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1.
Plant Cell ; 35(12): 4238-4265, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648264

RESUMO

Variegation is a rare type of mosaicism not fully studied in plants, especially fruits. We examined red and white sections of grape (Vitis vinifera cv. 'Béquignol') variegated berries and found that accumulation of products from branches of the phenylpropanoid and isoprenoid pathways showed an opposite tendency. Light-responsive flavonol and monoterpene levels increased in anthocyanin-depleted areas in correlation with increasing MYB24 expression. Cistrome analysis suggested that MYB24 binds to the promoters of 22 terpene synthase (TPS) genes, as well as 32 photosynthesis/light-related genes, including carotenoid pathway members, the flavonol regulator HY5 HOMOLOGUE (HYH), and other radiation response genes. Indeed, TPS35, TPS09, the carotenoid isomerase gene CRTISO2, and HYH were activated in the presence of MYB24 and MYC2. We suggest that MYB24 modulates ultraviolet and high-intensity visible light stress responses that include terpene and flavonol synthesis and potentially affects carotenoids. The MYB24 regulatory network is developmentally triggered after the onset of berry ripening, while the absence of anthocyanin sunscreens accelerates its activation, likely in a dose-dependent manner due to increased radiation exposure. Anthocyanins and flavonols in variegated berry skins act as effective sunscreens but for different wavelength ranges. The expression patterns of stress marker genes in red and white sections of 'Béquignol' berries strongly suggest that MYB24 promotes light stress amelioration but only partly succeeds during late ripening.


Assuntos
Vitis , Vitis/genética , Vitis/metabolismo , Antocianinas/metabolismo , Frutas/genética , Frutas/metabolismo , Terpenos/metabolismo , Protetores Solares , Flavonóis/metabolismo , Carotenoides/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Mol Biol Rep ; 48(2): 1579-1587, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33502700

RESUMO

Stomatal closure is a common adaptation response of plants to the onset of drought condition and its regulation is controlled by transcription factors. MYB60, a transcription factor involved in the regulation of light-induced stomatal opening, has been characterized in arabidopsis and grapevine. In this work, we studied the role of MYB60 homolog SIMYB60 in tomato plants. We identified, isolated, and sequenced the SIMYB60 coding sequence, and found domains and motifs characteristic of other MYB60 proteins. We determined that SlMYB60 is mainly expressed in leaves, and its expression is repressed by abscisic acid. Next, we isolated a putative promoter region containing regulatory elements responsible for guard cell expression and other putative regulatory elements related to ABA repression and vascular tissue expression. Protein localization assays demonstrated that SlMYB60 localizes to the nucleus. Finally, SlMYB60 is able to complement the mutant phenotype of atmyb60-1 in Arabidopsis. Together, these results indicate that SlMYB60 is the homologous gene in tomato and potentially offer a molecular target to improve crops.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Secas , Solanum lycopersicum/genética , Fatores de Transcrição/genética , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Sequências Reguladoras de Ácido Nucleico/genética
3.
Sensors (Basel) ; 20(4)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098082

RESUMO

Presently, smartphones are used more and more for purposes that have nothing to do withphone calls or simple data transfers. One example is the recognition of human activity, which isrelevant information for many applications in the domains of medical diagnosis, elderly assistance,indoor localization, and navigation. The information captured by the inertial sensors of the phone(accelerometer, gyroscope, and magnetometer) can be analyzed to determine the activity performedby the person who is carrying the device, in particular in the activity of walking. Nevertheless,the development of a standalone application able to detect the walking activity starting only fromthe data provided by these inertial sensors is a complex task. This complexity lies in the hardwaredisparity, noise on data, and mostly the many movements that the smartphone can experience andwhich have nothing to do with the physical displacement of the owner. In this work, we exploreand compare several approaches for identifying the walking activity. We categorize them into twomain groups: the first one uses features extracted from the inertial data, whereas the second oneanalyzes the characteristic shape of the time series made up of the sensors readings. Due to the lackof public datasets of inertial data from smartphones for the recognition of human activity underno constraints, we collected data from 77 different people who were not connected to this research.Using this dataset, which we published online, we performed an extensive experimental validationand comparison of our proposals.


Assuntos
Smartphone , Caminhada/fisiologia , Acelerometria , Algoritmos , Atividades Humanas , Humanos
4.
Sensors (Basel) ; 18(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235803

RESUMO

Mobile phones are increasingly used for purposes that have nothing to do with phone calls or simple data transfers, and one such use is indoor inertial navigation. Nevertheless, the development of a standalone application able to detect the displacement of the user starting only from the data provided by the most common inertial sensors in the mobile phones (accelerometer, gyroscope and magnetometer), is a complex task. This complexity lies in the hardware disparity, noise on data, and mostly the many movements that the mobile phone can experience and which have nothing to do with the physical displacement of the owner. In our case, we describe a proposal, which, after using quaternions and a Kalman filter to project the sensors readings into an Earth Centered inertial reference system, combines a classic Peak-valley detector with an ensemble of SVMs (Support Vector Machines) and a standard deviation based classifier. Our proposal is able to identify and filter out those segments of signal that do not correspond to the behavior of "walking", and thus achieve a robust detection of the physical displacement and counting of steps. We have performed an extensive experimental validation of our proposal using a dataset with 140 records obtained from 75 different people who were not connected to this research.

