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2.
J Appl Microbiol ; 131(4): 2049-2060, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33694241

RESUMO

AIMS: The aim of this study was to evaluate the formation of biofilm by Candida spp. isolated from the bloodstream, using traditional spectrophotometric methodologies. In addition, the goal was to compare the results with those obtained through MALDI-TOF/MS, as well as to verify its use as a potential tool for the detection of biofilm-forming strains. METHODS AND RESULTS: Hundred and thirteen isolates of Candida spp. were studied: 41 were Candida albicans, 27 C. tropicalis, 18 C. glabrata, 17 C. parapsilosis and 10 C. krusei. Metabolic activity was determined through the tetrazolium salt (XTT) reduction assay and biomass by staining with Crystal Violet. All isolates were able to form biofilm, 94% of which were strong producers, with high biomass quantification (95%; 107/113) and high metabolic activity (99%; 112/113). Mass spectra of the biofilm-producing isolates showed differences in the intensity of mass peaks when compared with the spectra of the nonproducing strains. CONCLUSIONS: It was demonstrated that MALDI-TOF/MS was able to detect specific biofilm proteins, as the mass spectra of the isolates presented differences when compared with nonproducing strains. SIGNIFICANCE AND IMPACT OF THE STUDY: MALDI-TOF/MS can become a valuable tool for biofilm detection at the moment of the identification of the microorganism, thus contributing greatly to the management of patients with Candidemia.


Assuntos
Candida , Candidemia , Biofilmes , Candida albicans , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Sci Rep ; 11(1): 3710, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580108

RESUMO

In Rosaceae species, two gametophytic self-incompatibility (GSI) mechanisms are described, the Prunus self-recognition system and the Maleae (Malus/Pyrus/Sorbus) non-self- recognition system. In both systems the pistil component is a S-RNase gene, but from two distinct phylogenetic lineages. The pollen component, always a F-box gene(s), in the case of Prunus is a single gene, and in Maleae there are multiple genes. Previously, the Rosa S-locus was mapped on chromosome 3, and three putative S-RNase genes were identified in the R. chinensis 'Old Blush' genome. Here, we show that these genes do not belong to the S-locus region. Using R. chinensis and R. multiflora genomes and a phylogenetic approach, we identified the S-RNase gene, that belongs to the Prunus S-lineage. Expression patterns support this gene as being the S-pistil. This gene is here also identified in R. moschata, R. arvensis, and R. minutifolia low coverage genomes, allowing the identification of positively selected amino acid sites, and thus, further supporting this gene as the S-RNase. Furthermore, genotype-phenotype association experiments also support this gene as the S-RNase. For the S-pollen GSI component we find evidence for multiple F-box genes, that show the expected expression pattern, and evidence for diversifying selection at the F-box genes within an S-haplotype. Thus, Rosa has a non-self-recognition system, like in Maleae species, despite the S-pistil gene belonging to the Prunus S-RNase lineage. These findings are discussed in the context of the Rosaceae GSI evolution. Knowledge on the Rosa S-locus has practical implications since genes controlling floral and other ornamental traits are in linkage disequilibrium with the S-locus.


Assuntos
Evolução Biológica , Rosa/genética , Autoincompatibilidade em Angiospermas/genética , Proteínas F-Box/genética , Genoma de Planta
4.
Purinergic Signal ; 16(1): 85-96, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32043211

RESUMO

The improvement of cryopreserved oocyte survival is imperative for the preservation of female fertility. In this study, we investigate whether P2Y2 receptors (P2Y2R) can be directly implicated in calcium (Ca2+) homeostasis misbalances observed during the cryopreservation process of cumulus oocyte complexes (COC). Firstly, RNA was extracted from bovine immature and mature oocytes and cumulus cells and real-time PCR performed to identify P2Y2R transcripts (experiment 1). Changes in intracellular calcium concentration [Ca2+]i of mature COC and oocytes (experiment 2) were measured upon exposure to cryoprotectants (CPA), UTP (P2Y2R stimulator, 100 µM), and/or suramin (P2Y2R inhibitor, 100 and 300 µM). The functional role of P2Y2R was investigated by analyzing the effect on oocyte viability of its modulation prior and during oocyte exposure to CPA (experiment 3). Mature COC were randomly divided into groups, and exposed to CPA and different P2Y2 modulators. Oocytes' viability, cortical granules location, and competence for development were assessed. Results showed that P2Y2R mRNAs are expressed in both oocytes and cumulus cells. Stimulation with UTP and CPA led to [Ca2+]i increase, and this effect was totally or partially blocked by suramin (P2Y2R inhibitor). Oocyte exposure to CPA and UTP reduced embryo rates compared with control and suramin100µM (P ≤ 0.04). The observed enhanced premature zona hardening in oocytes exposed to CPA (P = 0.04) and UTP (P = 0.005) stimulus was inhibited by suramin 100 µM. In conclusion, inhibition of P2Y2R during cryoprotectant exposure reduces premature intracellular Ca2+ release and significantly improves the developmental competence of exposed bovine oocytes.


