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1.
Genome Biol ; 25(1): 161, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898465

RESUMO

BACKGROUND: Neuroblastoma is a common pediatric cancer, where preclinical studies suggest that a mesenchymal-like gene expression program contributes to chemotherapy resistance. However, clinical outcomes remain poor, implying we need a better understanding of the relationship between patient tumor heterogeneity and preclinical models. RESULTS: Here, we generate single-cell RNA-seq maps of neuroblastoma cell lines, patient-derived xenograft models (PDX), and a genetically engineered mouse model (GEMM). We develop an unsupervised machine learning approach ("automatic consensus nonnegative matrix factorization" (acNMF)) to compare the gene expression programs found in preclinical models to a large cohort of patient tumors. We confirm a weakly expressed, mesenchymal-like program in otherwise adrenergic cancer cells in some pre-treated high-risk patient tumors, but this appears distinct from the presumptive drug-resistance mesenchymal programs evident in cell lines. Surprisingly, however, this weak-mesenchymal-like program is maintained in PDX and could be chemotherapy-induced in our GEMM after only 24 h, suggesting an uncharacterized therapy-escape mechanism. CONCLUSIONS: Collectively, our findings improve the understanding of how neuroblastoma patient tumor heterogeneity is reflected in preclinical models, provides a comprehensive integrated resource, and a generalizable set of computational methodologies for the joint analysis of clinical and pre-clinical single-cell RNA-seq datasets.


Assuntos
Neuroblastoma , RNA-Seq , Análise de Célula Única , Neuroblastoma/genética , Neuroblastoma/patologia , Humanos , Animais , Análise de Célula Única/métodos , Camundongos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Resistencia a Medicamentos Antineoplásicos/genética , Transcriptoma , Análise da Expressão Gênica de Célula Única
2.
bioRxiv ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38712039

RESUMO

Neuroblastoma is a common pediatric cancer, where preclinical studies suggest that a mesenchymal-like gene expression program contributes to chemotherapy resistance. However, clinical outcomes remain poor, implying we need a better understanding of the relationship between patient tumor heterogeneity and preclinical models. Here, we generated single-cell RNA-seq maps of neuroblastoma cell lines, patient-derived xenograft models (PDX), and a genetically engineered mouse model (GEMM). We developed an unsupervised machine learning approach ('automatic consensus nonnegative matrix factorization' (acNMF)) to compare the gene expression programs found in preclinical models to a large cohort of patient tumors. We confirmed a weakly expressed, mesenchymal-like program in otherwise adrenergic cancer cells in some pre-treated high-risk patient tumors, but this appears distinct from the presumptive drug-resistance mesenchymal programs evident in cell lines. Surprisingly however, this weak-mesenchymal-like program was maintained in PDX and could be chemotherapy-induced in our GEMM after only 24 hours, suggesting an uncharacterized therapy-escape mechanism. Collectively, our findings improve the understanding of how neuroblastoma patient tumor heterogeneity is reflected in preclinical models, provides a comprehensive integrated resource, and a generalizable set of computational methodologies for the joint analysis of clinical and pre-clinical single-cell RNA-seq datasets.

3.
J Biomater Appl ; 39(1): 24-39, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38616137

RESUMO

The reparative properties of amniotic membrane allografts are well-suited for a broad spectrum of specialties. Further enhancement of their utility can be achieved by designing to the needs of each application through the development of novel processing techniques and tissue configurations. As such, this study evaluated the material characteristics and biological properties of two PURION® processed amniotic membrane products, a lyophilized human amnion, intermediate layer, and chorion membrane (LHACM) and a dehydrated human amnion, chorion membrane (DHACM). LHACM is thicker; therefore, its handling properties are ideal for deep, soft tissue deficits; whereas DHACM is more similar to a film-like overlay and may be used for shallow defects or surgical on-lays. Characterization of the similarities and differences between LHACM and DHACM was conducted through a series of in vitro and in vivo studies relevant to the healing cascade. Compositional analysis was performed through histological staining along with assessment of barrier membrane properties through equilibrium dialysis. In vitro cellular response was assessed in fibroblasts and endothelial cells using cell proliferation, migration, and metabolic assays. The in vivo cellular response was assessed in an athymic nude mouse subcutaneous implantation model. The results indicated the PURION® process preserved the native membrane structure, nonviable cells and collagen distributed in the individual layers of both products. Although, LHACM is thicker than DHACM, a similar composition of growth factors, cytokines, chemokines and proteases is retained and consequently elicit comparable in vitro and in vivo cellular responses. In culture, both treatments behaved as potent mitogens, chemoattractants and stimulants, which translated to the promotion of cellular infiltration, neocollagen deposition and angiogenesis in a murine model. PURION® processed LHACM and DHACM differ in physical properties but possess similar in vitro and in vivo activities highlighting the impact of processing method on the versatility of clinical use of amniotic membrane allografts.


