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Carotenoids produced by bacteria, yeasts, algae and plants inactivate Free Radicals (FR). However, FR may inactivate carotenoids and even turn them into free radicals. Oxidative metabolism is a source of the highly motile Reactive Oxygen Species (ROS). To evaluate carotenoid interactions with ROS, the yeast Rhodotorula mucilaginosa was grown in dextrose (YPD), a fermentative substrate where low rates of oxygen consumption and low carotenoid expression were observed, or in lactate (YPLac), a mitochondrial oxidative-phosphorylation (OxPhos) substrate, which supports high respiratory activity and carotenoid production. ROS were high in YPLac-grown cells and these were unmasked by the carotenoid production-inhibitor diphenylamine (DPA). In contrast, in YPD-grown cells ROS were almost absent. It is proposed that YPLac cells are under oxidative stress. In addition, YPLac-grown cells were more sensitive than YPD-grown cells to menadione (MD), a FR-releasing agent. To test whether carotenoids from cells grown in YPLac had been modified by ROS, carotenoids from each, YPD- and YPLac-grown cells were isolated and added back to cells, evaluating protection from MD. Remarkably, carotenoids extracted from cells grown in YPLac medium inhibited growth, while in contrast extracts from YPD-grown cells were innocuous or mildly protective. Results suggest that carotenoid-synthesis in YPLac-cells is a response to OxPhos-produced ROS. However, upon reacting with FR, carotenoids themselves may be inactivated or even become prooxidant themselves.
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The mitochondrial permeability transition (MPT) pore regulates necrotic cell death following diverse cardiac insults. While the componentry of the pore itself remains controversial, Cyclophilin D (CypD) has been well-established as a positive regulator of pore opening. We have previously identified Complement 1q-binding protein (C1qbp) as a novel CypD-interacting molecule and a negative regulator of MPT-dependent cell death in vitro. However, its effects on the MPT pore and sensitivity to cell death in the heart remain untested. We therefore hypothesized that C1qbp would inhibit MPT in cardiac mitochondria and protect cardiac myocytes against cell death in vivo. To investigate the effects of C1qbp in the myocardium we generated gain- and loss-of-function mice. Transgenic C1qbp overexpression resulted in decreased complex protein expression and reduced mitochondrial respiration and ATP production but MPT was unaffected. In contrast, while C1qbp+/- mice did not exhibit any changes in mitochondrial protein expression, respiration, or ATP, the MPT pore was markedly sensitized to Ca2+ in these animals. Neither overexpression nor depletion of C1qbp significantly affected baseline heart morphology or function at 3 months of age. When subjected to myocardial infarction, C1qbp transgenic mice exhibited similar infarct sizes and cardiac remodeling to non-transgenic mice, consistent with the lack of an effect on MPT. In contrast, cardiac scar formation and dysfunction were significantly increased in the C1qbp+/- mice compared to C1qbp+/+ controls. Our results suggest that C1qbp is required for normal regulation of the MPT pore and mitochondrial function, and influences cardiac remodeling following MI, the latter more likely being independent of C1qbp effects on the MPT pore.
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Mathematics teaching strategies have a positive impact on learning. However, there is a lack of studies on non-traditional approaches to early mathematics education in the specialized scientific literature. In this theoretical framework, a study to connect teaching methodology with the various cognitive processes implicated in learning has been designed. A total of 114 primary school students aged 74 and 84 months who were taught mathematics either with the method called Open Algorithm Based on Numbers or with the more traditional Closed Algorithm Based on Ciphers, participated in the study. After conducting a thorough examination of cognitive processes and early math performance using well-established assessment instruments, a comparative analysis was undertaken to explore the relationship between cognitive predictors of mathematical performance, while considering the mathematics teaching strategies used. Students were distributed according to their level of mathematical competence and teaching methodology and the type of schools (Charter or Public). The results from the multivariate statistical test showed that the teaching strategy was inconclusive for most of the cognitive factors studied. Significant differences according to mathematical performance were found for fluid intelligence, verbal short-term memory, and visuospatial working memory. Finally, no significant differences were found in the cognitive variables studied when considering the interaction between the teaching approach, school characteristics, and mathematical achievement as a reference.
