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1.
Support Care Cancer ; 32(6): 397, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819504

RESUMO

PURPOSE: This study aimed to develop a patient-centered survivorship care plan (SCP) for US military Veteran bladder cancer (BC) survivors in accordance with the National Academy of Medicine recommendation that survivors receive an SCP at treatment completion. BC, which differentially impacts older men, is a costly and highly recurrent cancer associated with invasive procedures and long-term surveillance. Veteran BC survivors may face challenges navigating the patient-to-survivor transition due to their age and comorbidities. METHODS: We conducted 20 one-on-one qualitative interviews and 2 focus groups with Veteran BC survivors to understand their preferences for information and support to inform SCP development. Data were analyzed using rapid analysis. RESULTS: Participants voiced concerns about BC's impact on their psychosocial functioning and quality of life. They suggested information on BC recurrences, recommended surveillance schedules, long-term side effects and healthy living, and how and when to seek help if a medical problem arises should be included on the SCP to help manage expectations and access key resources during survivorship. Although participants had varying needs, many recommended including information on supportive resources (e.g., support groups, peer support programs) to manage cancer-related anxiety. Participants also suggested including Veteran-centered information (e.g., Veterans' BC risk factors). CONCLUSION: We developed an SCP to help Veteran BC survivors navigate the transition from patient to survivor. Adapting an SCP to address specific needs of the Veteran population was an important step in supporting Veteran BC survivors. Future research should evaluate the potential effectiveness of this SCP at improving Veterans' health outcomes and healthcare experiences.


Assuntos
Sobreviventes de Câncer , Grupos Focais , Assistência Centrada no Paciente , Pesquisa Qualitativa , Sobrevivência , Neoplasias da Bexiga Urinária , Veteranos , Humanos , Neoplasias da Bexiga Urinária/terapia , Neoplasias da Bexiga Urinária/psicologia , Masculino , Idoso , Sobreviventes de Câncer/psicologia , Pessoa de Meia-Idade , Assistência Centrada no Paciente/organização & administração , Veteranos/psicologia , Planejamento de Assistência ao Paciente/organização & administração , Feminino , Qualidade de Vida , Idoso de 80 Anos ou mais , Entrevistas como Assunto , Estados Unidos
2.
Clin Infect Dis ; 75(3): 382-389, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34849637

RESUMO

BACKGROUND: Urine cultures are nonspecific and often lead to misdiagnosis of urinary tract infection and unnecessary antibiotics. Diagnostic stewardship is a set of procedures that modifies test ordering, processing, and reporting in order to optimize diagnosis and downstream treatment. In this study, we aimed to develop expert guidance on best practices for urine culture diagnostic stewardship. METHODS: A RAND-modified Delphi approach with a multidisciplinary expert panel was used to ascertain diagnostic stewardship best practices. Clinical questions to guide recommendations were grouped into three thematic areas (ordering, processing, reporting) in practice settings of emergency department, inpatient, ambulatory, and long-term care. Fifteen experts ranked recommendations on a 9-point Likert scale. Recommendations on which the panel did not reach agreement were discussed during a virtual meeting, then a second round of ranking by email was completed. After secondary review of results and panel discussion, a series of guidance statements was developed. RESULTS: One hundred and sixty-five questions were reviewed. The panel reaching agreement on 104, leading to 18 overarching guidance statements. The following strategies were recommended to optimize ordering urine cultures: requiring documentation of symptoms, sending alerts to discourage ordering in the absence of symptoms, and cancelling repeat cultures. For urine culture processing, conditional urine cultures and urine white blood cell count as criteria were supported. For urine culture reporting, appropriate practices included nudges to discourage treatment under specific conditions and selective reporting of antibiotics to guide therapy decisions. CONCLUSIONS: These 18 guidance statements can optimize use of urine cultures for better patient outcomes.