Assuntos
Cálcio/metabolismo , Crioprotetores/toxicidade , Células do Cúmulo/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Receptores Purinérgicos P2Y2/metabolismo , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Células do Cúmulo/metabolismo , Feminino , Oócitos/efeitos dos fármacos , Oócitos/metabolismo
5.
Plant Biol (Stuttg) ; 20(5): 870-878, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29762883

RESUMO

Despite the great diversity of plant growth-promoting bacteria (PGPB) with potential to partially replace the use of N fertilisers in agriculture, few PGPB have been explored for the production of commercial inoculants, reinforcing the importance of identifying positive plant-bacteria interactions. Aiming to better understand the influence of PGPB inoculation in plant development, two PGPB species with distant phylogenetic relationship were inoculated in maize. Maize seeds were inoculated with Bacillus sp. or Azospirillum brasilense. After germination, the plants were subjected to two N treatments: full (N+) and limiting (N-) N supply. Then, anatomical, biometric and physiological analyses were performed. Both PGPB species modified the anatomical pattern of roots, as verified by the higher metaxylem vessel element (MVE) number. Bacillus sp. also increased the MVE area in maize roots. Under N+ conditions, both PGPB decreased leaf protein content and led to development of shorter roots; however, Bacillus sp. increased root and shoot dry weight, whereas A. brasilense increased photosynthesis rate and leaf nitrate content. In plants subjected to N limitation (N-), photosynthesis rate and photosystem II efficiency increased in maize inoculated with Bacillus sp., whilst A. brasilense contained higher ammonium, amino acids and total soluble sugars in leaves, compared to the control. Plant developmental and metabolical patterns were switched by the inoculation, regardless of the inoculant bacterium used, producing similar as well as distinct modifications to the parameters studied. These results indicate that even non-diazotrophic inoculant strains can improve the plant N status as result of the morpho-anatomical and physiological modifications produced by the PGPB.


Assuntos
Azospirillum brasilense/metabolismo , Bacillus/metabolismo , Nitrogênio/farmacologia , Raízes de Plantas/anatomia & histologia , Zea mays/microbiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Zea mays/fisiologia
6.
Theriogenology ; 115: 124-132, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29754043

RESUMO

An essential role of prion protein testis specific (PRNT) and prion protein 2 dublet (PRND) genes in the male reproductive function has been highlighted, although a deeper knowledge for the mechanisms involved is still lacking. Our goal was to determine the importance of the PRNT haplotypic variants and mRNA expression levels in ovine spermatozoa freezability and ability for fertilization and embryo developmental processes. Their association with the PRND gene polymorphisms was also analyzed. DNA from rams belonging to three Portuguese sheep breeds (n = 28) was screened by single-strand conformation polymorphism (SSCP) analysis to identify the PRNT and PRND polymorphisms. Semen collected from these rams was cryopreserved and fertility traits evaluated. The SSCP analyses revealed polymorphisms in the codons 6, 38, 43 and 48 of the PRNT coding region - respectively c.17C > T (p.Ser6Phe, which disrupts a consensus arginine-X-X serine/threonine motif); c.112G > C (p.Gly38 > Arg); and synonymous c.129T > C and c.144A > G. The polymorphisms in codons 6, 38 and 48 occur simultaneously while the one in codon 43 occurs independently. Six haplotypes were identified in the PRNT coding region, resulting in three different amino acid polymorphic variants (6S-38G-43C-48V, S6F-G38R-43C-48V and 6F-38R-43C-48V). The PRNT gene mRNA transcript level in spermatozoa was related to the identified haplotypic variants, either considering the codons 6-38-48 (P ≤ 0.0001) or the codon 43 alone (P ≤ 0.0001) or altogether (P ≤ 0.0001). An interaction between PRNT haplotypes and PRND genotypes on PRNT transcript level was also identified (P = 0.0003). Rams carrying the 17C-112G-144A PRNT haplotype had sperm with the highest post-thawed individual motility (P ≤ 0.03). Combined PRNT and PRND polymorphic variation influenced the post-thawed individual motility (P = 0.01). The male PRNT haplotypic, either considering the codons 6-38-48 and 43 altogether or the codon 43 alone, interfered (P ≤ 0.04) in embryo production rates. In conclusion, our data confirm that the PRNT gene is highly polymorphic in sheep and that the PRNT and PRND genotypes are associated. The identified polymorphisms of PRNT coding region seems to interfere on the ram spermatozoa mRNA transcript level and on male fertility, specifically in sperm freezability and ability for embryo development.


