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1.
Plants (Basel) ; 12(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36840081

RESUMO

Potato (Solanum tuberosum L.) is often considered a water-sensitive crop and its production can be threatened by drought events, making water stress tolerance a trait of increasing interest. In this study, a panel of 144 tetraploid potato genotypes was evaluated for two consecutive years (2019 and 2020) to observe the variation of several physiological traits such as chlorophyll content and fluorescence, stomatal conductance, NDVI, and leaf area and circumference. In addition, agronomic parameters such as yield, tuber fresh weight, tuber number, starch content, dry matter and reducing sugars were determined. GGP V3 Potato array was used to genotype the population, obtaining a total of 18,259 high-quality SNP markers. Marker-trait association was performed using GWASpoly package in R software and Q + K linear mixed models were considered. This approach allowed us to identify eighteen SNP markers significantly associated with the studied traits in both treatments and years, which were related to genes with known functions. Markers related to chlorophyll content and number of tubers under control and stress conditions, and related to stomatal conductance, NDVI, yield and reducing sugar content under water stress, were identified. Although these markers were distributed throughout the genome, the SNPs associated with the traits under control conditions were found mainly on chromosome 11, while under stress conditions they were detected on chromosome 4. These results contribute to the knowledge of the mechanisms of potato tolerance to water stress and are useful for future marker-assisted selection programs.

2.
Int J Mol Sci ; 23(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36430379

RESUMO

Potato (Solanum tuberosum L.) is one of the most important crops worldwide, but due to its sensitivity to drought, its production can be affected by water availability. In this study, the varieties Agria and Zorba were used to determine the expression differences between control and water-stressed plants. For this purpose, they were sequenced by RNAseq, obtaining around 50 million transcripts for each variety and treatment. When comparing the significant transcripts obtained from control and drought-stressed plants of the Agria variety, we detected 931 genes that were upregulated and 2077 genes that were downregulated under stress conditions. When both treatments were compared in Zorba plants, 735 genes were found to be upregulated and 923 genes were found to be downregulated. Significantly more DEGs were found in the Agria variety, indicating a good stress response of this variety. "Abscisic acid and environmental stress-inducible protein TAS14-like" was the most overexpressed gene under drought conditions in both varieties, but expression differences were also found in numerous transcription factors and heat shock proteins. The principal GO term found was "cellular components", more specifically related to the cell membrane and the cell wall, but other metabolic pathways such as carbohydrate metabolism and osmotic adjustment were also identified. These results provide valuable information related to the molecular mechanisms of tolerance to water stress in order to establish the basis for breeding new, more tolerant varieties.


Assuntos
Solanum tuberosum , Solanum tuberosum/metabolismo , Desidratação/genética , Tetraploidia , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Perfilação da Expressão Gênica
3.
Front Nutr ; 9: 999877, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324619

RESUMO

The potato (Solanum tuberosum L.) is the world's fifth most important staple food with high socioeconomic relevance. Several potato cultivars obtained by selection and crossbreeding are currently on the market. This diversity causes tubers to exhibit different behaviors depending on the processing to which they are subjected. Therefore, it is interesting to identify cultivars with specific characteristics that best suit consumer preferences. In this work, we present a method to classify potatoes according to their cooking or frying as crisps aptitude using NIR hyperspectral imaging (HIS) combined with a Partial Least Squares Discriminant Analysis (PLS-DA). Two classification approaches were used in this study. First, a classification model using the mean spectra of a dataset composed of 80 tubers belonging to 10 different cultivars. Then, a pixel-wise classification using all the pixels of each sample of a small subset of samples comprised of 30 tubers. Hyperspectral images were acquired using fresh-cut potato slices as sample material placed on a mobile platform of a hyperspectral system in the NIR range from 900 to 1,700 nm. After image processing, PLS-DA models were built using different pre-processing combinations. Excellent accuracy rates were obtained for the models developed using the mean spectra of all samples with 90% of tubers correctly classified in the external dataset. Pixel-wise classification models achieved lower accuracy rates between 66.62 and 71.97% in the external validation datasets. Moreover, a forward interval PLS (iPLS) method was used to build pixel-wise PLS-DA models reaching accuracies above 80 and 71% in cross-validation and external validation datasets, respectively. Best classification result was obtained using a subset of 100 wavelengths (20 intervals) with 71.86% of pixels correctly classified in the validation dataset. Classification maps were generated showing that false negative pixels were mainly located at the edges of the fresh-cut slices while false positive were principally distributed at the central pith, which has singular characteristics.

4.
Future Oncol ; 18(31): 3501-3508, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36367446

RESUMO

Background: The COVID-19 pandemic caused discontinuities in cancer care (CC) in most countries. Here, the authors describe the real-world impacts of implementing a contingency plan employing telemedicine for CC. Methods: A retrospective study of patients who received CC through telemedicine at the Instituto Nacional de Enfermedades Neoplasicas, Peru, from March 2020 to February 2021 was conducted. Impacts were measured by comparing the amount of CC administered during the pandemic versus the prior year. Results: A total of 16,456 telemedicine visits were carried out. An annual comparative analysis showed a gap of 23% and telemedicine accounted for 27.6% of the total CC administered during the pandemic. A high (4.50/5) level of patient satisfaction with telemedicine was reported. Conclusion: Telemedicine is an important tool to facilitate the continuity of CC.