5.
Sensors (Basel) ; 15(5): 10194-220, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25942641

RESUMO

In wireless positioning systems, the transmitter's power is usually fixed. In this paper, we explore the use of varying transmission powers to increase the performance of a wireless localization system. To this extent, we have designed a robot positioning system based on wireless motes. Our motes use an inexpensive, low-power sub-1-GHz system-on-chip (CC1110) working in the 433-MHz ISM band. Our localization algorithm is based on a particle filter and infers the robot position by: (1) comparing the power received with the expected one; and (2) integrating the robot displacement. We demonstrate that the use of transmitters that vary their transmission power over time improves the performance of the wireless positioning system significantly, with respect to a system that uses fixed power transmitters. This opens the door for applications where the robot can localize itself actively by requesting the transmitters to change their power in real time.

6.
Sensors (Basel) ; 13(1): 426-54, 2012 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-23271604

RESUMO

To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposal.

7.
Int J Radiat Oncol Biol Phys ; 70(1): 102-10, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17869446

RESUMO

PURPOSE: To compare, in a randomized trial, 5-fluorouracil (FU) plus leucovorin (LV) (FU+LV) vs. oral uracil and tegafur (UFT) plus LV (UFT+LV) given concomitantly with preoperative irradiation in patients with cT3-4 or N+ rectal cancer. METHODS AND MATERIALS: A total of 155 patients were entered onto the trial. Patients received pelvic radiotherapy (4500-5,040 cGy in 5 to 6 weeks) and chemotherapy consisting of two 5-day courses of 20 mg/m(2)/d LV and 350 mg/m(2)/d FU in the first and fifth weeks of radiotherapy (77 patients) or one course of 25 mg/d oral LV and 300 mg/m(2)/d UFT for 4 weeks beginning in the second week of radiotherapy (78 patients). The primary endpoints were pathologic complete response (pCR) and resectability rate. Secondary endpoints included downstaging rate, toxicity, and survival. RESULTS: Grade 3-5 acute hematologic toxicity occurred only with FU+LV (leukopenia 9%; p = 0.02). There were no differences in resectability rates (92.1% vs. 93.4%; p = 0.82). The pCR rate was 13.2% in both arms. Tumor downstaging was more frequent with UFT+LV (59.2% vs. 43.3%; p = 0.04). Three-year overall survival was 87% with FU+LV and 74% with UFT+LV (p = 0.37). The 3-year cumulative incidences of local recurrence were 7.5% and 8.9%, respectively (p = 0.619; relative risk, 1.46; 95% confidence interval 0.32-6.55). CONCLUSION: Although this study lacked statistical power to exclude clinically significant differences between both groups, the outcome of patients treated with UFT+LV did not differ significantly from that of patients treated with FU+LV, and hematologic toxicity was significantly lower in the experimental arm.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada/métodos , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Infusões Intravenosas , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Estudos Prospectivos , Dosagem Radioterapêutica , Neoplasias Retais/mortalidade , Neoplasias Retais/cirurgia , Análise de Sobrevida , Tegafur/administração & dosagem , Uracila/administração & dosagem , Complexo Vitamínico B/administração & dosagem
8.
Breast Cancer (Auckl) ; 12: 1178223417752772, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29434476

RESUMO

PURPOSE: As many as 50% of patients with cancer develop acute skin reactions to some degree with radiotherapy. Proactive skin care is often recommended to minimise these skin reactions and maintain the integrity of the epidermal barrier; nevertheless, no consensual guidelines are systematically used. This multicentre, observational, prospective study evaluated the tolerability and benefit of supportive and barrier protective skin care products in preventing radiotherapy-induced skin reactions in 253 women initiating radiotherapy (exclusive or adjuvant) for breast cancer. METHODS: Patients received a kit of 5 commercially available skin care products before the first radiotherapy treatment. The following variables were assessed: cutaneous adverse events, investigator-assessed skin reactions (oedema, erythema, dryness, desquamation) before and after radiotherapy course, investigator, and patient opinion on products benefit. Results were analysed by frequency of product use (heavy versus low). RESULTS: Average age was 60 years (range: 34-85). Over 92% of patients reported good to excellent tolerance on irradiated skin for each product. During the 6-week radiotherapy period, we observed that heavy product users had less skin reactions than the low users, particularly within 10 days of radiotherapy initiation (8% versus 18%; p = .031). Positive physician's opinion on product use was more frequent for high (66.6%) versus low (32%) users. Patient-assessed patient benefit index was generally >1, indicating relevant treatment benefit, with a tendency for better benefit in high versus low users. CONCLUSIONS: These results support recommendations to use skin care products to minimise the impact of secondary cutaneous reactions with radiotherapy cancer treatment.

