Publications by authors named "Perez-Gonzalez C"

Panama, located in the heart of the Mesoamerican hotspot, harbors an extraordinary species diversity across the Tree of Life. The Collembola species of the genus play an important role in soil biological processes such as decomposition, being used to monitor soil health and functional parameters. However, the limitation of morphological characters and molecular resources hampers the evaluation of local soil diversity.

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Stem cells perceive and respond to biochemical and physical signals to maintain homeostasis. Yet, it remains unclear how stem cells sense mechanical signals from their niche in vivo. In this work, we investigated the roles of PIEZO mechanosensitive channels in the intestinal stem cell (ISC) niche.

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Milk adulteration presents substantial challenges in the food industry, prompting the need for efficient detection methods. This study introduces a potentiometric electronic tongue for rapid and accurate detection of milk adulteration. Using polymeric membranes with various integrated additives, the electronic tongue distinguished between different milk types and detected common adulterants.

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Organisms whose early life stages are environmentally sensitive produce offspring within a relatively narrow range of suitable abiotic conditions. In reptiles, development rate and survival are often maximized if incubation temperatures remain under 31°C, though this upper bound may vary within and among species. We addressed this expectation by comparing responses to egg incubation at 30°C versus 33°C in congeneric turtle species pairs with broad syntopic geographic distributions.

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Cells within a tumor interact by generating, transmitting, and sensing mechanical forces. Among all the cells of the tumor microenvironment, cancer-associated fibroblasts (CAFs) are a paradigmatic example of mechanical communication. In different steps of tumor progression, CAFs pull and push on cancer cells, regulating cancer cell migration, invasion, compartmentalization, and signaling.

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Morphogenesis and cell state transitions must be coordinated in time and space to produce a functional tissue. An excellent paradigm to understand the coupling of these processes is mammalian hair follicle development, which is initiated by the formation of an epithelial invagination-termed placode-that coincides with the emergence of a designated hair follicle stem cell population. The mechanisms directing the deformation of the epithelium, cell state transitions and physical compartmentalization of the placode are unknown.

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Background: Electronic tongues have been widely used to analyze wines. However, owing to the complexity of the matrix, the problem is not completely solved and further improvements are required.

Results: A high-performance potentiometric bioelectronic tongue (bio-ET) specifically devoted to the assessment of wine components is presented.

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During tumor progression, cancer-associated fibroblasts (CAFs) accumulate in tumors and produce an excessive extracellular matrix (ECM), forming a capsule that enwraps cancer cells. This capsule acts as a barrier that restricts tumor growth leading to the buildup of intratumoral pressure. Combining genetic and physical manipulations in vivo with microfabrication and force measurements in vitro, we found that the CAFs capsule is not a passive barrier but instead actively compresses cancer cells using actomyosin contractility.

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Important bacterial pathogens such as Pseudomonas aeruginosa produce several exoproducts such as siderophores, degradative enzymes, biosurfactants, and exopolysaccharides that are used extracellularly, benefiting all members of the population, hence being public goods. Since the production of public goods is a cooperative trait, it is in principle susceptible to cheating by individuals in the population who do not invest in their production, but use their benefits, hence increasing their fitness at the expense of the cooperators' fitness. Among the most studied virulence factors susceptible to cheating are siderophores and exoproteases, with several studies in vitro and some in animal infection models.

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Background: International migration is increasing steadily worldwide. In Chile 4.4% of its population are migrants.

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The statistical inference of multi-component reliability stress-strength system with nonidentical-component strengths is considered for the modified Weibull extension distribution in the presence of progressive censoring samples. For this aim, we study the estimation of multi-component reliability parameter in classical and Bayesian inference. So we derive some point and interval estimates such as maximum likelihood estimation, asymptotic confidence intervals, uniformly minimum variance unbiased estimation, approximate and exact Bayes estimation and highest posterior density intervals.

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The microenvironment plays an essential role in tumor development and metastatic progression. Here, we describe a simple and rapid protocol to generate tumors in mice using colon cancer cell lines or tumoroids in the correct microenvironment, colonic mucosa. We also detail steps for monitoring the growth of the primary tumor in real time using colonoscopy or in vivo imaging system, as well as monitoring metastasis development.