Assuntos
Urinálise , Infecções Urinárias , Antibacterianos/uso terapêutico , Técnica Delphi , Humanos , Infecções Urinárias/diagnóstico
3.
J Urol ; 207(3): 534-540, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34694916

RESUMO

PURPOSE: The utility of blue light cystoscopy (BLC) in patients receiving bacillus Calmette-Guérin (BCG) during post-treatment cystoscopy is not well understood. Our objective was to determine if BLC improves recurrence detection in patients with non-muscle invasive bladder cancer (NMIBC) undergoing BCG. MATERIALS AND METHODS: Using the prospective multi-institutional Cysview® Registry (2014-2019), patients with NMIBC who received BCG within 1 year prior to BLC were identified. Primary outcomes were recurrences and whether lesions were detected on white light cystoscopy (WLC), BLC or both. We calculated the percentage of cystoscopies with recurrences that were missed with WLC alone. The cystoscopy-level BLC false-positive rate was the proportion of cystoscopies with biopsies only due to BLC suspicious lesions without recurrence. RESULTS: Of 1,703 BLCs, 282 cystoscopies were in the analytic cohort. The overall recurrence rate was 45.0% (127). With only WLC, 13% (16/127) of recurrences would have been missed as 5.7% (16/282) of cystoscopies performed had recurrence only identified with BLC. Among 16 patients with recurrence missed with WLC, 88% (14) had carcinoma in situ. The cystoscopy-level BLC false-positive rate was 5% (15). CONCLUSIONS: BLC helped detect recurrences after recent BCG that would have been missed with WLC alone. Providers should consider BLC for high-risk patients undergoing BCG and should discuss the risk of false-positives with these patients. As clinical trials of novel therapies for BCG-unresponsive disease increase and there are no clear guidelines on BLC use for post-treatment cystoscopies, it is important to consider how variable BLC use could affect enrollment in and comparisons of these studies.


Assuntos
Vacina BCG/uso terapêutico , Cistoscopia/métodos , Recidiva Local de Neoplasia/diagnóstico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Idoso , Biópsia , Carcinoma in Situ/tratamento farmacológico , Feminino , Humanos , Masculino , Estudos Prospectivos , Sistema de Registros , Estados Unidos
4.
BJU Int ; 130(1): 62-67, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34637596

RESUMO

OBJECTIVES: To evaluate the role of blue-light cystoscopy (BLC) in detecting invasive tumours that were not visible on white-light cystoscopy (WLC). PATIENTS AND METHODS: Using the multi-institutional Cysview registry database, patients who had at least one white-light negative (WL-)/blue-light positive (BL+) lesion with invasive pathology (≥T1) as highest stage tumour were identified. All WL-/BL+ lesions and all invasive tumours in the database were used as denominators. Relevant baseline and outcome data were collected. RESULTS: Of the 3514 lesions (1257 unique patients), 818 (23.2%) lesions were WL-/BL+, of those, 55 (7%) lesions were invasive (48 T1, seven T2; 47 unique patients) including 28/55 (51%) de novo invasive lesions (26 unique patients). In all, 21/47 (45%) patients had WL-/BL+ concommitant carcinoma in situ and/or another T1 lesions. Of 22 patients with a WL-/BL+ lesion who underwent radical cystectomy (RC), high-risk pathological features leading to RC was only visible on BLC in 18 (82%) patients. At time of RC, 11/22 (50%) patients had pathological upstaging including four (18%) with node-positive disease. CONCLUSIONS: A considerable proportion of invasive lesions are only detectable by BLC and the rate of pathological upstaging is significant. Our present findings suggest an additional benefit of BLC in the detection of invasive bladder tumours that has implications for treatment approach.


Assuntos
Cistoscopia , Neoplasias da Bexiga Urinária , Cistectomia , Humanos , Sistema de Registros , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
5.
BMC Biol ; 19(1): 203, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526021

RESUMO

BACKGROUND: Silencing of transposable elements (TEs) is essential for maintaining genome stability. Plants use small RNAs (sRNAs) to direct DNA methylation to TEs (RNA-directed DNA methylation; RdDM). Similar mechanisms of epigenetic silencing in the fungal kingdom have remained elusive. RESULTS: We use sRNA sequencing and methylation data to gain insight into epigenetics in the dikaryotic fungus Puccinia graminis f. sp. tritici (Pgt), which causes the devastating stem rust disease on wheat. We use Hi-C data to define the Pgt centromeres and show that they are repeat-rich regions (~250 kb) that are highly diverse in sequence between haplotypes and, like in plants, are enriched for young TEs. DNA cytosine methylation is particularly active at centromeres but also associated with genome-wide control of young TE insertions. Strikingly, over 90% of Pgt sRNAs and several RNAi genes are differentially expressed during infection. Pgt induces waves of functionally diversified sRNAs during infection. The early wave sRNAs are predominantly 21 nts with a 5' uracil derived from genes. In contrast, the late wave sRNAs are mainly 22-nt sRNAs with a 5' adenine and are strongly induced from centromeric regions. TEs that overlap with late wave sRNAs are more likely to be methylated, both inside and outside the centromeres, and methylated TEs exhibit a silencing effect on nearby genes. CONCLUSIONS: We conclude that rust fungi use an epigenetic silencing pathway that might have similarity with RdDM in plants. The Pgt RNAi machinery and sRNAs are under tight temporal control throughout infection and might ensure genome stability during sporulation.


