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1.
Front Plant Sci ; 14: 1268014, 2023.
Article in English | MEDLINE | ID: mdl-38023922

ABSTRACT

Climate change is considered a serious threat to agriculture and food security. It is linked to rising temperatures and water shortages, conditions that are expected to worsen in the coming decades. Consequently, the introduction of more drought-tolerant crops is required. Quinoa (Chenopodium quinoa Willd.) has received great attention worldwide due to the nutritional properties of its seeds and its tolerance to abiotic stress. In this work, the agronomic performance and seed nutritional quality of three quinoa varieties were studied during two consecutive years (2019-2020) under three water environmental conditions of Southwestern Europe (irrigated conditions, fresh rainfed, and hard rainfed) with the goal of determining the impact of rainfed conditions on this crop performance. High precipitations were recorded during the 2020 growing season resulting in similar grain yield under irrigation and fresh rainfed conditions. However, in 2019, significant yield differences with penalties under water-limiting conditions were found among the evaluated environmental conditions. Furthermore, nutritional and metabolomic differences were observed among seeds harvested from different water environments including the progressive accumulation of glycine betaine accompanied by an increase in saponin and a decrease in iron with water limitation. Generally, water-limiting environments were associated with increased protein contents and decreased yields preserving a high nutritional quality despite particular changes. Overall, this work contributes to gaining further knowledge about how water availability affects quinoa field performance, as it might impact both seed yield and quality. It also can help reevaluate rainfed agriculture, as water deficit can positively impact the nutritional quality of seeds.

2.
Sci Rep ; 13(1): 4951, 2023 03 27.
Article in English | MEDLINE | ID: mdl-36973333

ABSTRACT

Quinoa is an Andean crop whose cultivation has been extended to many different parts of the world in the last decade. It shows a great capacity for adaptation to diverse climate conditions, including environmental stressors, and, moreover, the seeds are very nutritious in part due to their high protein content, which is rich in essential amino acids. They are gluten-free seeds and contain good amounts of other nutrients such as unsaturated fatty acids, vitamins, or minerals. Also, the use of quinoa hydrolysates and peptides has been linked to numerous health benefits. Altogether, these aspects have situated quinoa as a crop able to contribute to food security worldwide. Aiming to deepen our understanding of the protein quality and function of quinoa seeds and how they can vary when this crop is subjected to water-limiting conditions, a shotgun proteomics analysis was performed to obtain the proteomes of quinoa seeds harvested from two different water regimes in the field: rainfed and irrigated conditions. Differentially increased levels of proteins determined in seeds from each field condition were analysed, and the enrichment of chitinase-related proteins in seeds harvested from rainfed conditions was found. These proteins are described as pathogen-related proteins and can be accumulated under abiotic stress. Thus, our findings suggest that chitinase-like proteins in quinoa seeds can be potential biomarkers of drought. Also, this study points to the need for further research to unveil their role in conferring tolerance when coping with water-deficient conditions.


Subject(s)
Chenopodium quinoa , Chitinases , Chenopodium quinoa/chemistry , Chitinases/metabolism , Proteomics , Seeds/chemistry , Water/metabolism
3.
Healthcare (Basel) ; 10(2)2022 Jan 29.
Article in English | MEDLINE | ID: mdl-35206876

ABSTRACT

(1) Objective. We aimed to demonstrate that the use of the ultrasound-guided technique facilitates peripheral venous cannulation as compared to the standard technique in patients with difficult access at emergency services. (2) Method. A case-control study, randomized research. Variables were collected from a population with non-palpable or not visible veins, classified into size risk groups for 6 months. In the comparative analysis, the patients were divided into two groups: the cases group was composed of patients to whom the peripheral venous cannulation was performed with the ultrasound-guided technique (UST), while the control was composed of patients with whom the standard technique (ST) was performed. The ultrasound LOGIQ P5 750VA from General Electric Healthcare, with an 11 mHz linear probe, was utilized, along with peripheral venous catheters model InsyteTM AutoguardTM with gauges of 14G to 26G. (3) Results. Seventy-two cases. The use of the ultrasound decreased the time (618.34s ST, 126s UST) and the number of punctures (2.92 ST, 1.23 UST); about 25% of the patients did not have complications with the UST, as compared to 8% with the ST. The use of the ultrasound decreased the pain experienced by 1.44 points in the visual analog scale, as compared to 0.11 points with the ST. The rate of success of the first try with the UST was 76%, as compared to 16% of the ST. The gauge of the catheter increased with the UST, with successful cannulations obtained with 20G (56%) and 18G (41%) gauges. (4) Conclusions. The use of ultrasound facilitates venous cannulation according to the variables of the study. The ultrasound visualization of the vessels is associated with the selection of the catheter gauge. There was no relation between the complications and the depth of the blood vessels.

