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1.
Nature ; 602(7896): 280-286, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34937943

RESUMO

Grafting is possible in both animals and plants. Although in animals the process requires surgery and is often associated with rejection of non-self, in plants grafting is widespread, and has been used since antiquity for crop improvement1. However, in the monocotyledons, which represent the second largest group of terrestrial plants and include many staple crops, the absence of vascular cambium is thought to preclude grafting2. Here we show that the embryonic hypocotyl allows intra- and inter-specific grafting in all three monocotyledon groups: the commelinids, lilioids and alismatids. We show functional graft unions through histology, application of exogenous fluorescent dyes, complementation assays for movement of endogenous hormones, and growth of plants to maturity. Expression profiling identifies genes that unify the molecular response associated with grafting in monocotyledons and dicotyledons, but also gene families that have not previously been associated with tissue union. Fusion of susceptible wheat scions to oat rootstocks confers resistance to the soil-borne pathogen Gaeumannomyces graminis. Collectively, these data overturn the consensus that monocotyledons cannot form graft unions, and identify the hypocotyl (mesocotyl in grasses) as a meristematic tissue that allows this process. We conclude that graft compatibility is a shared ability among seed-bearing plants.


Assuntos
Avena , Raízes de Plantas , Brotos de Planta , Transplantes , Triticum , Ascomicetos/patogenicidade , Avena/embriologia , Avena/microbiologia , Hipocótilo , Meristema , Raízes de Plantas/embriologia , Raízes de Plantas/microbiologia , Brotos de Planta/embriologia , Brotos de Planta/microbiologia , Triticum/embriologia , Triticum/microbiologia
2.
Proc Natl Acad Sci U S A ; 121(30): e2318982121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012828

RESUMO

The mutualistic arbuscular mycorrhizal (AM) symbiosis arose in land plants more than 450 million years ago and is still widely found in all major land plant lineages. Despite its broad taxonomic distribution, little is known about the molecular components underpinning symbiosis outside of flowering plants. The ARBUSCULAR RECEPTOR-LIKE KINASE (ARK) is required for sustaining AM symbiosis in distantly related angiosperms. Here, we demonstrate that ARK has an equivalent role in symbiosis maintenance in the bryophyte Marchantia paleacea and is part of a broad AM genetic program conserved among land plants. In addition, our comparative transcriptome analysis identified evolutionarily conserved expression patterns for several genes in the core symbiotic program required for presymbiotic signaling, intracellular colonization, and nutrient exchange. This study provides insights into the molecular pathways that consistently associate with AM symbiosis across land plants and identifies an ancestral role for ARK in governing symbiotic balance.


Assuntos
Embriófitas , Regulação da Expressão Gênica de Plantas , Micorrizas , Proteínas de Plantas , Simbiose , Simbiose/genética , Micorrizas/fisiologia , Micorrizas/genética , Embriófitas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Marchantia/genética , Marchantia/microbiologia , Filogenia
3.
Genet Med ; 26(7): 101144, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38641994

RESUMO

PURPOSE: GM1 gangliosidosis (GM1) a lysosomal disorder caused by pathogenic variants in GLB1, is characterized by relentless neurodegeneration. There are no approved treatments. METHODS: Forty-one individuals with type II (late-infantile and juvenile) GM1 participated in a single-site prospective observational study. RESULTS: Classification of 37 distinct variants using American College of Medical Genetics and Genomics criteria resulted in the upgrade of 6 and the submission of 4 new variants. In contrast to type I infantile disease, children with type II had normal or near normal hearing and did not have cherry-red maculae or hepatosplenomegaly. Some older children with juvenile onset disease developed thickened aortic and/or mitral valves. Serial magnetic resonance images demonstrated progressive brain atrophy, more pronounced in late infantile patients. Magnetic resonance spectroscopy showed worsening elevation of myo-inositol and deficit of N-acetyl aspartate that were strongly correlated with scores on the Vineland Adaptive Behavior Scale, progressing more rapidly in late infantile compared with juvenile onset disease. CONCLUSION: Serial phenotyping of type II GM1 patients expands the understanding of disease progression and clarifies common misconceptions about type II patients; these are pivotal steps toward more timely diagnosis and better supportive care. The data amassed through this 10-year effort will serve as a robust comparator for ongoing and future therapeutic trials.