Assuntos
Polimorfismo Conformacional de Fita Simples/genética , Proteínas Priônicas/genética , RNA Mensageiro/análise , Carneiro Doméstico/genética , Espermatozoides/química , Espermatozoides/fisiologia , Animais , Códon/genética , Criopreservação/veterinária , Fertilidade/genética , Fertilização in vitro/veterinária , Genótipo , Haplótipos , Masculino , Príons/genética , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Testículo/química
7.
J Neonatal Perinatal Med ; 11(1): 37-43, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29689737

RESUMO

BACKGROUND: Congenital diaphragmatic hernia (CDH) has a high mortality rate, representing a therapeutic challenge. Prenatal diagnosis (PND) is essential in defining optimal perinatal strategy, particularly delivery planning. Hospital Pediátrico de Coimbra is the referral centre for all neonatal surgery, particularly CDH, for the central region of Portugal. The aim was to evaluate clinical management and outcome of newborns with CDH. METHODS: An exploratory retrospective study made up of newborns admitted to PICU with CDH was undertaken between January 1995 and December 2014. Two groups were formed based on their year of admission: group A (1995- 2004) and group B (2005- 2014) and were compared. RESULTS: The mean birth weight of the 69 newborns admitted was 2.762 ± 696 g; the median of the gestational age was 38 weeks. Associated malformations were observed in 28 (40.5%) and 15 (21.7%) had a right-sided diaphragm defect. The global mortality was 13.0%; in group A was significantly higher than in group B (22.2 vs 3.0%; p = 0.029). A reduction in mortality throughout the years was confirmed after adjusting for POS score (OR = 0.77; 95% CI: 0.62- 0.96, p = 0.021). PND was made in 30.6% of cases in the group A and 66.7% in the group B (p = 0.03). Tertiary perinatal hospital birth was achieved in 60% of newborns in the group A versus 84.8% in group B (p = 0.022). Maximum fraction of inspired oxygen showed a statistically significant difference between the two study groups (60% vs 40%; p = 0.009). CONCLUSIONS: A significant decrease in mortality was observed throughout the study. The authors highlight the increase in prenatal diagnosis and an improvement in perinatal care with planning delivery as important contributors to these results.


Assuntos
Peso ao Nascer , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/terapia , Respiração Artificial , Oxigenação por Membrana Extracorpórea , Feminino , Idade Gestacional , Hérnias Diafragmáticas Congênitas/fisiopatologia , Herniorrafia , Humanos , Hipnóticos e Sedativos/uso terapêutico , Imobilização , Recém-Nascido , Intubação Intratraqueal , Masculino , Estudos Retrospectivos , Taxa de Sobrevida , Centros de Atenção Terciária , Resultado do Tratamento , Ultrassonografia Pré-Natal
8.
Plant Biol (Stuttg) ; 19(5): 720-727, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28637094

RESUMO

The re-composition of deforested environments requires the prior acclimation of seedlings to full sun in nurseries. Seedlings can overcome excess light either through the acclimation of pre-existing fully expanded leaves or through the development of new leaves that are acclimated to the new light environment. Here, we compared the acclimation capacity of mature (MatL, fully expanded at the time of transfer) and newly expanded (NewL, expanded after the light shift) leaves of Guazuma ulmifolia Lam. (Malvaceae) seedlings to high light. The seedlings were initially grown under shade and then transferred to full sunlight. MatL and NewL were used for chlorophyll fluorescence and gas exchange analyses, pigment extraction and morpho-anatomical measurements. After the transfer of seedlings to full sun, the MatL persisted and acclimated to some extent to the new light condition, since they underwent alterations in some morpho-physiological traits and maintained a functional electron transport chain and positive net photosynthesis rate. However, long-term exposure to high light led to chronic photoinhibition in MatL, which could be related to the limited plasticity of leaf morpho-anatomical attributes. However, the NewL showed a high capacity to use the absorbed energy in photochemistry and dissipate excess energy harmlessly, attributes that were favoured by the high structural plasticity exhibited by these leaves. Both the maintenance of mature, photosynthetically active leaves and the production of new leaves with a high capacity to cope with excess energy were important for acclimation of G. ulmifolia seedlings.


