamíferos
2.
Phys Chem Chem Phys ; 23(31): 16795-16805, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34323251

RESUMO

Organic/inorganic van der Waals heterojunctions formed by a combination of 2D materials with semiconductor polymer films enable the fabrication of new device architectures that are interesting for electronic and optoelectronic applications. Here, we investigated the charge-transfer dynamics at the interface between 2D layered franckeite (Fr) and two thiophene-based conjugated polymers (PFO-DBT and P3HT) from the resonantly core-excited electron. The unoccupied electronic states of PFO-DBT/Fr and P3HT/Fr heterojunctions were studied using near-edge X-ray absorption fine structure (NEXAFS) and resonant Auger (RAS) synchrotron-based spectroscopies. We found evidence of ultrafast (subfemtosecond charge-transfer times) interfacial electron delocalization pathways from specific electronic states. For the interface between the PFO-DBT polymer and exfoliated franckeite, the most efficient interfacial electron delocalization pathways were found through π*(S-N) and π*(S-C) electronic states corresponding to the benzothiadiazole and thiophene units. On the other hand, for the P3HT polymer, we found that electrons excited to π-π* and S1s-π*(C-C) electronic states of the P3HT polymer are the most affected by the presence of exfoliated franckeite and consequently are the main interfacial electron-transfer pathways in this heterojunction. Our results have important implications in understanding how ultrafast electron delocalization is taking place in organic/inorganic van der Waals heterojunctions, which is relevant information in designing new devices involving these systems.

3.
Braz. j. biol ; 79(1): 144-148, Jan.-Mar 2019. graf
Artigo em Inglês | LILACS | ID: biblio-984000

RESUMO

Abstract Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) is a potential vector of Chagas's disease and the comprehension of its reproductive biology is an important tool to control this insect. In the reproductive tract of female insects, the spermatheca plays a crucial role storing male spermatozoa after mating. Whithin insects the spermatheca shows a wide morphological diversity and the analysis of this characteristic can contribute to understand the reproductive biology of the species. This study describes the histology and histochemistry of the spermatheca of T. lecticularia. Females have a pair of elongated spermathecal reservoirs without associated accessory gland. The reservoir opens into the common oviduct via a narrow muscular duct. The reservoir epithelium has single layer of columnar secretory cells. The control of the release of spermatozoa from the spermatheca occurs via the muscular duct. The anatomical features of the spermatheca of T. lecticularia resemble those described of other Reduviidae. However, the histological and histochemical features of spermatheca observed in T. lecticularia were important to explain the maintenance of the viability of the spermatozoa stored.


Resumo Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) é um potencial vetor da doença de Chagas e a compreensão de sua biologia reprodutiva é um importante fator para seu controle populacional. No aparelho reprodutor feminino dos insetos, a espermateca desempenha a importante funcão de armazenar os espermatozoides após cópula. Nos insetos, a espermateca apresenta uma ampla diversidade morfológica e a análise destas características pode contribuir com o entendimento da biologia reprodutiva das espécies. Este estudo descreve histológica e histoquimicamente a espermateca de T. lecticularia. As fêmeas tem um par de espermatecas alongadas sem glândulas acessórias associadas. O reservatório conecta-se ao oviduto comum através de um ducto muscular curto que controla a liberação dos espermatozoides. O epitélio do reservatório possui uma camada de células secretoras colunares. As características anatômicas da espermateca de T. lecticularia são semelhantes às encontradas em outros Reduviidae. Entretanto, as características histológicas e histoquímicas observadas na espermateca são importantes para explicar a manutenção da viabilidade dos espermatozoides armazenados.


Assuntos
Animais , Masculino , Feminino , Triatoma/fisiologia , Reprodução , Espermatozoides/citologia , Espermatozoides/fisiologia , Triatoma/citologia
4.
Braz J Biol ; 79(1): 144-148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29590252

RESUMO

Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) is a potential vector of Chagas's disease and the comprehension of its reproductive biology is an important tool to control this insect. In the reproductive tract of female insects, the spermatheca plays a crucial role storing male spermatozoa after mating. Whithin insects the spermatheca shows a wide morphological diversity and the analysis of this characteristic can contribute to understand the reproductive biology of the species. This study describes the histology and histochemistry of the spermatheca of T. lecticularia. Females have a pair of elongated spermathecal reservoirs without associated accessory gland. The reservoir opens into the common oviduct via a narrow muscular duct. The reservoir epithelium has single layer of columnar secretory cells. The control of the release of spermatozoa from the spermatheca occurs via the muscular duct. The anatomical features of the spermatheca of T. lecticularia resemble those described of other Reduviidae. However, the histological and histochemical features of spermatheca observed in T. lecticularia were important to explain the maintenance of the viability of the spermatozoa stored.