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BACKGROUND: Implementing mammogram screening means that clinicians are seeing many breast cancers that will never develop metastases. The purpose of this study was to identify subgroups of breast cancer patients who did not present events related to long-term breast cancer mortality, taking into account diagnosis at breast screening, absence of palpability and axillary involvement, and genomic analysis with PAM50. PATIENTS AND METHODS: To identify them, a retrospective observational study was carried out selecting patients without any palpable tumor and without axillary involvement, and a genomic analysis was performed with PAM50. RESULTS: The probability of distant metastasis-free interval (DMFI) of 337 patients was 0.92 (95% CI, 0.90-0.93) at 20 years and 0.96 (95% CI, 0.92-1.00) in 95 patients (28%) with available PAM50 tests. In 22 (23.15%) luminal A tumors and in 9 (9.47%) luminal B tumors smaller than 1 cm, and in HER2 and basal type tumors, there were no metastatic events (20-year DMFI of 1.00). CONCLUSION: Patients with nonpalpable breast cancer found at screening with negative nodes are at very low risk. It is possible to identify subgroups without metastatic events by determining the intrinsic subtype and tumor size less than 1 cm. Therefore, de-escalation of treatment should be considered.
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The 21st century has seen the launch of new space-borne sensors based on LiDAR (light detection and ranging) technology developed in the second half of the 20th century. Nowadays, these sensors offer novel opportunities for mapping terrain and canopy heights and estimating aboveground biomass (AGB) across local to regional scales. This study aims to analyze the scientific impact of these sensors on large-scale forest mapping to retrieve 3D canopy information, monitor forest degradation, estimate AGB, and model key ecosystem variables such as primary productivity and biodiversity. A worldwide bibliometric analysis of this topic was carried out based on up to 412 publications indexed in the Scopus database during the period 2004-2022. The results showed that the number of published documents increased exponentially in the last five years, coinciding with the commissioning of two new LiDAR space missions: Ice, Cloud, and Land Elevation Satellite (ICESat-2) and Global Ecosystem Dynamics Investigation (GEDI). These missions have been providing data since 2018 and 2019, respectively. The journal that demonstrated the highest productivity in this field was "Remote Sensing" and among the leading contributors, the top five countries in terms of publications were the USA, China, the UK, France, and Germany. The upward trajectory in the number of publications categorizes this subject as a highly trending research topic, particularly in the context of improving forest resource management and participating in global climate treaty frameworks that require monitoring and reporting on forest carbon stocks. In this context, the integration of space-borne data, including imagery, SAR, and LiDAR, is anticipated to steer the trajectory of this research in the upcoming years.
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Diabetes mellitus (DM) is a highly prevalent disease worldwide, estimated to affect 1 in every 11 adults; among them, 90-95% of cases are type 2 diabetes mellitus. This is partly attributed to the surge in the prevalence of obesity, which has reached epidemic proportions since 2008. In these patients, cardiovascular (CV) risk stands as the primary cause of morbidity and mortality, placing a substantial burden on healthcare systems due to the potential for macrovascular and microvascular complications. In this context, leptin, an adipocyte-derived hormone, plays a fundamental role. This hormone is essential for regulating the cellular metabolism and energy balance, controlling inflammatory responses, and maintaining CV system homeostasis. Thus, leptin resistance not only contributes to weight gain but may also lead to increased cardiac inflammation, greater fibrosis, hypertension, and impairment of the cardiac metabolism. Understanding the relationship between leptin resistance and CV risk in obese individuals with type 2 DM (T2DM) could improve the management and prevention of this complication. Therefore, in this narrative review, we will discuss the evidence linking leptin with the presence, severity, and/or prognosis of obesity and T2DM regarding CV disease, aiming to shed light on the potential implications for better management and preventive strategies.
