Publications by authors named "Rozenberg G"

Colorectal cancer (CRC) is one of the leading causes of cancer-related death in the United States. Although certain genetic predispositions may contribute to one's risk for developing CRC, dietary and lifestyle factors may play an important role as well. In a recent study in Nature, Dmitrieva-Posocco et al, reveal a potential protective role of the ketogenic diet in colorectal cancer growth and progression.

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The pressure-induced Mott insulator-to-metal transitions are often accompanied by a collapse of magnetic interactions associated with delocalization of 3d electrons and high-spin to low-spin (HS-LS) state transition. Here, we address a long-standing controversy regarding the high-pressure behavior of an archetypal Mott insulator FeBO and show the insufficiency of a standard theoretical approach assuming a conventional HS-LS transition for the description of the electronic properties of the Mott insulators at high pressures. Using high-resolution x-ray diffraction measurements supplemented by Mössbauer spectroscopy up to pressures ~ 150 GPa, we document an unusual electronic state characterized by a "mixed" HS/LS state with a stable abundance ratio realized in the [Formula: see text] crystal structure with a single Fe site within a wide pressure range of ~ 50-106 GPa.

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The metal-insulator transition driven by electronic correlations is one of the most fundamental concepts in condensed matter. In mixed-valence compounds, this transition is often accompanied by charge ordering (CO), resulting in the emergence of complex phases and unusual behaviors. The famous example is the archetypal mixed-valence mineral magnetite, FeO, exhibiting a complex charge-ordering below the Verwey transition, whose nature has been a subject of long-time debates.

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Experiments investigating magnetic-field-tuned superconductor-insulator transition (HSIT) mostly focus on two-dimensional material systems where the transition and its proximate ground-state phases, often exhibit features that are seemingly at odds with the expected behavior. Here we present a complementary study of a three-dimensional pressure-packed amorphous indium-oxide (InOx) powder where granularity controls the HSIT. Above a low threshold pressure of ∼0.

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Introduction: Hydroxychloroquine (HCQ) emerged early in the course of the coronavirus disease 2019 (COVID-19) pandemic as a possible drug with potential therapeutic and prophylactic benefits. It was quickly adopted in China, Europe, and the USA. We systematically reviewed the existing clinical evidence of HCQ use for the prevention and treatment of COVID-19.

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The relationship between the ecological adaptive strategies of some halophyte groups and their metabolism has been demonstrated; this correlation determines their competitive capabilities and place in the ecosystem. The features of the content of total and membrane lipids, chlorophylls, carotenoids, and membrane and water-soluble proteins, as well as the level of lipid peroxidation, hydration of photosynthetic organs, and sodium accumulation in euhalophytes, crynohalophytes, and glycohalophytes, which are confined to different levels of soil salinity, have been established.

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Mechanisms for human sinoatrial node (SAN) dysfunction are poorly understood and whether human SAN excitability requires voltage-gated sodium channels (Nav) remains controversial. Here, we report that neuronal (n)Nav blockade and selective nNav1.6 blockade during high-resolution optical mapping in explanted human hearts depress intranodal SAN conduction, which worsens during autonomic stimulation and overdrive suppression to conduction failure.

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Structural and electronic transformation taking place in α-FeOOH goethite have been studied by Fe K-edge x-ray absorption spectroscopy at pressures up to 50 GPa. These studies have shown the symmetrization of FeO octahedra coinciding with the Fe high to low spin transition at pressure above ~45 GPa. Our data are in excellent agreement with the results of recent single crystal XRD and Mössbauer spectroscopy studies (Xu et al 2013 Phys.

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Immediate and long-term recalls of a pre-travel consultation are suboptimal. We aimed to assess the role of online consultation for travellers. We randomized travellers into two study groups.

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Tumors are fibrotic and characterized by abundant, remodeled, and cross-linked collagen that stiffens the extracellular matrix stroma. The stiffened collagenous stroma fosters malignant transformation of the tissue by increasing tumor cell tension to promote focal adhesion formation and potentiate growth factor receptor signaling through kinase. Importantly, collagen cross-linking requires fibronectin (FN).