Assuntos
Aclimatação/fisiologia , Luz , Malvaceae/crescimento & desenvolvimento , Clorofila/metabolismo , Malvaceae/metabolismo , Malvaceae/efeitos da radiação , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Floresta Úmida
9.
Reprod Fertil Dev ; 29(5): 985-997, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28442049

RESUMO

The aim of the present study was to examine the role of Doppel protein in the capacitation process and fertilising ability of both fresh and frozen-thawed (FT) spermatozoa from rams carrying different prion protein 2 (dublet) (PRND) gene polymorphisms. The detection efficacy of new anti-Doppel monoclonal antibodies and PRND mRNA quantification were also explored in ovine spermatozoa. Three different genotypes (AA, GA, GG) were identified for codon 26 of ovine PRND-c.78G>A. Using flow cytometry, a higher fluorescence was detected in fresh compared with FT sperm samples incubated with anti-Doppel primary and fluorescein isothiocyanate-conjugated secondary antibodies (P<0.05). Capacitation was affected by semen treatment (fresh and FT) and male PRND genotype (P<0.05). After IVF, the use of fresh semen resulted in a higher cleavage rate than the use of FT spermatozoa (P=0.004). IVF using spermatozoa from individuals classified as carriers of the AA or GA PRND genotypes resulted in higher cleavage rates than seen using spermatozoa from GG carriers (P≤0.0006). Finally, using semen from rams with the AA PRND genotype resulted in the highest Day 6 and Day 8 embryo rates (P≤0.04). In conclusion, the results of the present study confirm that the identification of different PRND genotypes is important for studying the sperm capacitation process and for improving sperm cryoresistance and embryo production. Furthermore, the detection of Doppel in ejaculated ovine spermatozoa, along with its low expression after cryopreservation, strongly suggests an important physiological function of this protein in male fertility.


Assuntos
Fertilidade/genética , Proteínas Ligadas por GPI/genética , Príons/genética , Capacitação Espermática/genética , Espermatozoides/metabolismo , Animais , Criopreservação , Proteínas Ligadas por GPI/metabolismo , Genótipo , Masculino , Príons/metabolismo , Preservação do Sêmen/métodos , Ovinos , Motilidade dos Espermatozoides/fisiologia
12.
Anim Genet ; 47(1): 128-32, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26538093

RESUMO

The objective of this study was to search for polymorphisms in the ovine prion-related protein (testis-specific) gene (PRNT). Sampling included 567 sheep from eight Portuguese breeds. The PRNT gene-coding region was analyzed by single-strand conformation polymorphism and sequencing, allowing the identification of the first ovine PRNT polymorphisms, in codons 6, 38, 43 and 48: c.17C>T (p.Ser6Phe, which disrupts a consensus arginine-X-X-serine/threonine motif); c.112G>C (p.Gly38>Arg); c.129T>C and c.144A>G (synonymous) respectively. Polymorphisms in codons 6, 38 and 48 occur simultaneously in 50.6% of the animals, 38.8% presenting as heterozygous. To study the distribution of the polymorphism in codon 43, a restriction fragment length polymorphism analysis was performed. Polymorphic variant c.129C, identified in 89.8% of the animals with 32.8% presented as heterozygous, was considered the wild genotype in Portuguese sheep. Eight different haplotypes which have comparable distribution in all breeds were identified for the PRNT gene. In conclusion, the PRNT coding region is highly polymorphic in sheep, unlike the prion protein 2 dublet gene (PRND), in which we previously found only one synonymous substitution (c.78G>A), in codon 26. The absence or reduced number of PRND heterozygotes (c.78G>A) was significantly associated with three PRNT haplotypes (17C-112G-129T-144A,17CT-112GC-129CT-144AG and 17T-112C-129C-144G), and the only three animals found homozygous at c.78A had the 17C-112G-129C-144A PRNT haplotype. These results constitute evidence of an association between polymorphic variation in PRND and PRNT genes, as has already been observed for PRND and prion protein gene (PRNP).


