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1.
Glob Chang Biol ; 30(8): e17440, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39185562

RESUMO

The use of plant genetic resources (PGR)-wild relatives, landraces, and isolated breeding gene pools-has had substantial impacts on wheat breeding for resistance to biotic and abiotic stresses, while increasing nutritional value, end-use quality, and grain yield. In the Global South, post-Green Revolution genetic yield gains are generally achieved with minimal additional inputs. As a result, production has increased, and millions of hectares of natural ecosystems have been spared. Without PGR-derived disease resistance, fungicide use would have easily doubled, massively increasing selection pressure for fungicide resistance. It is estimated that in wheat, a billion liters of fungicide application have been avoided just since 2000. This review presents examples of successful use of PGR including the relentless battle against wheat rust epidemics/pandemics, defending against diseases that jump species barriers like blast, biofortification giving nutrient-dense varieties and the use of novel genetic variation for improving polygenic traits like climate resilience. Crop breeding genepools urgently need to be diversified to increase yields across a range of environments (>200 Mha globally), under less predictable weather and biotic stress pressure, while increasing input use efficiency. Given that the ~0.8 m PGR in wheat collections worldwide are relatively untapped and massive impacts of the tiny fraction studied, larger scale screenings and introgression promise solutions to emerging challenges, facilitated by advanced phenomic and genomic tools. The first translocations in wheat to modify rhizosphere microbiome interaction (reducing biological nitrification, reducing greenhouse gases, and increasing nitrogen use efficiency) is a landmark proof of concept. Phenomics and next-generation sequencing have already elucidated exotic haplotypes associated with biotic and complex abiotic traits now mainstreamed in breeding. Big data from decades of global yield trials can elucidate the benefits of PGR across environments. This kind of impact cannot be achieved without widescale sharing of germplasm and other breeding technologies through networks and public-private partnerships in a pre-competitive space.


Assuntos
Segurança Alimentar , Melhoramento Vegetal , Doenças das Plantas , Triticum , Triticum/genética , Triticum/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Resistência à Doença/genética , Pandemias , Fungicidas Industriais , Meio Ambiente
2.
Plant Biotechnol J ; 21(3): 482-496, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35598169

RESUMO

Wheat is a globally vital crop, but its limited genetic variation creates a challenge for breeders aiming to maintain or accelerate agricultural improvements over time. Introducing novel genes and alleles from wheat's wild relatives into the wheat breeding pool via introgression lines is an important component of overcoming this low variation but is constrained by poor genomic resolution and limited understanding of the genomic impact of introgression breeding programmes. By sequencing 17 hexaploid wheat/Ambylopyrum muticum introgression lines and the parent lines, we have precisely pinpointed the borders of introgressed segments, most of which occur within genes. We report a genome assembly and annotation of Am. muticum that has facilitated the identification of Am. muticum resistance genes commonly introgressed in lines resistant to stripe rust. Our analysis has identified an abundance of structural disruption and homoeologous pairing across the introgression lines, likely caused by the suppressed Ph1 locus. mRNAseq analysis of six of these introgression lines revealed that novel introgressed genes are rarely expressed and those that directly replace a wheat orthologue have a tendency towards downregulation, with no discernible compensation in the expression of homoeologous copies. This study explores the genomic impact of introgression breeding and provides a schematic that can be followed to characterize introgression lines and identify segments and candidate genes underlying the phenotype. This will facilitate more effective utilization of introgression pre-breeding material in wheat breeding programmes.


