Publications by authors named "Mena H"

Dysregulated inflammation-resolution programs are associated with atherosclerosis progression. Resolvins, in part, mediate inflammation-resolution programs. Indeed, Resolvin D2 (RvD2) activates GPR18, a G-protein-coupled receptor, and limits plaque progression, though the cellular targets of RvD2 remain unknown.

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Context: Activation of brown adipose tissue (BAT) thermogenesis improves insulin sensitivity and is beneficial in obesity. Emerging evidence indicates that BAT activation increases lipid mediators that play autocrine and endocrine roles to regulate metabolism and inflammation.

Objective: The goal of the study was to determine the relationship between 2 distinct approaches of BAT activation (cold exposure and mirabegron treatment) with lipid mediators in humans.

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Aging is associated with nonresolving inflammation and tissue dysfunction. Resolvin D2 (RvD2) is a proresolving ligand that acts through the G-protein-coupled receptor called GPR18. Unbiased RNA sequencing revealed increased Gpr18 expression in macrophages from old mice, and in livers from elderly humans, which was associated with increased steatosis and fibrosis in middle-aged (MA) and old mice.

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Monocytes (Mo) are highly plastic myeloid cells that differentiate into macrophages after extravasation, playing a pivotal role in the resolution of inflammation and regeneration of injured tissues. Wound-infiltrated monocytes/macrophages are more pro-inflammatory at early time points, while showing anti-inflammatory/pro-reparative phenotypes at later phases, with highly dynamic switching depending on the wound environment. Chronic wounds are often arrested in the inflammatory phase with hampered inflammatory/repair phenotype transition.

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Introduction/objective: Dysregulated inflammation-resolution programs are associated with atherosclerosis progression. Inflammation-resolution is in part mediated by Resolvins, including Resolvin D2 (RvD2). RvD2, which activates a G-protein coupled receptor (GPCR) called GPR18, limits plaque progression.

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Background: The axolotl, is a unique biological model for complete tissue regeneration. Is a neotenic endangered species and is highly susceptible to environmental stress, including infectious disease. In contrast to other amphibians, the axolotl is particularly vulnerable to certain viral infections.

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Obesity induces chronic inflammation resulting in insulin resistance and metabolic disorders. Cold exposure can improve insulin sensitivity in humans and rodents, but the mechanisms have not been fully elucidated. Here, we find that cold resolves obesity-induced inflammation and insulin resistance and improves glucose tolerance in diet-induced obese mice.

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Nonresolving inflammation contributes to the progression of atherosclerosis, a chronic disease characterized by the accumulation of lipid-rich arterial plaques infiltrated with immune cells. In this issue of the JCI, Arnardottir and Thul et al. report that GPR32, a receptor for proresolving lipid mediators including resolvin D1, was decreased in human atherosclerotic lesions and that overexpression of this human receptor in mice reduced lesion area and necrosis of atherosclerotic plaques.

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In this work, we study a mathematical model for the interaction of sensitive-resistant bacteria to antibiotics and analyse the effects of introducing random perturbations to this model. We compare the results of existence and stability of equilibrium solutions between the deterministic and stochastic formulations, and show that the conditions for the bacteria to die out are weaker in the stochastic model. Moreover, a corresponding optimal control problem is formulated for the unperturbed and the perturbed system, where the control variable is prophylaxis.

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Objective: Ceramide 1-phosphate (C1P) is a bioactive sphingolipid highly augmented in damaged tissues. Because of its abilities to stimulate migration of murine bone marrow-derived progenitor cells, it has been suggested that C1P might be involved in tissue regeneration. In the present study, we aimed to investigate whether C1P regulates survival and angiogenic activity of human progenitor cells with great therapeutic potential in regenerative medicine such as endothelial colony-orming cells (ECFCs).

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We investigated the contribution of human platelets to macrophage effector properties in the presence of lipopolysaccharide (LPS), as well as the beneficial effects and time frame for platelet transfusion in septic animals. Our results show that platelets sequester both pro-(TNF-α/IL-6) and anti-(IL-10) inflammatory cytokines released by monocytes. Low LPS concentrations (0.

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Background: We have previously demonstrated that acidic preconditioning of human endothelial colony-forming cells (ECFC) increased proliferation, migration, and tubulogenesis in vitro, and increased their regenerative potential in a murine model of hind limb ischemia without baseline disease. We now analyze whether this strategy is also effective under adverse conditions for vasculogenesis, such as the presence of ischemia-related toxic molecules or diabetes, one of the main target diseases for cell therapy due to their well-known healing impairments.

Methods: Cord blood-derived CD34 cells were seeded in endothelial growth culture medium (EGM2) and ECFC colonies were obtained after 14-21 days.

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Although platelet-rich plasma (PRP) is used as a source of growth factors in regenerative medicine, its effectiveness remains controversial, partially due to the absence of PRP preparation protocols based on the regenerative role of platelets. Here, we aimed to optimise the protocol by analysing PRP angiogenic and regenerative properties. Three optimising strategies were evaluated: dilution, 4 °C pre-incubation, and plasma cryoprecipitate supplementation.