Assuntos
Basidiomycota , Metilação de DNA , Puccinia , Basidiomycota/genética , Centrômero , Metilação de DNA/genética , Elementos de DNA Transponíveis , Instabilidade Genômica , Humanos , Doenças das Plantas/genética , Puccinia/patogenicidade , RNA
6.
Curr Oncol Rep ; 23(9): 105, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34269918

RESUMO

PURPOSE OF REVIEW: Non-muscle-invasive bladder cancer (NMIBC) is a heterogenous malignancy with high recurrence and progression rates, which necessitate uniform recommendations for diagnosis and management. Herein, we review the literature, with an emphasis on guidelines and contemporary diagnostic techniques and interventions. RECENT FINDINGS: Guidelines around the world have adopted a schema which risk-stratify cases at diagnosis, to offer evidence-based treatment and surveillance recommendations. Enhanced endoscopic technologies can improve detection of NMIBC and reduce recurrence. The present Bacillus Calmette-Guerin (BCG) shortage in the USA has led to new strategies to prioritize the most high-risk cases. The entity of BCG-unresponsive high-risk NMIBC remains a challenge to manage, with multiple novel treatments under investigation; fortunately, new therapies have been approved, such as immune checkpoint inhibitors, and others are showing tremendous promise. The standardization of NMIBC management, with evolving detection techniques and therapeutics, offers great potential to improve patient outcomes and survivorship.


Assuntos
Cistoscopia/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/terapia , Bexiga Urinária/patologia , Ensaios Clínicos como Assunto , Humanos , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Equipe de Assistência ao Paciente , Guias de Prática Clínica como Assunto , Fatores de Risco , Resultado do Tratamento
7.
Plant Physiol ; 177(3): 1027-1049, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29844228

RESUMO

Apomixis results in asexual seed formation where progeny are identical to the maternal plant. In ovules of apomictic species of the Hieracium subgenus Pilosella, meiosis of the megaspore mother cell generates four megaspores. Aposporous initial (AI) cells form during meiosis in most ovules. The sexual pathway terminates during functional megaspore (FM) differentiation, when an enlarged AI undergoes mitosis to form an aposporous female gametophyte. Then, the mitotically programmed FM dies along with the three other megaspores by unknown mechanisms. Transcriptomes of laser-dissected AIs, ovule cells, and ovaries from apomicts and AI-deficient mutants were analyzed to understand the pathways involved. The steps leading to AI mitosis and sexual pathway termination were determined using antibodies against arabinogalactan protein epitopes found to mark both sexual and aposporous female gametophyte lineages at inception. At most, four AIs differentiated near developing megaspores. The first expanding AI cell to contact the FM formed a functional AI that underwent mitosis soon after megaspore degeneration. Transcriptome analyses indicated that the enlarged, laser-captured AIs were arrested in the S/G2 phase of the cell cycle and were metabolically active. Further comparisons with AI-deficient mutants showed that AIs were enriched in transcripts encoding homologs of genes involved in, and potentially antagonistic to, known FM specification pathways. We propose that AI and FM cell contact provides cues required for AI mitosis and megaspore degeneration. Specific candidates to further interrogate AI-FM interactions were identified here and include Hieracium arabinogalactan protein family genes.


Assuntos
Apomixia/fisiologia , Asteraceae/fisiologia , Óvulo Vegetal/citologia , Óvulo Vegetal/fisiologia , Proteínas de Plantas/genética , Asteraceae/genética , Metabolismo dos Carboidratos/genética , Ciclo Celular/genética , Enzimas/genética , Enzimas/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Mitose , Mutação , Filogenia , Células Vegetais/imunologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/genética
8.
Plant J ; 89(5): 927-939, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27880012