Assuntos
Aloenxertos , Âmnio , Córion , Camundongos Nus , Córion/citologia , Âmnio/química , Animais , Humanos , Camundongos , Cicatrização , Proliferação de Células , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Teste de Materiais , Movimento Celular
7.
PLoS One ; 18(8): e0290281, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37611008

RESUMO

Adoption of electronic identification ear tags (EID) and DNA testing by commercial range sheep producers in the Western United States has been low, despite the availability of these technologies for over a decade. Jointly, these technologies offer an approach to provide individual animal performance data to improve flock health, genetic and reproductive management. This project involved a collaboration with five California sheep producers representing a broad geographic range, varying levels of pre-project EID adoption, and diverse operational practices. Tissue samples were collected from, and ear EIDs were placed in, a total of 2,936 rams and their potential lambs. We partnered with a commercial packing company, Superior Farms, to genotype the animals. Superior Farms used a targeted genotyping panel to assign parentage, and link individual animal identification (ID) to camera-graded carcass measurements. This enabled the collection of individual progeny carcass data and provided insight into sire performance, providing for the within-flock identification of prolific sires that were producing lambs with significantly more saleable meat as compared to their flock mates. Overall, almost 91% of lambs were successfully matched to their sire, and prolificacy ranging from 0-135 lambs per ram. There was as much as an $80 difference in the average edible product from camera-graded carcasses derived from lamb groups sired by different rams. A partial budget analysis modeling investment in an EID system coupled with an autodrafter and scale to collect individual weights and improve labor efficiency during processing, and a sheep flip chute to improve worker safety during foot trimmings, yielded a greater than 7:1 return on investment over a five-year time frame. Ideally, the data collection enabled by EIDs and DNA testing would feed into data-driven genetic evaluation programs to enable selection for more productive and profitable animals, and allow the US sheep industry to accelerate the rate of genetic improvement.


Assuntos
Testes Genéticos , Carneiro Doméstico , Ovinos/genética , Animais , Masculino , Indústrias , Bandagens , Eletrônica
8.
Br J Dermatol ; 189(1): 91-102, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-36972303

RESUMO

BACKGROUND: Ichthyosis defines a group of chronic conditions that manifest phenotypically as a thick layer of scales, often affecting the entire skin. While the gene mutations that lead to ichthyosis are well documented, the actual signalling mechanisms that lead to scaling are poorly characterized; however, recent publications suggest that common mechanisms are active in ichthyotic tissue and in analogous models of ichthyosis. OBJECTIVES: To determine common mechanisms of hyperkeratosis that may be easily targeted with small-molecule inhibitors. METHODS: We combined gene expression analysis of gene-specific short hairpin RNA (shRNA) knockdowns in rat epidermal keratinocytes (REKs) of two genes mutated in autosomal recessive congenital ichthyosis (ARCI), Tgm1 and Alox12b, and proteomic analysis of skin scale from patients with ARCI, as well as RNA sequencing data from rat epidermal keratinocytes treated with the Toll-like receptor 2 (TLR2) agonist Pam3CSK4. RESULTS: We identified common activation of the TLR2 pathway. Exogenous TLR2 activation led to increased expression of important cornified envelope genes and, in organotypic culture, caused hyperkeratosis. Conversely, blockade of TLR2 signalling in keratinocytes from patients with ichthyosis and our shRNA models reduced the expression of keratin 1, a structural protein overexpressed in ichthyosis scale. A time course of TLR2 activation in REKs revealed that although there was rapid initial activation of innate immune pathways, this was rapidly superseded by widespread upregulation of epidermal differentiation-related proteins. Both nuclear factor kappa B phosphorylation and GATA3 upregulation was associated with this switch, and GATA3 overexpression was sufficient to increase keratin 1 expression. CONCLUSIONS: Taken together, these data define a dual role for TLR2 activation during epidermal barrier repair that may be a useful therapeutic modality in treating diseases of epidermal barrier dysfunction.