Assuntos
Triatoma/fisiologia , Animais , Feminino , Masculino , Reprodução , Espermatozoides/citologia , Espermatozoides/fisiologia , Triatoma/citologia
5.
Braz. j. biol ; 77(2): 284-288, Apr.-June 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888736

RESUMO

Abstract The antennal sensilla are sensory organs formed by a group of neurons and accessory cells, which allow perception of environmental cues, which play a role as mechanoreceptors and chemoreceptors. This study describes the post-embryonic development of the antennal sensilla of the stingless Tetragonisca angustula (Hymenoptera: Meliponini) workers. The development of the antennal sensilla begins in the transition stage of the pre-pupae to white-eyed pupae. The sensilla are completely developed at the black-eyed pupae stage, but they are covered by the old cuticle. The sensilla are exposed to the environment only in newly emerged workers of T. angustula, but it is possible that environmental stimuli can be recognized due to the pores in the old cuticle.


Resumo As sensilas antenais são órgãos sensoriais formados por um conjunto de neurônios que captam estímulos ambientais e células acessórias, desempenhando as funções de mecanorreceptores e quimiorrecepterores. Este trabalho descreve o desenvolvimento pós-embrionário das sensilas antenais de operárias das abelhas sem ferrão Tetragonisca angustula (Hymenoptera: Meliponini). O desenvolvimento das sensilas tem início na transição de pré-pupa para pupa de olho branco e estão completamente desenvolvidas no estágio de pupa de olho preto, mas ainda estão cobertas pela cutícula velha. As sensilas estão completamente expostas em operárias recém-emergidas de T. angustula, mas é possível que estímulos ambientais sejam percebidos em estágios anteriores devido aos poros presentes na cutícula velha.


Assuntos
Animais , Abelhas/crescimento & desenvolvimento , Sensilas/crescimento & desenvolvimento , Pupa/anatomia & histologia , Pupa/crescimento & desenvolvimento , Pupa/ultraestrutura , Abelhas/anatomia & histologia , Abelhas/ultraestrutura , Microscopia Eletrônica de Varredura , Sensilas/anatomia & histologia , Sensilas/ultraestrutura
6.
Braz J Biol ; 77(2): 284-288, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27599099

RESUMO

The antennal sensilla are sensory organs formed by a group of neurons and accessory cells, which allow perception of environmental cues, which play a role as mechanoreceptors and chemoreceptors. This study describes the post-embryonic development of the antennal sensilla of the stingless Tetragonisca angustula (Hymenoptera: Meliponini) workers. The development of the antennal sensilla begins in the transition stage of the pre-pupae to white-eyed pupae. The sensilla are completely developed at the black-eyed pupae stage, but they are covered by the old cuticle. The sensilla are exposed to the environment only in newly emerged workers of T. angustula, but it is possible that environmental stimuli can be recognized due to the pores in the old cuticle.


Assuntos
Abelhas/crescimento & desenvolvimento , Sensilas/crescimento & desenvolvimento , Animais , Abelhas/anatomia & histologia , Abelhas/ultraestrutura , Microscopia Eletrônica de Varredura , Pupa/anatomia & histologia , Pupa/crescimento & desenvolvimento , Pupa/ultraestrutura , Sensilas/anatomia & histologia , Sensilas/ultraestrutura
7.
Nat Commun ; 7: 12191, 2016 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-27412813

RESUMO

Black phosphorus has recently emerged as a new layered crystal that, due to its peculiar and anisotropic crystalline and electronic band structures, may have important applications in electronics, optoelectronics and photonics. Despite the fact that the edges of layered crystals host a range of singular properties whose characterization and exploitation are of utmost importance for device development, the edges of black phosphorus remain poorly characterized. In this work, the atomic structure and behaviour of phonons near different black phosphorus edges are experimentally and theoretically studied using Raman spectroscopy and density functional theory calculations. Polarized Raman results show the appearance of new modes at the edges of the sample, and their spectra depend on the atomic structure of the edges (zigzag or armchair). Theoretical simulations confirm that the new modes are due to edge phonon states that are forbidden in the bulk, and originated from the lattice termination rearrangements.