RESUMO

Hybrids between the Arabidopsis ecotypes C24 and Ler have high levels of hybrid vigour, or heterosis, in both biomass and seed yield. Heterosis can be detected throughout the development of the plant and in different tissues. We examined developing embryos and seeds of C24/Ler reciprocal hybrids with the aim of detecting the earliest time at which heterotic gene activity occurs. In the transcriptomes of 4-dap (days after pollination; dermatogen to globular) and 6-dap (heart) embryos from both parents and hybrids, 95% of expressed genes were at the mid parent value (MPV) and 95% of the genes with single nucleotide polymorphisms between C24 and Ler retained the same relative allelic expression levels in the hybrids as existed in the parents. This included loci that had equivalent levels of transcription in the two parents, together with loci which had different levels of expression in the parents. Amongst the genes which did not have MPV expression levels in the hybrids (non-additively expressed genes), approximately 40 in the globular embryo stage and 89 in the heart embryo stage had altered levels of transcription in both reciprocal hybrids; these genes could contribute to the heterotic phenotype of the hybrid embryo. Many of the non-additively expressed genes had expression levels that were shifted towards maternal levels of transcription, and these differed in the reciprocal hybrids. Allelic expression analysis indicated that most genes with altered allelic contributions in the hybrids had an increase in the expression level of the hybrid's maternal allele. Consistent with the maternal pattern of gene expression, embryo and seed also show maternally influenced phenotypes.


Assuntos
Arabidopsis/embriologia , Arabidopsis/metabolismo , Sementes/embriologia , Sementes/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Sementes/genética , Transcriptoma/genética
9.
New Phytol ; 217(4): 1764-1778, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29243824

RESUMO

The plant apoplast is integral to intercellular signalling, transport and plant-pathogen interactions. Plant pathogens deliver effectors both into the apoplast and inside host cells, but no computational method currently exists to discriminate between these localizations. We present ApoplastP, the first method for predicting whether an effector or plant protein localizes to the apoplast. ApoplastP uncovers features of apoplastic localization common to both effectors and plant proteins, namely depletion in glutamic acid, acidic amino acids and charged amino acids and enrichment in small amino acids. ApoplastP predicts apoplastic localization in effectors with a sensitivity of 75% and a false positive rate of 5%, improving the accuracy of cysteine-rich classifiers by > 13%. ApoplastP does not depend on the presence of a signal peptide and correctly predicts the localization of unconventionally secreted proteins. The secretomes of fungal saprophytes as well as necrotrophic, hemibiotrophic and extracellular fungal pathogens are enriched for predicted apoplastic proteins. Rust pathogens have low proportions of predicted apoplastic proteins, but these are highly enriched for predicted effectors. ApoplastP pioneers apoplastic localization prediction using machine learning. It will facilitate functional studies and will be valuable for predicting if an effector localizes to the apoplast or if it enters plant cells.


Assuntos
Aprendizado de Máquina , Proteínas de Plantas/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Sequência Conservada , Cisteína/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Oomicetos/metabolismo , Proteínas de Plantas/química , Sinais Direcionadores de Proteínas , Proteômica
10.
BMC Biol ; 14(1): 86, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27716180

RESUMO

BACKGROUND: Application of apomixis, or asexual seed formation, in crop breeding would allow rapid fixation of complex traits, economizing improved crop delivery. Identification of apomixis genes is confounded by the polyploid nature, high genome complexity and lack of genomic sequence integration with reproductive tissue transcriptomes in most apomicts. RESULTS: A genomic and transcriptomic resource was developed for Hieracium subgenus Pilosella (Asteraceae) which incorporates characterized sexual, apomictic and mutant apomict plants exhibiting reversion to sexual reproduction. Apomicts develop additional female gametogenic cells that suppress the sexual pathway in ovules. Disrupting small RNA pathways in sexual Arabidopsis also induces extra female gametogenic cells; therefore, the resource was used to examine if changes in small RNA pathways correlate with apomixis initiation. An initial characterization of small RNA pathway genes within Hieracium was undertaken, and ovary-expressed ARGONAUTE genes were identified and cloned. Comparisons of whole ovary transcriptomes from mutant apomicts, relative to the parental apomict, revealed that differentially expressed genes were enriched for processes involved in small RNA biogenesis and chromatin silencing. Small RNA profiles within mutant ovaries did not reveal large-scale alterations in composition or length distributions; however, a small number of differentially expressed, putative small RNA targets were identified. CONCLUSIONS: The established Hieracium resource represents a substantial contribution towards the investigation of early sexual and apomictic female gamete development, and the generation of new candidate genes and markers. Observed changes in small RNA targets and biogenesis pathways within sexual and apomictic ovaries will underlie future functional research into apomixis initiation in Hieracium.