4.
NMR Biomed ; 34(4): e4462, 2021 04.
Article in English | MEDLINE | ID: mdl-33470039

ABSTRACT

INTRODUCTION: IDH1/2 wt glioblastoma (GB) represents the most lethal tumour of the central nervous system. Tumour vascularity is associated with overall survival (OS), and the clinical relevance of vascular markers, such as rCBV, has already been validated. Nevertheless, molecular and clinical factors may have different influences on the beneficial effect of a favourable vascular signature. PURPOSE: To evaluate the association between the rCBV and OS of IDH1/2 wt GB patients for long-term survivors (LTSs) and short-term survivors (STSs). Given that initial high rCBV may affect the patient's OS in follow-up stages, we will assess whether a moderate vascularity is beneficial for OS in both groups of patients. MATERIALS AND METHODS: Ninety-nine IDH1/2 wt GB patients were divided into LTSs (OS ≥ 400 days) and STSs (OS < 400 days). Mann-Whitney and Fisher, uni- and multiparametric Cox, Aalen's additive regression and Kaplan-Meier tests were carried out. Tumour vascularity was represented by the mean rCBV of the high angiogenic tumour (HAT) habitat computed through the haemodynamic tissue signature methodology (available on the ONCOhabitats platform). RESULTS: For LTSs, we found a significant association between a moderate value of rCBVmean and higher OS (uni- and multiparametric Cox and Aalen's regression) (p = 0.0140, HR = 1.19; p = 0.0085, HR = 1.22) and significant stratification capability (p = 0.0343). For the STS group, no association between rCBVmean and survival was observed. Moreover, no significant differences (p > 0.05) in gender, age, resection status, chemoradiation, or MGMT methylation were observed between LTSs and STSs. CONCLUSION: We have found different prognostic and stratification effects of the vascular marker for the LTS and STS groups. We propose the use of rCBVmean at HAT as a vascular marker clinically relevant for LTSs with IDH1/2 wt GB and maybe as a potential target for randomized clinical trials focused on this group of patients.


Subject(s)
Brain Neoplasms/blood supply , Cancer Survivors , Glioblastoma/blood supply , Isocitrate Dehydrogenase/genetics , Blood Volume , Brain Neoplasms/genetics , Brain Neoplasms/mortality , Cerebrovascular Circulation , DNA Modification Methylases/genetics , DNA Repair Enzymes/genetics , Female , Glioblastoma/genetics , Glioblastoma/mortality , Humans , Male , Middle Aged , Proportional Hazards Models , Tumor Suppressor Proteins/genetics
5.
Eur Radiol ; 31(3): 1738-1747, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33001310

ABSTRACT

OBJECTIVES: To assess the combined role of tumor vascularity, estimated from perfusion MRI, and MGMT methylation status on overall survival (OS) in patients with glioblastoma. METHODS: A multicentric international dataset including 96 patients from NCT03439332 clinical study were used to study the prognostic relationships between MGMT and perfusion markers. Relative cerebral blood volume (rCBV) in the most vascularized tumor regions was automatically obtained from preoperative MRIs using ONCOhabitats online analysis service. Cox survival regression models and stratification strategies were conducted to define a subpopulation that is particularly favored by MGMT methylation in terms of OS. RESULTS: rCBV distributions did not differ significantly (p > 0.05) in the methylated and the non-methylated subpopulations. In patients with moderately vascularized tumors (rCBV < 10.73), MGMT methylation was a positive predictive factor for OS (HR = 2.73, p = 0.003, AUC = 0.70). In patients with highly vascularized tumors (rCBV > 10.73), however, there was no significant effect of MGMT methylation (HR = 1.72, p = 0.10, AUC = 0.56). CONCLUSIONS: Our results indicate the existence of complementary prognostic information provided by MGMT methylation and rCBV. Perfusion markers could identify a subpopulation of patients who will benefit the most from MGMT methylation. Not considering this information may lead to bias in the interpretation of clinical studies. KEY POINTS: • MRI perfusion provides complementary prognostic information to MGMT methylation. • MGMT methylation improves prognosis in glioblastoma patients with moderate vascular profile. • Failure to consider these relations may lead to bias in the interpretation of clinical studies.