Assuntos
Gangliosidose GM1 , Imageamento por Ressonância Magnética , Humanos , Gangliosidose GM1/genética , Gangliosidose GM1/patologia , Feminino , Masculino , Estudos Prospectivos , Pré-Escolar , Criança , Lactente , Adolescente , Fenótipo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Mutação , Progressão da Doença , Adulto , beta-Galactosidase
4.
BJOG ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659133

RESUMO

OBJECTIVE: To compare the cost-effectiveness of different treatments for cervical intraepithelial neoplasia (CIN). DESIGN: A cost-effectiveness analysis based on data available in the literature and expert opinion. SETTING: England. POPULATION: Women treated for CIN. METHODS: We developed a decision-analytic model to simulate the clinical course of 1000 women who received local treatment for CIN and were followed up for 10 years after treatment. In the model we considered surgical complications as well as oncological and reproductive outcomes over the 10-year period. The costs calculated were those incurred by the National Health Service (NHS) of England. MAIN OUTCOME MEASURES: Cost per one CIN2+ recurrence averted (oncological outcome); cost per one preterm birth averted (reproductive outcome); overall cost per one adverse oncological or reproductive outcome averted. RESULTS: For young women of reproductive age, large loop excision of the transformation zone (LLETZ) was the most cost-effective treatment overall at all willingness-to-pay thresholds. For postmenopausal women, LLETZ remained the most cost-effective treatment up to a threshold of £31,500, but laser conisation became the most cost-effective treatment above that threshold. CONCLUSIONS: LLETZ is the most cost-effective treatment for both younger and older women. However, for older women, more radical excision with laser conisation could also be considered if the NHS is willing to spend more than £31,500 to avert one CIN2+ recurrence.

5.
BMC Med ; 21(1): 274, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37501128

RESUMO

BACKGROUND: Persistent infection by oncogenic human papillomavirus (HPV) is necessary although not sufficient for development of cervical cancer. Behavioural, environmental, or comorbid exposures may promote or protect against malignant transformation. Randomised evidence is limited and the validity of observational studies describing these associations remains unclear. METHODS: In this umbrella review, we searched electronic databases to identify meta-analyses of observational studies that evaluated risk or protective factors and the incidence of HPV infection, cervical intra-epithelial neoplasia (CIN), cervical cancer incidence and mortality. Following re-analysis, evidence was classified and graded based on a pre-defined set of statistical criteria. Quality was assessed with AMSTAR-2. For all associations graded as weak evidence or above, with available genetic instruments, we also performed Mendelian randomisation to examine the potential causal effect of modifiable exposures with risk of cervical cancer. The protocol for this study was registered on PROSPERO (CRD42020189995). RESULTS: We included 171 meta-analyses of different exposure contrasts from 50 studies. Systemic immunosuppression including HIV infection (RR = 2.20 (95% CI = 1.89-2.54)) and immunosuppressive medications for inflammatory bowel disease (RR = 1.33 (95% CI = 1.27-1.39)), as well as an altered vaginal microbiome (RR = 1.59 (95% CI = 1.40-1.81)), were supported by strong and highly suggestive evidence for an association with HPV persistence, CIN or cervical cancer. Smoking, number of sexual partners and young age at first pregnancy were supported by highly suggestive evidence and confirmed by Mendelian randomisation. CONCLUSIONS: Our main analysis supported the association of systemic (HIV infection, immunosuppressive medications) and local immunosuppression (altered vaginal microbiota) with increased risk for worse HPV and cervical disease outcomes. Mendelian randomisation confirmed the link for genetically predicted lifetime smoking index, and young age at first pregnancy with cervical cancer, highlighting also that observational evidence can hide different inherent biases. This evidence strengthens the need for more frequent HPV screening in people with immunosuppression, further investigation of the vaginal microbiome and access to sexual health services.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Gravidez , Seguimentos , Infecções por HIV/complicações , Papillomavirus Humano , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/genética , Fatores de Risco , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/diagnóstico , Análise da Randomização Mendeliana
6.
Proc Natl Acad Sci U S A ; 117(13): 7338-7346, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32179675