Assuntos
Apomixia/genética , Asteraceae/genética , RNA de Plantas/genética , Apomixia/fisiologia , Asteraceae/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Óvulo Vegetal/genética , Óvulo Vegetal/fisiologia , Sementes/genética , Sementes/fisiologia
11.
Plant Cell Physiol ; 57(1): 125-37, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26589268

RESUMO

Chinese tallow (Triadica sebifera) is a valuable oilseed-producing tree that can grow in a variety of conditions without competing for food production, and is a promising biofuel feedstock candidate. The fruits are unique in that they contain both saturated and unsaturated fat present in the tallow and seed layer, respectively. The tallow layer is poorly studied and is considered only as an external fatty deposition secreted from the seed. In this study we show that tallow is in fact a non-seed cellular tissue capable of triglyceride synthesis. Knowledge of lipid synthesis and storage mechanisms in tissues other than seed is limited but essential to generate oil-rich biomass crops. Here, we describe the annotated transcriptome assembly generated from the fruit coat, tallow and seed tissues of Chinese tallow. The final assembly was functionally annotated, allowing for the identification of candidate genes and reconstruction of lipid pathways. A tallow tissue-specific paralog for the transcription factor gene WRINKLED1 (WRI1) and lipid droplet-associated protein genes, distinct from those expressed in seed tissue, were found to be active in tallow, underpinning the mode of oil synthesis and packaging in this tissue. Our data have established an excellent knowledge base that can provide genetic and biochemical insights for engineering non-seed tissues to accumulate large amounts of oil. In addition to the large data set of annotated transcripts, the study also provides gene-based simple sequence repeat and single nucleotide polymorphism markers.


Assuntos
Euphorbiaceae/genética , Ácidos Graxos/metabolismo , Óleos de Plantas/metabolismo , Transcriptoma , Biocombustíveis , Euphorbiaceae/metabolismo , Euphorbiaceae/ultraestrutura , Ácidos Graxos/análise , Frutas/genética , Frutas/metabolismo , Frutas/ultraestrutura , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Metabolismo dos Lipídeos , Lipídeos/análise , Anotação de Sequência Molecular , Especificidade de Órgãos , Óleos de Plantas/análise , Proteínas de Plantas/genética , Sementes/genética , Sementes/metabolismo , Sementes/ultraestrutura , Análise de Sequência de DNA
12.
BMC Plant Biol ; 16: 45, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26882898

RESUMO

BACKGROUND: Heterosis or hybrid vigour is a phenomenon in which hybrid progeny exhibit superior performance compared to their parental inbred lines. Most commercial Chinese cabbage cultivars are F1 hybrids and their level of hybrid vigour is of critical importance and is a key selection criterion in the breeding system. RESULTS: We have characterized the heterotic phenotype of one F1 hybrid cultivar of Chinese cabbage and its parental lines from early- to late-developmental stages of the plants. Hybrid cotyledons are larger than those of the parents at 4 days after sowing and biomass in the hybrid, determined by the fresh weight of leaves, is greater than that of the larger parent line by approximately 20% at 14 days after sowing. The final yield of the hybrid harvested at 63 days after sowing is 25% greater than the yield of the better parent. The larger leaves of the hybrid are a consequence of increased cell size and number of the photosynthetic palisade mesophyll cells and other leaf cells. The accumulation of plant hormones in the F1 was within the range of the parental levels at both 2 and 10 days after sowing. Two days after sowing, the expression levels of chloroplast-targeted genes in the cotyledon cells were upregulated in the F1 hybrid relative to their mid parent values. Shutdown of chlorophyll biosynthesis in the cotyledon by norflurazon prevented the increased leaf area in the F1 hybrid. CONCLUSIONS: In the cotyledons of F1 hybrids, chloroplast-targeted genes were upregulated at 2 days after sowing. The increased activity levels of this group of genes suggested that their differential transcription levels could be important for establishing early heterosis but the increased transcription levels were transient. Inhibition of the photosynthetic process in the cotyledon reduced heterosis in later seedling stages. These observations suggest early developmental events in the germinating seedling of the hybrid may be important for later developmental vigour and yield advantage.