Subject(s)
Brain Neoplasms , Glioblastoma , Antineoplastic Agents, Alkylating/therapeutic use , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , DNA Methylation , DNA Modification Methylases/genetics , DNA Repair Enzymes/genetics , Glioblastoma/diagnostic imaging , Glioblastoma/genetics , Humans , Prognosis , Promoter Regions, Genetic , Temozolomide/therapeutic use , Tumor Suppressor Proteins/genetics
6.
Phys Med ; 76: 44-54, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32593138

ABSTRACT

PURPOSE: To evaluate the potential of 2D texture features extracted from magnetic resonance (MR) images for differentiating brain metastasis (BM) and glioblastomas (GBM) following a radiomics approach. METHODS: This retrospective study included 50 patients with BM and 50 with GBM who underwent T1-weighted MRI between December 2010 and January 2017. Eighty-eight rotation-invariant texture features were computed for each segmented lesion using six texture analysis methods. These features were also extracted from the four images obtained after applying the discrete wavelet transform (88 features × 4 images). Three feature selection methods and five predictive models were evaluated. A 5-fold cross-validation scheme was used to randomly split the study group into training (80 patients) and testing (20 patients), repeating the process ten times. Classification was evaluated computing the average area under the receiver operating characteristic curve. Sensibility, specificity and accuracy were also computed. The whole process was tested quantizing the images with different gray-level values to evaluate their influence in the final results. RESULTS: Highest classification accuracy was obtained using the original images quantized with 128 gray-levels and a feature selection method based on the p-value. The best overall performance was achieved using a support vector machine model with a subset of 32 features (AUC = 0.896 ± 0.067, sensitivity of 82% and specificity of 80%). Naïve Bayes and k-nearest neighbors models showed also valuable results (AUC ≈ 0.8) with a lower number of features (<13), thus suggesting that these models may be more generalizable when using external validations. CONCLUSION: The proposed radiomics MRI approach is able to discriminate between GBM and BM with high accuracy employing a set of 2D texture features, thus helping in the diagnosis of brain lesions in a fast and non-invasive way.


Subject(s)
Brain Neoplasms , Glioblastoma , Bayes Theorem , Brain Neoplasms/diagnostic imaging , Glioblastoma/diagnostic imaging , Humans , Magnetic Resonance Imaging , Retrospective Studies
7.
Plant Cell Physiol ; 61(4): 814-825, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32016408

ABSTRACT

Cell wall modification is integral to many plant developmental processes where cells need to separate, such as abscission. However, changes in cell wall composition during natural fruit abscission are poorly understood. In olive (Olea europaea L.), some cultivars such as 'Picual' undergo massive natural fruit abscission after fruit ripening. This study investigates the differences in cell wall polysaccharide composition and the localization of pectins and arabinogalactan protein (AGP) in the abscission zone (AZ) during cell separation to understand fruit abscission control in 'Picual' olive. To this end, immunogold labeling employing a suite of monoclonal antibodies to cell wall components (JIM13, LM5, LM6, LM19 and LM20) was investigated in olive fruit AZ. Cell wall polysaccharide extraction revealed that the AZ cell separation is related to the de-esterification and degradation of pectic polysaccharides. Moreover, ultrastructural localization showed that both esterified and unesterified homogalacturonans (HGs) localize mainly in the AZ cell walls, including the middle lamella and tricellular junction zones. Our results indicate that unesterified HGs are likely to contribute to cell separation in the olive fruit AZ. Similarly, immunogold labeling demonstrated a decrease in both galactose-rich and arabinose-rich pectins in AZ cell walls during ripe fruit abscission. In addition, AGPs were localized in the cell wall, plasma membrane and cytoplasm of AZ cells with lower levels of AGPs during ripe fruit abscission. This detailed temporal profile of the cell wall polysaccharide composition, and the pectins and AGP immunolocalization in the olive fruit AZ, offers new insights into cell wall remodeling during ripe fruit abscission.


Subject(s)
Cell Wall/ultrastructure , Fruit/chemistry , Galactans/ultrastructure , Mucoproteins/ultrastructure , Olea/chemistry , Pectins/ultrastructure , Arabinose/metabolism , Esterification , Galactose/metabolism , Plant Proteins/ultrastructure , Polysaccharides/ultrastructure
8.
J Magn Reson Imaging ; 51(5): 1478-1486, 2020 05.
Article in English | MEDLINE | ID: mdl-31654541

