Publications by authors named "Ponce I"

Article Synopsis
  • Aging leads to functional decline and cognitive impairment, but caloric restriction (CR) can help delay these effects and improve cognitive function in older adults.
  • There is a connection between memory, learning, and the circadian clock, which indicates that timing and regulation are essential for cognitive processes.
  • Research showed that late-onset CR restored circadian rhythms and improved cognitive abilities in aging rats, suggesting that lifestyle changes like CR could preserve brain health as we age.
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While cytostatic chemotherapy targeting DNA is known to induce genotoxicity, leading to cell cycle arrest and cytokine secretion, the impact of these drugs on fibroblast-epithelial cancer cell communication and metabolism remains understudied. Our research focused on human breast fibroblast RMF-621 exposed to nonlethal concentrations of cisplatin and doxorubicin, revealing reduced proliferation, diminished basal and maximal mitochondrial respirations, heightened mitochondrial ROS and lactate production, and elevated MCT4 protein levels. Interestingly, RMF-621 cells enhanced glucose uptake, promoting lactate export.

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Melanin is an essential product that plays an important role in innate immunity in a variety of organisms across the animal kingdom. Melanin synthesis is performed by many organisms using the tyrosine metabolism pathway, a general pathway that utilizes a type-three copper oxidase protein, called PO-candidates (phenoloxidase candidates). While melanin synthesis is well-characterized in organisms like arthropods and humans, it is not as well-understood in non-model organisms such as cnidarians.

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  • This study compares two surgical methods, Hartmann's procedure (HP) and resection with primary anastomosis (RPA), for treating acute left-sided colonic emergencies among 1215 patients from 204 centers globally.
  • Results showed that while HP was the more common treatment (57.3%), RPA was favored for younger patients with fewer health issues and those needing surgery sooner.
  • The study concluded that although HP is still widely used, RPA might be the better option, emphasizing the importance of patient characteristics and surgeon experience in determining treatment choice.
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Background: Significant differences in immune responses, prevalence or susceptibility of diseases and treatment responses have been described between males and females. Despite this, sex-differentiation analysis of the genetic architecture of inflammatory proteins is largely unexplored. We performed sex-stratified meta-analysis after protein quantitative trait loci (pQTL) mapping using inflammatory biomarkers profiled using targeted proteomics (Olink inflammatory panel) of two population-based cohorts of Europeans.

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Agricultural soil salinization, which is often combined with heavy-metal contamination, is an ever-growing problem in the current era of global change. Legumes have a high potential for nitrogen fixation and are ideal crops for the reclamation of degraded soils. Alfalfa () is a valuable forage crop cultivated worldwide.

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The chiral-induced spin selectivity effect (CISS) is a breakthrough phenomenon that has revolutionized the field of electrocatalysis. We report the first study on the electron spin-dependent electrocatalysis for the oxygen reduction reaction, ORR, using iron phthalocyanine, FePc, a well-known molecular catalyst for this reaction. The FePc complex belongs to the non-precious catalysts group, whose active site, FeN4, emulates catalytic centers of biocatalysts such as Cytochrome c.

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  • Spontaneous recovery after a stroke is crucial for neurological improvement, driven by axonal repair mechanisms influenced by certain molecular signals.
  • Researchers accelerated this recovery in rats by administering extracellular vesicles from primary cortical astrocytes, observing significant structural and functional changes over 21 days.
  • The study highlights the potential of astrocytic extracellular vesicles to enhance natural post-stroke recovery, providing both anatomical and functional benefits.
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  • * The agrochemical industry has developed chemicals to combat these nematodes, but their use can harm beneficial organisms and contaminate water supplies.
  • * Biotechnology offers promising solutions through nematophagous fungi like Purpureocillium lilacinum and Pochonia chlamydosporia for biological pest control, yet challenges remain in their mass production and commercial usage due to unpredictable interactions in the ecosystem.
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Breast tumors belong to the type of desmoplastic lesion in which a stiffer tissue structure is a determinant of breast cancer progression and constitutes a risk factor for breast cancer development. It has been proposed that cancer-associated stromal cells (responsible for this fibrotic phenomenon) are able to metabolize glucose via lactate production, which supports the catabolic metabolism of cancer cells. The aim of this work was to investigate the possible functional link between these two processes.

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The rhythm of factors involved in luteal regression is crucial in determining the physiological duration of the oestrous cycle. Given the role of tumour necrosis factor (TNF)-α in luteal function and circadian regulation and that most of the effects of TNF-α are mediated by p55 TNF receptor (TNFRp55), the aims of the present study were to analyse the following during the luteal regression phase in the ovary of mice: (1) whether the pattern of expression of progesterone (P4) and the enzymes involved in the synthesis and degradation of P4 is circadian and endogenous (the rhythm persists in constant conditions, (i.e.