8.
Braz. j. biol ; 76(2): 396-401, Apr.-June 2016. tab
Artigo em Inglês | LILACS | ID: lil-781383

RESUMO

Abstract The effects of seasonal variations and the methods of collection of propolis produced by Africanized honey bees Apis mellifera Linnaeus, 1758, on the composition of constituent minerals such as magnesium (Mg), zinc (Zn), iron (Fe), sodium (Na), calcium (Ca), copper (Cu), and potassium (K) were evaluated. Propolis was harvested from 25 beehives by scraping or by means of propolis collectors (screen, “intelligent” collector propolis [ICP], lateral opening of the super [LOS], and underlay method). During the one-year study, the propolis produced was harvested each month, ground, homogenized, and stored in a freezer at -10 ºC. Seasonal analyses of the mineral composition were carried out by atomic absorption spectrophotometry and the results were evaluated by analysis of variance (ANOVA), followed by Tukey-Kramer’s test to compare the mean values (p<0.05). The results showed that seasonal variations influence the contents of 5 minerals (Mg, Fe, Na, Ca, and Cu), and the propolis harvesting method affects the contents of 4 minerals (Mg, Zn, Fe, and Ca).


Resumo A influência da sazonalidade e de métodos de produção de própolis por abelhas africanizadas Apis mellifera Linnaeus, 1758, sobre a concentração de magnésio (Mg), zinco (Zn), ferro (Fe), sódio (Na), cálcio (Ca), cobre (Cu) e potássio (K) foram avaliados. 25 colmeias foram utilizadas, e a colheita de propolis ocorreu por raspagem ou a partir de coletores (tela, coletor de própolis “inteligente” – CPI, abertura lateral da melgueira – ALM e calço). Durante um ano a própolis foi colhida mensalmente, homogeneizada e armazenada em freezer a -10 ºC. A análise sazonal de minerais foi realizada por espectrofotometria de absorção atômica e os resultados avaliados por análise de variância (ANOVA) seguida do teste de Tukey-Kramer para comparação de médias (p<0,05). Os resultados demostraram que a sazonalidade afetou o conteúdo de cinco minerais (Mg, Fe, Na, Ca e Cu) e os métodos de coleta afetaram o conteúdo de quatro minerais (Mg, Zn, Fe e Ca).


Assuntos
Animais , Própole/química , Estações do Ano , Abelhas , Minerais/análise , Potássio/análise , Sódio/análise , Espectrofotometria Atômica , Zinco/análise , Cálcio/análise , Cobre/análise , Ferro/análise , Magnésio/análise
9.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173211

RESUMO

The Colletotrichum genus presents large genetic variability, as demonstrated by the occurrence of several pathogenic races and phenotypic traits. The objective of this study was to characterize 22 strains of C. lindemuthianum and Colletotrichum spp recovered from anthracnose lesions and bean scab, and to verify the relationship between species of the Colletotrichum genus, which inhabit anthracnose and scab lesions. Colony morphology, conidium size, the presence of septa, germination, sporulation, and mycelium growth rates, were analyzed in addition to the presence of mating-type genes, IRAP markers, and pathogenicity. Strains of Colletotrichum spp presented wide variation for all evaluated traits, indicating the presence of different species. Pathogenicity tests verified that the severity of the disease caused by strains of Colletotrichum spp must be evaluated 17 days after inoculation. Molecular analysis showed that only the C. lindemuthianum strains were grouped by the IRAP markers. For the physiological traits, we observed that C. lindemuthianum mycelium growth is slower than that of Colletotrichum spp strains. The information generated in this study confirms variability in the evaluated species of Colletotrichum and may direct future basic and applied studies aiming to control these diseases in common bean.