ABSTRACT

BACKGROUND: Glioblastoma (GBM) is the most aggressive primary brain tumor, characterized by a heterogeneous and abnormal vascularity. Subtypes of vascular habitats within the tumor and edema can be distinguished: high angiogenic tumor (HAT), low angiogenic tumor (LAT), infiltrated peripheral edema (IPE), and vasogenic peripheral edema (VPE). PURPOSE: To validate the association between hemodynamic markers from vascular habitats and overall survival (OS) in glioblastoma patients, considering the intercenter variability of acquisition protocols. STUDY TYPE: Multicenter retrospective study. POPULATION: In all, 184 glioblastoma patients from seven European centers participating in the NCT03439332 clinical study. FIELD STRENGTH/SEQUENCE: 1.5T (for 54 patients) or 3.0T (for 130 patients). Pregadolinium and postgadolinium-based contrast agent-enhanced T1 -weighted MRI, T2 - and FLAIR T2 -weighted, and dynamic susceptibility contrast (DSC) T2 * perfusion. ASSESSMENT: We analyzed preoperative MRIs to establish the association between the maximum relative cerebral blood volume (rCBVmax ) at each habitat with OS. Moreover, the stratification capabilities of the markers to divide patients into "vascular" groups were tested. The variability in the markers between individual centers was also assessed. STATISTICAL TESTS: Uniparametric Cox regression; Kaplan-Meier test; Mann-Whitney test. RESULTS: The rCBVmax derived from the HAT, LAT, and IPE habitats were significantly associated with patient OS (P < 0.05; hazard ratio [HR]: 1.05, 1.11, 1.28, respectively). Moreover, these markers can stratify patients into "moderate-" and "high-vascular" groups (P < 0.05). The Mann-Whitney test did not find significant differences among most of the centers in markers (HAT: P = 0.02-0.685; LAT: P = 0.010-0.769; IPE: P = 0.093-0.939; VPE: P = 0.016-1.000). DATA CONCLUSION: The rCBVmax calculated in HAT, LAT, and IPE habitats have been validated as clinically relevant prognostic biomarkers for glioblastoma patients in the pretreatment stage. This study demonstrates the robustness of the hemodynamic tissue signature (HTS) habitats to assess the GBM vascular heterogeneity and their association with patient prognosis independently of intercenter variability. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:1478-1486.


Subject(s)
Brain Neoplasms , Glioblastoma , Brain Neoplasms/diagnostic imaging , Contrast Media , Glioblastoma/diagnostic imaging , Humans , Magnetic Resonance Imaging , Prognosis , Retrospective Studies
9.
Int J Mol Sci ; 20(10)2019 May 15.
Article in English | MEDLINE | ID: mdl-31096545

ABSTRACT

Acute lymphoblastic leukemia is the most common type of childhood cancer worldwide. Mexico City has one of the highest incidences and mortality rates of this cancer. It has previously been recognized that chromosomal translocations are important in cancer etiology. Specific fusion genes have been considered as important treatment targets in childhood acute lymphoblastic leukemia (ALL). The present research aimed at the identification and characterization of novel fusion genes with potential clinical implications in Mexican children with acute lymphoblastic leukemia. The RNA-sequencing approach was used. Four fusion genes not previously reported were identified: CREBBP-SRGAP2B, DNAH14-IKZF1, ETV6-SNUPN, ETV6-NUFIP1. Although a fusion gene is not sufficient to cause leukemia, it could be involved in the pathogenesis of the disease. Notably, these new translocations were found in genes encoding for hematopoietic transcription factors which are known to play an important role in leukemogenesis and disease prognosis such as IKZF1, CREBBP, and ETV6. In addition, they may have an impact on the prognosis of Mexican pediatric patients with ALL, with the potential to be included in the current risk stratification schemes or used as therapeutic targets.


Subject(s)
Oncogene Proteins, Fusion/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Translocation, Genetic/genetics , Adolescent , Adult , CREB-Binding Protein/genetics , Child , Child, Preschool , Dyneins/genetics , Female , GTPase-Activating Proteins/genetics , Gene Expression Regulation, Neoplastic , Gene Rearrangement , Humans , Ikaros Transcription Factor/genetics , Infant , Male , Mexico , Nuclear Proteins/genetics , Prognosis , Proto-Oncogene Proteins c-ets/genetics , RNA Cap-Binding Proteins/genetics , RNA-Binding Proteins/genetics , Receptors, Cytoplasmic and Nuclear/genetics , Repressor Proteins/genetics , Young Adult , ETS Translocation Variant 6 Protein
10.
Diagnostics (Basel) ; 8(3)2018 Jul 19.
Article in English | MEDLINE | ID: mdl-30029524

ABSTRACT

The current criteria for diagnosing Alzheimer's disease (AD) require the presence of relevant cognitive deficits, so the underlying neuropathological damage is important by the time the diagnosis is made. Therefore, the evaluation of new biomarkers to detect AD in its early stages has become one of the main research focuses. The purpose of the present study was to evaluate a set of texture parameters as potential biomarkers of the disease. To this end, the ALTEA (ALzheimer TExture Analyzer) software tool was created to perform 2D and 3D texture analysis on magnetic resonance images. This intuitive tool was used to analyze textures of circular and spherical regions situated in the right and left hippocampi of a cohort of 105 patients: 35 AD patients, 35 patients with early mild cognitive impairment (EMCI) and 35 cognitively normal (CN) subjects. A total of 25 statistical texture parameters derived from the histogram, the Gray-Level Co-occurrence Matrix and the Gray-Level Run-Length Matrix, were extracted from each region and analyzed statistically to study their predictive capacity. Several textural parameters were statistically significant (p < 0.05) when differentiating AD subjects from CN and EMCI patients, which indicates that texture analysis could help to identify the presence of AD.