RESUMO

Clearance of surgical margins in cervical cancer prevents the need for adjuvant chemoradiation and allows fertility preservation. In this study, we determined the capacity of the rapid evaporative ionization mass spectrometry (REIMS), also known as intelligent knife (iKnife), to discriminate between healthy, preinvasive, and invasive cervical tissue. Cervical tissue samples were collected from women with healthy, human papilloma virus (HPV) ± cervical intraepithelial neoplasia (CIN), or cervical cancer. A handheld diathermy device generated surgical aerosol, which was transferred into a mass spectrometer for subsequent chemical analysis. Combination of principal component and linear discriminant analysis and least absolute shrinkage and selection operator was employed to study the spectral differences between groups. Significance of discriminatory m/z features was tested using univariate statistics and tandem MS performed to elucidate the structure of the significant peaks allowing separation of the two classes. We analyzed 87 samples (normal = 16, HPV ± CIN = 50, cancer = 21 patients). The iKnife discriminated with 100% accuracy normal (100%) vs. HPV ± CIN (100%) vs. cancer (100%) when compared to histology as the gold standard. When comparing normal vs. cancer samples, the accuracy was 100% with a sensitivity of 100% (95% CI 83.9 to 100) and specificity 100% (79.4 to 100). Univariate analysis revealed significant MS peaks in the cancer-to-normal separation belonging to various classes of complex lipids. The iKnife discriminates healthy from premalignant and invasive cervical lesions with high accuracy and can improve oncological outcomes and fertility preservation of women treated surgically for cervical cancer. Larger in vivo research cohorts are required to validate these findings.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Análise Discriminante , Feminino , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Margens de Excisão , Pessoa de Meia-Idade , Papillomaviridae , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/cirurgia , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/cirurgia , Displasia do Colo do Útero
7.
Lancet Oncol ; 23(8): 1097-1108, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35835138

RESUMO

BACKGROUND: The trade-off between comparative effectiveness and reproductive morbidity of different treatment methods for cervical intraepithelial neoplasia (CIN) remains unclear. We aimed to determine the risks of treatment failure and preterm birth associated with various treatment techniques. METHODS: In this systematic review and network meta-analysis, we searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials database for randomised and non-randomised studies reporting on oncological or reproductive outcomes after CIN treatments from database inception until March 9, 2022, without language restrictions. We included studies of women with CIN, glandular intraepithelial neoplasia, or stage IA1 cervical cancer treated with excision (cold knife conisation [CKC], laser conisation, and large loop excision of the transformation zone [LLETZ]) or ablation (radical diathermy, laser ablation, cold coagulation, and cryotherapy). We excluded women treated with hysterectomy. The primary outcomes were any treatment failure (defined as any abnormal histology or cytology) and preterm birth (<37 weeks of gestation). The network for preterm birth also included women with untreated CIN (untreated colposcopy group). The main reference group was LLETZ for treatment failure and the untreated colposcopy group for preterm birth. For randomised controlled trials, we extracted group-level summary data, and for observational studies, we extracted relative treatment effect estimates adjusted for potential confounders, when available, and we did random-effects network meta-analyses to obtain odds ratios (ORs) with 95% CIs. We assessed within-study and across-study risk of bias using Cochrane tools. This systematic review is registered with PROSPERO, CRD42018115495 and CRD42018115508. FINDINGS: 7880 potential citations were identified for the outcome of treatment failure and 4107 for the outcome of preterm birth. After screening and removal of duplicates, the network for treatment failure included 19 240 participants across 71 studies (25 randomised) and the network for preterm birth included 68 817 participants across 29 studies (two randomised). Compared with LLETZ, risk of treatment failure was reduced for other excisional methods (laser conisation: OR 0·59 [95% CI 0·44-0·79] and CKC: 0·63 [0·50-0·81]) and increased for laser ablation (1·69 [1·27-2·24]) and cryotherapy (1·84 [1·33-2·56]). No differences were found for the comparison of cold coagulation versus LLETZ (1·09 [0·68-1·74]) but direct data were based on two small studies only. Compared with the untreated colposcopy group, risk of preterm birth was increased for all excisional techniques (CKC: 2·27 [1·70-3·02]; laser conisation: 1·77 [1·29-2·43]; and LLETZ: 1·37 [1·16-1·62]), whereas no differences were found for ablative methods (laser ablation: 1·05 [0·78-1·41]; cryotherapy: 1·01 [0·35-2·92]; and cold coagulation: 0·67 [0·02-29·15]). The evidence was based mostly on observational studies with their inherent risks of bias, and the credibility of many comparisons was low. INTERPRETATION: More radical excisional techniques reduce the risk of treatment failure but increase the risk of subsequent preterm birth. Although there is uncertainty, ablative treatments probably do not increase risk of preterm birth, but are associated with higher failure rates than excisional techniques. Although we found LLETZ to have balanced effectiveness and reproductive morbidity, treatment choice should rely on a woman's age, size and location of lesion, and future family planning. FUNDING: National Institute for Health and Care Research: Research for Patient Benefit.