Assuntos
COVID-19 , Neoplasias , Telemedicina , Humanos , Pandemias , COVID-19/epidemiologia , Peru/epidemiologia , Estudos Retrospectivos , Neoplasias/epidemiologia , Neoplasias/terapia , Satisfação do Paciente
5.
Front Oncol ; 12: 850351, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371998

RESUMO

Purpose: The purpose of this study was to assess the effectivity of upfront kilovoltage intraoperative radiotherapy (IORT) as a boost in high-risk early-stage breast cancer patients from an international pooled cohort. Materials/Methods: Patients from four centers in three different countries were retrospectively screened. Those with a minimum 1-year follow-up were included. Cumulative local (LR), regional (RR), and distant metastasis rates (DM) were analyzed. Additionally, the estimated overall survival (OS) was assessed. The Cox regression analysis was performed to identify failure predicting factors. Results: A total of 653 patients from centers in Peru, Spain, and Germany were included. The median follow-up was 55 (12-180) months, and age was 58 (27-86) years. Clinical tumor (T) staging was T1 65.85%, T2 30.17%, and T3 3.98%. Positive margins were found in 7.9% and in-situ component in 20.06%. The median IORT dose was 20 (6-20). The median time from IORT to EBRT was 74.5 (13-364) days. An overall 3.4% (n = 22) of patients developed local recurrence at some point during follow-up. The 12-, 60-, and 120-month cumulative LR were 0.3%, 2.3%, and 7.9%, respectively. After multivariate analysis, only age <50 remained to be a significant prognostic factor for local recurrence (HR 0.19, 95% CI 0.08-0.47; p < 0.05). The 10-year estimated OS was 81.2%. Conclusion: Upfront boost with IORT yields similar local control outcomes to those EBRT-based reports. Results from prospective trials, regarding toxicity, cosmesis, and effectivity are awaited to confirm these findings.

6.
Front Nutr ; 8: 683399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071287

RESUMO

Maize (Zea mays L.) is one of the major crops of the world for feed, food, and industrial uses. It was originated in Central America and introduced into Europe and other continents after Columbus trips at the end of the 15th century. Due to the large adaptability of maize, farmers have originated a wide variability of genetic resources with wide diversity of adaptation, characteristics, and uses. Nowadays, in Europe, maize is mainly used for feed, but several food specialties were originated during these five centuries of maize history and became traditional food specialties. This review summarizes the state of the art of traditional foodstuffs made with maize in Southern, South-Western and South-Eastern Europe, from an historic evolution to the last research activities that focus on improving sustainability, quality and safety of food production.

7.
Ecancermedicalscience ; 14: 1115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33209106

RESUMO

INTRODUCTION: The COVID-19 pandemic has changed health systems across the world, both in general hospitals and in oncology institutes or centres.For cancer specialists, particularly breast cancer (BC), the COVID-19 pandemic represents a combination of challenges since the hospital resources and staff have become more limited; this has obliged oncology specialists to seek a consensus and establish which patients with BC require more urgent attention and which patients can wait until there is a better control of this pandemic. The health system in Latin America has some special characteristics; in some of the countries, there are shortages which limit access to several specialities (surgery, clinical oncology and radiotherapy) in some regions. OBJECTIVE: After a systematic review of the most recent literature regarding the management of BC during the COVID-19 pandemic, the main objective is to understand the position of the different Latin American Societies of Mastology in terms of available alternatives for the treatment of BC. METHODS: After carrying out a comprehensive and exhaustive search of the most recent guides on the management of BC during the COVID-19 pandemic, the board members of the Latin American Federation of Mastology invited, via email, different specialists, all experts in BC care, to complete an anonymous survey online.The survey was distributed between 30 and 10 May 2020. The survey included 27 questions on four topics: demographic information, consultations, imaging and treatment of BC.The questionnaire was sent and then distributed to various health specialists including breast surgeons, clinical oncologists, radiation oncologists and radiologists via the Presidents of the different Latin American Societies of Mastology in 18 countries. The results are summarised as tallies based on the number of responses to each question. RESULTS: A total of 499 responses were received. The majority of the respondents were males (275 (55.11%)); 290 participants were over 45 years (58.11%).The questionnaire presented those surveyed with three possible answers (agree, disagree and neither agree nor disagree). The results reflect that there was consensus in the majority of situations presented. Only seven questions revealed disagreement among those responding. The results are presented as recommendations. CONCLUSION: The management of patients with BC presents unique challenges during the current world health situation produced by COVID-19 pandemic. Breast care specialists (surgical oncologists, breast care clinicians, clinical oncologists, radiation oncologists and radiologists) from 18 countries in Central and South America submitted through their responses and recommendations for the treatment of BC during the COVID-19 pandemic.