Assuntos
Poaceae , Transcriptoma , Triticum , Alelos , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética , Poaceae/genética
3.
Mol Ecol ; 32(4): 892-903, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36435981

RESUMO

Ceruminous gland tumours are highly prevalent in the ear canals of Santa Catalina Island foxes (Urocyon littoralis catalinae). Previous work suggests that tumours may result from a combination of ectoparasites, disruption of the host-associated microbiome, and host immunopathology. More specifically, ear mite infection has been associated with broad-scale microbial dysbiosis marked by secondary bacterial infection with the opportunistic pathogen Staphylococcus pseudintermedius. Together, ear mites and S. pseudintermedius probably sustain chronic inflammation and promote conditions suitable for tumour development. In the present study, we expanded upon this framework by constructing otic microbial community networks for mite-infected and uninfected foxes sampled in 2017-2019. Across sampling years, we observed consistent signatures of microbial dysbiosis in mite-infected ear canals, including reduced microbial diversity and shifted abundance towards S. pseudintermedius. Network analysis further revealed that mite infection disrupts overall community structure. In mite-infected networks, interaction strengths between taxa were generally weaker, and numerous subnetworks disappeared altogether. We also found that two strains of S. pseudintermedius connected to the main network, suggesting that multistrain biofilm formation may be occurring. In contrast, S. pseudintermedius is peripheral in the uninfected network, with its only connections including a second strain of S. pseudintermedius and the possible competitor Acinetobacter rhizosphaerae. Finally, the lineup of potential keystone taxa shifted across disease states. Fusobacteria spp., a carcinogenesis-promoting microbe, assumed a keystone role in the mite-infected community. Considered together, these findings provide insights into how mite infection may destabilize the microbiome and ultimately contribute to tumour development in this island endemic species.


Assuntos
Microbiota , Ácaros , Animais , Raposas , Disbiose , Consórcios Microbianos
4.
J Clin Microbiol ; 59(1)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33087440

RESUMO

COVID-19-associated pulmonary aspergillosis (CAPA) was recently reported as a potential infective complication affecting critically ill patients with acute respiratory distress syndrome following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, with incidence rates varying from 8 to 33% depending on the study. However, definitive diagnosis of CAPA is challenging. Standardized diagnostic algorithms and definitions are lacking, clinicians are reticent to perform aerosol-generating bronchoalveolar lavages for galactomannan testing and microscopic and cultural examination, and questions surround the diagnostic sensitivity of different serum biomarkers. Between 11 March and 14 July 2020, the UK National Mycology Reference Laboratory received 1,267 serum and respiratory samples from 719 critically ill UK patients with COVID-19 and suspected pulmonary aspergillosis. The laboratory also received 46 isolates of Aspergillus fumigatus from COVID-19 patients (including three that exhibited environmental triazole resistance). Diagnostic tests performed included 1,000 (1-3)-ß-d-glucan and 516 galactomannan tests on serum samples. The results of this extensive testing are presented here. For a subset of 61 patients, respiratory specimens (bronchoalveolar lavage specimens, tracheal aspirates, and sputum samples) in addition to serum samples were submitted and subjected to galactomannan testing, Aspergillus-specific PCR, and microscopy and culture. The incidence of probable/proven and possible CAPA in this subset of patients was approximately 5% and 15%, respectively. Overall, our results highlight the challenges in biomarker-driven diagnosis of CAPA, especially when only limited clinical samples are available for testing, and the importance of a multimodal diagnostic approach involving regular and repeat testing of both serum and respiratory samples.


Assuntos
Antígenos de Fungos/sangue , Aspergillus fumigatus/isolamento & purificação , Aspergilose Pulmonar Invasiva/diagnóstico , Aspergilose Pulmonar Invasiva/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aspergillus fumigatus/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/microbiologia , COVID-19/etiologia , Estado Terminal , Feminino , Galactose/análogos & derivados , Humanos , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Masculino , Mananas/sangue , Pessoa de Meia-Idade , Proteoglicanas , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2 , Reino Unido , beta-Glucanas/sangue
5.
Plant Biotechnol J ; 18(3): 743-755, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31465620