Assuntos
Ictiose , Receptor 2 Toll-Like , Animais , Ratos , Ictiose/genética , Queratina-1/genética , Mutação , Fenótipo , Proteômica , RNA Interferente Pequeno , Receptor 2 Toll-Like/genética
9.
Front Plant Sci ; 12: 637956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815444

RESUMO

Brachiaria (Trin.) Griseb. (syn. Urochloa P. Beauv.) is a C4 grass genus belonging to the Panicoideae. Native to Africa, these grasses are now widely grown as forages in tropical areas worldwide and are the subject of intensive breeding, particularly in South America. Tolerance to abiotic stresses such as aluminum and drought are major breeding objectives. In this study, we present the transcriptomic profiling of leaves and roots of three Brachiaria interspecific hybrid genotypes with the onset of water stress, Br12/3659-17 (gt-17), Br12/2360-9 (gt-9), and Br12/3868-18 (gt-18), previously characterized as having good, intermediate and poor tolerance to drought, respectively, in germplasm evaluation programs. RNA was extracted from leaf and root tissue of plants at estimated growing medium water contents (EWC) of 35, 15, and 5%. Differentially expressed genes (DEGs) were compared between different EWCs, 35/15, 15/5, and 35/5 using DESeq2. Overall, the proportions of DEGs enriched in all three genotypes varied in a genotype-dependent manner in relation to EWC comparison, with intermediate and sensitive gt-9 and gt-18 being more similar to each other than to drought tolerant gt-17. More specifically, GO terms relating to carbohydrate and cell wall metabolism in the leaves were enriched by up-regulated DEGs in gt-9 and gt-18, but by down-regulated DEGs in gt-17. Across all genotypes, analysis of DEG enzyme activities indicated an excess of down-regulated putative apoplastic peroxidases in the roots as water stress increased. This suggests that changes in root cell-wall architecture may be an important component of the response to water stress in Brachiaria.

10.
PLoS One ; 16(4): e0249636, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33831050

RESUMO

Ryegrasses (Lolium spp.) and fescues (Festuca spp.) are closely related and widely cultivated perennial forage grasses. As such, resilience in the face of abiotic stresses is an important component of their traits. We have compared patterns of differentially expressed genes (DEGs) in roots and leaves of two perennial ryegrass genotypes and a single genotype of each of a festulolium (predominantly Italian ryegrass) and meadow fescue with the onset of water stress, focussing on overall patterns of DEGs and gene ontology terms (GOs) shared by all four genotypes. Plants were established in a growing medium of vermiculite watered with nutrient solution. Leaf and root material were sampled at 35% (saturation) and, as the medium dried, at 15%, 5% and 1% estimated water contents (EWCs) and RNA extracted. Differential gene expression was evaluated comparing the EWC sampling points from RNAseq data using a combination of analysis methods. For all genotypes, the greatest numbers of DEGs were identified in the 35/1 and 5/1 comparisons in both leaves and roots. In total, 566 leaf and 643 root DEGs were common to all 4 genotypes, though a third of these leaf DEGs were not regulated in the same up/down direction in all 4 genotypes. For roots, the equivalent figure was 1% of the DEGs. GO terms shared by all four genotypes were often enriched by both up- and down-regulated DEGs in the leaf, whereas generally, only by either up- or down-regulated DEGs in the root. Overall, up-regulated leaf DEGs tended to be more genotype-specific than down-regulated leaf DEGs or root DEGs and were also associated with fewer GOs. On average, only 5-15% of the DEGs enriching common GO terms were shared by all 4 genotypes, suggesting considerable variation in DEGs between related genotypes in enacting similar biological processes.


