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1.
J Exp Bot ; 67(14): 4209-20, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27217545

RESUMO

Salinity is a severe abiotic stress that affects irrigated croplands. Jasmonate (JA) is an essential hormone involved in plant defense against herbivory and in responses to abiotic stress. However, the relationship between the salt stress response and the JA pathway in Arabidopsis thaliana is not well understood at molecular and cellular levels. In this work we investigated the activation of JA signaling by NaCl and its effect on primary root growth. We found that JA-responsive JAZ genes were up-regulated by salt stress in a COI1-dependent manner in the roots. Using a JA-Ile sensor we demonstrated that activation of JA signaling by salt stress occurs in the meristematic zone and stele of the differentiation zone and that this activation was dependent on JAR1 and proteasome functions. Another finding is that the elongation zone (EZ) and its cortical cells were significantly longer in JA-related mutants (AOS, COI1, JAZ3 and MYC2/3/4 genes) compared with wild-type plants under salt stress, revealing the participation of the canonical JA signaling pathway. Noteworthy, osmotic stress - a component of salt stress - inhibited cell elongation in the EZ in a COI1-dependent manner. We propose that salt stress triggers activation of the JA signaling pathway followed by inhibition of cell elongation in the EZ. We have shown that salt-inhibited root growth partially involves the jasmonate signaling pathway in Arabidopsis.


Assuntos
Arabidopsis/fisiologia , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Tolerância ao Sal/fisiologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
2.
Endocr Relat Cancer ; 30(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37671897

RESUMO

Molecular testing contributes to improving the diagnosis of indeterminate thyroid nodules (ITNs). ThyroidPrint® is a ten-gene classifier aimed to rule out malignancy in ITN. Post-validation studies are necessary to determine the real-world clinical benefit of ThyroidPrint® in patients with ITN. A single-center, prospective, noninterventional clinical utility study was performed, analyzing the impact of ThyroidPrint® in the physicians' clinical decisions for ITN. Demographics, nodule characteristics, benign call rates (BCRs), and surgical outcomes were measured. Histopathological data were collected from surgical biopsies of resected nodules. Of 1272 fine-needle aspirations, 109 (8.6%) were Bethesda III and 135 (10.6%) were Bethesda IV. Molecular testing was performed in 155 of 244 ITN (63.5%), of which 104 were classified as benign (BCR of 67.1%). After a median follow-up of 15 months, 103 of 104 (99.0%) patients with a benign ThyroidPrint® remained under surveillance and one patient underwent surgery which was a follicular adenoma. Surgery was performed in all 51 patients with a suspicious for malignancy as per ThyroidPrint® result and in 56 patients who did not undergo testing, with a rate of malignancy of 70.6% and 32.1%, respectively. A higher BCR was observed in follicular lesion of undetermined significance (87%) compared to atypia of undetermined significance (58%) (P < 0.05). False-positive cases included four benign follicular nodules and six follicular and four oncocytic adenomas. Our results show that, physicians chose active surveillance instead of diagnostic surgery in all patients with a benign ThyroidPrint® result, reducing the need for diagnostic surgery in 67% of patients with preoperative diagnosis of ITN.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Estudos Prospectivos , Perfilação da Expressão Gênica/métodos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/cirurgia , Biópsia por Agulha Fina
3.
Med Ref Serv Q ; 29(2): 132-45, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20432137

RESUMO

The new Web generations are influencing the minds and changing the habits of software developers and end users. Users, librarians, and information services professionals can interact more efficiently, creating additional information and content and generating knowledge. This new scenario is also changing the behavior of information providers and users in health sciences libraries. This article reviews the new Web environments and tools that give librarians opportunities to tailor their services better, and gives some examples of the advantages and disadvantages for them and their users. Librarians need to adapt to the new mindset of users, linking new technologies, information, and people.


