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1.
Planta ; 258(1): 5, 2023 May 23.
Article in English | MEDLINE | ID: mdl-37219749

ABSTRACT

MAIN CONCLUSION: An exonuclease V homologue from apomictic Brachiaria brizantha is expressed and localized in nucellar cells at key moments when these cells differentiate to give rise to unreduced gametophytes. Brachiaria is a genus of forage grasses with economical and agricultural importance to Brazil. Brachiaria reproduces by aposporic apomixis, in which unreduced embryo sacs, derived from nucellar cells, other than the megaspore mother cell (MMC), are formed. The unreduced embryo sacs produce an embryo without fertilization resulting in clones of the mother plant. Comparative gene expression analysis in ovaries of sexual and apomictic Brachiaria spp. revealed a sequence from B. brizantha that showed a distinct pattern of expression in ovaries of sexual and apomictic plants. In this work, we describe a gene named BbrizExoV with strong identity to exonuclease V (Exo V) genes from other grasses. Sequence analysis in signal prediction tools showed that BbrizExoV might have dual localization, depending on the translation point. A longer form to the nucleus and a shorter form which would be directed to the chloroplast. This is also the case for monocot sequences analyzed from other species. The long form of BbrizExoV protein localizes to the nucleus of onion epidermal cells. Analysis of ExoV proteins from dicot species, with exception of Arabidopsis thaliana ExoVL protein, showed only one localization. Using a template-based AlphaFold 2 modelling approach the structure of BbrizExoV in complex with metal and ssDNA was predicted based on the holo structure of the human counterpart. Features predicted to define ssDNA binding but a lack of sequence specificity are shared between the human enzyme and BbrizExoV. Expression analyses indicated the precise site and timing of transcript accumulation during ovule development, which coincides with the differentiation of nucelar cells to form the typical aposporic four-celled unreduced gametophyte. A putative function for this protein is proposed based on its homology and expression pattern.


Subject(s)
Apomixis , Arabidopsis , Brachiaria , Humans , Exodeoxyribonuclease V , Gametogenesis, Plant , Germ Cells, Plant , Poaceae
2.
In. Osorio-de-Castro, Claudia Garcia Serpa; Luiza, Vera Lucia; Castilho, Selma Rodrigues de; Oliveira, Maria Auxiliadora; Jaramillo, Nelly Marin. Assistência farmacêutica: gestão e prática para profissionais da saúde. Rio de Janeiro, Editora Fiocruz, 2014. p.373-379.
Monography in Portuguese | LILACS | ID: lil-736640
3.
Plant Cell Rep ; 31(2): 403-16, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22068439

ABSTRACT

In apomixis, asexual mode of plant reproduction through seeds, an unreduced megagametophyte is formed due to circumvented or altered meiosis. The embryo develops autonomously from the unreduced egg cell, independently of fertilization. Brachiaria is a genus of tropical forage grasses that reproduces sexually or by apomixis. A limited number of studies have reported the sequencing of apomixis-related genes and a few Brachiaria sequences have been deposited at genebank databases. This work shows sequencing and expression analyses of expressed sequence-tags (ESTs) of Brachiaria genus and points to transcripts from ovaries with preferential expression at megasporogenesis in apomictic plants. From the 11 differentially expressed sequences from immature ovaries of sexual and apomictic Brachiaria brizantha obtained from macroarray analysis, 9 were preferentially detected in ovaries of apomicts, as confirmed by RT-qPCR. A putative involvement in early steps of Panicum-type embryo sac differentiation of four sequences from B. brizantha ovaries: BbrizHelic, BbrizRan, BbrizSec13 and BbrizSti1 is suggested. Two of these, BbrizSti1 and BbrizHelic, with similarity to a gene coding to stress induced protein and a helicase, respectively, are preferentially expressed in the early stages of apomictic ovaries development, especially in the nucellus, in a stage previous to the differentiation of aposporous initials, as verified by in situ hybridization.


Subject(s)
Apomixis/genetics , Brachiaria/embryology , Expressed Sequence Tags , Flowers/genetics , Genes, Plant/genetics , Morphogenesis/genetics , Seeds/embryology , Brachiaria/cytology , Brachiaria/genetics , Flowers/cytology , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Gene Library , In Situ Hybridization , Molecular Sequence Annotation , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Seeds/genetics
4.
Sex Plant Reprod ; 24(3): 231-46, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21394488