11.
Front Plant Sci ; 8: 1092, 2017.
Article in English | MEDLINE | ID: mdl-28676820

ABSTRACT

Arabinogalactan proteins (AGPs) are a highly diverse family of glycoproteins that are commonly found in most plant species. However, little is known about the physiological and molecular mechanisms of their function. AGPs are involved in different biological processes such as cell differentiation, cell expansion, tissue development and somatic embryogenesis. AGPs are also involved in abiotic stress response such as salinity modulating cell wall expansion. In this study, we describe how salt-adaptation in tobacco BY-2 cell cultures induces important changes in arabinogalactan proteins distribution and contents. Using the immuno-dot blot technique with different anti-AGP antibodies (JIM13, JIM15, and others), we observed that AGPs were highly accumulated in the culture medium of salt-adapted tobacco cells, probably due to the action of phospholipases. We located these AGP epitopes using immunogold labeling in the cytoplasm associated to the endoplasmic reticulum, the golgi apparatus, and vesicles, plasma membrane and tonoplast. Our results show that salt-adaptation induced a significant reduction of the cytoplasm, plasma membrane and tonoplast content of these epitopes. Yariv reagent was added to the control and salt-adapted tobacco cell cultures, leading to cell death induction in control cells but not in salt-adapted cells. Ultrastructural and immunogold labeling revealed that cell death induced by Yariv reagent in control cells was due to the interaction of Yariv reagent with the AGPs linked to the plasma membranes. Finally, we propose a new function of AGPs as a possible sodium carrier through the mechanism of vesicle trafficking from the apoplast to the vacuoles in salt-adapted tobacco BY-2 cells. This mechanism may contribute to sodium homeostasis during salt-adaptation to high saline concentrations.

12.
Eur Radiol ; 27(8): 3392-3400, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27999986

ABSTRACT

OBJECTIVES: Vascular characteristics of tumour and peritumoral volumes of high-grade gliomas change with treatment. This work evaluates the variations of T2*-weighted perfusion parameters as overall survival (OS) predictors. METHODS: Forty-five patients with histologically confirmed high-grade astrocytoma (8 grade III and 37 grade IV) were included. All patients underwent pre- and post-treatment T2*-weighted contrast-enhanced magnetic resonance (MR) imaging. Tumour, peritumoral and control volumes were segmented. Relative variations of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), Ktrans-T2*, kep-T2*, ve-T2* and vp-T2* were calculated. Differences regarding tumour grade and surgical resection extension were evaluated with ANOVA tests. For each parameter, two groups were defined by non-supervised clusterisation. Survival analysis were performed on these groups. RESULTS: For the tumour region, the 90th percentile increase or stagnation of CBV was associated with shorter survival, while a decrease related to longer survival (393 ± 189 vs 594 ± 294 days; log-rank p = 0.019; Cox hazard-ratio, 2.31; 95% confidence interval [CI], 1.12-4.74). Ktrans-T2* showed similar results (414 ± 177 vs 553 ± 312 days; log-rank p = 0.037; hazard-ratio, 2.19; 95% CI, 1.03-4.65). The peritumoral area values showed no relationship with OS. CONCLUSIONS: Post-treatment variations of the highest CBV and Ktrans-T2* values in the tumour volume are predictive factors of OS in patients with high-grade gliomas. KEY POINTS: • Vascular characteristics of high-grade glioma tumour and peritumoral regions change with treatment. • Quantitative assessment of MRI perfusion provides valuable information regarding tumour aggressiveness. • Quantitative T2*-weighted perfusion parameters can help to predict overall survival. • Post-treatment variations of CBV and K trans-T2 values are predictive factors of OS. • Increased values may justify treatment intensification in these patients.