8.
Cir Esp (Engl Ed) ; 97(4): 203-212, 2019 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30777256

RESUMO

INTRODUCTION: Soft tissue sarcomas (SFT) are a group of rare and heterogeneous neoplasms (representing less than 1% of cancer in adults and 15% in pediatric patients), for which there is no updated records in the Latin American population. This study aims to describe the current situation of patients treated at a cancer institute in Latin America. METHODS: We obtained records from 250 patients with a diagnosis of SFT, treated at the National Institute of Neoplastic Diseases of Peru (INEN) during the period 2009-2013, with a mean follow-up of 62 months. The following data were recorded: epidemiological, clinical, treatment and follow-up. The analysis of global survival was done with the Cox proportional hazards model. RESULTS: SFT showed a greater frequency in males (60.8%), with a peak incidence after 50 years of age (69.6%). Tumor location was predominantly in the lower extremities (64.4%), and the most frequent histologic subtypes were: undifferentiated pleomorphic sarcoma (34%) and liposarcomas (25.6%); clinical stage iii was the most frequent (30.8%). The 5-year overall survival rate was 63.9%, while the statistical analysis found a significant association between global survival and the variables: age (>50 years), tumor size (>5cm), depth (subfascial), histologic grade (G3), local and distant recurrence, showing shorter survival times in these groups. CONCLUSIONS: This study has clarified the epidemiology, treatment and prognosis, as well as the variables that have an impact on the survival of the Latin American patients with SFT studied.


Assuntos
Sarcoma/epidemiologia , Sarcoma/mortalidade , Neoplasias de Tecidos Moles/epidemiologia , Neoplasias de Tecidos Moles/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , América Latina/epidemiologia , Lipossarcoma/patologia , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Adulto Jovem
9.
BMC Plant Biol ; 16(1): 127, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27267760

RESUMO

BACKGROUND: Breeding for cold tolerance in maize promises to allow increasing growth area and production in temperate zones. The objective of this research was to conduct genome-wide association analyses (GWAS) in temperate maize inbred lines and to find strategies for pyramiding genes for cold tolerance. Two panels of 306 dent and 292 European flint maize inbred lines were evaluated per se and in testcrosses under cold and control conditions in a growth chamber. We recorded indirect measures for cold tolerance as the traits number of days from sowing to emergence, relative leaf chlorophyll content or quantum efficiency of photosystem II. Association mapping for identifying genes associated to cold tolerance in both panels was based on genotyping with 49,585 genome-wide single nucleotide polymorphism (SNP) markers. RESULTS: We found 275 significant associations, most of them in the inbreds evaluated per se, in the flint panel, and under control conditions. A few candidate genes coincided between the current research and previous reports. A total of 47 flint inbreds harbored the favorable alleles for six significant quantitative trait loci (QTL) detected for inbreds per se evaluated under cold conditions, four of them had also the favorable alleles for the main QTL detected from the testcrosses. Only four dent inbreds (EZ47, F924, NK807 and PHJ40) harbored the favorable alleles for three main QTL detected from the evaluation of the dent inbreds per se under cold conditions. There were more QTL in the flint panel and most of the QTL were associated with days to emergence and ΦPSII. CONCLUSIONS: These results open new possibilities to genetically improve cold tolerance either with genome-wide selection or with marker assisted selection.


Assuntos
Temperatura Baixa , Estresse Fisiológico/genética , Zea mays/genética , Alelos , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Estudo de Associação Genômica Ampla , Genótipo , Desequilíbrio de Ligação/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
10.
J Sci Food Agric ; 96(6): 1888-99, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26058597

RESUMO

BACKGROUND: Over the last two decades, the attractive colours and shapes of pigmented tubers and the increasing concern about the relationship between nutrition and health have contributed to the expansion of their consumption and a specialty market. Thus, we have quantified the concentration of health promoting compounds such as soluble phenolics, monomeric anthocyanins, carotenoids, vitamin C, and hydrophilic antioxidant capacity, in a collection of 18 purple- and red-fleshed potato accessions. RESULTS: Cultivars and breeding lines high in vitamin C, such as Blue Congo, Morada and Kasta, have been identified. Deep purple cultivars Violet Queen, Purple Peruvian and Vitelotte showed high levels of soluble phenolics, monomeric anthocyanins, and hydrophilic antioxidant capacity, whereas relatively high carotenoid concentrations were found in partially yellow coloured tubers, such as Morada, Highland Burgundy Red, and Violet Queen. CONCLUSION: The present characterisation of cultivars and breeding lines with high concentrations of phytochemicals is an important step both to support the consideration of specialty potatoes as a source of healthy compounds, and to obtain new cultivars with positive nutritional characteristics. Moreover, by using near infrared spectroscopy a non-destructive identification and classification of samples with different levels of phytochemicals is achieved, offering an unquestionable contribution to the potato industry for future automatic discrimination of varieties.


Assuntos
Ácido Ascórbico/química , Carotenoides/química , Tubérculos/química , Solanum tuberosum/química , Espectrofotometria Infravermelho/métodos
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