ABSTRACT

Apomixis, an asexual mode of reproduction through seeds, holds much promise for agricultural advances. However, the molecular mechanisms underlying this trait are still poorly understood. We previously isolated several transcripts representing novel sequences differentially expressed in reproductive tissues of sexual and apomictic plants. Here, we report the characterization of two of these unknown RNA transcripts (experimental codes N17 and N22). Since original fragments showed no significant homologies to sequences at databases, preliminary genomic PCR experiments were carried out to discard possible contaminations. RACE extension on flanking regions provided longer sequences for the candidates and additional related transcripts, which revealed similarity to LTR retrotransposons carrying short transduplicated segments of protein-coding genes. Interestingly, some transduplicated segments corresponded to genes previously associated with apomictic development. Gene copy number estimations revealed a moderate representation of the elements in the genome, with significantly increased numbers in a sexual genotype with respect to an apomictic one. Genetic mapping of N17 showed that a copy of this particular element was located onto Paspalum notatum linkage group F3c, at a central non-recombinant region resembling a centromere. Expression analysis showed an increased activity of N17 and N22 sense strands in ovules of the sexual genotypes. A retrotransposon-specific differential display analysis aimed at detecting related sequences allowed the identification of a complex family, with the majority of its members represented in the sexual genotype. Our results suggest that these elements could be participating in regulatory pathways related to apomixis and sexuality.


Subject(s)
Flowering Tops/metabolism , Paspalum/metabolism , Retroelements , Chromosome Mapping , Gene Dosage , Genome, Plant , In Situ Hybridization , Nucleic Acid Amplification Techniques , Paspalum/genetics , Reproduction, Asexual
5.
Fisioter. pesqui ; 17(4): 327-331, out.-dez. 2010. tab, graf
Article in Portuguese | LILACS | ID: lil-587975

ABSTRACT

O objetivo do estudo foi comparar o desempenho funcional de idosas segundo a medida de suas circunfêrencias abdominais (CA). Foram avaliadas 48 idosas, divididas nos grupos 1, com CA>88 cm, e grupo 2, de CA<88 cm. A funcionalidade foi avaliada pelo teste de caminhada de seis minutos (TC6') e pelo teste de desempenho físico modificado (TDFM), não-dependente de condicionamento cardiovascular. O grupo 1, cujos valores de peso e índice de massa corporal foram estatisticamente superiores (p<0,05) aos do grupo 2, percorreu distância média menor, quando comparado ao grupo 2 (p<0,05), e obteve escores médios inferiores no TDFM (p<0,05). Os dados mostram que mulheres idosas com circunferência abdominal superior a 88 cm tiveram pior desempenho nos testes funcionais, sugerindo que a obesidade abdominal pode contribuir para o declínio funcional precoce e conseqüente incapacidade nessa população.


The purpose of this study was to compare physical performance of elderly women according to their waist circumference (WC). Forty-eight elderly women were divided into group 1, with WC>88 cm, and group 2, with WC<88 cm. Physical function was assessed by means of the six-minute walk test (6MWT) and by the modified physical performance test (MPPT), non-dependent on physical fitness. Group 1 mean body mass and body mass index measures were statistically higher (p<0.05) than group 2's; group 1 also walked significantly shorter mean distances than group 2 (p<0.05), and scored lower at the MPPT (p<0.05). Data thus show that elderly women with over 88 cm waist circumference had poor performance at physical function tests, suggesting that the presence of visceral obesity may contribute to functional decline and further impairment among elderly women.


Subject(s)
Humans , Female , Middle Aged , Abdominal Circumference , Frail Elderly , Obesity , Sarcopenia , Women
6.
Rev Soc Bras Med Trop ; 43(2): 198-200, 2010.
Article in Portuguese | MEDLINE | ID: mdl-20464153

ABSTRACT

INTRODUCTION: Cryptococcus neoformans is an encapsulated yeast and is the etiological agent for human and animal cryptococcosis. It is found in sources within the environment, including pigeon excrement, and is an important cause of mortality among immunocompromised individuals worldwide. METHODS: Seventy different environments in the city of Pelotas, Rio Grande do Sul, were surveyed for the purpose of investigating Cryptococcus neoformans occurrences in pigeon excreta. The environments included buildings, public squares and outdoor locations in the city. After collection, chloramphenicol saline solution was added to the excreta, which were then homogenized and seeded onto Sabouraud agar with chloramphenicol and onto Niger agar, and incubated at 32 degrees C. Identification was performed by direct examination and by means of the phenoloxidase and urease tests, carbohydrate assimilation and culturing in CGB medium. RESULTS: Out of the sites investigated (n = 70), 26 (37.1%) of them contained pigeon excreta. These included historical buildings (n = 8), a church tower (n = 1), rice mills and warehouses (n = 7), a public square (n = 1) and outdoor locations (n = 9). Cryptococcus neoformans was isolated from 26.9% (n = 7/26) of these locations. CONCLUSIONS: This study draws attention to isolation of this fungus in urban areas that present large accumulations of pigeon excrement. This represents a risk to public health, especially for immunocompromised individuals.