Assuntos
Nascimento Prematuro , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Conização/efeitos adversos , Conização/métodos , Feminino , Humanos , Recém-Nascido , Metanálise em Rede , Nascimento Prematuro/epidemiologia , Neoplasias do Colo do Útero/cirurgia , Displasia do Colo do Útero/cirurgia
8.
BMC Med ; 20(1): 254, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35945610

RESUMO

Adaptive designs are a class of methods for improving efficiency and patient benefit of clinical trials. Although their use has increased in recent years, research suggests they are not used in many situations where they have potential to bring benefit. One barrier to their more widespread use is a lack of understanding about how the choice to use an adaptive design, rather than a traditional design, affects resources (staff and non-staff) required to set-up, conduct and report a trial. The Costing Adaptive Trials project investigated this issue using quantitative and qualitative research amongst UK Clinical Trials Units. Here, we present guidance that is informed by our research, on considering the appropriate resourcing of adaptive trials. We outline a five-step process to estimate the resources required and provide an accompanying costing tool. The process involves understanding the tasks required to undertake a trial, and how the adaptive design affects them. We identify barriers in the publicly funded landscape and provide recommendations to trial funders that would address them. Although our guidance and recommendations are most relevant to UK non-commercial trials, many aspects are relevant more widely.


Assuntos
Projetos de Pesquisa , Humanos
9.
Br J Dermatol ; 187(3): 324-337, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34988975

RESUMO

BACKGROUND: The risk of cutaneous squamous cell carcinoma (cSCC) is significantly increased in organ transplant recipients (OTRs). Clearance of actinic keratoses (AKs) is generally regarded as a surrogate biomarker for cSCC prevention. OTR-cSCC chemoprevention with topical AK treatments has not been investigated in randomized controlled trials (RCTs), although there is evidence that 5% 5-fluorouracil (5-FU) may be chemoprotective in immunocompetent patients. OBJECTIVES: To assess the feasibility, activity and evaluation outcomes relevant to the design of a future phase III RCT of topical cSCC chemoprevention in OTRs. METHODS: OTRs with 10 or more AKs in predefined areas were randomized 1 : 1 : 1 to topical 5-FU, 5% imiquimod (IMIQ) or sunscreen (sun-protective factor 30+) in a phase II, open-label RCT over 15 months. Feasibility outcomes included proportions of eligible OTRs randomized, completing treatment and willing to be re-treated. AK activity [AK clearance, new AK development, patient-centred outcomes (toxicity, health-related quality of life, HRQoL)] and evaluation methodology (clinical vs. photographic) were assessed. RESULTS: Forty OTRs with 903 AKs were randomized. All feasibility outcomes were met (56% of eligible OTRs were randomized; 89% completed treatment; 81% were willing to be re-treated). AK activity analyses found 5-FU and IMIQ were superior to sunscreen for AK clearance and prevention of new AKs. 5-FU was more effective than IMIQ in AK clearance and prevention in exploratory analyses. Although toxicity was greater with 5-FU, HRQoL outcomes were similar. CONCLUSIONS: Trials of topical AK treatments in OTRs for cSCC chemoprevention are feasible and AK activity results support further investigation of 5-FU-based treatments in future phase III trials. What is already known about this topic? Cutaneous squamous cell carcinoma (cSCC) is significantly more common in immunocompromised individuals including organ transplant recipients (OTRs) compared with immunocompetent populations. cSCC chemoprevention activity of sunscreen and 5-fluorouracil-based (5-FU) actinic keratosis (AK) treatments has been demonstrated in randomized controlled trials (RCTs) in immunocompetent populations but not in OTRs. AKs are cSCC precursors and their clearance and prevention are generally regarded as surrogate endpoint biomarkers for potential cSCC chemoprevention activity. What does this study add? SPOT (SCC Prevention in OTRs using Topical treatments) has confirmed that RCTs of OTR-cSCC chemoprevention with topical AK treatments are feasible. It also suggests that topical 5-FU may be superior to 5% imiquimod and sunscreen in AK clearance and prevention. Together with recent evidence from several RCTs in the general population, these data provide a compelling rationale for further studies of intervention with 5-FU-based topical chemoprevention approaches in OTR-cSCC prevention.