Assuntos
Brassica/genética , Produtos Agrícolas/genética , Vigor Híbrido , Perfilação da Expressão Gênica , Genes de Plantas , Reguladores de Crescimento de Plantas/genética , RNA de Plantas
14.
New Phytol ; 210(2): 743-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26680733

RESUMO

Eukaryotic filamentous plant pathogens secrete effector proteins that modulate the host cell to facilitate infection. Computational effector candidate identification and subsequent functional characterization delivers valuable insights into plant-pathogen interactions. However, effector prediction in fungi has been challenging due to a lack of unifying sequence features such as conserved N-terminal sequence motifs. Fungal effectors are commonly predicted from secretomes based on criteria such as small size and cysteine-rich, which suffers from poor accuracy. We present EffectorP which pioneers the application of machine learning to fungal effector prediction. EffectorP improves fungal effector prediction from secretomes based on a robust signal of sequence-derived properties, achieving sensitivity and specificity of over 80%. Features that discriminate fungal effectors from secreted noneffectors are predominantly sequence length, molecular weight and protein net charge, as well as cysteine, serine and tryptophan content. We demonstrate that EffectorP is powerful when combined with in planta expression data for predicting high-priority effector candidates. EffectorP is the first prediction program for fungal effectors based on machine learning. Our findings will facilitate functional fungal effector studies and improve our understanding of effectors in plant-pathogen interactions. EffectorP is available at http://effectorp.csiro.au.


Assuntos
Algoritmos , Biologia Computacional/métodos , Proteínas Fúngicas/metabolismo , Aprendizado de Máquina , Aminoácidos/metabolismo , Citoplasma/metabolismo , Proteínas Fúngicas/química , Fusarium/metabolismo , Genoma Fúngico , Peso Molecular , Reprodutibilidade dos Testes , Especificidade da Espécie
15.
Development ; 139(8): 1399-404, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22399683

RESUMO

Female gamete development in Arabidopsis ovules comprises two phases. During megasporogenesis, a somatic ovule cell differentiates into a megaspore mother cell and undergoes meiosis to produce four haploid megaspores, three of which degrade. The surviving functional megaspore participates in megagametogenesis, undergoing syncytial mitosis and cellular differentiation to produce a multicellular female gametophyte containing the egg and central cell, progenitors of the embryo and endosperm of the seed. The transition between megasporogenesis and megagametogenesis is poorly characterised, partly owing to the inaccessibility of reproductive cells within the ovule. Here, laser capture microdissection was used to identify genes expressed in and/or around developing megaspores during the transition to megagametogenesis. ARGONAUTE5 (AGO5), a putative effector of small RNA (sRNA) silencing pathways, was found to be expressed around reproductive cells during megasporogenesis, and a novel semi-dominant ago5-4 insertion allele showed defects in the initiation of megagametogenesis. Expression of a viral RNAi suppressor, P1/Hc-Pro, driven by the WUSCHEL and AGO5 promoters in somatic cells flanking the megaspores resulted in a similar phenotype. This indicates that sRNA-dependent pathways acting in somatic ovule tissues promote the initiation of megagametogenesis in the functional megaspore. Notably, these pathways are independent of AGO9, which functions in somatic epidermal ovule cells to inhibit the formation of multiple megaspore-like cells. Therefore, one somatic sRNA pathway involving AGO9 restricts reproductive development to the functional megaspore and a second pathway, inhibited by ago5-4 and P1/Hc-Pro, promotes megagametogenesis.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Mitose , RNA de Plantas/metabolismo , Proteínas de Ligação a RNA/genética , Alelos , Animais , Proteínas Argonautas/genética , Endosperma/metabolismo , Feminino , Flores , Regulação da Expressão Gênica no Desenvolvimento , Genes de Plantas , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Interferência de RNA , Sementes/metabolismo
16.
Bioinformatics ; 30(2): 151-6, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24262213

RESUMO

MOTIVATION: We have recently characterized an instance of alternative splicing that differs from the canonical gene transcript by deletion of a length of sequence not divisible by three, but where translation can be rescued by an alternative start codon. This results in a predicted protein in which the amino terminus differs markedly in sequence from the known protein product(s), as it is translated from an alternative reading frame. Automated pipelines have annotated thousands of splice variants but have overlooked these protein isoforms, leading to them being underrepresented in current databases. RESULTS: Here we describe 1849 human and 733 mouse transcripts that can be transcribed from an alternate ATG. Of these, >80% have not been annotated previously. Those conserved between human and mouse genomes (and hence under likely evolutionary selection) are identified. We provide mass spectroscopy evidence for translation of selected transcripts. Of the described splice variants, only one has previously been studied in detail and converted the encoded protein from an activator of cell-function to a suppressor, demonstrating that these splice variants can result in profound functional change. We investigate the potential functional effects of this splicing using a variety of bioinformatic tools. The 2582 variants we describe are involved in a wide variety of biological processes, and therefore open many new avenues of research.