Assuntos
Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Príons/genética , Carneiro Doméstico/genética , Animais , Cruzamento , Feminino , Frequência do Gene , Genótipo , Haplótipos , Masculino , Portugal , Análise de Sequência de DNA
13.
Braz J Biol ; 75(4 Suppl 1): S206-14, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26602353

RESUMO

We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23° 27'S and 51° 15'W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.


Assuntos
Ficus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Brasil , Florestas , Folhas de Planta/crescimento & desenvolvimento , Reprodução , Estações do Ano , Especificidade da Espécie
14.
Braz. j. biol ; 75(4)Nov. 2015.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468341

RESUMO

Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27S and 51°15W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.


Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27S e 51°15W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.

15.
Braz. j. biol ; 75(4,supl.1): 206-214, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768222

RESUMO

Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27’S and 51°15’W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.


Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27’S e 51°15’W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.


Assuntos
Ficus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Brasil , Florestas , Folhas de Planta/crescimento & desenvolvimento , Reprodução , Estações do Ano , Especificidade da Espécie
16.
Reprod Domest Anim ; 47(2): 196-202, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21806689

RESUMO

The function of prion-like protein Doppel was suggested to be related to male fertility. In this study, the importance of ovine Doppel polypeptide on spermatozoa capacitation and fertilization was evaluated. After refolding, recombinant Doppel (rDpl) was supplemented with different concentrations (40, 80 or 190 ng/ml) to ovine spermatozoa during the capacitation process. In experiment 1, post-thawed ovine spermatozoa were incubated with different concentrations of rDpl during 1 h for swim-up, and changes in sperm motility, concentration, vigour, viability and capacitation were monitored (10 replicates). In experiment 2, the fertilization ability of post-swim-up spermatozoa incubated as above was tested through heterologous fertilization of bovine in vitro matured oocytes (n = 423, three replicates). Regardless of dosage, rDpl improved (p ≤ 0.03) spermatozoa viability. Sperm individual motility and vigour were the highest (p ≤ 0.04) for the group receiving 190 ng/ml rDpl. Sperm supplemented with the highest doses of rDpl achieved higher (p = 0.02) fertilization rates (56.0 ± 3.0%) than control (39.1 ± 2.2%) and 40 ng/ml rDpl (39.8 ± 2.7%). Preliminary data suggest that Doppel protein may enhance in vitro spermatozoa fertilizing ability.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Príons/metabolismo , Carneiro Doméstico/fisiologia , Espermatozoides/fisiologia , Animais , Clonagem Molecular , Fertilização in vitro/veterinária , Proteínas Ligadas por GPI/genética , Regulação da Expressão Gênica/fisiologia , Masculino , Príons/genética , Capacitação Espermática/fisiologia , Motilidade dos Espermatozoides/fisiologia
17.
Genet Mol Res ; 10(2): 1180-7, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21732282

RESUMO

Studies on intraspecific variation can contribute to the development of conservation strategies by identifying units of conservation for threatened species. Aspidosperma polyneuron is a tropical tree of seasonal semideciduous forests that is currently endangered and protected because it has been heavily logged for lumber, although it was once common in Brazil and neighboring countries. We investigated genetic structure in two samples of A. polyneuron collected from steep hillsides and from flat areas of a natural forest fragment in northern Paraná State, Brazil. Seven AFLP primer combinations yielded 200 markers, with a polymorphic rate of 88.5% for samples from the flat area and 99% for samples from the high declivity area. Total genetic diversity (H(T)) was 0.387, while the genetic diversity within the populations (H(S)) was 0.307 and 0.372, for samples from the flat and the high declivity areas, respectively. Genetic differentiation between samples was high, with a mean F(ST) of 0.265 and a genetic distance of 0.148, indicative of a high degree of genetic structure over a short distance. Principal coordinate analysis separated the samples into three groups of individuals; the first group included individuals from the high declivity area, the second group consisted of individuals only from the flat area, and the third group had individuals from both areas. Bayesian analysis also showed K = 3 clusters. The unexpected high level of intraspecific variation of A. polyneuron in this small forest fragment should be taken into account when evaluating the genetic impact of forest degradation on this species in other semideciduous forest fragments.