RESUMO

For future food security, it is important that wheat, one of the most widely consumed crops in the world, can survive the threat of abiotic and biotic stresses. New genetic variation is currently being introduced into wheat through introgressions from its wild relatives. For trait discovery, it is necessary that each introgression is homozygous and hence stable. Breeding programmes rely on efficient genotyping platforms for marker-assisted selection (MAS). Recently, single nucleotide polymorphism (SNP)-based markers have been made available on high-throughput Axiom® SNP genotyping arrays. However, these arrays are inflexible in their design and sample numbers, making their use unsuitable for long-term MAS. SNPs can potentially be converted into Kompetitive allele-specific PCR (KASP™) assays that are comparatively cost-effective and efficient for low-density genotyping of introgression lines. However, due to the polyploid nature of wheat, KASP assays for homoeologous SNPs can have difficulty in distinguishing between heterozygous and homozygous hybrid lines in a backcross population. To identify co-dominant SNPs, that can differentiate between heterozygotes and homozygotes, we PCR-amplified and sequenced genomic DNA from potential single-copy regions of the wheat genome and compared them to orthologous copies from different wild relatives. A panel of 620 chromosome-specific KASP assays have been developed that allow rapid detection of wild relative segments and provide information on their homozygosity and site of introgression in the wheat genome. A set of 90 chromosome-nonspecific assays was also produced that can be used for genotyping introgression lines. These multipurpose KASP assays represent a powerful tool for wheat breeders worldwide.


Assuntos
Mapeamento Cromossômico , Homozigoto , Melhoramento Vegetal , Triticum/genética , Cromossomos de Plantas/genética , Genótipo , Polimorfismo de Nucleotídeo Único
6.
New Phytol ; 228(6): 1767-1780, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32910841

RESUMO

The wild relatives of modern wheat represent an underutilized source of genetic and phenotypic diversity and are of interest in breeding owing to their wide adaptation to diverse environments. Leaf photosynthetic traits underpin the rate of production of biomass and yield and have not been systematically explored in the wheat relatives. This paper identifies and quantifies the phenotypic variation in photosynthetic, stomatal, and morphological traits in up to 88 wheat wild relative accessions across five genera. Both steady-state measurements and dynamic responses to step changes in light intensity are assessed. A 2.3-fold variation for flag leaf light and CO2 -saturated rates of photosynthesis Amax was observed. Many accessions showing higher and more variable Amax , maximum rates of carboxylation, electron transport, and Rubisco activity when compared with modern genotypes. Variation in dynamic traits was also significant; with distinct genus-specific trends in rates of induction of nonphotochemical quenching and rate of stomatal opening. We conclude that utilization of wild relatives for improvement of photosynthesis is supported by the existence of a high degree of natural variation in key traits and should consider not only genus-level properties but variation between individual accessions.


Assuntos
Melhoramento Vegetal , Triticum , Transporte de Elétrons , Fotossíntese , Folhas de Planta/genética , Triticum/genética
7.
Mol Ecol ; 29(8): 1463-1475, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31821650

RESUMO

The host-associated microbiome is increasingly recognized as a critical player in health and immunity. Recent studies have shown that disruption of commensal microbial communities can contribute to disease pathogenesis and severity. Santa Catalina Island foxes (Urocyon littoralis catalinae) present a compelling system in which to examine microbial dynamics in wildlife due to their depauperate genomic structure and extremely high prevalence of ceruminous gland tumors. Although the precise cause is yet unknown, infection with ear mites (Otodectes cynotis) has been linked to chronic inflammation, which is associated with abnormal cell growth and tumor development. Given the paucity of genomic variation in these foxes, other dimensions of molecular diversity, such as commensal microbes, may be critical to host response and disease pathology. We characterized the host-associated microbiome across six body sites of Santa Catalina Island foxes, and performed differential abundance testing between healthy and mite-infected ear canals. We found that mite infection was significantly associated with reduced microbial diversity and evenness, with the opportunistic pathogen Staphylococcus pseudintermedius dominating the ear canal community. These results suggest that secondary bacterial infection may contribute to the sustained inflammation associated with tumor development. As the emergence of antibiotic resistant strains remains a concern of the medical, veterinary, and conservation communities, uncovering high relative abundance of S. pseudintermedius provides critical insight into the pathogenesis of this complex system. Through use of culture-independent sequencing techniques, this study contributes to the broader effort of applying a more inclusive understanding of molecular diversity to questions within wildlife disease ecology.