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These guidelines provide information on how to reliably and consistently report abnormal red blood cells, white blood cells and platelets using manual microscopy. Grading of abnormal cells, nomenclature and a brief description of the cells are provided. It is important that all countries in the world use consistent reporting of blood cells.

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Abstract-Phenomena having the property of a scale invariance (that is, maintaining invariable structure in certain range of scales) are typical for biosystems of different levels. In this review, main manifestations of the scale-invariant phenomena at different levels of biological organization (including ontogenetic aspects) are stated, and the reasons of such wide distribution of fractal structures in biology are discussed. Almost all biological systems can be described in terms of synergetics as open nonequilibrium systems that exist due to substance and energy flow passing through them.

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Under high pressures the hydrogen bonds were predicted to transform from a highly asymmetric soft O-H···O to a symmetric rigid configuration in which the proton lies midway between the two oxygen atoms. Despite four decades of research on hydroxyl containing compounds, pressure induced hydrogen bond symmetrization remains elusive. Following single crystal x-ray diffraction, Mössbauer and Raman spectroscopy measurements supported by ab initio calculations, we report the H-bonds symmetrization in iron oxyhydroxide, FeOOH, resulting from the Fe(3+) high-to-low spin crossover at above 45 GPa.

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The principles and methods of fractal analysis of the species structure of freshwater phytoplankton, zooplankton, and macrozoobenthos communities of plain water reservoirs and urban waterbodies are discussed. The theoretical foundation and experimental verification are provided for the authors' concept of self-similar (quasi-fractal) nature of the species structure of communities. According to this concept, the adequate mathematical image of species richness accumulation with growing sampling effort is quasi-monofractals, while the generalized geometric image of the species structure of the community is a multifractal spectrum.

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Loss of p16(INK4a)-RB and ARF-p53 tumor suppressor pathways, as well as activation of RAS-RAF signaling, is seen in a majority of human melanomas. Although heterozygous germline mutations of p16(INK4a) are associated with familial melanoma, most melanomas result from somatic genetic events: often p16(INK4a) loss and N-RAS or B-RAF mutational activation, with a minority possessing alternative genetic alterations such as activating mutations in K-RAS and/or p53 inactivation. To generate a murine model of melanoma featuring some of these somatic genetic events, we engineered a novel conditional p16(INK4a)-null allele and combined this allele with a melanocyte-specific, inducible CRE recombinase strain, a conditional p53-null allele and a loxP-stop-loxP activatable oncogenic K-Ras allele.

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Melanoma is the most lethal skin tumor in large part because of a propensity for early metastasis. Good models of this most clinically relevant feature of melanoma are lacking. Here, we report the development of an in-vivo model of metastasis that relies on orthotopic injection of green fluorescent protein-tagged lines in immunodeficient mice, serial intravital imaging of tumor progression, and quantification of distant spread by two-photon laser scanning microscopy, immunohistochemistry, and real-time PCR analysis.

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Two approaches are suggested for describing taxic diversity as a fractal, or self-similar, object. One of them called "sampling approach" is based on necessity of taking into account the sampling process and on proceeding from the real ecological practice of exploration of the community structure. Verification of this approach is fulfilled using a multifractal analysis of the generic diversity of vascular plants of the National Park "Samarskaya Luka".

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TbBaCo_{2}O_{5.48} has been studied by high-pressure synchrotron x-ray diffraction together with resistivity measurements as a function of temperature and pressure. It was found that under pressure a structural phase transition takes place corroborating with a sluggish insulator-to-metal transition.

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Background: Programmed DNA elimination and reorganization frequently occur during cellular differentiation. Development of the somatic macronucleus in some ciliates presents an extreme case, involving excision of internal eliminated sequences (IESs) that interrupt coding DNA segments (macronuclear destined sequences, MDSs), as well as removal of transposon-like elements and extensive genome fragmentation, leading to 98% genome reduction in Stylonychia lemnae. Approximately 20-30% of the genes are estimated to be scrambled in the germline micronucleus, with coding segment order permuted and present in either orientation on micronuclear chromosomes.

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