Assuntos
Desidratação , Festuca/metabolismo , Regulação da Expressão Gênica de Plantas , Lolium/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Festuca/genética , Festuca/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Ontologia Genética , Genótipo , Lolium/genética , Lolium/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
11.
Intern Med J ; 50(12): 1475-1482, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32043739

RESUMO

BACKGROUND: Central venous access devices (CVAD) are commonly employed in the management of cancer patients. While having several benefits they are associated with significant risks. AIM: To review the incidence and risk factors for catheter-related thrombosis (CRT) in cancer patients with a CVAD. METHODS: We performed a prospective observational cohort study of adult patients with cancer requiring a CVAD between 1 January 2004 and 29 June 2016. The rate of, and risk factors for the development of, symptomatic CRT were evaluated. RESULTS: A total of 4920 central lines was inserted into 3130 patients. The incidence of CRT was 3.6%. CRT developed a median of 12 days following line insertion. Peripherally inserted central catheters (PICC) were associated with the highest rates of CRT (hazards ratio (HR) 22.2, 95% confidence interval (CI) 2.9-170.6). Older age groups developed CRT at lower rates (HR 0.57; 95% CI 0.39-0.84 for age 50-61 years, and HR 0.63; 95% CI 0.45-0.89 for age >61 years) compared to age <50 years. Increased CRT was seen in patients with prior CRT (HR 1.81; 95% CI 1.19-2.77). There was a trend to more CRT events with a Khorana tumour score of 1 compared to those with a score of 0 (HR 1.37, 95% CI 1.00-1.88). Hodgkin lymphoma, germ cell and oesophagus cancers had the highest CRT rates. Side of insertion was not associated with thrombosis risk (HR 0.77; 95% CI 0.57-1.05; P = 0.10). CONCLUSIONS: Age <50 years, PICC lines and prior CRT were associated with highest CRT rate. Cancer subtype and insertion side were not predictive of thrombosis.


Assuntos
Cateterismo Venoso Central , Neoplasias , Trombose , Adulto , Idoso , Cateterismo Venoso Central/efeitos adversos , Humanos , Incidência , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Estudos Prospectivos , Fatores de Risco , Trombose/epidemiologia , Trombose/etiologia
12.
JAMA Pediatr ; 174(1): 29-37, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31764962

RESUMO

Importance: Systemic treatments for severe childhood atopic dermatitis have limited evidence and/or are unlicensed. Despite the efficacy of anti-IgE medication (omalizumab) in the treatment of atopy, no large randomized studies in childhood atopic dermatitis have been published. Objective: To determine the effectiveness of omalizumab in treating severe atopic dermatitis in children. Design, Setting, and Participants: The Atopic Dermatitis Anti-IgE Pediatric Trial (ADAPT) was a 24-week single-center, double-blind, placebo-controlled randomized clinical trial with a 24-week follow-up. Conducted from November 20, 2014, to August 31, 2017, at Guy's and St Thomas' Hospital NHS Foundation Trust and King's College London in the United Kingdom, this trial recruited participants after a screening visit. Eligible participants (n = 62) were aged 4 to 19 years and had severe eczema (with objective Scoring Atopic Dermatitis [SCORAD] index >40) that was unresponsive to optimum therapy. Statistical analysis was conducted using the intention-to-treat principle. Interventions: Subcutaneous omalizumab or placebo for 24 weeks. The drug manufacturer's dosing tables were used to determine the dosage based on total IgE (30-1500 IU/mL) and body weight (in kilograms) at randomization. Main Outcomes and Measures: Objective SCORAD index after 24 weeks of treatment. Results: In total, 62 children (mean [SD] age, 10.3 [4.2] years; 32 (52%) were male) were randomized to either omalizumab (n = 30) or placebo (n = 32). Five participants withdrew from treatment (4 [13%] from the placebo group, and 1 [3%] from the omalizumab group). Follow-up attendance was 97% at week 24 and 98% at week 48. After adjustment for baseline objective SCORAD index, age, and IgE level, the mean difference in objective SCORAD index improvement between groups at week 24 was -6.9 (95% CI, -12.2 to -1.5; P = .01), significantly favoring omalizumab therapy and reflecting the results in other assessments of atopic dermatitis severity. Improved quality-of-life scores were seen in the omalizumab group, as measured by the Children's Dermatology Life Quality Index/Dermatology Life Quality Index (-3.5; 95% CI, -6.4 to -0.5) and Pediatric Allergic Disease Quality of Life Questionnaire score (-0.5; 95% CI, -0.9 to -0.0). Improvements in disease severity occurred despite lower potent topical corticosteroid use in the omalizumab group compared with the placebo group (median [interquartile range (IQR)] percentage of body surface area covered, 16% [10%-46%] vs 31% [14%-55%]; median [IQR] number of days of use, 109 [34-164] days vs 161 [82-171] days). Conclusions and Relevance: This randomized clinical trial found that omalizumab significantly reduced atopic dermatitis severity and improved quality of life in a pediatric population with atopy and severe eczema despite highly elevated total IgE levels at baseline. The result was associated with a potent topical corticosteroid sparing effect and may suggest that omalizumab is a treatment option for difficult-to-manage severe eczema in children with atopy. Trial Registration: ClinicalTrials.gov identifier: NCT02300701.