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Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Leptina , Obesidade , Adulto , Humanos , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Leptina/metabolismo , Obesidade/metabolismoRESUMO
INTRODUCTION: Our aim was to investigate the prevalence of atrial fibrillation (AF) and recently diagnosed lung cancer in the outpatient oncology clinic and to describe the clinical profile, management and outcomes of this population. METHODS: Among 6984 patients visited at the outpatient oncology clinics attending lung cancer patients in five university hospitals from 2017 to 2019, all consecutive subjects with recently diagnosed (<1 year) disease and AF were retrospectively selected and events in follow up were registered. RESULTS: A total of 269 patients (3.9 % of all attended, 71 ± 8 years, 91 % male) were included. Charlson, CHA2DS2-VASc and HAS-BLED indexes were 6.7 ± 2.9, 2.9 ± 1.5 y 2.5 ± 1.2, respectively. Tumour stage was I, II, III and IV in 11 %, 11 %, 33 % and 45 % of them, respectively. Anticoagulants were prescribed to 226 patients (84 %): direct anticoagulants (n = 99;44 %), low molecular weight heparins (n = 69;30 %) and vitamin K antagonists (n = 58;26 %). After 46 months of maximum follow-up, 186 patients died (69 %). Cumulative incidences of events at 3 years were 3.3 ± 1.3 % for stroke/systemic embolism (n = 7); 8.9 ± 2.2 % for thrombotic events (n = 18); 9.9 ± 2.6 % for major bleeding (n = 16), and 15.9 ± 3,0 % for cardiovascular events (n = 33). In patients with early stages of cancer (I-II), 2-year mortality was significantly higher in those with cardiovascular events or major bleeding (85 % vs 25 %, p = 0.01). CONCLUSION: Nearly 4 % or all outpatients in the oncology clinic attending lung cancer present recently diagnosed disease and AF. Major bleeding and cardiovascular event rates are high in this population, with an impact on mortality in early stages of cancer.
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Fibrilação Atrial , Neoplasias Pulmonares , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Pacientes Ambulatoriais , Estudos Retrospectivos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/induzido quimicamente , Hemorragia/induzido quimicamente , Acidente Vascular Cerebral/epidemiologia , Anticoagulantes/uso terapêutico , Fatores de Risco , Medição de RiscoRESUMO
BACKGROUND: The aneurysmal bone cyst is a benign neoplasm that tends to form the appearance of a mass with a bony septum that forms cavities with blood inside. It is estimated to represent 1% of bone tumours and has an incidence of 0.14 per 100,000 people worldwide. Current publications have not shown a multidisciplinary approach that can benefit patients, mainly in the functionality and quality of the management approach. OBJECTIVE: Describe the multidisciplinary approach and the benefits of quality of life and functionality in this diagnosis. CASE: A paediatric patient was diagnosed with an aneurysmal bone cyst located in the cervical spine, which initially manifested with muscle pain, enlargement of the posterior cervical region, and difficulty in performing arcs of movement. He was treated with multidisciplinary management with surgery, embolisation, radiation, and bisphosphonate support. CONCLUSION: The purpose of approaching multidisciplinary management helped to improve the accompanying symptoms that prevented our patient from having an active and quality life. However, more successful cases have not been reported to establish the best therapeutic protocol.
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Plant metabolism is constantly changing and requires input signals for efficient regulation. The mitochondrial calcium uniporter (MCU) couples organellar and cytoplasmic calcium oscillations leading to oxidative metabolism regulation in a vast array of species. In Arabidopsis thaliana, genetic deletion of AtMICU leads to altered mitochondrial calcium handling and ultrastructure. Here we aimed to further assess the consequences upon genetic deletion of AtMICU. Our results confirm that AtMICU safeguards intracellular calcium transport associated with carbohydrate, amino acid, and phytol metabolism modifications. The implications of such alterations are discussed.