Assuntos
Colletotrichum/genética , Phaseolus/microbiologia , Polimorfismo Genético , Colletotrichum/patogenicidade , Genes Fúngicos Tipo Acasalamento , Retroelementos , Virulência/genética
10.
Braz J Biol ; 76(2): 396-401, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26934152

RESUMO

The effects of seasonal variations and the methods of collection of propolis produced by Africanized honey bees Apis mellifera Linnaeus, 1758, on the composition of constituent minerals such as magnesium (Mg), zinc (Zn), iron (Fe), sodium (Na), calcium (Ca), copper (Cu), and potassium (K) were evaluated. Propolis was harvested from 25 beehives by scraping or by means of propolis collectors (screen, "intelligent" collector propolis [ICP], lateral opening of the super [LOS], and underlay method). During the one-year study, the propolis produced was harvested each month, ground, homogenized, and stored in a freezer at -10 ºC. Seasonal analyses of the mineral composition were carried out by atomic absorption spectrophotometry and the results were evaluated by analysis of variance (ANOVA), followed by Tukey-Kramer's test to compare the mean values (p<0.05). The results showed that seasonal variations influence the contents of 5 minerals (Mg, Fe, Na, Ca, and Cu), and the propolis harvesting method affects the contents of 4 minerals (Mg, Zn, Fe, and Ca).


Assuntos
Abelhas , Minerais/análise , Própole/química , Estações do Ano , Animais , Cálcio/análise , Cobre/análise , Ferro/análise , Magnésio/análise , Potássio/análise , Sódio/análise , Espectrofotometria Atômica , Zinco/análise
11.
Sci Rep ; 6: 20644, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26856886

RESUMO

We demonstrated a method to construct high efficiency saturable absorbers based on the evanescent light field interaction of CVD monolayer graphene deposited on side-polished D-shaped optical fiber. A set of samples was fabricated with two different core-graphene distances (0 and 1 µm), covered with graphene ranging between 10 and 25 mm length. The mode-locking was achieved and the best pulse duration was 256 fs, the shortest pulse reported in the literature with CVD monolayer graphene in EDFL. As result, we find a criterion between the polarization relative extinction ratio in the samples and the pulse duration, which relates the better mode-locking performance with the higher polarization extinction ratio of the samples. This criterion also provides a better understanding of the graphene distributed saturable absorbers and their reproducible performance as optoelectronic devices for optical applications.

12.
Genet Mol Res ; 14(2): 5044-53, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-26125696

RESUMO

The fungus Pseudocercospora griseola, the causal agent of angular leaf spot in the common bean (Phaseolus vulgaris L.), exhibits a broad pathogenic variability that complicates the development of resistant cultivars. For breeding programs to successfully obtain common bean cultivars with durable resistance, knowing the aggressiveness of different strains, as well as the mechanisms of genetic resistance, is important. The aims of this study were to study the variation within race 63.63 by evaluating the aggressiveness of different strains, to analyze the genetic resistance of common bean lines to P. griseola, and to ascertain the implications for genetic improvement in obtaining resistance in this pathosystem. Four strains, collected from different locations, were inoculated in three groups of common bean lines in a greenhouse, and the severity of the disease was subsequently evaluated. Statistical analyses were carried out using the diallel method, which provided information on the vertical and horizontal resistance of host plants, in addition to information regarding the aggressiveness of the strains. The aggressiveness of P. griseola differed between the strains of race 63.63. The diallel method proved to be promising for the identification of horizontal and vertical resistance in the common bean-P. griseola pathosystem, with a predominance of horizontal resistance. Gene pyramiding, using marker-assisted selection, may not be the most effective strategy for obtaining durable resistance.


Assuntos
Ascomicetos/patogenicidade , Resistência à Doença/genética , Phaseolus/genética , Doenças das Plantas/genética , Locos de Características Quantitativas , Ascomicetos/crescimento & desenvolvimento , Cruzamento , Resistência à Doença/imunologia , Genótipo , Interações Hospedeiro-Patógeno , Phaseolus/imunologia , Phaseolus/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/microbiologia , Seleção Genética
13.
Genet Mol Res ; 14(3): 7436-45, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26214422