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The mechanisms that link inflammatory responses to cancer development remain a subject of intense investigation, emphasizing the need to better understand the cellular and molecular pathways that create a tumor promoting microenvironment. The myeloid differentiation primary response protein MyD88 acts as a main adaptor molecule for the signaling cascades initiated from Toll-like receptors (TLRs) and the interleukin 1 receptor (IL-1R). MyD88 has been shown to contribute to tumorigenesis in many inflammation-associated cancer models.

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We study linear semi-explicit stochastic operator differential algebraic equations (DAEs) for which the constraint equation is given in an explicit form. In particular, this includes the Stokes equations arising in fluid dynamics. We combine a white noise polynomial chaos expansion approach to include stochastic perturbations with deterministic regularization techniques.

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Current treatment of retinoblastoma involves using the maximum dose of chemotherapy that induces tumor control and is tolerated by patients. The impact of dose and schedule on the cytotoxicity of chemotherapy has not been studied. Our aim was to gain insight into the cytotoxic and antiangiogenic effect of the treatment scheme of chemotherapy used in retinoblastoma by means of different in vitro models and to evaluate potential effects on multi-drug resistance proteins.

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Unlabelled: ESSENTIALS: Extracellular histones are highly augmented in sites of neovessel formation, such as regeneration tissues. We studied histone effect on survival and angiogenic activity of mature and progenitor endothelial cells. Extracellular histones trigger apoptosis and pyroptosis and reduce angiogenesis in vivo and in vitro.

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Purpose: To assess in vitro cytotoxic activity and antiangiogenic effect, ocular and systemic disposition, and toxicity of digoxin in rabbits after intravitreal injection as a potential candidate for retinoblastoma treatment.

Methods: A panel of two retinoblastoma and three endothelial cell types were exposed to increasing concentrations of digoxin in a conventional (72-hour exposure) and metronomic (daily exposure) treatment scheme. Cytotoxicity was defined as the digoxin concentration that killed 50% of the cells (IC50) and was assessed with a vital dye in all cell types.

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Background: Platelets mediate angiogenesis through the secretion of several factors, including the pro-angiogenic vascular endothelial growth factor (VEGF) and the anti-angiogenic endostatin. Although previous findings indicated that these molecules are packed into different alpha-granules and selectively released by specific stimulation of protease-activated receptor (PAR)-1 or PAR-4, recent evidences are against this hypothesis.

Objectives: To elucidate the controversies about the VEGF and endostatin release and the overall angiogenic effect of PARs-stimulated platelets.

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The arenavirus Junin virus (JUNV) is the etiologic agent of Argentine hemorrhagic fever. We characterized the JUNV infection of human peripheral blood-derived plasmacytoid dendritic cells (hpDC), demonstrating that hpDC are susceptible to infection with the C#1 strain (attenuated) and even more susceptible to infection with the P (virulent) JUNV strain. However, hpDC elicited different responses in terms of viability, activation, maturation, and cytokine expression after infection with both JUNV strains.

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Background: To further understand the role of platelets in the pathogenesis of viral infections we explored platelet interaction with Coxsackieviruses B (CVB) 1 and 3. CVB is a group of viruses that cause the majority of human enterovirus-related viral myocarditis; their receptor (CAR) is expressed on the platelet surface and there is a well-characterized CVB3-induced myocarditis murine model.

Methods: Human platelets were infected with CVB1 and 3 and viruses were detected in pellets and in supernatants.

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Solid tumors are infiltrated by immune cells where macrophages and senescent T cells are highly represented. Within the tumor microenvironment, a cross-talk between the infiltrating cells may occur conditioning the characteristic of the in situ immune response. Our previous work showed that tumors induce senescence of T cells, which are powerful suppressors of lympho-proliferation.

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Objective: Acidosis is present in several pathological conditions where vasculogenesis takes place including ischemia, tumor growth and wound healing. We have previously demonstrated that acidosis induces human CD34+ cell apoptosis. Considering that endothelial colony-forming cells (ECFC) are a subpopulation of CD34+ cells and key players in vasculogenesis, in the present study we investigated the effect of acidosis on the survival and functionality of ECFC.

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Acanthamoeba is the most common cause of granulomatous amebic encephalitis, a typically fatal condition that is classically described as indolent and slowly progressive. We report a case of Acanthamoeba encephalitis in a kidney transplant recipient that progressed to death within 3 days of symptom onset and was diagnosed at autopsy. We also review clinical characteristics, treatments, and outcomes of all published cases of Acanthamoeba encephalitis in solid organ transplant (SOT) recipients.

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The Costa Rica national tumour registry was founded in 1976 and nationwide data collection commenced in 1980. Cancer registration is predominantly done by passive methods. The registry contributed data on survival for invasive cancers of breast and cervix and in situ cancer of the cervix registered during 1995-2000.

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