Assuntos
Carcinoma de Células Escamosas , Ceratose Actínica , Transplante de Órgãos , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/prevenção & controle , Estudos de Viabilidade , Fluoruracila/uso terapêutico , Humanos , Imiquimode/uso terapêutico , Ceratose Actínica/tratamento farmacológico , Ceratose Actínica/patologia , Ceratose Actínica/prevenção & controle , Transplante de Órgãos/efeitos adversos , Protetores Solares/uso terapêutico , Transplantados , Resultado do Tratamento
10.
Lancet Oncol ; 22(4): 548-557, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33794208

RESUMO

BACKGROUND: Most uterine cervical high-risk human papillomavirus (HPV) infections are transient, with only a small fraction developing into cervical cancer. Family aggregation studies and heritability estimates suggest a significant inherited genetic component. Candidate gene studies and previous genome-wide association studies (GWASs) report associations between the HLA region and cervical cancer. Adopting a genome-wide approach, we aimed to compare genetic variation in women with invasive cervical cancer and cervical intraepithelial neoplasia (CIN) grade 3 with that in healthy controls. METHODS: We did a GWAS in a cohort of unrelated European individuals using data from UK Biobank, a population-based cohort including 273 377 women aged 40-69 years at recruitment between March 13, 2006, and Oct 1, 2010. We used an additive univariate logistic regression model to analyse genetic variants associated with invasive cervical cancer or CIN3. We sought replication of candidate associations in FinnGen, a large independent dataset of 128 123 individuals. We also did a two-sample mendelian randomisation approach to explore the role of risk factors in the genetic risk of cervical cancer. FINDINGS: We included 4769 CIN3 and invasive cervical cancer case samples and 145 545 control samples in the GWAS. Of 9 600 464 assayed and imputed single-nucleotide polymorphisms (SNPs), six independent variants were associated with CIN3 and invasive cervical cancer. These included novel loci rs10175462 (PAX8; odds ratio [OR] 0·87, 95% CI 0·84-0·91; p=1·07 × 10-9) and rs27069 (CLPTM1L; 0·88, 0·84-0·92; p=2·51 × 10-9), and previously reported signals at rs9272050 (HLA-DQA1; 1·27, 1·21-1·32; p=2·51 × 10-28), rs6938453 (MICA; 0·79, 0·75-0·83; p=1·97 × 10-17), rs55986091 (HLA-DQB1; 0·66, 0·60-0·72; p=6·42 × 10-28), and rs9266183 (HLA-B; 0·73, 0·64-0·83; p=1·53 × 10-6). Three SNPs were replicated in the independent Finnish dataset of 1648 invasive cervical cancer cases: PAX8 (rs10175462; p=0·015), CLPTM1L (rs27069; p=2·54 × 10-7), and HLA-DQA1 (rs9272050; p=7·90 × 10-8). Mendelian randomisation further supported the complementary role of smoking (OR 2·46, 95% CI 1·64-3·69), older age at first pregnancy (0·80, 0·68-0·95), and number of sexual partners (1·95, 1·44-2·63) in the risk of developing cervical cancer. INTERPRETATION: Our results provide new evidence for the genetic susceptibility to cervical cancer, specifically the PAX8, CLPTM1L, and HLA genes, suggesting disruption in apoptotic and immune function pathways. Future studies integrating host and viral, genetic, and epigenetic variation, could further elucidate complex host-viral interactions. FUNDING: NIHR Imperial BRC Wellcome 4i Clinician Scientist Training Programme.


Assuntos
Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Fator de Transcrição PAX8/genética , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Antígenos HLA/genética , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
11.
BMC Plant Biol ; 21(1): 524, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758742

RESUMO

BACKGROUND: Grain size is thought to be a major component of yield in many plant species. Here we set out to understand if knowledge from other cereals such as rice could translate to increased yield gains in wheat and lead to increased nitrogen use efficiency. Previous findings that the overexpression of OsBG1 in rice increased yields while increasing seed size suggest translating gains from rice to other cereals may help to increase yields. RESULTS: The orthologous genes of OsBG1 were identified in wheat. One homoeologous wheat gene was cloned and overexpressed in wheat to understand its role in controlling seed size. Potential alteration in the nutritional profile of the grains were also analyzed in wheat overexpressing TaBG1. It was found that increased TaBG1-A expression could indeed lead to larger seed size but was linked to a reduction in seed number per plant leading to no significant overall increase in yield. Other important components of yield such as biomass or tillering did not change significantly with increased TaBG1-A expression. The nutritional profile of the grain was altered, with a significant decrease in the Zn levels in the grain associated with increased seed size, but Fe and Mn concentrations were unchanged. Protein content of the wheat grain also fell under moderate N fertilization levels but not under deficient or adequate levels of N. CONCLUSIONS: TaBG1 does control seed size in wheat but increasing the seed size per se does not increase yield and may come at the cost of lower concentrations of essential elements as well as potentially lower protein content. Nevertheless, TaBG1 could be a useful target for further breeding efforts in combination with other genes for increased biomass.