RESUMO

The fungus Pseudocercospora griseola is the causal agent of angular leaf spot, a common bean (Phaseolus vulgaris L.) disease. The successful development of angular leaf spot-resistant cultivars depends on understanding the levels of variability in pathogen populations. P. griseola shows great pathogenic and genetic variation using inoculation on differential bean cultivars and molecular markers. Nevertheless, how this variability develops is not clearly understood. Parasexuality has been presented as a mechanism used by asexual fungi to increase variation. Hyphal fusion is the first step for the parasexual cycle, and it can be considered an additional trait for population studies. The aim of this study was to identify hyphal fusion (anastomosis) among P. grisola isolates and to evaluate the variability of isolates using analyses of anastomosis groups and RAPD markers. Hyphal anastomosis was observed in all isolates. Three isolates showed 85.0% compatibility and were compatible with 17 isolates. This is the first report of the occurrence of anastomosis between P. griseola isolates. Sixteen anastomosis groups were observed and only one group was formed by five isolates (Pg-01, Pg-02, Pg-07, Pg-08, and Pg-12). There was a large number of anastomosis groups and absence of clustering among isolates for hyphal fusion, demonstrating the existence of genetic variability for loci involved in the control of this trait. High genotypic variability by RAPD markers was detected, but there was no relationship between genotype and anastomosis group. More studies are necessary to elucidate further the process of asexual recombination in this phytopathogen.


Assuntos
Ascomicetos/genética , Micoses/microbiologia , Phaseolus/microbiologia , Doenças das Plantas/microbiologia , Ascomicetos/metabolismo , Estudos de Associação Genética , Variação Genética , Hifas/genética , Hifas/metabolismo , Folhas de Planta/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos
14.
Genet Mol Res ; 14(2): 6879-96, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26125896

RESUMO

White mold is a common bean disease caused by the fungus Sclerotinia sclerotiorum, resulting in economic losses in Brazil and worldwide. Lack of knowledge about the population structure of the pathogen makes it difficult to control the disease. The aim of this study was to characterize strains of S. sclerotiorum obtained from ex-perimental and commercial common bean fields in Brazil. We analyzed 50 strains of S. sclerotiorum collected at several locations in the state of Minas Gerais. The strains were characterized according to their ability and time for developing apothecia. Morphological and physiological analyses such as the mycelial growth index, colony color, the time re-quired to form the first sclerotia on media, the number of sclerotia per plate, average sclerotium size, and sclerotium shape were performed. We determined the mycelial compatibility, conducted molecular analy-sis of microsatellites, and evaluated the aggressiveness of 28 strains. Most strains had the ability to form apothecia. A small group of strains showed mycelial compatibility, and the strains showed different aggres-siveness levels. Overall, the population studied here demonstrated wide variability based on the morphological, physiological, and molecular traits analyzed. The average size and shape of sclerotia presented a cor-relation of 0.617, whereas the times required to form sclerotia and the number of sclerotia per plate showed a correlation of -0.455. The char-acterization of the pathogen population described herein will provide an important tool for promoting the development of bean cultivars re-sistant to white mold.


Assuntos
Ascomicetos/genética , Ascomicetos/patogenicidade , DNA Fúngico/genética , Variação Genética , Micélio/genética , Ascomicetos/classificação , Ascomicetos/ultraestrutura , Brasil , Repetições de Microssatélites , Micélio/ultraestrutura , Phaseolus/microbiologia , Filogenia , Doenças das Plantas/microbiologia
15.
Opt Lett ; 37(24): 5211-3, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23258055

RESUMO

We present a study of pulse generation and propagation in erbium-doped fiber lasers with cavity length varying from 8 m to 3.5 km. We demonstrate that soliton effect determines the pulse stabilization in ultralong cavities, measuring pulses with an average 7.0 ps pulsewidth for cavity lengths between 2.25 and 3.5 km. We also demonstrate that, by filling fundamental soliton requirements, pulsewidth can be determined by length and total dispersion cavity parameters.

16.
Phytopathology ; 102(5): 490-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22250759

RESUMO

Colletotrichum lindemuthianum, causal agent of anthracnose in the common bean, has wide genetic variability. Differential bean cultivars and morphological and physiological characteristics were used to analyze 74 isolates of C. lindemuthianum collected in two counties in the state of Minas Gerais, Brazil. Six different races were found, with a predominance of race 65 at both locations. Isolates were classified according to their sensitivities to the fungicide thiophanate-methyl, normally used in the control of common bean anthracnose. In all, ≈10% of isolates were resistant to the fungicide in vitro. Characteristics such as indexes of mycelia growth rate, colony diameter, sporulation capacity, and percentage of germination demonstrated the high genetic variability of C. lindemuthianum. We also observed variation in conidial cytology. The conidia of most isolates showed septa formation after germination, in contrast to septa absence, previously reported in the literature. Sexual and asexual reproduction were evaluated for mechanisms that may contribute in the generation of variability in C. lindemuthianum. Conidial anastomosis tubes were commonly found, indicating that asexual reproduction can help increase variability in this species. Information from this study confirmed high variability in C. lindemuthianum and will guide future studies in basic knowledge and applied technologies.