Subject(s)
Astrocytoma/diagnostic imaging , Brain Neoplasms/diagnostic imaging , Neovascularization, Pathologic/diagnostic imaging , Adult , Aged , Astrocytoma/blood supply , Astrocytoma/pathology , Astrocytoma/therapy , Brain Neoplasms/blood supply , Brain Neoplasms/pathology , Brain Neoplasms/therapy , Cerebrovascular Circulation , Combined Modality Therapy , Female , Humans , Kaplan-Meier Estimate , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neoplasm Grading , Perfusion , Prognosis , Retrospective Studies
13.
Arch Med Res ; 47(8): 623-628, 2016 11.
Article in English | MEDLINE | ID: mdl-28476190

ABSTRACT

BACKGROUND AND AIMS: Childhood acute lymphoblastic leukemia (ALL) is the leading cause of childhood cancer-related deaths worldwide. Multiples studies have shown that ALL seems to be originated by an interaction between environmental and genetic susceptibility factors. The ARID5B polymorphisms are among the most reproducible ALL associated-risk alleles in different populations. The aim of the present study was to examine the contribution of ARID5B, CEBPE, and PIP4K2 risk alleles for the development of ALL in children from Mexico City and Yucatan, Mexico. METHODS: A study was conducted with a total of 761 unrelated subjects. Two hundred eighty five ALL cases (111 from Yucatan and 174 from Mexico City) and 476 healthy subjects. Genotyping included the rs7088318 (PIP4K2A), rs10821936 (ARID5B), rs7089424 (ARID5B) and rs2239633 (CEBPE) polymorphisms. RESULTS: Associations between ALL and rs10821936 and rs7089424 ARID5B SNPs were found (OR = 1.9, 95% CI (1.5-2.4) and OR = 2.0, 95% CI (1.6-2.5), respectively). Moreover, a higher risk was observed in the homozygous risk genotypes of carriers from Mexico City (OR = 3.1, 95% CI (2.0-4.9) and OR 3.1, CI 95% (2.0-4.8), respectively). Otherwise, the rs7088318 (PIP4K2A) and rs2239633 (CEBPE) polymorphisms were not associated with ALL risk. CONCLUSIONS: Our analysis suggests that ARID5B confers risk for childhood ALL in a Mexican population.


Subject(s)
CCAAT-Enhancer-Binding Proteins/genetics , DNA-Binding Proteins/genetics , Phosphotransferases (Alcohol Group Acceptor)/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Transcription Factors/genetics , Adolescent , Alleles , Case-Control Studies , Child , Child, Preschool , Female , Genetic Association Studies , Genetic Predisposition to Disease , Genotype , Heterozygote , Humans , Infant , Male , Mexico , Polymorphism, Single Nucleotide , Risk
14.
Physiol Plant ; 155(3): 296-314, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25582191

ABSTRACT

Jasmonic acid (JA) regulates a wide spectrum of plant biological processes, from plant development to stress defense responses. The role of JA in plant response to salt stress is scarcely known, and even less known is the specific response in root, the main plant organ responsible for ionic uptake and transport to the shoot. Here we report the characterization of the first tomato (Solanum lycopersicum) mutant, named res (restored cell structure by salinity), that accumulates JA in roots prior to exposure to stress. The res tomato mutant presented remarkable growth inhibition and displayed important morphological alterations and cellular disorganization in roots and leaves under control conditions, while these alterations disappeared when the res mutant plants were grown under salt stress. Reciprocal grafting between res and wild type (WT) (tomato cv. Moneymaker) indicated that the main organ responsible for the development of alterations was the root. The JA-signaling pathway is activated in res roots prior to stress, with transcripts levels being even higher in control condition than in salinity. Future studies on this mutant will provide significant advances in the knowledge of JA role in root in salt-stress tolerance response, as well as in the energy trade-off between plant growth and response to stress.


Subject(s)
Cyclopentanes/metabolism , Mutation , Oxylipins/metabolism , Plant Roots/metabolism , Solanum lycopersicum/genetics , Solanum lycopersicum/metabolism , Gene Expression Regulation, Plant , Solanum lycopersicum/cytology , Plant Cells/metabolism , Plant Cells/ultrastructure , Plant Leaves/physiology , Plant Roots/genetics , Potassium/metabolism , Salinity , Salt Tolerance/physiology , Signal Transduction
15.
New Phytol ; 205(1): 216-39, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25187269

ABSTRACT

In this study, we investigated the cellular and molecular mechanisms that regulate salt acclimation. The main objective was to obtain new insights into the molecular mechanisms that control salt acclimation. Therefore, we carried out a multidisciplinary study using proteomic, transcriptomic, subcellular and physiological techniques. We obtained a Nicotiana tabacum BY-2 cell line acclimated to be grown at 258 mM NaCl as a model for this study. The proteomic and transcriptomic data indicate that the molecular response to stress (chaperones, defence proteins, etc.) is highly induced in these salt-acclimated cells. The subcellular results show that salt induces sodium compartmentalization in the cell vacuoles and seems to be mediated by vesicle trafficking in tobacco salt-acclimated cells. Our results demonstrate that abscisic acid (ABA) and proline metabolism are crucial in the cellular signalling of salt acclimation, probably regulating reactive oxygen species (ROS) production in the mitochondria. ROS may act as a retrograde signal, regulating the cell response. The network of endoplasmic reticulum and Golgi apparatus is highly altered in salt-acclimated cells. The molecular and subcellular analysis suggests that the unfolded protein response is induced in salt-acclimated cells. Finally, we propose that this mechanism may mediate cell death in salt-acclimated cells.