Assuntos
Dermatite Atópica/tratamento farmacológico , Omalizumab/administração & dosagem , Qualidade de Vida , Administração Tópica , Adolescente , Antialérgicos/administração & dosagem , Criança , Pré-Escolar , Dermatite Atópica/diagnóstico , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
13.
PLoS One ; 14(7): e0220518, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361773

RESUMO

Perennial ryegrass (Lolium perenne) is a forage and amenity grass species widely cultivated in temperate regions worldwide. As such, perennial ryegrass populations are exposed to a range of environmental conditions and stresses on a seasonal basis and from year to year. One source of potential stress is limitation on water availability. The ability of these perennial grasses to be able to withstand and recover after periods of water limitation or drought can be a key component of grassland performance. Thus, we were interested in looking at changes in patterns of gene expression associated with increasing water stress. Clones of a single genotype of perennial ryegrass were grown under non-flowering growth room conditions in vermiculite supplemented with nutrient solution. Leaf and root tissue was sampled at 4 times in quadruplicate relating to estimated water contents of 35%, 15%, 5% and 1%. RNA was extracted and RNAseq used to generate transcriptome profiles at each sampling point. Transcriptomes were assembled using the published reference genome sequence and differential gene expression analysed using 3 different programmes, DESeq2, edgeR and limma (with the voom transformation), individually and in combination, deriving Early, Middle and Late stage comparisons. Identified differentially expressed genes were then associated with enriched GO terms using BLAST2GO. For the leaf, up-regulated differentially expressed genes were strongly associated with GO terms only during the Early stage and the majority of GO terms were associated with only down-regulated genes at the Middle or Late stages. For the roots, few differentially expressed genes were identified at either Early or Middle stages. Only one replicate at 1% estimated water content produced high quality data for the root, however, this indicated a high level of differential expression. Again the majority of enriched GO terms were associated with down-regulated genes. The performance of the different analysis programmes and the annotations associated with identified differentially expressed genes is discussed.


Assuntos
Desidratação , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Lolium/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , Transcriptoma , Secas , Perfilação da Expressão Gênica , Genótipo , Lolium/crescimento & desenvolvimento , Lolium/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
14.
Hum Gene Ther ; 30(9): 1067-1078, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288584