Assuntos
Processamento Alternativo , Biologia Computacional , Regulação da Expressão Gênica , Genoma , Proteínas/metabolismo , Sítios de Splice de RNA/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Isoformas de Proteínas , Proteínas/genética
17.
NMR Biomed ; 28(11): 1357-65, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26373461

RESUMO

Cerebral ischemia sets off a cascade of neuronal and metabolic responses to preserve brain viability. An understanding of the temporal evolution of these changes during and after ischemia, and their correlation with hemodynamic changes, is essential. In this study, a 12-min whole-brain ischemia based on the four-blood-vessel occlusion model was employed in rats. Using a high-temporal-resolution simultaneous (1)H-(31)P MRS acquisition sequence at 9.4 T, we investigated dynamic occlusion and reperfusion responses in cerebral lactate (Lac), phosphocreatine (PCr), adenosine triphosphate (ATP), pH, and blood oxygenation level dependence (BOLD), together with changes in neuronal field potential activity. We reveal tightly coupled dynamics between hemodynamic, metabolic, and neuronal responses to ischemia. Neuronal activity, BOLD, PCr, Lac, and pH changed immediately following occlusion, indicating reduced energy substrates and consumption, and increased glycolysis to maintain cellular ATP levels, which started to decrease 2.2 min after the onset of occlusion. ATP stores were then gradually consumed to maintain a minimum housekeeping neuronal activity level. By correlating dynamic changes of brain activity, BOLD, and energy metabolism, new insights into the brain's survival ability and mechanisms during an acute ischemic attack from the perspectives of cerebral metabolism, neuroenergetics, and neuronal activity were gained.


Assuntos
Trifosfato de Adenosina/metabolismo , Isquemia Encefálica/fisiopatologia , Encéfalo/fisiopatologia , Circulação Cerebrovascular , Neurônios , Consumo de Oxigênio , Doença Aguda , Animais , Velocidade do Fluxo Sanguíneo , Encéfalo/patologia , Isquemia Encefálica/patologia , Eletroencefalografia/métodos , Masculino , Taxa de Depuração Metabólica , Isótopos de Fósforo/farmacocinética , Espectroscopia de Prótons por Ressonância Magnética/métodos , Ratos , Ratos Sprague-Dawley , Estatística como Assunto
18.
Ann Bot ; 115(4): 567-80, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25538115

RESUMO

BACKGROUND AND AIMS: Apomixis in plants generates clonal progeny with a maternal genotype through asexual seed formation. Hieracium subgenus Pilosella (Asteraceae) contains polyploid, highly heterozygous apomictic and sexual species. Within apomictic Hieracium, dominant genetic loci independently regulate the qualitative developmental components of apomixis. In H. praealtum, LOSS OF APOMEIOSIS (LOA) enables formation of embryo sacs without meiosis and LOSS OF PARTHENOGENESIS (LOP) enables fertilization-independent seed formation. A locus required for fertilization-independent endosperm formation (AutE) has been identified in H. piloselloides. Additional quantitative loci appear to influence the penetrance of the qualitative loci, although the controlling genes remain unknown. This study aimed to develop the first genetic linkage maps for sexual and apomictic Hieracium species using simple sequence repeat (SSR) markers derived from expressed transcripts within the developing ovaries. METHODS: RNA from microdissected Hieracium ovule cell types and ovaries was sequenced and SSRs were identified. Two different F1 mapping populations were created to overcome difficulties associated with genome complexity and asexual reproduction. SSR markers were analysed within each mapping population to generate draft linkage maps for apomictic and sexual Hieracium species. KEY RESULTS: A collection of 14 684 Hieracium expressed SSR markers were developed and linkage maps were constructed for Hieracium species using a subset of the SSR markers. Both the LOA and LOP loci were successfully assigned to linkage groups; however, AutE could not be mapped using the current populations. Comparisons with lettuce (Lactuca sativa) revealed partial macrosynteny between the two Asteraceae species. CONCLUSIONS: A collection of SSR markers and draft linkage maps were developed for two apomictic and one sexual Hieracium species. These maps will support cloning of controlling genes at LOA and LOP loci in Hieracium and should also assist with identification of quantitative loci that affect the expressivity of apomixis. Future work will focus on mapping AutE using alternative populations.