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Alzheimer's disease (AD) is a progressive neurodegenerative disease affecting cognitive and memory abilities and is believed to be linked to the formation and accumulation of neurotoxic aggregates of the Amyloid-β peptide (Aβ). In particular, it is the formation of soluble pre-fibrillar oligomers within the early stage of Aβ aggregation which is thought to represent a key step in the development of AD, thus underlining the interest in characterizing the aggregation process and the nature of these aggregates. In this context, fluorescence correlation spectroscopy (FCS) has emerged as a valuable alternative for the study of these systems in solution.

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Several factors present in the extracellular environment regulate epithelial cell adhesion and dynamics. Among them, growth factors such as EGF, upon binding to their receptors at the cell surface, get internalized and directly activate the acto-myosin machinery. In this study we present the effects of EGF on the contractility of epithelial cancer cell colonies in confined geometry of different sizes.

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Centrosome amplification, the presence of more than two centrosomes in a cell is a common feature of most human cancer cell lines. However, little is known about centrosome numbers in human cancers and whether amplification or other numerical aberrations are frequently present. To address this question, we have analyzed a large cohort of primary human epithelial ovarian cancers (EOCs) from 100 patients.

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Health care teams are most effective at addressing complex problems and improving health outcomes for underserved populations when team members bring diverse life experiences and perspectives to the effort. With rates of visual impairment expected to increase in the United States by 2050, especially among minority populations, diversification of the ophthalmology workforce will be critical in reducing disparities in access to and quality of vision health care. Currently, ophthalmology is less diverse with respect to race, ethnicity, and gender than graduating medical classes and other medical specialties, as well as the general US population.

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Article Synopsis
  • The physical properties of the cellular microenvironment, especially in deformable collagen-I networks, play a critical role in cell migration dynamics, even when there is no apparent intrinsic directionality in the cells themselves.
  • Cell clusters can create temporary gradients in collagen density and alignment through the viscoelastic behavior of the surrounding network, leading to persistent collective migration.
  • Experiments reveal that changes in the network's physical characteristics, such as crosslinking or altering cluster size, affect migration persistence by impacting network deformation and the distribution of forces during movement.
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Herein, we describe an approach for the on-demand disassembly of dimeric peptides using a palladium-mediated cleavage of a designed self-immolative linker. The utility of the strategy is demonstrated for the case of dimeric basic regions of ZIP transcription factors. While the dimer binds designed DNA sequences with good affinities, the peptide-DNA complex can be readily dismounted by addition of palladium reagents that trigger the cleavage of the spacer, and the release of unfunctional monomeric peptides.

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The main purpose of social science education is the formation of social thought for the understanding of reality from its critical and creative dimensions and for the intervention and democratic participation of a responsible and committed citizenship; that is, the formation of citizens capable of living democratically with each other and of participating in the social, labor, cultural, and political life of their world, and trying to improve it [...

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Guanine quadruplexes (G4s) are highly polymorphic four-stranded structures formed within guanine-rich DNA and RNA sequences that play a crucial role in biological processes. The recent discovery of the first G4 structures within mitochondrial DNA has led to a small revolution in the field. In particular, the G-rich conserved sequence block II (CSB II) can form different types of G4s that are thought to play a crucial role in replication.

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The dizzying life of the homeostatic intestinal epithelium is governed by a complex interplay between fate, form, force and function. This interplay is beginning to be elucidated thanks to advances in intravital and ex vivo imaging, organoid culture, and biomechanical measurements. Recent discoveries have untangled the intricate organization of the forces that fold the monolayer into crypts and villi, compartmentalize cell types, direct cell migration, and regulate cell identity, proliferation and death.

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Cotranscriptional RNA folding is crucial for the timely control of biological processes, but because of its transient nature, its study has remained challenging. While single-molecule Förster resonance energy transfer (smFRET) is unique to investigate transient RNA structures, its application to cotranscriptional studies has been limited to nonnative systems lacking RNA polymerase (RNAP)-dependent features, which are crucial for gene regulation. Here, we present an approach that enables site-specific labeling and smFRET studies of kilobase-length transcripts within native bacterial complexes.

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Microorganisms are ubiquitous in the environment, and the atmosphere is no exception. However, airborne bacterial communities are some of the least studied. Increasing our knowledge about these communities and how environmental factors shape them is key to understanding disease outbreaks and transmission routes.

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