Assuntos
Difusão de Inovações , Internet , Serviços de Biblioteca/organização & administração
4.
Thyroid ; 30(5): 704-712, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31910118

RESUMO

Background: Although most thyroid nodules with indeterminate cytology are benign, in most of the world, surgery remains as the most frequent diagnostic approach. We have previously reported a 10-gene thyroid genetic classifier, which accurately predicts benign thyroid nodules. The assay is a prototype diagnostic kit suitable for reference laboratory testing and could potentially avoid unnecessary diagnostic surgery in patients with indeterminate thyroid cytology. Methods: Classifier performance was tested in two independent, ethnically diverse, prospective multicenter trials (TGCT-1/Chile and TGCT-2/USA). A total of 4061 fine-needle aspirations were collected from 15 institutions, of which 897 (22%) were called indeterminate. The clinical site was blind to the classifier score and the clinical laboratory blind to the pathology report. A matched surgical pathology and valid classifier score was available for 270 samples. Results: Cohorts showed significant differences, including (i) clinical site patient source (academic, 43% and 97% for TGCT-1 and -2, respectively); (ii) ethnic diversity, with a greater proportion of the Hispanic population (40% vs. 3%) for TGCT-1 and a greater proportion of African American (11% vs. 0%) and Asian (10% vs. 1%) populations for TGCT-2; and (iii) tumor size (mean of 1.7 and 2.5 cm for TGCT-1 and -2, respectively). Overall, there were no differences in the histopathological profile between cohorts. Forty-one of 155 and 45 of 115 nodules were malignant (cancer prevalence of 26% and 39% for TGCT-1 and -2, respectively). The classifier predicted 37 of 41 and 41 of 45 malignant nodules, yielding a sensitivity of 90% [95% confidence interval; CI 77-97] and 91% [95% CI 79-98] for TGCT-1 and -2, respectively. One hundred one of 114 and 61 of 70 nodules were correctly predicted as benign, yielding a specificity of 89% [95% CI 82-94] and 87% [95% CI 77-94], respectively. The negative predictive values for TGCT-1 and TGCT-2 were 96% and 94%, respectively, whereas the positive predictive values were 74% and 82%, respectively. The overall accuracy for both cohorts was 89%. Conclusions: Clinical validation of the classifier demonstrates equivalent performance in two independent and ethnically diverse cohorts, accurately predicting benign thyroid nodules that can undergo surveillance as an alternative to diagnostic surgery.


Assuntos
Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Citodiagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Adulto Jovem
5.
Thyroid ; 27(8): 1058-1067, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28521616

RESUMO

BACKGROUND: In most of the world, diagnostic surgery remains the most frequent approach for indeterminate thyroid cytology. Although several molecular tests are available for testing in centralized commercial laboratories in the United States, there are no available kits for local laboratory testing. The aim of this study was to develop a prototype in vitro diagnostic (IVD) gene classifier for the further characterization of nodules with an indeterminate thyroid cytology. METHODS: In a first stage, the expression of 18 genes was determined by quantitative polymerase chain reaction (qPCR) in a broad histopathological spectrum of 114 fresh-tissue biopsies. Expression data were used to train several classifiers by supervised machine learning approaches. Classifiers were tested in an independent set of 139 samples. In a second stage, the best classifier was chosen as a model to develop a multiplexed-qPCR IVD prototype assay, which was tested in a prospective multicenter cohort of fine-needle aspiration biopsies. RESULTS: In tissue biopsies, the best classifier, using only 10 genes, reached an optimal and consistent performance in the ninefold cross-validated testing set (sensitivity 93% and specificity 81%). In the multicenter cohort of fine-needle aspiration biopsy samples, the 10-gene signature, built into a multiplexed-qPCR IVD prototype, showed an area under the curve of 0.97, a positive predictive value of 78%, and a negative predictive value of 98%. By Bayes' theorem, the IVD prototype is expected to achieve a positive predictive value of 64-82% and a negative predictive value of 97-99% in patients with a cancer prevalence range of 20-40%. CONCLUSIONS: A new multiplexed-qPCR IVD prototype is reported that accurately classifies thyroid nodules and may provide a future solution suitable for local reference laboratory testing.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/diagnóstico , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha Fina , Chile/epidemiologia , Estudos de Coortes , Biologia Computacional , Diagnóstico Diferencial , Sistemas Inteligentes , Seguimentos , Humanos , Aprendizado de Máquina , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/epidemiologia , Nódulo da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/patologia
6.
Plant Sci ; 245: 50-60, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26940491