Assuntos
Aspidosperma/genética , Marcadores Genéticos , Variação Genética , Geografia , Brasil
18.
Genet Mol Res ; 10(1): 526-36, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21476198

RESUMO

Knowledge of the effects of flooding on plant survival is relevant for the efficiency of management and conservation programs. Schinus terebinthifolius is a tree of economic and ecological importance that is common in northeast Brazil. Flooding tolerance and genetic variation were investigated in two riparian populations of S. terebinthifolius distributed along two different ecological regions of the Tibagi River basin. Flooding tolerance was evaluated through the investigation of young plants, submitted to different flooding intensities to examine the morphological and anatomical responses to this stress. The growth rate of S. terebinthifolius was not affected by flooding, but total submersion proved to be lethal for 100% of the plants. Morphological alterations such as hypertrophied lenticels were observed in both populations and lenticel openings were significantly higher in plants from one population. Genetic analysis using DNA samples obtained from both populations showed a moderate degree of genetic variation between populations (13.7%); most of the variation was found within populations (86.3%). These results show that for conservation purposes and management of degraded areas, both populations should be preserved and could be used in programs that intend to recompose riparian forests.


Assuntos
Anacardiaceae/genética , Variação Genética , Genética Populacional , Anacardiaceae/anatomia & histologia , Anacardiaceae/crescimento & desenvolvimento , Brasil , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Rios
19.
J Viral Hepat ; 18(1): 1-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20796208

RESUMO

Thrombocytopenia (TCP) is a haematological condition known to occur in chronically infected hepatitis C (HCV) patients and may interfere with diagnostic procedures, such as liver biopsy, because of risk of bleeding. It may also exclude patients from effective antiviral treatment. We conducted a systematic literature review of articles and conference abstracts, to assess the prevalence of TCP among those with HCV and to describe demographics, liver disease stage and treatment characteristics of these patients. Studies of individuals with confirmed chronic HCV infection were included in the review if the study had a clear definition of thrombocytopenia and a sample size of at least 50 subjects. The final selection included 27 studies (21 articles and six abstracts). The definitions of thrombocytopenia varied between studies and were based either on platelet counts, with threshold levels ranging between ≤ 100 × 10(9) and ≤ 180 × 10(9) /L, or on criteria set in haematological guidelines. The prevalence of TCP ranged from 0.16% to 45.4% and more than half of the studies reported a TCP prevalence of 24% or more. Because of the different TCP definitions, heterogeneity in study design and insufficient data on study characteristics such as age, gender, HCV treatment rates and disease severity an overall summary estimate of TCP prevalence among patients with HCV was not feasible. However, the relatively large prevalence in the majority of the studies suggests that there may be a substantial number of HCV patients at risk of bleeding complications and reduced likelihood of successful HCV antiviral treatment.


Assuntos
Hepatite C Crônica/complicações , Hepatite C Crônica/epidemiologia , Trombocitopenia/complicações , Trombocitopenia/epidemiologia , Antivirais/uso terapêutico , Feminino , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/epidemiologia , Masculino , Prevalência
20.
Genet Mol Res ; 9(4): 1946-56, 2010 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-20927713

RESUMO

Soybean genotypes MG/BR46 (Conquista) and BR16, drought-tolerant and -sensitive, respectively, were compared in terms of morphophysiological and gene-expression responses to water stress during two stages of development. Gene-expression analysis showed differential responses in Gmdreb1a and Gmpip1b mRNA expression within 30 days of water-deficit initiation in MG/BR46 (Conquista) plants. Within 45 days of initiating stress, Gmp5cs and Gmpip1b had relatively higher expression. Initially, BR16 showed increased expression only for Gmdreb1a, and later (45 days) for Gmp5cs, Gmdefensin and Gmpip1b. Only BR16 presented down-regulated expression of genes, such as Gmp5cs and Gmpip1b, 30 days after the onset of moisture stress, and Gmgols after 45 days of stress. The faster perception of water stress in MG/BR46 (Conquista) and the better maintenance of up-regulated gene expression than in the sensitive BR16 genotype imply mechanisms by which the former is better adapted to tolerate moisture deficiency.


Assuntos
Secas , Expressão Gênica , Genes de Plantas , Glycine max/fisiologia , RNA Mensageiro/genética , Glycine max/genética , Estresse Fisiológico
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