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Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Cálcio/metabolismo , Mitocôndrias/metabolismo , Sinalização do Cálcio , Citoplasma/metabolismoRESUMO
Phylogenetic diversity of plant communities can influence the interaction between plants, herbivores, and their natural enemies. Plant communities with phylogenetically distant species tend to present a wide variety of functional traits and ecological niches, which in turn can influence competitive interactions among plants as well as food and habitat quality for herbivores and their natural enemies. To assess some different mechanisms by which phylogenetic diversity of plant communities can influence herbivores and their natural enemies, we established 12 experimental plots of tropical trees with two treatments: high and low phylogenetic diversity. We measured plant growth and anti-herbivore defenses, herbivore foliar damage, and predator activity in seven species that were present in both treatments. We found significant differences in the expression of plant traits as a function of species identity and their life history, but also depending on the phylogenetic context in which they grew. Pioneer species had higher growth and produced more phenolics in plots with high phylogenetic diversity versus plants in plots with low phylogenetic diversity. Accordingly, herbivore damage in these species was greater in plots with low phylogenetic diversity. Finally, predator activity on caterpillar clay models placed on plants was greater within the low phylogenetic diversity treatment, but only for non-myrmecophytic species. These results suggest that plant phylogenetic diversity can influence the expression of growth and defensive traits and further modify the interaction between plants, herbivores, and their natural enemies. However, such effects depend on plant life history and the presence of mutualistic interaction with ants.
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Ecossistema , Plantas , Filogenia , Herbivoria , Desenvolvimento VegetalRESUMO
The study of electroencephalographic (EEG) signals in nonhuman primates has led to important discoveries in neurophysiology and sleep behavior. Several studies have analyzed digital EEG data from primate species with prehensile tails, like the spider monkey, and principal component analysis has led to the identification of new EEG bands and their spatial distribution during sleep and wakefulness in these monkeys. However, the spatial location of the EEG correlations of these new bands during the sleep-wake cycle in the spider monkey has not yet been explored. Thus, the objective of this study was to determine the spatial distribution of EEG correlations in the new bands during wakefulness, rapid eye movement (REM) sleep, and non-REM sleep in this species. EEG signals were obtained from the scalp of six monkeys housed in experimental conditions in a laboratory setting. Regarding the 1-21 Hz band, a significant correlation between left frontal and central regions was recorded during non-REM 2 sleep. In the REM sleep, a significant correlation between these cortical areas was seen in two bands: 1-3 and 3-13 Hz. This reflects a modification of the degree of coupling between the cortical areas studied, associated with the distinct stages of sleep. The intrahemispheric EEG correlation found between left perceptual and motor regions during sleep in the spider monkey could indicate activation of a neural circuit for the processing of environmental information that plays a critical role in monitoring the danger of nocturnal predation.