RESUMO

Netherton syndrome (NS) is a rare autosomal recessive skin disorder caused by mutations in SPINK5. It is a debilitating condition with notable mortality in the early years of life. There is no curative treatment. We undertook a nonrandomized, open-label, feasibility, and safety study using autologous keratinocytes transduced with a lentiviral vector encoding SPINK5 under the control of the human involucrin promoter. Six NS subjects were recruited, and gene-modified epithelial sheets were successfully generated in three of five subjects. The sheets exhibited expression of correctly sized lympho-epithelial Kazal-type-related inhibitor (LEKTI) protein after modification. One subject was grafted with a 20 cm2 gene-modified graft on the left anterior thigh without any adverse complications and was monitored by serial sampling for 12 months. Recovery within the graft area was compared against an area outside by morphology, proviral copy number and expression of the SPINK5 encoded protein, LEKTI, and its downstream target kallikrein 5, which exhibited transient functional correction. The study confirmed the feasibility of generating lentiviral gene-modified epidermal sheets for inherited skin diseases such as NS, but sustained LEKTI expression is likely to require the identification, targeting, and engraftment of long-lived keratinocyte stem cell populations for durable therapeutic effects. Important learning points for the application of gene-modified epidermal sheets are discussed.


Assuntos
Células Epidérmicas/metabolismo , Epiderme/metabolismo , Epiderme/transplante , Síndrome de Netherton/genética , Síndrome de Netherton/terapia , Transdução Genética , Transgenes , Adolescente , Adulto , Autoenxertos , Biomarcadores , Técnicas de Cultura de Células , Feminino , Imunofluorescência , Expressão Gênica , Engenharia Genética , Terapia Genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Queratinócitos/metabolismo , Lentivirus/genética , Masculino , Mutação , Síndrome de Netherton/metabolismo , Síndrome de Netherton/patologia , Inibidor de Serinopeptidase do Tipo Kazal 5/genética , Inibidor de Serinopeptidase do Tipo Kazal 5/metabolismo , Resultado do Tratamento , Adulto Jovem
15.
Dig Liver Dis ; 51(11): 1537-1546, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31358484

RESUMO

BACKGROUND: Blue Rubber Bleb Nevus Syndrome (BRBNS) is a rare, severe, sporadically occurring disorder characterized by multiple venous malformations. AIMS: To present and analyze a case series of pediatric patients with BRBNS and to describe diagnostic approaches and management options applied. PATIENTS AND METHODS: Multicenter, retrospective study, evaluating the diagnosis and management of children with BRBNS. RESULTS: Eighteen patients diagnosed with BRBNS were included. Cutaneous venous malformations were observed in 78% and gastrointestinal venous malformations in 89%. Lesions were also found in other organs including muscles, joints, central nervous system, eyes, parotid gland, spine, kidneys and lungs. Gastrointestinal lesions were more common in the small intestine than in stomach or colon. The management varied significantly among centers. Endoscopic therapy and surgical therapy alone failed to prevent recurrence of lesions. In younger children and in patients with musculoskeletal or other organ involvement, sirolimus was used with 100% success rate in our series (5 patients treated) although poor compliance with subtherapeutic sirolimus trough levels led to recurrence in a minority. CONCLUSIONS: Considering the multi-organ involvement in BRBNS, diagnosis and management requires a multidisciplinary approach. The treatment includes conservative, medical, endoscopic and surgical options. Prospective multicenter studies are needed to identify the optimal management of this rare condition.


Assuntos
Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/terapia , Nevo Azul/diagnóstico , Nevo Azul/terapia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Criança , Pré-Escolar , Diagnóstico Diferencial , Endoscopia do Sistema Digestório , Feminino , Humanos , Lactente , Comunicação Interdisciplinar , Masculino , Recidiva Local de Neoplasia , Estudos Retrospectivos , Escleroterapia , Sirolimo/uso terapêutico , Malformações Vasculares/diagnóstico , Malformações Vasculares/terapia
16.
PLoS One ; 13(11): e0207412, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30427919