Assuntos
Genes de Plantas , Sementes/genética , Triticum/genética , Biomassa , Grão Comestível/química , Grão Comestível/genética , Grão Comestível/metabolismo , Nitrogênio/metabolismo , Valor Nutritivo/genética , Plantas Geneticamente Modificadas , Sementes/anatomia & histologia , Sementes/química , Sementes/metabolismo , Triticum/anatomia & histologia , Triticum/química , Triticum/metabolismo
12.
BMC Med ; 19(1): 251, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34696781

RESUMO

BACKGROUND: Adaptive designs offer great promise in improving the efficiency and patient-benefit of clinical trials. An important barrier to further increased use is a lack of understanding about which additional resources are required to conduct a high-quality adaptive clinical trial, compared to a traditional fixed design. The Costing Adaptive Trials (CAT) project investigated which additional resources may be required to support adaptive trials. METHODS: We conducted a mock costing exercise amongst seven Clinical Trials Units (CTUs) in the UK. Five scenarios were developed, derived from funded clinical trials, where a non-adaptive version and an adaptive version were described. Each scenario represented a different type of adaptive design. CTU staff were asked to provide the costs and staff time they estimated would be needed to support the trial, categorised into specified areas (e.g. statistics, data management, trial management). This was calculated separately for the non-adaptive and adaptive version of the trial, allowing paired comparisons. Interviews with 10 CTU staff who had completed the costing exercise were conducted by qualitative researchers to explore reasons for similarities and differences. RESULTS: Estimated resources associated with conducting an adaptive trial were always (moderately) higher than for the non-adaptive equivalent. The median increase was between 2 and 4% for all scenarios, except for sample size re-estimation which was 26.5% (as the adaptive design could lead to a lengthened study period). The highest increase was for statistical staff, with lower increases for data management and trial management staff. The percentage increase in resources varied across different CTUs. The interviews identified possible explanations for differences, including (1) experience in adaptive trials, (2) the complexity of the non-adaptive and adaptive design, and (3) the extent of non-trial specific core infrastructure funding the CTU had. CONCLUSIONS: This work sheds light on additional resources required to adequately support a high-quality adaptive trial. The percentage increase in costs for supporting an adaptive trial was generally modest and should not be a barrier to adaptive designs being cost-effective to use in practice. Informed by the results of this research, guidance for investigators and funders will be developed on appropriately resourcing adaptive trials.


Assuntos
Projetos de Pesquisa , Pesquisadores , Análise Custo-Benefício , Humanos , Recursos Humanos
13.
PLoS Pathog ; 15(3): e1007620, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30856238

RESUMO

The biotrophic fungal pathogen Blumeria graminis causes the powdery mildew disease of cereals and grasses. We present the first crystal structure of a B. graminis effector of pathogenicity (CSEP0064/BEC1054), demonstrating it has a ribonuclease (RNase)-like fold. This effector is part of a group of RNase-like proteins (termed RALPHs) which comprise the largest set of secreted effector candidates within the B. graminis genomes. Their exceptional abundance suggests they play crucial functions during pathogenesis. We show that transgenic expression of RALPH CSEP0064/BEC1054 increases susceptibility to infection in both monocotyledonous and dicotyledonous plants. CSEP0064/BEC1054 interacts in planta with the pathogenesis-related protein PR10. The effector protein associates with total RNA and weakly with DNA. Methyl jasmonate (MeJA) levels modulate susceptibility to aniline-induced host RNA fragmentation. In planta expression of CSEP0064/BEC1054 reduces the formation of this RNA fragment. We propose CSEP0064/BEC1054 is a pseudoenzyme that binds to host ribosomes, thereby inhibiting the action of plant ribosome-inactivating proteins (RIPs) that would otherwise lead to host cell death, an unviable interaction and demise of the fungus.


Assuntos
Ascomicetos/patogenicidade , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Imunidade Vegetal/imunologia , Plantas/imunologia , RNA de Plantas/metabolismo , RNA Ribossômico/metabolismo , Sequência de Aminoácidos , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Plantas/microbiologia , Conformação Proteica , RNA de Plantas/genética , RNA Ribossômico/genética , Homologia de Sequência
14.
New Phytol ; 230(2): 629-640, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33124693

RESUMO

Wheat is the most widely grown crop globally, providing 20% of all human calories and protein. Achieving step changes in genetic yield potential is crucial to ensure food security, but efforts are thwarted by an apparent trade-off between grain size and number. Expansins are proteins that play important roles in plant growth by enhancing stress relaxation in the cell wall, which constrains cell expansion. Here, we describe how targeted overexpression of an α-expansin in early developing wheat seeds leads to a significant increase in grain size without a negative effect on grain number, resulting in a yield boost under field conditions. The best-performing transgenic line yielded 12.3% higher average grain weight than the control, and this translated to an increase in grain yield of 11.3% in field experiments using an agronomically appropriate plant density. This targeted transgenic approach provides an opportunity to overcome a common bottleneck to yield improvement across many crops.