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Ateles geoffroyi , Atelinae , Animais , Atelinae/fisiologia , Fases do Sono/fisiologia , Sono/fisiologia , Eletroencefalografia/veterináriaRESUMO
BACKGROUND: Radiomics refers to the acquisition of traces of quantitative features that are usually non-perceptible to human vision and are obtained from different imaging techniques and subsequently transformed into high-dimensional data. Diffuse midline gliomas (DMG) represent approximately 20% of pediatric CNS tumors, with a median survival of less than one year after diagnosis. We aimed to identify which radiomics can discriminate DMG tumor regions (viable tumor and peritumoral edema) from equivalent midline normal tissue (EMNT) in patients with the positive H3.F3K27M mutation, which is associated with a worse prognosis. PATIENTS AND METHODS: This was a retrospective study. From a database of 126 DMG patients (children, adolescents, and young adults), only 12 had H3.3K27M mutation and available brain magnetic resonance DICOM file. The MRI T1 post-gadolinium and T2 sequences were uploaded to LIFEx software to post-process and extract radiomic features. Statistical analysis included normal distribution tests and the Mann-Whitney U test performed using IBM SPSS® (Version 27.0.0.1, International Business Machines Corp., Armonk, NY, USA), considering a significant statistical p-value ≤ 0.05. RESULTS: EMNT vs. Tumor: From the T1 sequence 10 radiomics were identified, and 14 radiomics from the T2 sequence, but only one radiomic identified viable tumors in both sequences (p < 0.05) (DISCRETIZED_Q1). Peritumoral edema vs. EMNT: From the T1 sequence, five radiomics were identified, and four radiomics from the T2 sequence. However, four radiomics could discriminate peritumoral edema in both sequences (p < 0.05) (CONVENTIONAL_Kurtosis, CONVENTIONAL_ExcessKurtosis, DISCRETIZED_Kurtosis, and DISCRETIZED_ExcessKurtosis). There were no radiomics useful for distinguishing tumor tissue from peritumoral edema in both sequences. CONCLUSIONS: Less than 5% of the radiomic characteristics identified tumor regions of medical-clinical interest in T1 and T2 sequences of conventional magnetic resonance imaging. The first-order and second-order radiomic features suggest support to investigators and clinicians for careful evaluation for diagnosis, patient classification, and multimodality cancer treatment planning.
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The first conotoxin affecting the voltage-gated potassium channels of the EAG family was identified and characterized from the venom of the vermivorous species Conus spurius from the Gulf of Mexico. This conopeptide, initially named Cs68 and later designated κO-SrVIA, is extremely hydrophobic and comprises 31 amino acid residues, including six Cysteines in the framework VI/VII, and a free C-terminus. It inhibits the currents mediated by two human EAG subtypes, Kv10.1 (IC50 = 1.88 ± 1.08 µM) and Kv11.1 (IC50 = 2.44 ± 1.06 µM), and also the human subtype Kv1.6 (IC50 = 3.6 ± 1.04 µM). Despite its clear effects on potassium channels, it shares a high sequence identity with δ-like-AtVIA and δ-TsVIA. Also, κO-SrVIA is the third conopeptide from the venom of C. spurius with effects on potassium channels, and the seventh conotoxin that blocks Kv1.6 channels.
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Conotoxinas , Caramujo Conus , Canais de Potássio Éter-A-Go-Go , Animais , Humanos , Sequência de Aminoácidos , Conotoxinas/farmacologia , Conotoxinas/química , Caramujo Conus/química , Canais de Potássio Éter-A-Go-Go/efeitos dos fármacos , Canais de Potássio Éter-A-Go-Go/metabolismo , Canais de Potássio Éter-A-Go-Go/toxicidade , Peptídeos/químicaRESUMO
Solvent effects on the UV-vis spectra of 3-hydroxyflavone and other structurally related molecules (3-hydroxychromen-4-one, 3-hydroxy-4-pyrone, and 4-pyrone) have been studied by combining time-dependent density functional theory (TDDFT) and the polarizable continuum method (PCM). Among the first five excited states of the four considered molecules, electronic states of n â π* and π â π* nature appear. In general, the stability of the n â π* states decreases as the π space becomes larger in such a way that only for 4-pyrone and 3-hydroxy-4-pyrone are they the first excited states. In addition, they become less stabilized in ethanol solution than the ground state, and this causes blueshift transitions in solution. The opposite trend is found for the π â π* excited states. They are less energetic with the π-system size and when passing from gas phase to solution. The solvent shift also depends strongly on the size of the π systems and on the formation of an intramolecular hydrogen bond; thus, it decreases when going from 4-pyrone to 3-hydroxyflavone. The performance of the three versions (cLR, cLR2, and IBSF) of the specific-state PCM method in predicting transition energies are compared.