9.
Front Plant Sci ; 8: 1486, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28936215

RESUMO

Grapevine fruit development is a dynamic process that can be divided into three stages: formation (I), lag (II), and ripening (III), in which physiological and biochemical changes occur, leading to cell differentiation and accumulation of different solutes. These stages can be positively or negatively affected by multiple environmental factors. During the last decade, efforts have been made to understand berry development from a global perspective. Special attention has been paid to transcriptional and metabolic networks associated with the control of grape berry development, and how external factors affect the ripening process. In this review, we focus on the integration of global approaches, including proteomics, metabolomics, and especially transcriptomics, to understand grape berry development. Several aspects will be considered, including seed development and the production of seedless fruits; veraison, at which anthocyanin accumulation begins in the berry skin of colored varieties; and hormonal regulation of berry development and signaling throughout ripening, focusing on the transcriptional regulation of hormone receptors, protein kinases, and genes related to secondary messenger sensing. Finally, berry responses to different environmental factors, including abiotic (temperature, water-related stress and UV-B radiation) and biotic (fungi and viruses) stresses, and how they can significantly modify both, development and composition of vine fruit, will be discussed. Until now, advances have been made due to the application of Omics tools at different molecular levels. However, the potential of these technologies should not be limited to the study of single-level questions; instead, data obtained by these platforms should be integrated to unravel the molecular aspects of grapevine development. Therefore, the current challenge is the generation of new tools that integrate large-scale data to assess new questions in this field, and to support agronomical practices.

10.
Radiother Oncol ; 67(3): 259-63, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12865173

RESUMO

PURPOSE: To assess the impact of modality therapy on long-term outcome for infradiaphragmatic Hodgkin's disease (IDHD). METHODS AND MATERIALS: During the period 1965-1997, 847 patients with early stage Hodgkin's disease (HD) were evaluated and treated at our institution, 20 of them had IDHD (2.4%). Patients characteristics: stage I, nine patients (five pathological stage (PS), and four clinical stage (CS)) and stage II: 11 patients (six PS and five CS). Two modalities of treatment were used: combined modality (CMT), consisting of chemotherapy followed by extended field radiotherapy or radiotherapy alone (XRT). All patients with CS or PS II, except in one case, were treated with CMT. Overall, 12 patients were treated with CMT and the remaining eight patients were treated with XRT. RESULTS: The relapse rate after initial treatment was 30%. Ten-year disease free survival (DFS) and 10-year cause-specific survival were 60% and 92%, respectively. There was a non-significant trend to a better DFS for the CMT group of patients (76% vs. 35% for the whole series and 100% vs. 24% for stage I patients). The four relapsed patients in the XRT group were inguino-femoral PS I. In four out of the six patients who relapsed (66%) the failure was located solely in the supradiaphragmatic area, outside of the radiation fields. CONCLUSIONS: In our experience, inguino-femoral stage I patients have a high relapse rate after XRT; consequently, CMT consisting of chemotherapy plus involved field radiotherapy should be recommended for early stage HD confined below diaphragm.


Assuntos
Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Adolescente , Adulto , Idoso , Terapia Combinada , Diafragma , Intervalo Livre de Doença , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia Adjuvante , Estudos Retrospectivos
11.
Leuk Lymphoma ; 45(6): 1133-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15359992

RESUMO

Hodgkin's disease (HD) is a curable tumoral disease. However, there are groups of patients who suffer relapse and the identification of prognostic factors and the adaptation of treatments to individual risk is one the lines of investigation in this disease. A study was performed on 526 patients diagnosed of HD in our hospital between January 1967 and September 2001. An analysis was made of the most important variables in terms of both disease-free and overall survival. Overall survival in this series of patients was 94% at 2 years, 86% at 5 years, 76% at 10 years and 72% at 15 years. Median survival was 249 months. Factors influencing poor prognosis in the overall survival were: male gender (P < 0.0001), lymphocyte depletion (P < 0.0001), stages III and IV (P < 0.0001), B symptoms (P < 0.0001), spleen involvement at diagnosis (P = 0.003), no complete remission after first line treatment (P < 0.0001), and more than 30 years-of-age (P < 0.0001). Disease free survival was 83% at 2 years and 68% at 5 years although without reaching the mean follow-up. The disease free survival study revealed the following risk factors: male gender (P = 0.02), lymphocyte depletion (P < 0.0001), stages III and IV (P < 0.001), B symptoms (P < 0.001), extranodal or splenic involvement (P < 0.05), and no complete remission after first line treatment (P < 0.0001). The result of treatment optimization is that some factors that were considered to indicate a poor prognosis have disappeared, and that others which are useful have appeared and allow us to establish groups with differing risks of relapse and who could be candidates for differentiated treatments.


Assuntos
Doença de Hodgkin/diagnóstico , Adulto , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/terapia , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , Indução de Remissão , Taxa de Sobrevida , Resultado do Tratamento
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