Subject(s)
Acclimatization/drug effects , Intracellular Membranes/metabolism , Mitochondria/metabolism , Nicotiana/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Sodium Chloride/pharmacology , Transport Vesicles/metabolism , Abscisic Acid/metabolism , Apoptosis/drug effects , Apoptosis/genetics , Caspases/metabolism , Cell Line , Fluorescence , Gene Expression Regulation, Plant/drug effects , Glutathione/metabolism , Hydrogen Peroxide/metabolism , Intracellular Membranes/drug effects , Intracellular Membranes/ultrastructure , Malondialdehyde/metabolism , Mitochondria/drug effects , Mitochondria/ultrastructure , Plant Proteins/genetics , Plant Proteins/metabolism , Proline/metabolism , Proteome/metabolism , Salt Tolerance , Sodium/metabolism , Subcellular Fractions/drug effects , Subcellular Fractions/metabolism , Nicotiana/cytology , Nicotiana/genetics , Nicotiana/ultrastructure , Transcriptome/genetics , Transport Vesicles/drug effects , Transport Vesicles/ultrastructure
16.
Plant Biotechnol J ; 12(7): 903-13, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24754628

ABSTRACT

Ectopic cystatin expression has long been used in plant pest management, but the cysteine protease, targets of these inhibitors, might also have important functions in the control of plant lifespan and stress tolerance that remain poorly characterized. We therefore characterized the effects of expression of the rice cystatin, oryzacystatin-I (OCI), on the growth, development and stress tolerance of crop (soybean) and model (Arabidopsis thaliana) plants. Ectopic OCI expression in soybean enhanced shoot branching and leaf chlorophyll accumulation at later stages of vegetative development and enhanced seed protein contents and decreased the abundance of mRNAs encoding strigolactone synthesis enzymes. The OCI-expressing A. thaliana showed a slow-growth phenotype, with increased leaf numbers and enhanced shoot branching at flowering. The OCI-dependent inhibition of cysteine proteases enhanced drought tolerance in soybean and A. thaliana, photosynthetic CO2 assimilation being much less sensitive to drought-induced inhibition in the OCI-expressing soybean lines. Ectopic OCI expression or treatment with the cysteine protease inhibitor E64 increased lateral root densities in A. thaliana. E64 treatment also increased lateral root densities in the max2-1 mutants that are defective in strigolactone signalling, but not in the max3-9 mutants that are defective in strigolactone synthesis. Taken together, these data provide evidence that OCI-inhibited cysteine proteases participate in the control of growth and stress tolerance through effects on strigolactones. We conclude that cysteine proteases are important targets for manipulation of plant growth, development and stress tolerance, and also seed quality traits.


Subject(s)
Arabidopsis/genetics , Cystatins/genetics , Glycine max/genetics , Lactones/metabolism , Plant Proteins/genetics , Stress, Physiological/genetics , Arabidopsis/metabolism , Arabidopsis/physiology , Carbon Dioxide/metabolism , Chlorophyll/metabolism , Cystatins/metabolism , Cystatins/physiology , Droughts , Oryza/genetics , Phenotype , Plant Proteins/metabolism , Plant Proteins/physiology , Seeds/genetics , Seeds/metabolism , Seeds/physiology , Glycine max/metabolism , Glycine max/physiology
17.
J Exp Bot ; 65(13): 3513-23, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24510939

ABSTRACT

Succulence and leaf thickness are important anatomical traits in CAM plants, resulting from the presence of large vacuoles to store organic acids accumulated overnight. A higher degree of succulence can result in a reduction in intercellular air space which constrains internal conductance to CO2. Thus, succulence presents a trade-off between the optimal anatomy for CAM and the internal structure ideal for direct C3 photosynthesis. This study examined how plasticity for the reversible engagement of CAM in the genus Clusia could be accommodated by leaf anatomical traits that could facilitate high nocturnal PEPC activity without compromising the direct day-time uptake of CO2 via Rubisco. Nine species of Clusia ranging from constitutive C3 through C3/CAM intermediates to constitutive CAM were compared in terms of leaf gas exchange, succulence, specific leaf area, and a range of leaf anatomical traits (% intercellular air space (IAS), length of mesophyll surface exposed to IAS per unit area, cell size, stomatal density/size). Relative abundances of PEPC and Rubisco proteins in different leaf tissues of a C3 and a CAM-performing species of Clusia were determined using immunogold labelling. The results indicate that the relatively well-aerated spongy mesophyll of Clusia helps to optimize direct C3-mediated CO2 fixation, whilst enlarged palisade cells accommodate the potential for C4 carboxylation and nocturnal storage of organic acids. The findings provide insight on the optimal leaf anatomy that could accommodate the bioengineering of inducible CAM into C3 crops as a means of improving water use efficiency without incurring detrimental consequences for direct C3-mediated photosynthesis.