Assuntos
Microbiota , Ácaros , Animais , Raposas , Microbiota/genética , Staphylococcus
8.
Theor Appl Genet ; 133(7): 2213-2226, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32313991

RESUMO

KEY MESSAGE: One hundred and thirty four introgressions from Thinopyrum elongatum have been transferred into a wheat background and were characterised using 263 SNP markers. Species within the genus Thinopyrum have been shown to carry genetic variation for a very wide range of traits including biotic and abiotic stresses and quality. Research has shown that one of the species within this genus, Th. elongatum, has a close relationship with the genomes of wheat making it a highly suitable candidate to expand the gene pool of wheat. Homoeologous recombination, in the absence of the Ph1 gene, has been exploited to transfer an estimated 134 introgressions from Th. elongatum into a hexaploid wheat background. The introgressions were detected and characterised using 263 single nucleotide polymorphism markers from a 35 K Axiom® Wheat-Relative Genotyping Array, spread across seven linkage groups and validated using genomic in situ hybridisation. The genetic map had a total length of 187.8 cM and the average chromosome length was 26.8 cM. Comparative analyses of the genetic map of Th. elongatum and the physical map of hexaploid wheat confirmed previous work that indicated good synteny at the macro-level, although Th. elongatum does not contain the 4A/5A/7B translocation found in wheat.


Assuntos
Pool Gênico , Genoma de Planta , Ploidias , Polimorfismo de Nucleotídeo Único , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Ligação Genética , Marcadores Genéticos , Genótipo , Fenótipo , Mapeamento Físico do Cromossomo , Poaceae/genética , Sintenia
9.
J Intellect Disabil ; 24(2): 194-211, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29929418

RESUMO

BACKGROUND: Psychotropic medication is widely prescribed to treat mental illness. However, it is controversial when used as a chemical restraint (CR) to manage challenging behaviours (CBs) of adults with intellectual disability (ID). CR has potentially negative consequences and affects human rights. METHOD: Qualitative research conducted between 2014 and 2015 explored the views of 'guardian' decision makers appointed under unique Queensland legislation oversighting the use of CR. RESULTS: Findings included (1) negative conceptualization of CR, (2) concerning relationships with prescribers and disability sector staff, (3) challenges to information seeking about people with ID prescribed CR and (4) problematic implementation of positive behaviour support plans. CONCLUSION: According to guardians, CR may be used in lieu of community supports, and prescribers sometimes diagnose mental illness to avoid CR legislative requirements. Guardians, prescribers and professionals would benefit from training that addresses the intersection between physical and mental health, CB and CR.


Assuntos
Deficiência Intelectual/tratamento farmacológico , Tutores Legais/legislação & jurisprudência , Pessoas com Deficiência Mental/legislação & jurisprudência , Comportamento Problema , Psicotrópicos/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Queensland
10.
BMC Plant Biol ; 19(1): 183, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060503

RESUMO

BACKGROUND: Triticum timopheevii (2n = 4x = 28; AtAtGG), is an important source for new genetic variation for wheat improvement with genes for potential disease resistance and salt tolerance. By generating a range of interspecific hybrid lines, T. timopheevii can contribute to wheat's narrow gene-pool and be practically utilised in wheat breeding programmes. Previous studies that have generated such introgression lines between wheat and its wild relatives have been unable to use high-throughput methods to detect the presence of wild relative segments in such lines. RESULTS: A whole genome introgression approach, exploiting homoeologous recombination in the absence of the Ph1 locus, has resulted in the transfer of different chromosome segments from both the At and G genomes of T. timopheevii into wheat. These introgressions have been detected and characterised using single nucleotide polymorphism (SNP) markers present on a high-throughput Axiom® Genotyping Array. The analysis of these interspecific hybrid lines has resulted in the detection of 276 putative unique introgressions from T. timopheevii, thereby allowing the generation of a genetic map of T. timopheevii containing 1582 SNP markers, spread across 14 linkage groups representing each of the seven chromosomes of the At and G genomes of T. timopheevii. The genotyping of the hybrid lines was validated through fluorescence in situ hybridisation (FISH). Comparative analysis of the genetic map of T. timopheevii and the physical map of the hexaploid wheat genome showed that synteny between the two species is highly conserved at the macro-level and confirmed the presence of inter- and intra-genomic translocations within the At and G genomes of T. timopheevii that have been previously only detected through cytological techniques. CONCLUSIONS: In this work, we report a set of SNP markers present on a high-throughput genotyping array, able to detect the presence of T. timopheevii in a hexaploid wheat background making it a potentially valuable tool for marker assisted selection (MAS) in wheat pre-breeding programs. These valuable resources of high-density molecular markers and wheat-T. timopheevii hybrid lines will greatly enhance the work being undertaken for wheat improvement through wild relative introgressions.