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Venoms from tarantulas contain low molecular weight vasodilatory compounds whose biological action is conceived as part of the envenomation strategy due to its propagative effects. However, some properties of venom-induced vasodilation do not match those described by such compounds, suggesting that other toxins may cooperate with these ones to produce the observed biological effect. Owing to the distribution and function of voltage-gated ion channels in blood vessels, disulfide-rich peptides isolated from venoms of tarantulas could be conceived into potential vasodilatory compounds. However, only two peptides isolated from spider venoms have been investigated so far. This study describes for the first time a subfraction containing inhibitor cystine knot peptides, PrFr-I, obtained from the venom of the tarantula Poecilotheria regalis. This subfraction induced sustained vasodilation in rat aortic rings independent of vascular endothelium and endothelial ion channels. Furthermore, PrFr-I decreased calcium-induced contraction of rat aortic segments and reduced extracellular calcium influx to chromaffin cells by the blockade of L-type voltage-gated calcium channels. This mechanism was unrelated to the activation of potassium channels from vascular smooth muscle, since vasodilation was not affected in the presence of TEA, and PrFr-I did not modify the conductance of the voltage-gated potassium channel Kv10.1. This work proposes a new envenomating function of peptides from venoms of tarantulas, and establishes a new mechanism for venom-induced vasodilation.
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Back in January 2022, an EASL-Lancet Commission on the impact of liver disorders in the European region commissioned by the WHO demonstrated that this condition is, actually, the second leading cause of loss of labor years in Europe after ischemic heart disease (1). This is a very relevant piece of information since this is something that is going to impact the new generations of Europeans unless a significant change is made in public health policies. Despite the advances made over the last few years in hepatitis C virus clearance-understood as a significant reduction of morbidity and mortality associated with Hepatitis B and C viruses-there are still challenges ahead to improve liver health due to the high use of alcohol, and the inseparable triad obesity / diabetes mellitus / metabolic associated fatty liver disease. Also, access to healthcare for several population groups at risk of presenting higher rates of liver disease has become a problem.
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Hepatite C , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepacivirus , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Nível de SaúdeRESUMO
It has been reported that melatonin diminishes rapid eye movement (REM) sleep latency in patients with Alzheimer's disease (AD). Pharmacological studies suggest that melatonin promotes prompt sleep installation through interaction with GABA receptors, and that it is associated with acute suppression of neural electrical activity. Nevertheless, melatonin's effects on electroencephalographic (EEG) activity related to REM sleep onset in AD patients have not been analyzed. Thus, in this pilot study we analyzed the effects of melatonin on EEG activity during the first episode of REM sleep in eight patients treated with 5-mg of fast-release melatonin.During a single-blind, placebo-controlled study, polysomnographic recordings were obtained from frontal, central, temporal, and occipital scalp derivations. REM sleep latency, as well as the relative power (RP) and EEG coherences of six EEG bands, were compared between the placebo and melatonin conditions.Results showed that melatonin intake in AD patients decreased REM sleep onset, and that this was associated with lower RP and coherence of the ß and γ EEG bands.The possibility that the inhibitory GABAergic pathways related to REM sleep generation are well-preserved in mild-to-moderate AD is discussed. We conclude that the short REM sleep onset related to melatonin intake in AD patients is associated with a significant decrease in both RP and EEG coherence, mainly in the fast frequencies.
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Doença de Alzheimer , Melatonina , Humanos , Sono REM , Doença de Alzheimer/tratamento farmacológico , Melatonina/farmacologia , Melatonina/uso terapêutico , Projetos Piloto , Método Simples-Cego , EletroencefalografiaRESUMO
This research presents the findings of a comparative study of mathematical competence among 130 students (M = 54.08 months; SD = 2.57) from vulnerable school contexts in Chile and the Spanish public school system. The study analyses a set of general and specific domain precursors for which evidence of socioeconomic background exists. Using multivariate regression and discriminant analysis techniques, we calculated similarities and differences between groups by comparing these precursors. Significant differences were found between the Spanish and Chilean groups (p < .05); however, no differences were observed in non-symbolic comparison and receptive vocabulary. Possible reasons for the existence and extent of these differences are discussed in terms of socio-cultural and educational contexts.