Assuntos
Apomixia , Asteraceae/fisiologia , Repetições de Microssatélites , Proteínas de Plantas/genética , Locos de Características Quantitativas , Asteraceae/genética , Asteraceae/crescimento & desenvolvimento , Mapeamento Cromossômico , Marcadores Genéticos , Haploidia , Hibridização Genética , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/metabolismo , Proteínas de Plantas/metabolismo , Poliploidia
19.
Brain ; 137(Pt 10): 2649-56, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25070514

RESUMO

Cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) is a recently recognized neurodegenerative ganglionopathy. Prompted by the presence of symptomatic postural hypotension in two patients with CANVAS, we hypothesized that autonomic dysfunction may be an associated feature of the syndrome. We assessed symptoms of autonomic dysfunction and performed autonomic nervous system testing among 26 patients from New Zealand. After excluding three patients with diabetes mellitus, 83% had evidence of autonomic dysfunction; all patients had at least one autonomic symptom and 91% had more than two symptoms. We also found a higher rate of downbeat nystagmus (65%) than previously described in CANVAS. We confirmed that sensory findings on nerve conduction tests were consistent with a sensory ganglionopathy and describe two patients with loss of trigeminal sensation consistent with previous pathological descriptions of trigeminal sensory ganglionopathy. Our results suggest that autonomic dysfunction is a major feature of CANVAS. This has implications for the management of patients with CANVAS as the autonomic symptoms may be amenable to treatment. The findings also provide an important differential diagnosis from multiple system atrophy for patients who present with ataxia and autonomic failure.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Ataxia Cerebelar/fisiopatologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Doenças Vestibulares/fisiopatologia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doenças do Sistema Nervoso Autônomo/complicações , Ataxia Cerebelar/complicações , Tontura/fisiopatologia , Feminino , Força da Mão/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Nova Zelândia , Nistagmo Patológico/etiologia , Nistagmo Patológico/fisiopatologia , Doenças do Sistema Nervoso Periférico/complicações , Reflexo Vestíbulo-Ocular/fisiologia , Síndrome , Manobra de Valsalva , Doenças Vestibulares/etiologia , Testes de Função Vestibular , Vitamina E/sangue , Adulto Jovem
20.
Proc Natl Acad Sci U S A ; 109(18): 7109-14, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22493265

RESUMO

Arabidopsis thaliana shows hybrid vigor (heterosis) in progeny of crosses between Columbia-0 and C24 accessions. Hybrid vigor was evident as early as mature seeds and in seedlings 3 d after sowing (DAS). At 3 DAS, genes encoding chloroplast-located proteins were significantly overrepresented (187) among the 724 genes that have greater than midparent values of expression in the hybrid. Many of these genes are involved in chlorophyll biosynthesis and photosynthesis. The rate of photosynthesis was constant per unit leaf area in parents and hybrids. Larger cell sizes in the hybrids were associated with more chloroplasts per cell, more total chlorophyll, and more photosynthesis. The increased transcription of the chloroplast-targeted genes was restricted to the 3-7 DAS period. At 10 DAS, only 118 genes had expression levels different from the expected midparent value in the hybrid, and only 12 of these genes were differentially expressed at 3 DAS. The early increase in activity of genes involved in photosynthesis and the associated phenomena of increases in cell size and number through development, leading to larger leaf areas of all leaves in the hybrid, suggest a central role for increased photosynthesis in the production of the heterotic biomass. In support of this correlation, we found that an inhibitor of photosynthesis eliminated heterosis and that higher light intensities enhanced both photosynthesis and heterosis. In hybrids with low-level heterosis (Landsberg erecta x Columbia-0), chloroplast-targeted genes were not up-regulated and leaf areas were only marginally increased.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Vigor Híbrido/genética , Vigor Híbrido/fisiologia , Fotossíntese/genética , Fotossíntese/fisiologia , Arabidopsis/crescimento & desenvolvimento , Biomassa , Contagem de Células , Tamanho Celular , Clorofila/biossíntese , Clorofila/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Folhas de Planta/citologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo
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