Assuntos
Genoma de Planta , Hibridização Genética , Poliploidia , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Ecótipo , Ligação Genética , Loci Gênicos , Marcadores Genéticos , Genótipo , Polimorfismo de Nucleotídeo Único/genética , Recombinação Genética/genética , Sementes/genética , Especificidade da Espécie
11.
Theor Appl Genet ; 132(5): 1555-1570, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30767030

RESUMO

KEY MESSAGE: Cytogenetic analysis and array-based SNP genotyping of wheat- Th. intermedium introgression lines allowed identification of 634 chromosome-specific SNP markers across all twenty-one chromosomes of Th. intermedium (StJ r J vs , 2 n = 6 x = 42). Thinopyrum intermedium (2n = 6x = 42, StJrJvs) is one of the most promising reservoirs of useful genes including tolerance to abiotic stresses, perenniality and disease resistance not available in the cultivated bread wheat. The transfer of genetic diversity from wild species to wheat offers valuable responses to the effects of climate change. The new array-based single-nucleotide polymorphism (SNP) marker technology provides cheap and easy-to-use molecular markers for marker-assisted selection (MAS) in wheat breeding programmes. Here, we focus on the generation of a new chromosome-specific SNP marker set that can be used to characterize and identify the Th. intermedium chromosomes or chromosome segments transferred into wheat. A progressive investigation of marker development was conducted using 187 various newly developed wheat-Th. intermedium introgression lines and the Axiom® Wheat-Relative Genotyping array. We employed molecular cytogenetic techniques to clarify the genome constitution of the Th. intermedium parental lines and validated 634 chromosome-specific SNPs. Our data confirmed the allohexaploid nature of Th. intermedium and demonstrated that the St genome-specific GISH signal and markers are present at the centromeric regions of chromosomes 1Jvs, 2Jvs, 3Jvs and 7Jvs. The SNP markers presented here will be introduced into current wheat improvement programmes, offering a significant speed-up in wheat breeding and making it possible to deal with the transfer of the full genetic potential of Th. intermedium into wheat.


Assuntos
Resistência à Doença/genética , Exoma , Polimorfismo de Nucleotídeo Único , Triticum/genética , Cruzamento , Cromossomos de Plantas , Marcadores Genéticos , Técnicas de Genotipagem , Sintenia
12.
J Exp Bot ; 69(8): 1861-1871, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29635481

RESUMO

Supernumerary 'B' chromosomes are non-essential components of the genome present in a range of plant and animal species-including many grasses. Within diploid and polyploid ryegrass and fescue species, including the forage grass perennial ryegrass (Lolium perenne L.), the presence of B chromosomes has been reported as influencing both chromosome pairing and chiasma frequencies. In this study, the effects of the presence/absence of B chromosomes on genetic recombination has been investigated through generating DArT (Diversity Arrays Technology) marker genetic maps for six perennial ryegrass diploid populations, the pollen parents of which contained either two B or zero B chromosomes. Through genetic and cytological analyses of these progeny and their parents, we have identified that, while overall cytological estimates of chiasma frequencies were significantly lower in pollen mother cells with two B chromosomes as compared with zero B chromosomes, the recombination frequencies within some marker intervals were actually increased, particularly for marker intervals in lower recombination regions of chromosomes, namely pericentromeric regions. Thus, in perennial ryegrass, the presence of two B chromosomes redistributed patterns of meiotic recombination in pollen mother cells in ways which could increase the range of allelic variation available to plant breeders.