Assuntos
Colletotrichum/classificação , Fungicidas Industriais/farmacologia , Variação Genética/fisiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos/citologia , Tiofanato/farmacologia , Brasil , Colletotrichum/efeitos dos fármacos , Colletotrichum/patogenicidade , Colletotrichum/fisiologia , Farmacorresistência Fúngica , Fabaceae/microbiologia , Fenótipo , Reação em Cadeia da Polimerase , Fatores de Tempo
17.
Artigo em Inglês | MEDLINE | ID: mdl-22243444

RESUMO

The increasing use of antimicrobial agents such as sulfonamides by the pig industry is of concern, since residues in both pork and its by-products, when derived from animals treated improperly, can endanger human health. The aim of this study was to establish the production conditions and to evaluate the homogeneity and the stability of sulfamethazine in porcine liver quality control material, produced 'in-house' for use in ring tests of the laboratory network of residues and contaminants of the Ministry of Agriculture, Livestock and Food Supply, Brazil. In the process of preparing the material, a FOSS blender was used, where the samples were ground to obtain a homogeneous mass, which was packed in polypropylene bottles. The material resulting from this process of homogenisation was sampled and analysed by LC/MS/MS. The analytical results were statistically evaluated by one-way ANOVA. According to statistical evaluation, the material produced was considered homogeneous, with 95% confidence. Stability tests were performed with the bottles stored under the specified storage conditions. They were randomly selected and analysed in duplicate by the same analytical method as the homogeneity study. The analytical results were statistically evaluated by the procedures for a stability check described in ISO 13528:2005, indicating that the material was unstable under the conditions of storage.


Assuntos
Anti-Infecciosos/análise , Contaminação de Alimentos/análise , Sulfametazina/análise , Animais , Anti-Infecciosos/normas , Brasil , Cromatografia Líquida , Resíduos de Drogas/análise , Resíduos de Drogas/normas , Contaminação de Alimentos/legislação & jurisprudência , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/estatística & dados numéricos , Inocuidade dos Alimentos , Humanos , Fígado/química , Carne/análise , Controle de Qualidade , Padrões de Referência , Sulfametazina/normas , Sus scrofa , Espectrometria de Massas em Tandem , Drogas Veterinárias/análise , Drogas Veterinárias/normas
18.
Genet Mol Res ; 10(1): 230-42, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21341215

RESUMO

The causal agent of common bean anthracnose, Colletotrichum lindemuthianum, has considerable genetic and pathogenic variability, which makes the development of resistant cultivars difficult. We examined variability within and between Brazilian pathotypes of C. lindemuthianum through the identification of vegetative compatibility groups (VCGs) and by RAPD analysis. Two hundred and ninety-five nit mutants were obtained from 47 isolates of various pathotypes of the fungus collected from different regions, host cultivars and years. In complementation tests, 45 VCGs were identified. Eighteen RAPD primers were employed in the molecular analyses, producing 111 polymorphic bands. Estimates of genetic similarities, determined from the Sorence-Dice coefficient, ranged from 0.42 to 0.97; the dendrogram obtained by cluster analysis revealed 18 groups of isolates. RAPD and VCG markers presented high genotypic diversity. The number of significant associations (P=0.05) between RAPD, VCG and pathogenicity markers ranged from 0 (VCG) to 80% (pathogenicity). The test of multilocus association (rd) for RAPD markers was significantly different from zero (P<0.001), suggesting linkage disequilibrium. However, the results for VCG markers show the presence of recombination mechanisms. In conclusion, RAPD markers and VCGs were useful for detecting genetic variability among isolates of C. lindemuthianum. We found considerable diversity among isolates from the same geographic origin within a short interval; this suggests rapid evolution. There is a need for further studies to elucidate the population structure of this pathogen in agro-ecosystems.