Assuntos
Expressão Ectópica do Gene , Triticum , Produtos Agrícolas/metabolismo , Grão Comestível/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Triticum/genética , Triticum/metabolismo
15.
Am J Respir Crit Care Med ; 202(11): 1567-1575, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645277

RESUMO

Rationale: Most U.S. residents who develop tuberculosis (TB) were born abroad, and U.S. TB incidence is increasingly driven by infection risks in other countries.Objectives: To estimate the potential impact of effective global TB control on health and economic outcomes in the United States.Methods: We estimated outcomes using linked mathematical models of TB epidemiology in the United States and migrants' birth countries. A base-case scenario extrapolated country-specific TB incidence trends. We compared this with scenarios in which countries achieve 90% TB incidence reductions between 2015 and 2035, as targeted by the World Health Organization's End TB Strategy ("effective global TB control"). We also considered pessimistic scenarios of flat TB incidence trends in individual countries.Measurements and Main Results: We estimated TB cases, deaths, and costs and the total economic burden of TB in the United States. Compared with the base-case scenario, effective global TB control would avert 40,000 (95% uncertainty interval, 29,000-55,000) TB cases in the United States in 2020-2035. TB incidence rates in 2035 would be 43% (95% uncertainty interval, 34-54%) lower than in the base-case scenario, and 49% (95% uncertainty interval, 44-55%) lower than in 2020. Summed over 2020-2035, this represents 0.8 billion dollars (95% uncertainty interval, 0.6-1.0 billion dollars) in averted healthcare costs and $2.5 billion dollars (95% uncertainty interval, 1.7-3.6 billion dollars) in productivity gains. The total U.S. economic burden of TB (including the value of averted TB deaths) would be 21% (95% uncertainty interval, 16-28%) lower (18 billion dollars [95% uncertainty level, 8-32 billion dollars]).Conclusions: In addition to producing major health benefits for high-burden countries, strengthened efforts to achieve effective global TB control could produce substantial health and economic benefits for the United States.


Assuntos
Controle de Doenças Transmissíveis , Emigrantes e Imigrantes/estatística & dados numéricos , Saúde Global , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , China/epidemiologia , China/etnologia , Erradicação de Doenças , Custos de Cuidados de Saúde , Humanos , Incidência , Índia/epidemiologia , Índia/etnologia , México/epidemiologia , México/etnologia , Modelos Teóricos , Filipinas/epidemiologia , Filipinas/etnologia , Tuberculose/economia , Tuberculose/mortalidade , Estados Unidos/epidemiologia , Vietnã/epidemiologia , Vietnã/etnologia
16.
Int J Mol Sci ; 22(24)2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34948126

RESUMO

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a heritable renal disease that results in end-stage kidney disease, due to the uncontrolled bilateral growth of cysts throughout the kidneys. While it is known that a mutation within a PKD-causing gene is required for the development of ADPKD, the underlying mechanism(s) causing cystogenesis and progression of the disease are not well understood. Limited therapeutic options are currently available to slow the rate of cystic growth. Epigenetic modifications, including DNA methylation, are known to be altered in neoplasia, and several FDA-approved therapeutics target these disease-specific changes. As there are many similarities between ADPKD and neoplasia, we (and others) have postulated that ADPKD kidneys contain alterations to their epigenetic landscape that could be exploited for future therapeutic discovery. Here we summarise the current understanding of epigenetic changes that are associated with ADPKD, with a particular focus on the burgeoning field of ADPKD-specific alterations in DNA methylation.


Assuntos
Metilação de DNA , Epigênese Genética , Rim Policístico Autossômico Dominante , Animais , Modelos Animais de Doenças , Humanos , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo
18.
BMC Infect Dis ; 19(1): 1035, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805896

RESUMO

Following publication of the original article [1], one of the authors, Dr. Sarah E. Bowden reported that at the time of the study she wasn't working for the Division of Global Migration and Quarantine, Centers for Disease Control, 1600 Clifton Road, Atlanta, GA 30329-4027, USA.