Assuntos
Cromossomos de Plantas/genética , Lolium/genética , Recombinação Genética , Mapeamento Cromossômico , Pareamento Cromossômico , Diploide , Marcadores Genéticos , Lolium/citologia , Meiose , Pólen/citologia , Pólen/genética
13.
Theor Appl Genet ; 131(2): 389-406, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29101420

RESUMO

KEY MESSAGE: Genome-wide introgressions of Thinopyrum bessarabicum into wheat resulted in 12 recombinant lines. Cytological and molecular techniques allowed mapping of 1150 SNP markers across all seven chromosomes of the J genome. Thinopyrum bessarabicum (2n = 2x = 14, JJ) is an important source for new genetic variation for wheat improvement due to its salinity tolerance and disease resistance. Its practical utilisation in wheat improvement can be facilitated through development of genome-wide introgressions leading to a variety of different wheat-Th . bessarabicum translocation lines. In this study, we report the generation of 12 such wheat-Th . bessarabicum recombinant lines, through two different crossing strategies, which were characterized using sequential single colour and multi-colour genomic in situ hybridization (sc-GISH and mc-GISH), multi-colour fluorescent in situ hybridization (mc-FISH) and single nucleotide polymorphic (SNP) DNA markers. We also detected 13 lines containing different Th. bessarabicum chromosome aberrations through sc-GISH. Through a combination of molecular and cytological analysis of all the 25 lines containing Th. bessarabicum recombinants and chromosome aberrations we were able to physically map 1150 SNP markers onto seven Th. bessarabicum J chromosomes which were divided into 36 segmental blocks. Comparative analysis of the physical map of Th. bessarabicum and the wheat genome showed that synteny between the two species is highly conserved at the macro-level and confirmed that Th. bessarabicum contains the 4/5 translocation also present in the A genome of wheat. These wheat-Th . bessarabicum recombinant lines and SNP markers provide a useful genetic resource for wheat improvement with the latter having a wider impact as a tool for detection of introgressions from other Thinopyrum species containing the J or a closely-related genome such as Thinopyrum intermedium (JrJrJvsJvsStSt) and Thinopyrum elongatum (EeEe), respectively.


Assuntos
Cromossomos de Plantas/genética , Hibridização Genética , Poaceae/genética , Triticum/genética , Mapeamento Cromossômico , Marcadores Genéticos , Hibridização in Situ Fluorescente , Polimorfismo de Nucleotídeo Único , Sintenia , Translocação Genética
14.
Ann Bot ; 121(2): 229-240, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29216335

RESUMO

Background and Aims: Bread wheat (Triticum aestivum) has been through a severe genetic bottleneck as a result of its evolution and domestication. It is therefore essential that new sources of genetic variation are generated and utilized. This study aimed to generate genome-wide introgressed segments from Aegilops speltoides. Introgressions generated from this research will be made available for phenotypic analysis. Methods: Aegilops speltoides was crossed as the male parent to T. aestivum 'Paragon'. The interspecific hybrids were then backcrossed to Paragon. Introgressions were detected and characterized using the Affymetrix Axiom Array and genomic in situ hybridization (GISH). Key Results: Recombination in the gametes of the F1 hybrids was at a level where it was possible to generate a genetic linkage map of Ae. speltoides. This was used to identify 294 wheat/Ae. speltoides introgressions. Introgressions from all seven linkage groups of Ae. speltoides were found, including both large and small segments. Comparative analysis showed that overall macro-synteny is conserved between Ae. speltoides and T. aestivum, but that Ae. speltoides does not contain the 4A/5A/7B translocations present in wheat. Aegilops speltoides has been reported to carry gametocidal genes, i.e. genes that ensure their transmission through the gametes to the next generation. Transmission rates of the seven Ae. speltoides linkage groups introgressed into wheat varied. A 100 % transmission rate of linkage group 2 demonstrates the presence of the gametocidal genes on this chromosome. Conclusions: A high level of recombination occurs between the chromosomes of wheat and Ae. speltoides, leading to the generation of large numbers of introgressions with the potential for exploitation in breeding programmes. Due to the gametocidal genes, all germplasm developed will always contain a segment from Ae. speltoides linkage group 2S, in addition to an introgression from any other linkage group.