RESUMO

Alien chromosome introgression is used for the transfer of beneficial traits in plant breeding. For temperate forage grasses, much of the work in this context has focused on species within the ryegrasses (Lolium spp.) and the closely related fescues (Festuca spp.) particularly with a view to combining high forage quality with reliability and enhanced environmental services. We have analysed a L. perenne (perennial ryegrass) population containing the majority of a F. pratensis (meadow fescue) genome as introgressed chromosome segments to identify a) marker-trait associations for nutrient use and abiotic stress response across the family, and b) to assess the effects of introgression of F. pratensis genomic regions on phenotype. Using container-based assays and a system of flowing solution culture, we looked at phenotype responses, including root growth, to nitrogen and phosphorus status in the growing medium and abiotic stresses within this festulolium family. A number of significant marker/trait associations were identified across the family for root biomass on chromosomes 2, 3 and 5 and for heading date on chromosome 2. Of particular interest was a region on chromosome 2 associated with increased root biomass in phosphorus-limited conditions derived from one of the L. perenne parents. A genotype containing F. pratensis chromosome 4 as a monosomic introgression showed increased tiller number, shoot and root growth and genotypes with F. pratensis chromosome segment introgressions at different ends of chromosome 4 exhibited differential phenotypes across a variety of test conditions. There was also a general negative correlation between the extent of the F. pratensis genome that had been introgressed and root-related trait performances. We conclude that 1) the identification of alleles affecting root growth has potential application in forage grass breeding and, 2) F. pratensis introgressions can enhance quantitative traits, however, introgression can also have more general negative effects.


Assuntos
Cromossomos de Plantas/genética , Festuca/genética , Lolium/genética , Raízes de Plantas/genética , Festuca/crescimento & desenvolvimento , Estudos de Associação Genética , Genoma de Planta/genética , Lolium/crescimento & desenvolvimento , Melhoramento Vegetal , Raízes de Plantas/crescimento & desenvolvimento , Poaceae/genética
17.
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
18.
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
19.
Cardiovasc Intervent Radiol ; 41(3): 509-512, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29075882

RESUMO

Pressure-injectable peripherally inserted central catheters are now widely used for contrast pressure injections for CT scans. While they are generally regarded as safe, they are not free from complication. In this case review, we present three cases of PICC tips migrating post-CT contrast pressure injection including into the pleural cavity and subsequent complications, to raise awareness of this complication not previously encountered in our institution. Level of Evidence Level 4, Case Series.


Assuntos
Cateterismo Periférico/efeitos adversos , Meios de Contraste/administração & dosagem , Migração de Corpo Estranho/diagnóstico por imagem , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Lesões do Sistema Vascular/etiologia , Cateterismo Periférico/instrumentação , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico por imagem , Migração de Corpo Estranho/complicações , Humanos , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Mediastino/diagnóstico por imagem , Mediastino/lesões , Cavidade Pleural/diagnóstico por imagem , Cavidade Pleural/lesões , Pressão , Intensificação de Imagem Radiográfica/métodos , Lesões do Sistema Vascular/diagnóstico por imagem , Veia Cava Superior/diagnóstico por imagem
20.
Food Energy Secur ; 7(4): e00145, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30774947

RESUMO

The incorporation of new sophisticated phenotyping technologies within a crop improvement program allows for a plant breeding strategy that can include selections for major root traits previously inaccessible due to the challenges in their phenotype assessment. High-throughput precision phenotyping technology is employed to evaluate root ontogeny and progressive changes to root architecture of both novel amphiploid and introgression lines of Festulolium over four consecutive months of the growing season and these compared under the same time frame to that of closely related perennial ryegrass (L. perenne) varieties. Root imaging using conventional photography and assembled multiple merged images was used to compare frequencies in root number, their distribution within 0-20 and 20-40 cm depths within soil columns, and progressive changes over time. The Festulolium hybrids had more extensive root systems in comparison with L. perenne, and this was especially evident at depth. It was shown that the acquisition of extensive root systems in Festulolium hybrids was not dependent on the presence of an entire Festuca genome. On the contrary, the most pronounced effect on root development within the four Festulolium populations studied was observed in the introgression line Bx509, where a single small genome sequence from F. arundinacea had been previously transferred onto its homoeologous site on the long arm of chromosome 3 of an otherwise complete L. perenne genome. This demonstrates that a targeted introgression-breeding approach may be sufficient to confer a significant improvement in the root morphology in Lolium without a significant compromise to its genome integrity. The forage production of Bx509 was either higher (months 1-3) or equivalent to (month 4) that of its L. perenne parent control demonstrating that the enhanced root development achieved by the introgression line was without compromise to its agronomic performance.

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