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1.
Microorganisms ; 11(11)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38004729

RESUMO

Due to cryptic diversification, phenotypic plasticity and host associations, multilocus phylogenetic analyses have become the most important tool in accurately identifying and circumscribing species in the Diaporthe genus. However, the application of the genealogical concordance criterion has often been overlooked, ultimately leading to an exponential increase in novel Diaporthe spp. Due to the large number of species, many lineages remain poorly understood under the so-called species complexes. For this reason, a robust delimitation of the species boundaries in Diaporthe is still an ongoing challenge. Therefore, the present study aimed to resolve the species boundaries of the Diaporthe arecae species complex (DASC) by implementing an integrative taxonomic approach. The Genealogical Phylogenetic Species Recognition (GCPSR) principle revealed incongruences between the individual gene genealogies. Moreover, the Poisson Tree Processes' (PTPs) coalescent-based species delimitation models identified three well-delimited subclades represented by the species D. arecae, D. chiangmaiensis and D. smilacicola. These results evidence that all species previously described in the D. arecae subclade are conspecific, which is coherent with the morphological indistinctiveness observed and the absence of reproductive isolation and barriers to gene flow. Thus, 52 Diaporthe spp. are reduced to synonymy under D. arecae. Recent population expansion and the possibility of incomplete lineage sorting suggested that the D. arecae subclade may be considered as ongoing evolving lineages under active divergence and speciation. Hence, the genetic diversity and intraspecific variability of D. arecae in the context of current global climate change and the role of D. arecae as a pathogen on palm trees and other hosts are also discussed. This study illustrates that species in Diaporthe are highly overestimated, and highlights the relevance of applying an integrative taxonomic approach to accurately circumscribe the species boundaries in the genus Diaporthe.

2.
Pharm Stat ; 22(2): 408-413, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36450658

RESUMO

The intention of this article is to highlight sources of web-based reference material and software that will aid consulting statisticians when designing clinical trials. The article includes websites that provide links to explanation of statistical concepts for non-statisticians, regulatory guidelines, and free statistical study design software.


Assuntos
Consultores , Indústria Farmacêutica , Internet , Software , Humanos , Projetos de Pesquisa
3.
J Fungi (Basel) ; 7(6)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208444

RESUMO

The Karst landform is the main geographic characteristic in South China. Such areas are rich in vegetation and especially suitable for growth of shrubs and herbaceous plants. In this study, 11 Septoria strains were obtained from different plants' leaves collected in the Kunming Botanical Garden, Yunnan Province, China. Based on single-gene and multi-gene analyses of five gene loci (tef1, rpb2, tub2, ITS, and LSU) and four gene regions (without LSU), these strains were found to belong to three independent phylogenetic lineages representing five species, including four novel taxa, and one new record for China. Five single gene trees were also provided to evaluate the effectiveness of each gene for discriminating the species, as a result of which tub2 was found to have the most suitable DNA barcode for rapid identification. Morphological descriptions, illustrations, and comparisons are provided for a more comprehensive assessment. Genealogical Concordance Phylogenetic Species Recognition (GCPSR) with a pairwise homoplasy index (PHI) test was used to evaluate the conclusions of the phylogenetic analyses.

4.
Pharm Stat ; 16(1): 6-11, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26997517

RESUMO

ICH E9 Statistical Principles for Clinical Trials was issued in 1998. In October 2014, an addendum to ICH E9 was proposed relating to estimands and sensitivity analyses. In preparation for the release of the addendum, Statisticians in the Pharmaceutical Industry held a 1-day expert group meeting in February 2015. Topics debated included definition, development, implementation, education and communication challenges associated with estimands and sensitivity analyses. The topic of estimands is an important and relatively new one in clinical development. A clear message from the meeting was that estimands bridge the gap between study objectives and statistical methods. When defining estimands, an iterative process linking trial objectives, estimands, trial design, statistical and sensitivity analysis needs to be established. Each objective should have at least one distinct estimand, supported by sensitivity analyses. Because clinical trials are multi-faceted and expensive, it is unrealistic to restrict a study to a single objective and associated estimand. The actual set of estimands and sensitivity analyses for a study will depend on the study objectives, the disease setting and the needs of the various stakeholders. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Ensaios Clínicos como Assunto/métodos , Indústria Farmacêutica/métodos , Modelos Estatísticos , Projetos de Pesquisa , Interpretação Estatística de Dados , Desenho de Fármacos , Humanos
5.
J Pediatr Gastroenterol Nutr ; 59(2): 274-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24796801

RESUMO

Children comprise one-fifth of Europe's population. Promoting child health and development is of key importance for society and its future. This position paper highlights opportunities of investing in gastrointestinal, liver, and nutritional research to promote child health and delineates priorities for research. Investing in child health plays a key role in the promotion of population health, well-being, and disease prevention lifelong, with large health economic benefits. Major opportunities for improving knowledge and translational application arise from recent scientific and technological developments, for example, the long-term impact of early environmental cues interacting with genes. Personalised approaches to therapy and prevention should be enhanced. Deciphering the microbiome and its effects on functions can help in promoting long-term health. Epigenetic research can help to understand how early environmental factors influence later gastrointestinal and hepatic health and disease. A linked nutrition and physical activity strategy can promote health and prevent nutritional deficiencies, inactivity, and chronic noncommunicable diseases, such as diabetes, to ensure optimal health and cognition. Special attention should be devoted to populations with low socioeconomic status, migrant background, and ethnic minorities, and to critical life periods, including pregnancy, lactation, infancy, and childhood. Improved understanding of optimal nutrition and on maintaining gut and liver homeostasis throughout childhood will help prevent chronic diseases in later life.