Assuntos
Aegilops/genética , Genes de Plantas/genética , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Citogenética , Genes de Plantas/fisiologia , Germinação/genética , Hibridização In Situ , Endogamia , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética , Recombinação Genética/genética , Sementes/genética , Sementes/fisiologia
15.
J Cancer Educ ; 33(3): 716-723, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-27796876

RESUMO

Cervical cancer is a significant public health issue, especially in the developing countries of sub-Saharan Africa. To examine knowledge adequacy on cervical cancer and screening test among African refugee and non-refugee women in Brisbane and further examine whether the level of knowledge vary between refugee and non-refugee women. A cross-sectional survey was conducted among 254 African-born women conveniently sampled from the Brisbane local government area. The outcome measures were knowledge on cervical cancer and Pap smear. In the multivariate logistic regression analysis non-refugees were more likely than refugees to have adequate knowledge about cervical cancer. Also, non-refugee women who were older and educated beyond secondary school, were more likely to have good knowledge about Pap smear test than refugee women. Overall, knowledge level about cervical cancer is limited among the participants and non-refugee women were more likely than refugee women to have good knowledge about cervical cancer and the screening test. These findings may inform the development of health education interventions for the targeted population to improve knowledge and awareness about cervical cancer and the screening guidelines in Australia.


Assuntos
População Negra/psicologia , Detecção Precoce de Câncer/psicologia , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Refugiados/psicologia , Neoplasias do Colo do Útero/prevenção & controle , Adulto , Idoso , Austrália/epidemiologia , População Negra/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou/psicologia , Teste de Papanicolaou/estatística & dados numéricos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Esfregaço Vaginal/psicologia , Esfregaço Vaginal/estatística & dados numéricos , Adulto Jovem
16.
Plant Biotechnol J ; 15(2): 217-226, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27459228

RESUMO

Despite some notable successes, only a fraction of the genetic variation available in wild relatives has been utilized to produce superior wheat varieties. This is as a direct result of the lack of availability of suitable high-throughput technologies to detect wheat/wild relative introgressions when they occur. Here, we report on the use of a new SNP array to detect wheat/wild relative introgressions in backcross progenies derived from interspecific hexaploid wheat/Ambylopyrum muticum F1 hybrids. The array enabled the detection and characterization of 218 genomewide wheat/Am. muticum introgressions, that is a significant step change in the generation and detection of introgressions compared to previous work in the field. Furthermore, the frequency of introgressions detected was sufficiently high to enable the construction of seven linkage groups of the Am. muticum genome, thus enabling the syntenic relationship between the wild relative and hexaploid wheat to be determined. The importance of the genetic variation from Am. muticum introduced into wheat for the development of superior varieties is discussed.


Assuntos
Variação Genética , Poaceae/genética , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Ligação Genética , Genoma de Planta , Genótipo , Técnicas de Genotipagem/métodos , Hibridização de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Sintenia
17.
J Neuropsychiatry Clin Neurosci ; 29(4): 375-382, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28449634

RESUMO

The assessment of functional neurological disorders (FND) requires an interdisciplinary approach. The authors retrospectively reviewed charts for 100 outpatients with FND and used univariate and regression analyses to investigate neuropsychiatric associations with gender, illness duration, and work disability; secondary analyses evaluated for differences across motor FND subtypes. Men reported higher rates of cognitive complaints and functional weakness, whereas women endorsed increased past physical/sexual trauma. Number of self-reported medication allergies/sensitivities positively correlated with illness duration. Individuals with functional weakness compared with other motor FND subtypes exhibited lower rates of past psychiatric hospitalization and head trauma. This study supports the feasibility of integrating FND research.