Assuntos
Colletotrichum/genética , Brasil , Colletotrichum/patogenicidade , Fabaceae/microbiologia , Variação Genética/genética , Desequilíbrio de Ligação/genética , Doenças das Plantas/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico
19.
Arq. neuropsiquiatr ; 69(2b): 336-341, 2011. tab
Artigo em Inglês | LILACS | ID: lil-588095

RESUMO

It is assumed that 25 percent of patients with epilepsy are women of fertile age and 0.3 percent to 0.6 percent of all children are born of mothers with epilepsy. The aim of this study was to evaluate the quality of life on pregnant with epilepsy and compare with non-pregnant women with epilepsy. We evaluated two groups (Experimental Group - 29 pregnant women with epilepsy and Control Group - 30 women with epilepsy); they were attended at the HC/UNICAMP. The patients had three meetings to carry out and implement the anamnesis and the application of QQV-65. There were no significant differences in the measurement of quality of life when comparing both groups. However, when we analyzed individually in the pre- and post-partum periods, we observed significant differences in health aspects (p=0.0495), physical (p=0.02868) and emotional (p=0.0253) dimensions in QQV-65. This study shows that pregnancy could be interpreted as a stressor. In late pregnancy when this stressor was removed, women with epilepsy had improvement in their quality of life.


Admite-se que 25 por cento dos pacientes com epilepsia sejam mulheres em idade fértil e que 0,3 por cento a 0,6 por cento de todas as crianças nascidas sejam filhas de mães epilépticas. O objetivo do presente estudo foi avaliar a qualidade de vida em gestantes com epilepsia e compará-la com a de mulheres com epilepsia não grávidas. Foram avaliados dois grupos (Grupo Experimental - 29 gestantes com epilepsia e Grupo Controle - 30 mulheres com epilepsia) atendidos no HC/UNICAMP. As pacientes foram submetidas a três encontros para a realização de anamnese e a aplicação do QQV-65. Não encontramos diferenças significativas na avaliação de qualidade de vida ao comparar ambos os grupos. No entanto quando avaliados individualmente no período pré e pós-natal, observamos diferenças significativas nos aspectos: saúde (p=0,0495), físico (p=0,02868) e emocional (p=0,0253) no QQV-65. Este estudo mostrou que a gravidez pode ser interpretada como um estressor. No final da gravidez, quando este estressor foi removido, mulheres com epilepsia mostraram melhora na qualidade de vida.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Gravidez , Adulto Jovem , Epilepsia/psicologia , Complicações na Gravidez/psicologia , Qualidade de Vida/psicologia , Estudos de Casos e Controles , Fatores Socioeconômicos , Inquéritos e Questionários
20.
Genet Mol Res ; 9(3): 1759-69, 2010 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-20830667

RESUMO

Glomerella cingulata f. sp phaseoli is the sexual phase of the fungus Colletotrichum lindemuthianum, the causal agent of common bean anthracnose. This fungus is of great concern, because it causes large economic losses in common bean crops. RAPD markers of five populations of G. cingulata f. sp phaseoli from two Brazilian states were analyzed to determine if this population possesses the sexual reproductive potential to generate the genetic variation that is observed in this phytopathogen. We identified 128 polymorphic bands, amplified by 28 random primers. The estimates of genetic similarity in this analysis ranged from 0.43 to 1.00, and the dendrogram generated from analysis of all genotypes displayed five principal groups, coinciding with the five populations. Genetic differentiation was observed between the populations (GST=0.6455); 69% of the overall observed genetic variation was between individual populations and 31% of the variance was within the sub-populations. We identified significant levels of linkage disequilibrium in all populations. However, the values of the disequilibrium ranged from low to moderate, indicating that this pathogen maintains a genetic structure consistent with sexual reproduction. The mean contribution of sexual reproduction was determined by comparison of the amplitudes of genetic similarity of isolates from sexual and asexual phases. These results support the hypothesis that recombination plays an important role in determining the amplitude of variability in this pathogen population and that this determination occurs on a fine scale.


Assuntos
Colletotrichum/crescimento & desenvolvimento , Colletotrichum/genética , Análise por Conglomerados , Colletotrichum/isolamento & purificação , Fabaceae/microbiologia , Variação Genética/genética , Desequilíbrio de Ligação/genética , Doenças das Plantas/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico
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