RESUMO

Plant growth regulators (PGRs) have become an integral part of agricultural and horticultural practices. Accordingly, there is an increased demand for new and cost-effective products. Nevertheless, the market is limited by insufficient innovation. In this context chemical genomics has gained increasing attention as a powerful approach addressing specific traits. Here is described the successful implementation of a highly specific, sensitive and efficient high throughput screening approach using Arabidopsis as a model. Using a combination of techniques, 10,000 diverse compounds were screened and evaluated for several important plant growth traits including root and leaf growth. The phenotype-based selection allowed the compilation of a collection of putative Arabidopsis growth regulators with a broad range of activities and specificities. A subset was selected for evaluating their bioactivity in agronomically valuable plants. Their validation as growth regulators in commercial species such as tomato, lettuce, carrot, maize and turfgrasses reinforced the success of the screening in Arabidopsis and indicated that small molecules activity can be efficiently translated to commercial species. Therefore, the chemical genomics approach in Arabidopsis is a promising field that can be incorporated in PGR discovery programs and has a great potential to develop new products that can be efficiently used in crops.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Ensaios de Triagem em Larga Escala/métodos , Reguladores de Crescimento de Plantas/farmacologia , Agricultura , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Genômica , Fenótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento
7.
Health Info Libr J ; 26(1): 39-46, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19245642

RESUMO

BACKGROUND: Health authorities, hospitals, commercial enterprises, and mass media all deliver health and medical communication in different forms. With such a vast amount of biomedical and clinical information available, any action to ensure the spread of clinically relevant news items is welcome. OBJECTIVES: This paper tries to define a new role for health science librarians in improving medical communication and reporting. METHODS: Literature relating to the health and medical reporting is analysed to identify major difficulties encountered by health communicators. RESULTS: There are two areas where health science librarians can develop new roles in health communication: (i) supporting journalists and health communicators in selecting sources and understanding scientific papers, and (ii) directly translating scientific information into news items, supplying a list of products in this direction (i.e. targeted newsletters, media releases, news items). New skills and competencies needed to cope with the new roles are described in detail in a suggested academic curriculum for health communicators. CONCLUSIONS: A better understanding of the mass media's needs can provide much needed support in the field of health communication.


Assuntos
Educação em Saúde/estatística & dados numéricos , Disseminação de Informação , Bibliotecas Médicas/estatística & dados numéricos , Biblioteconomia/educação , Competência Profissional/estatística & dados numéricos , Papel Profissional , Currículo , Humanos , Itália
8.
Pharmacol Res ; 50(3): 267-72, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15225669

RESUMO

Throughout the world the public is showing increasing interest in medical and scientific subjects and journalists largely spread this information, with an important impact on knowledge and health. Clearly, therefore, the relationship between the journalist and his sources is delicate: freedom and independence of information depend on the independence and truthfulness of the sources. The new "precision journalism" holds that scientific methods should be applied to journalism, so authoritative sources are a common need for journalists and scientists. We therefore compared the individual classifications and methods of assessing of sources in biomedical science and medical journalism to try to extrapolate scientific methods of evaluation to journalism. In journalism and science terms used to classify sources of information show some similarities, but their meanings are different. In science primary and secondary classes of information, for instance, refer to the levels of processing, but in journalism to the official nature of the source itself. Scientists and journalists must both always consult as many sources as possible and check their authoritativeness, reliability, completeness, up-to-dateness and balance. In journalism, however, there are some important differences and limits: too many sources can sometimes diminish the quality of the information. The sources serve a first filter between the event and the journalist, who is not providing the reader with the fact, but with its projection. Journalists have time constraints and lack the objective criteria for searching, the specific background knowledge, and the expertise to fully assess sources. To assist in understanding the wealth of sources of information in journalism, we have prepared a checklist of items and questions. There are at least four fundamental points that a good journalist, like any scientist, should know: how to find the latest information (the sources), how to assess it (the quality and authoritativeness), how to analyse and filter it (selection), how to deal with too many sources of information, sometimes case biased by conflicting interests (balance). The journalist must, in addition, know how to translate it to render it accessible and useful to the general public (dissemination), and how to use it best.


Assuntos
Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Jornalismo Médico/normas , Humanos
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