19.
BMC Infect Dis ; 19(1): 861, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623574

RESUMO

BACKGROUND: Exposure to blacklegged ticks Ixodes scapularis that transmit pathogens is thought to occur peri-domestically. However, the locations where people most frequently encounter infected ticks are not well characterized, leading to mixed messages from public health officials about where risk is highest. METHODS: We conducted a systematic review and meta-analysis on spatial risk factors for tick-borne disease and tick bites in eastern North America. We examined three scales: the residential yard, the neighborhood surrounding (but not including) the yard, and outside the neighborhood. Nineteen eligible studies represented 2741 cases of tick-borne illness and 1447 tick bites. Using random effects models, we derived pooled odds ratio (OR) estimates. RESULTS: The meta-analysis revealed significant disease risk factors at the scale of the yard (OR 2.60 95% CI 1.96 - 3.46), the neighborhood (OR 4.08 95% CI 2.49 - 6.68), and outside the neighborhood (OR 2.03 95% CI 1.59 - 2.59). Although significant risk exists at each scale, neighborhood scale risk factors best explained disease exposure. Analysis of variance revealed risk at the neighborhood scale was 57% greater than risk at the yard scale and 101% greater than risk outside the neighborhood. CONCLUSIONS: This analysis emphasizes the importance of understanding and reducing tick-borne disease risk at the neighborhood scale. Risk-reducing interventions applied at each scale could be effective, but interventions applied at the neighborhood scale are most likely to protect human health. TRIAL REGISTRATION: The study was registered with PROSPERO: CRD42017079169 .


Assuntos
Picadas de Carrapatos/diagnóstico , Doenças Transmitidas por Carrapatos/diagnóstico , Animais , Humanos , Ixodes/fisiologia , Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , América do Norte/epidemiologia , Razão de Chances , Características de Residência/estatística & dados numéricos , Fatores de Risco , Picadas de Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia
20.
Int J Gynecol Cancer ; 29(8): 1292-1297, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31481452

RESUMO

INTRODUCTION: Splenectomy-induced thrombocytosis and leukocytosis may obscure the early diagnosis of post-operative infection or sepsis. In trauma patients after splenectomy, a platelet-to-white blood cell ratio of <20 has been shown to reliably differentiate post-operative sepsis from transient physiological responses. OBJECTIVE: To determine whether the platelet-to-white blood cell ratio can be applied to differentiate between reactive post-operative changes and latent infection. METHODS: All consecutive patients with ovarian cancer who underwent splenectomy between January 2013 and October 2018 in two large European gynecological cancer centers were retrospectively evaluated. Main outcome measures were white blood cell count, platelet count, and platelet-to-white blood cell ratio on post-operative days 1, 5, and 7. These were correlated with surgical outcome and morbidity according to the Clavien-Dindo classification. A binomial logistic regression was applied to assess the predictive value of day 5 platelet-to-white blood cell ratio, white blood cell count, and platelet count for predicting grade III post-operative sepsis. RESULTS: Ninety-five patients with ovarian cancer (mean age 54 years, range 18-75) were identified. Seventeen patients (17.9%) developed a grade III post-operative sepsis. In all post-operative patients, mean white blood cell count on day 5 decreased (from 15.4×103/µL to 11.4×103/µL), while the mean platelet count rose (from 260.7×103/µL to 385.3×103/µL). A high platelet count (>313×103/µL) failed to show any predictive value (OR=0.94; 95% CI 0.30 to 3.0; p=0.921). A low platelet-to-white blood cell ratio (<26) (OR=3.49; 95% CI 1.18 to 10.32; p=0.0241) and high white blood cell count (>14.5×103/µL) on day 5 (OR=11.0; 95% CI 3.3 to 36.2; p<0.001) were significant for predicting sepsis. Despite a significant OR, the sensitivity and specificity were low; day 5 platelet-to-white blood cell ratio at a cut-off point of 26 achieved a sensitivity of 72% and specificity of 53% (area under the curve 0.637, 95% CI 0.480 to 0.796) in predicting grade III post-operative sepsis. CONCLUSIONS: Platelet-to-white blood cell ratio after cytoreductive surgery for ovarian cancer with splenectomy does not appear to have a strong predictive value in differentiating between sepsis and reactive splenectomy-induced changes. Leukocytosis, in combination with clinical assessment, may remain the most useful tool for prediction of sepsis after cytoreductive surgery with splenectomy.


Assuntos
Plaquetas/patologia , Leucócitos/patologia , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/cirurgia , Sepse/sangue , Adolescente , Adulto , Idoso , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Procedimentos Cirúrgicos de Citorredução/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Sepse/etiologia , Esplenectomia/efeitos adversos , Esplenectomia/métodos , Adulto Jovem
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