Assuntos
Dieta , Trato Gastrointestinal , Promoção da Saúde , Fígado , Estado Nutricional , Pediatria , Pesquisa , Criança , Epigênese Genética , Europa (Continente) , Exercício Físico , Feminino , Gastroenterologia , Humanos , Lactente , Microbiota , Ciências da Nutrição , Gravidez , Fatores Socioeconômicos
6.
J Pediatr Gastroenterol Nutr ; 58(4): 525-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24399212

RESUMO

This position statement summarises a view of academia regarding standards for clinical research in collaboration with commercial enterprises, focussing on trials in pregnant women, breast-feeding women, and children. It is based on a review of the available literature and an expert workshop cosponsored by the Early Nutrition Academy and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition. Clinical research collaborations between academic investigators and commercial enterprises are encouraged by universities, public funding agencies, and governmental organisations. One reason is a pressing need to obtain evidence on the effects, safety, and benefits of drugs and other commercial products and services. The credibility and value of results obtained through public-private research collaborations have, however, been questioned because many examples of inappropriate research practice have become known. Clinical research in pregnant and breast-feeding women, and in infants and children, raises sensitive scientific, ethical, and societal questions and requires the application of particularly high standards. Here we provide recommendations for the conduct of public-private research collaborations in these populations. In the interest of all stakeholders, these recommendations should contribute to more reliable, credible, and acceptable results of commercially sponsored trials and to reducing the existing credibility gap.


Assuntos
Pesquisa Biomédica/ética , Pesquisa Biomédica/normas , Parcerias Público-Privadas/ética , Parcerias Público-Privadas/normas , Aleitamento Materno , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Indústria Farmacêutica , Feminino , Humanos , Lactente , Gravidez , Universidades
7.
Pharm Stat ; 12(5): 255-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23893876

RESUMO

In May 2012, the Committee of Health and Medicinal Products issued a concept paper on the need to review the points to consider document on multiplicity issues in clinical trials. In preparation for the release of the updated guidance document, Statisticians in the Pharmaceutical Industry held a one-day expert group meeting in January 2013. Topics debated included multiplicity and the drug development process, the usefulness and limitations of newly developed strategies to deal with multiplicity, multiplicity issues arising from interim decisions and multiregional development, and the need for simultaneous confidence intervals (CIs) corresponding to multiple test procedures. A clear message from the meeting was that multiplicity adjustments need to be considered when the intention is to make a formal statement about efficacy or safety based on hypothesis tests. Statisticians have a key role when designing studies to assess what adjustment really means in the context of the research being conducted. More thought during the planning phase needs to be given to multiplicity adjustments for secondary endpoints given these are increasing in importance in differentiating products in the market place. No consensus was reached on the role of simultaneous CIs in the context of superiority trials. It was argued that unadjusted intervals should be employed as the primary purpose of the intervals is estimation, while the purpose of hypothesis testing is to formally establish an effect. The opposing view was that CIs should correspond to the test decision whenever possible.


Assuntos
Indústria Farmacêutica/estatística & dados numéricos , Projetos de Pesquisa/estatística & dados numéricos , Pesquisadores , Ensaios Clínicos como Assunto/estatística & dados numéricos , Intervalos de Confiança , Humanos
8.
Pharm Stat ; 9(4): 288-97, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19844946

RESUMO

The Points to Consider Document on Missing Data was adopted by the Committee of Health and Medicinal Products (CHMP) in December 2001. In September 2007 the CHMP issued a recommendation to review the document, with particular emphasis on summarizing and critically appraising the pattern of drop-outs, explaining the role and limitations of the 'last observation carried forward' method and describing the CHMP's cautionary stance on the use of mixed models. In preparation for the release of the updated guidance document, statisticians in the Pharmaceutical Industry held a one-day expert group meeting in September 2008. Topics that were debated included minimizing the extent of missing data and understanding the missing data mechanism, defining the principles for handling missing data and understanding the assumptions underlying different analysis methods. A clear message from the meeting was that at present, biostatisticians tend only to react to missing data. Limited pro-active planning is undertaken when designing clinical trials. Missing data mechanisms for a trial need to be considered during the planning phase and the impact on the objectives assessed. Another area for improvement is in the understanding of the pattern of missing data observed during a trial and thus the missing data mechanism via the plotting of data; for example, use of Kaplan-Meier curves looking at time to withdrawal.


Assuntos
Ensaios Clínicos como Assunto/normas , Indústria Farmacêutica/normas , Guias de Prática Clínica como Assunto/normas , Humanos , Projetos de Pesquisa/normas
9.
Stat Med ; 22(1): 1-11; discussion 13-7, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12486747

RESUMO

The International Conference on Harmonization (ICH) E9 guideline 'Statistical principles for clinical trials' was adopted by the Committee for Proprietary Medicinal Products in March 1998, and consequently is operational in Europe. It has also been adopted in the U.S.A. and Japan. The aim of this paper is to relate the problems encountered during a recent regulatory submission to those discussed in the ICH E9 guideline. Statistical principles discussed in the guideline, but not comprehensively addressed when the clinical development programme was initiated in the mid-1990s, will be reviewed. The impact of each issue on the approvability of the dossier will be discussed, together with recommendations on how to avoid such problems with other ongoing clinical development programmes.


Assuntos
Interpretação Estatística de Dados , Guias como Assunto/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Aprovação de Drogas/métodos , Indústria Farmacêutica/legislação & jurisprudência , União Europeia , Humanos , Japão , Legislação de Medicamentos/normas , Preparações Farmacêuticas/normas , Estados Unidos
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