Subject(s)
Columbidae/microbiology , Cryptococcus neoformans/isolation & purification , Feces/microbiology , Animals , Brazil , Urban Population
7.
Rev. Soc. Bras. Med. Trop ; 43(2): 198-200, Mar.-Apr. 2010. tab
Article in Portuguese | LILACS | ID: lil-545776

ABSTRACT

INTRODUÇÃO: O Cryptococcus neoformans é uma levedura capsulada, agente etiológico da criptococose em humanos e animais, encontrado em fontes ambientais, incluindo excretas de pombos, é uma importante causa de mortalidade em indivíduos imunodeprimidos em todo o mundo. MÉTODOS: Com o objetivo de verificar a ocorrência do Cryptococcus neoformans, em excretas de pombos, na Cidade de Pelotas, pesquisou-se 70 ambientes, incluindo prédios, praças e locais ao ar livre, da Cidade de Pelotas, RS. Após a coleta, os excrementos foram adicionados de salina com cloranfenicol, homogeneizados, semeados em ágar Sabouraud com cloranfenicol e ágar Níger e incubados a 32ºC. Para identificação, realizou-se exame direto, prova da fenoloxidase, urease, assimilação de carboidratos e cultura em meio CGB. RESULTADOS: Dos locais estudados (nº =70), em 26 (37,1 por cento) havia excretas de pombos. Estes lugares foram representados por prédios históricos (nº =8), torre de igreja (nº =1), engenhos e armazéns de arroz (nº =7), praça (nº =1) e locais ao ar livre (nº =9), o isolamento de Cryptococcus neoformans ocorreu em 26,9 por cento (nº =7/26), destes locais. CONCLUSÕES: O estudo chama a atenção, para o isolamento do fungo em áreas urbanas, que apresentavam grande acúmulo de excretas, indicando um risco para a saúde pública, especialmente para indivíduos imunocomprometidos.


INTRODUCTION: Cryptococcus neoformans is an encapsulated yeast and is the etiological agent for human and animal cryptococcosis. It is found in sources within the environment, including pigeon excrement, and is an important cause of mortality among immunocompromised individuals worldwide. METHODS: Seventy different environments in the city of Pelotas, Rio Grande do Sul, were surveyed for the purpose of investigating Cryptococcus neoformans occurrences in pigeon excreta. The environments included buildings, public squares and outdoor locations in the city. After collection, chloramphenicol saline solution was added to the excreta, which were then homogenized and seeded onto Sabouraud agar with chloramphenicol and onto Niger agar, and incubated at 32°C. Identification was performed by direct examination and by means of the phenoloxidase and urease tests, carbohydrate assimilation and culturing in CGB medium. RESULTS: Out of the sites investigated (n = 70), 26 (37.1 percent) of them contained pigeon excreta. These included historical buildings (n = 8), a church tower (n = 1), rice mills and warehouses (n = 7), a public square (n = 1) and outdoor locations (n = 9). Cryptococcus neoformans was isolated from 26.9 percent (n = 7/26) of these locations. CONCLUSIONS: This study draws attention to isolation of this fungus in urban areas that present large accumulations of pigeon excrement. This represents a risk to public health, especially for immunocompromised individuals.


Subject(s)
Animals , Columbidae/microbiology , Cryptococcus neoformans/isolation & purification , Feces/microbiology , Brazil , Urban Population
8.
BMC Plant Biol ; 9: 84, 2009 Jul 02.
Article in English | MEDLINE | ID: mdl-19573233