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Trypanosoma cruzi, the causative agent of Chagas' disease survives to DNA damage generated by ROS/RNS inside to their different hosts. In recent eukaryotes, oxidative DNA damage is repaired mainly by the Base Excision Repair (BER) pathway, being essential the apurinic/apyrimidinic endonuclease activity. Using a pTREX-gfp vector, the nucleotide sequence that encodes T.

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Purpose: Pharyngo-amygdalitis is the most common infection caused by Streptococcus pyogenes (S. pyogenes). Reinfection with strains of different M types commonly occurs.

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Background: Aging is a complex and multifactorial biological process that leads to the progressive deterioration of physiological systems, including the circadian system. In addition, oxidative stress has been associated with the aging of the normal brain and the development of late-onset neurodegenerative diseases. Even though, functional weakening of circadian rhythms and antioxidant function has been observed during aging, the mechanisms by which the circadian system signaling and oxidative stress are interrelated have not yet been elucidated.

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FLAP endonucleases (FEN) are involved both in DNA replication and repair by processing DNA intermediaries presenting a nucleotide flap using its phosphodiesterase activity. In spite of these important functions in DNA metabolism, this enzyme was not yet studied in Trypanosomatids. Trypanosoma cruzi, the ethiological agent of Chagas disease, presents two dividing cellular forms (epimastigote and amastigote) and one non-proliferative, infective form (trypomastigote).

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Aging brain undergoes several changes leading to a decline in cognitive functions. Memory and learning-related genes such as Creb, Bdnf and its receptor TrkB, are expressed in different brain regions including prefrontal cortex. Those genes' proteins regulate a wide range of functions such as synaptic plasticity and long-term potentiation.

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We studied the electronic and conductance properties of two thiophene-curcuminoid molecules, 2-thphCCM (1) and 3-thphCCM (2), in which the only structural difference is the position of the sulfur atoms in the thiophene terminal groups. We used electrochemical techniques as well as UV/Vis absorption studies to obtain the values of the HOMO-LUMO band gap energies, showing that molecule 1 has lower values than 2. Theoretical calculations show the same trend.

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Trypanosoma cruzi, the etiological agent of Chagas' disease, presents three cellular forms (trypomastigotes, epimastigotes and amastigotes), all of which are submitted to oxidative species in its hosts. However, T. cruzi is able to resist oxidative stress suggesting a high efficiency of its DNA repair machinery.

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Using scanning tunneling microscope break-junction experiments and a new first-principles approach to conductance calculations, we report and explain low-bias charge transport behavior of four types of metal-porphyrin-gold molecular junctions. A nonequilibrium Green's function approach based on self-energy corrected density functional theory and optimally tuned range-separated hybrid functionals is developed and used to understand experimental trends quantitatively. Importantly, due to the localized d states of the porphyrin molecules, hybrid functionals are essential for explaining measurements; standard semilocal functionals yield qualitatively incorrect results.

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Trypanosoma cruzi is the etiological agent of Chagas disease. The parasite has to overcome oxidative damage by ROS/RNS all along its life cycle to survive and to establish a chronic infection. We propose that T.

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Purpose: The goal of this work is to increase the spatial resolution of training data, used by reconstruction methods such as k-t SENSE in order to calculate the missing data in a series of dynamic images, without compromising their temporal resolution or acquisition time.

Theory: The k-t SENSE method allows dynamic imaging at high acceleration factors with high reconstruction quality. However, the low resolution training data required by k-t SENSE may cause undesired temporal filtering effects in the reconstructed images.

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Examples of hormonal phase-shifting of circadian gene expression began to emerge a few years ago. Vitamin A fulfills a hormonal function by binding of retinoic acid to its nuclear receptors, RARs and RXRs. We found retinoid- as well as clock-responsive sites on regulatory regions of Glutathione reductase (GR) and Glutathione peroxidase (GPx) genes.

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An endogenous time-keeping mechanism controls circadian biological rhythms in mammals. Previously, we showed that vitamin A deficiency modifies clock BMAL1 and PER1 as well as BDNF and neurogranin daily rhythmicity in the rat hippocampus when animals are maintained under 12-h-light:12-h-dark conditions. Retinoic acid nuclear receptors, retinoic acid receptors (RARs) and retinoid X receptors (RXRs), have been detected in the same brain area.

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The circadian expression of clock and clock-controlled cognition-related genes in the hippocampus would be essential to achieve an optimal daily cognitive performance. There is some evidence that retinoid nuclear receptors (RARs and RXRs) can regulate circadian gene expression in different tissues. In this study, Holtzman male rats from control and vitamin A-deficient groups were sacrificed throughout a 24-h period and hippocampus samples were isolated every 4 or 5 h.

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Autocalibrated parallel MRI methods such as TSENSE or k-t SENSE have been presented for dynamic imaging studies as they are able to provide images with high temporal resolution. One key element of these techniques is the temporal averaging of the undersampled raw data to obtain an unaliased image. This image represents the temporal average (also known as direct current, DC) and is used to derive the reconstruction parameters.

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