Assuntos
Transtorno Conversivo/epidemiologia , Adulto , Cognição , Comorbidade , Transtorno Conversivo/fisiopatologia , Transtorno Conversivo/terapia , Avaliação da Deficiência , Emprego , Feminino , Humanos , Entrevista Psicológica , Masculino , Massachusetts , Análise Multivariada , Doenças do Sistema Nervoso/epidemiologia , Doenças do Sistema Nervoso/fisiopatologia , Doenças do Sistema Nervoso/terapia , Pacientes Ambulatoriais , Análise de Regressão , Estudos Retrospectivos , Fatores Sexuais , Fatores de Tempo
18.
Health Promot J Austr ; 28(3): 217-224, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27802410

RESUMO

Issue addressed To compare the level of cervical screening uptake between refugee and non-refugee African immigrant women living in Brisbane, Australia, and examine factors associated with Pap smear testing. Methods Cross-sectional survey with a convenience sample of 254 women aged 21-62 years from 22 African countries (144 refugees, 110 non-refugees). Chi-square tests were used to compare the demographic and health-related characteristics between refugee and non-refugee women. Bivariate and multiple logistic regression analyses were used to assess the relationship between the outcome variable (Pap smear testing) and the independent variables. Results Two-thirds of women had used Pap smear services in Australia. Chi-square test analysis established that non-refugee women were significantly more likely to have used Pap smear services than refugee women (73.6% vs 61.8% respectively; P=0.047). Immigration status, however, was not a significant predictor of cervical screening uptake in the multiple regression analyses. The significant predictors for screening uptake in these analyses were work arrangement, parity, healthcare visit, knowledge about Pap smear and perceived susceptibility to cervical cancer. Conclusion Most women relied on opportunistic screening after receiving invitation letters to screen or after visiting health professionals for antenatal or postnatal care. So what? The findings suggest that organised cervical screening programs are not reaching most African immigrant women living in Brisbane. It is incumbent on the public health sector, including healthcare professionals and settlement agencies working with African communities, to develop health promotion strategies that meaningfully engage African immigrant women, including those from refugee backgrounds, to enhance their knowledge about cervical cancer and screening practices.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Refugiados , Neoplasias do Colo do Útero , Adulto , África/etnologia , Austrália , Estudos Transversais , Emigrantes e Imigrantes , Feminino , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Gravidez , Inquéritos e Questionários , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal , Adulto Jovem
19.
Plant Biotechnol J ; 14(5): 1195-206, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26466852

RESUMO

In wheat, a lack of genetic diversity between breeding lines has been recognized as a significant block to future yield increases. Species belonging to bread wheat's secondary and tertiary gene pools harbour a much greater level of genetic variability, and are an important source of genes to broaden its genetic base. Introgression of novel genes from progenitors and related species has been widely employed to improve the agronomic characteristics of hexaploid wheat, but this approach has been hampered by a lack of markers that can be used to track introduced chromosome segments. Here, we describe the identification of a large number of single nucleotide polymorphisms that can be used to genotype hexaploid wheat and to identify and track introgressions from a variety of sources. We have validated these markers using an ultra-high-density Axiom(®) genotyping array to characterize a range of diploid, tetraploid and hexaploid wheat accessions and wheat relatives. To facilitate the use of these, both the markers and the associated sequence and genotype information have been made available through an interactive web site.


Assuntos
Genoma de Planta/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único , Triticum/genética , Cruzamento , Pool Gênico , Marcadores Genéticos , Variação Genética , Genótipo , Técnicas de Genotipagem , Poliploidia
20.
Mol Ecol ; 25(10): 2176-94, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26992010

RESUMO

The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of six subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction-site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1-89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland grey foxes, and vice versa, indicating genetic drift drives genome-wide divergence. Nonetheless, outlier tests identified 3.6-6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness and reduced adaptive potential.


Assuntos
Evolução Molecular , Raposas/genética , Deriva Genética , Genética Populacional , Animais , California , Variação Genética , Técnicas de Genotipagem , Ilhas , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
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