ABSTRACT

BACKGROUND: Brachiaria brizantha is an important forage grass. The occurrence of both apomictic and sexual reproduction within Brachiaria makes it an interesting system for understanding the molecular pathways involved in both modes of reproduction. Quantitative real time PCR (qRT-PCR) has emerged as an important technique to compare expression profile of target genes and, in order to obtain reliable results, it is important to have suitable reference genes. In this work, we evaluated eight potential reference genes for B. brizantha qRT-PCR experiments, isolated from cDNA ovary libraries. Vegetative and reproductive tissues of apomictic and sexual B. brizantha were tested to validate the reference genes, including the female gametophyte, where differences in the expression profile between sexual and apomictic plants must occur. RESULTS: Eight genes were selected from a cDNA library of ovaries of B. brizantha considering the similarity to reference genes: EF1 (elongation factor 1 alpha), E1F4A (eukaryotic initiation factor 4A), GAPDH (glucose-6-phosphate dehydrogenase), GDP (glyceroldehyde-3-phosphate dehydrogenase), SUCOA (succinyl-CoA ligase), TUB (tubulin), UBCE (ubiquitin conjugating enzyme), UBI (ubiquitin). For the analysis, total RNA was extracted from 22 samples and raw Ct data after qRT-PCR reaction was analyzed for primer efficiency and for an overall analysis of Ct range among the different samples. Elongation factor 1 alpha showed the highest expression levels, whereas succinyl-CoA ligase showed the lowest within the chosen set of samples. GeNorm application was used for evaluation of the best reference genes, and according to that, the least stable genes, with the highest M values were tubulin and succinyl-CoA ligase and the most stable ones, with the lowest M values were elongation factor 1 alpha and ubiquitin conjugating enzyme, when both reproductive and vegetative samples were tested. For ovaries and spikelets of both sexual and apomictic B. brizantha the genes with the lowest M values were BbrizUBCE, BbrizE1F4A and BbrizEF1. CONCLUSION: In total, eight genes belonging to different cellular processes were tested. Out of them, BbrizTUB was the less stable while BbrizEF1 followed by BbrizUBCE were the more stable genes considering male and female reproductive tissues, spikelets, roots and leaves. Regarding the best reference genes for ovary tissues, where apomictic and sexual reproduction must occur, the best reference genes were BbrizUBCE, BbrizE1F4A and BbrizEF1. Our results provide crucial information for transcriptional analysis in the Brachiaria ssp, helping to improve the quality of gene expression data in these species, which constitute an excellent plant system for the study of apomixis.


Subject(s)
Brachiaria/genetics , Gene Expression Profiling/methods , Reverse Transcriptase Polymerase Chain Reaction/standards , Brachiaria/growth & development , DNA Primers , Flowers/genetics , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Gene Library , Genes, Plant , Plant Leaves/genetics , Plant Proteins/genetics , Plant Roots/genetics , RNA, Plant/genetics , Reproduction/genetics , Sequence Analysis, DNA
9.
Rev. bras. ciênc. vet ; 12(1/3): 99-101, jan.-dez. 2005. ilus
Article in Portuguese | LILACS | ID: lil-435914

ABSTRACT

A esporotricose é uma micose subcutânea resultante da inoculação do fungo Sporothrix schenckii na pele e tecido subcutâneo. Micoses como a esporotricose podem comportar-se de forma oportunista em indivíduos imunossuprimidos. O presente trabalho teve como objetivo relacionar esporotricose e vírus da leucemia felina (FeLV) em 18 gatos, de um total de 90 criados em ambiente úmido, cercado por vegetação e pouca incidência solar. Para o diagnóstico micológico foram colhidos fragamentos e exsudato das lesões e para o diagnóstico da FeLV, pela técnica de imunofluorescência indireta, colheu-se sangue. A FeLV foi pesquisada em 18 gatos com esporotricose. Quatro animais (22,2


Subject(s)
Cats , Leukemia , Leukemia Virus, Feline , Sporotrichosis
10.
Rev. bras. ciênc. vet ; 12(1-3): 1-3, 2005.
Article in Portuguese | LILACS-Express | LILACS, VETINDEX | ID: biblio-1491305

ABSTRACT

A esporotricose é uma micose subcutânea resultante da inoculação do fungo Sporothrix schenckii na pele e tecido subcutâneo.Micoses como a esporotricose podem comportar-se de forma oportunista em indivíduos imunossuprimidos. O presentetrabalho teve como objetivo relacionar esporotricose e vírus da leucemia felina (FeLV) em 18 gatos, de um total de 90, criadosem ambiente úmido, cercado por vegetação e pouca incidência solar. Para o diagnóstico micológico foram colhidos fragmentose exsudato das lesões e para o diagnóstico da FeLV, pela técnica de imunofluorescência indireta, colheu-se sangue. A FeLVfoi pesquisada em 18 gatos com esporotricose. Quatro animais (22,2%) foram diagnosticados FeLV positivo, demonstrandoque há relação entre o animal portador de um vírus imunossupressor e o desenvolvimento da esporotricose, em conseqüência,principalmente, do contato contínuo e insalubre entre animais sadios e doente.

11.
Rev. bras. odontol ; 60(3): 161-163, maio-jun. 2003. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-404184

ABSTRACT

O adenoma pleomórfico é um tumor benigno de glândula salivar de crescimento lento, que acomete mais frequentemente a glândula parótida, composto por elementos ductais e mioepiteliais. Apresenta-se clinicamente como uma lesão assintomática e, quando acomete as glândulas salivares menores, raramente atinge diâmetro superior a 2cm. Este trabalho relata um caso clínico de adenoma pleomórfico, em lábio superior, em um paciente do sexo masculino com 25 anos


Subject(s)
Humans , Male , Adult , Adenoma, Pleomorphic , Salivary Glands, Minor/pathology , Lip
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