Subject(s)
Carbon Dioxide/metabolism , Clusia/anatomy & histology , Photosynthesis , Plant Leaves/anatomy & histology , Plant Transpiration , Water/metabolism , Clusia/physiology , Light , Mesophyll Cells , Phenotype , Phosphoenolpyruvate Carboxylase/metabolism , Plant Leaves/physiology , Plant Proteins/metabolism , Plant Stomata/anatomy & histology , Plant Stomata/physiology , Ribulose-Bisphosphate Carboxylase/metabolism , Trees
18.
J Plant Physiol ; 171(5): 64-75, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-24484959

ABSTRACT

Adaptation to salinity of a semi-arid inhabitant plant, henna, is studied. The salt tolerance mechanisms are evaluated in the belief that gas exchange (water vapor and CO2) should play a key role on its adaptation to salt stress because of the strong evaporation conditions and soil water deficit in its natural area of distribution. We grow henna plants hydroponically under controlled climate conditions and expose them to control (0mM NaCl), and two levels of salinity; medium (75mM NaCl) and high (150mM NaCl). Relative growth rate (RGR), biomass production, whole plant and leaf structure and ultrastructure adaptation, gas exchange, chlorophyll fluorescence, nutrients location in leaf tissue and its balance in the plant are studied. RGR and total biomass decreased as NaCl concentration increased in the nutrient solution. At 75mM NaCl root biomass was not affected by salinity and RGR reached similar values to control plants at the end of the experiment. At this salinity level henna plant responded to salinity decreasing shoot to root ratio, increasing leaf specific mass (LSM) and intrinsic water use efficiency (iWUE), and accumulating high concentrations of Na(+) and Cl(-) in leaves and root. At 150mM NaCl growth was severely reduced but plants reached the reproductive phase. At this salinity level, no further decrease in shoot to root ratio or increase in LSM was observed, but plants increased iWUE, maintaining water status and leaf and root Na(+) and Cl(-) concentrations were lower than expected. Moreover, plants at 150mM NaCl reallocated carbon to the root at the expense of the shoot. The effective PSII quantum yield [Y(II)] and the quantum yield of non-regulated energy dissipation [Y(NO)] were recovered over time of exposure to salinity. Overall, iWUE seems to be determinant in the adaptation of henna plant to high salinity level, when morphological adaptation fails.


Subject(s)
Adaptation, Physiological , Lawsonia Plant/physiology , Salt Tolerance , Sodium Chloride/metabolism , Water/metabolism , Desert Climate , Electron Probe Microanalysis , Lawsonia Plant/ultrastructure , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Optical Imaging , Plant Leaves/metabolism , Plant Leaves/ultrastructure , Plant Roots/metabolism , Tunisia
20.
Plant Sci ; 201-202: 1-11, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23352398

ABSTRACT

Carnation (Dianthus caryophyllus L.) is one of the fifth most important ornamental species worldwide. Many desirable plant characteristics, such as big size, adaptation under stress, and intra or interspecific hybridization capability, are dependent on plant ploidy level. We optimized a quick flow cytometry method for DNA content determination in wild and cultivated carnation samples that allowed a systematic evaluation of ploidy levels in Dianthus species. The DNA content of different carnation cultivars and wild Dianthus species was determined using internal reference standards. The precise characterization of ploidy, endoreduplication and C-value of D. caryophyllus 'Master' makes it a suitable standard cultivar for ploidy level determination in other carnation cultivars. Mixoploidy was rigorously characterized in different regions of several organs from D. caryophyllus 'Master', which combined with a detailed morphological description suggested some distinctive developmental traits of this species. Both the number of endoreduplication cycles and the proportion of endopolyploid cells were highly variable in the petals among the cultivars studied, differently to the values found in leaves. Our results suggest a positive correlation between ploidy, cell size and petal size in cultivated carnation, which should be considered in breeding programs aimed to obtain new varieties with large flowers.


Subject(s)
DNA, Plant/genetics , Dianthus/genetics , Endoreduplication , Ploidies , Cell Nucleus/genetics , Cell Size , Dianthus/anatomy & histology , Flow Cytometry/methods , Flowers/genetics , Flowers/ultrastructure , Microscopy, Electron, Scanning , Plant Cells/metabolism , Plant Epidermis/cytology , Plant Leaves/genetics , Plant Leaves/ultrastructure , Plant Stems/cytology , Reference Standards , Species Specificity
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