153 research outputs found

    Neuroradiological findings in Alagille syndrome

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    Alagille syndrome (ALGS) is a multisystemic disease caused by mutations in genes of Notch pathway, which regulates embryonic cell differentiation and angiogenesis. Clinically, ALGS is characterized by cholestasis, cardiac defects, characteristic facial features, skeletal and ophthalmologic abnormalities. The aim of this review is to illustrate neuroradiological findings in ALGS, which are less well-known and prevalent, including cerebrovascular anomalies (such as aneurysms, dolichoectasia, Moyamoya syndrome and venous peculiarities), Chiari 1 malformation, craniosynostosis, intracranial hypertension, and vertebral anomalies (namely butterfly vertebra, hemivertebra, and craniocervical junction anomalies). Rarer cerebral midline malformations and temporal bone anomalies have also been described

    Smoke, alcohol and drug addiction and male fertility

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    In recent decades, the decline in human fertility has become increasingly more worrying: while therapeutic interventions might help, they are vexing for the couple and often burdened with high failure rates and costs. Prevention is the most successful approach to fertility disorders in males and females alike. We performed a literature review on three of the most common unhealthy habits - tobacco, alcohol and drug addiction - and their reported effects on male fertility. Tobacco smoking is remarkably common in most first-world countries; despite a progressive decline in the US, recent reports suggest a prevalence of more than 30% in subjects of reproductive age - a disturbing perspective, given the well-known ill-effects on reproductive and sexual function as well as general health. Alcohol consumption is often considered socially acceptable, but its negative effects on gonadal function have been consistently reported in the last 30 years. Several studies have reported a variety of negative effects on male fertility following drug abuse - a worrying phenomenon, as illicit drug consumption is on the rise, most notably in younger subjects. While evidence in these regards is still far from solid, mostly as a result of several confounding factors, it is safe to assume that cessation of tobacco smoking, alcohol consumption and recreational drug addiction might represent the best course of action for any couple trying to achieve pregnancy

    Androgen modulation of pro-inflammatory and antiinflammatory cytokines during preadipocyte differentiation

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    Background: Macrophages and adipocytes contribute to release of cytokines resulting in the chronic inflammatory profile of the metabolic syndrome. The local increase of proinflammatory cytokines impairs adipogenesis, resulting in formation of dysfunctional adipocytes that are unable to store and handle lipids. The altered lipid fluxes in/from adipocytes affect whole-body metabolism. We investigated the role of androgens on adipocyte-derived proinflammatory and anti-inflammatory cytokines during preadipocyte differentiation. Materials and methods: Various differentiation methods were used to obtain full conversion of 3T3-L1 into mature adipocytes. The degree of adipocyte conversion in the presence/absence of dihydrotestosterone (DHT) was analyzed by measuring intracellular triglycerides (Oil Red O staining). The effects of DHT administration on interleukin 1Β (IL-1Β), IL-2, IL-6, IL-10, IL-12, interferon γ (IFNΓ) and tumor necrosis factor α (TNFα) secretion was measured at days 0, 4, 6 and 8 of differentiation using the SearchLight multiplex protein array. Results: DHT regulates a number of cytokines in committed and mature 3T3-L1 adipocytes. IL-1Β and TNFα were readily suppressed at the very early stages of differentiation. IFNΓ release was inhibited at day 4, but the effect was no longer detectable on day 8. IL-6 and IL-12 were significantly reduced at day 8 of differentiation. Conversely, the differentiation-dependent increase of IL-2 and IL-10 was further stimulated by DHT since day 0. Conclusions: We provide evidence that androgens promote an anti-inflammatory profile that parallels the acquisition of a functional adipocyte phenotype. The crosstalk between androgens, adipocyte-derived mediators of inflammation and intracellular lipid fluxes could have profound implications on metabolism of men with obesity and metabolic syndrome. © 2010, by Walter de Gruyter Berlin New York. All rights reserved

    Cooperative binding of the cationic porphyrin tris-t4 enhances catalytic activity of 20s proteasome unveiling a complex distribution of functional states

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    The present study provides new evidence that cationic porphyrins may be considered as tunable platforms to interfere with the structural “key code” present on the 20S proteasome α-rings and, by consequence, with its catalytic activity. Here, we describe the functional and conformational effects on the 20S proteasome induced by the cooperative binding of the tri-cationic 5-(phenyl)-10,15,20-(tri N-methyl-4-pyridyl) porphyrin (Tris-T4). Our integrated kinetic, NMR, and in silico analysis allowed us to disclose a complex effect on the 20S catalytic activity depending on substrate/porphyrin concentration. The analysis of the kinetic data shows that Tris-T4 shifts the relative populations of the multiple interconverting 20S proteasome conformations leading to an increase in substrate hydrolysis by an allosteric pathway. Based on our Tris-T4/h20S interaction model, Tris-T4 is able to affect gating dynamics and substrate hydrolysis by binding to an array of negatively charged and hydrophobic residues present on the protein surface involved in the 20S molecular activation by the regulatory proteins (RPs). Accordingly, despite the fact that Tris-T4 also binds to the α3ΔN mutant, allosteric modulation is not observed since the molecular mechanism connecting gate dynamics with substrate hydrolysis is impaired. We envisage that the dynamic view of the 20S conformational equilibria, activated through cooperative Tris-T4 binding, may work as a simplified model for a better understanding of the intricate network of 20S conformational/functional states that may be mobilized by exogenous ligands, paving the way for the development of a new generation of proteasome allosteric modulators

    The quassinoid derivative NBT-272 targets both the AKT and ERK signaling pathways in embryonal tumors

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    The quassinoid analogue NBT-272 has been reported to inhibit MYC, thus warranting a further effort to better understand its preclinical properties in models of embryonal tumors (ET), a family of childhood malignancies sharing relevant biological and genetic features such as deregulated expression of MYC oncogenes. In our study, NBT-272 displayed a strong anti-proliferative activity in vitro that resulted from the combination of diverse biological effects, ranging from G1/S arrest of the cell cycle to apoptosis and autophagy. The compound prevented the full activation of both the eukaryotic initiation factor 4E (eIF4E) and its binding protein 4EBP-1, regulating cap-dependent protein translation. Interestingly, all responses induced by NBT-272 in ET could be attributed to interference with two main pro-proliferative signaling pathways, i.e. the AKT and the MEK/extracellular signal-regulated kinase (ERK) pathways. These findings also suggested that the depleting effect of NBT-272 on MYC protein expression occurred via indirect mechanisms, rather than selective inhibition. Finally, the ability of NBT-272 to arrest tumor growth in a xenograft model of neuroblastoma plays a role in the strong anti-tumor activity of this compound, both in vitro and in vivo, with its potential to target cell-survival pathways that are relevant for the development and progression of ET

    COVID-19 related acro-ischemic neuropathic-like painful lesions in pediatric patients: A case seriese

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    Background: A variety of skin manifestations have been associated with COVID-19 infection. Acral lesions on hands and feet, closely resembling chilblains, have been reported in association with COVID-19, which are nonspecific. These acro-ischemic painful lesions have been described mainly in asymptomatic and mildly symptomatic pediatric COVID-19 positive patients, without a precise patho-genetic mechanism.COVID-19-induced chilblains may portend an indolent course and a good outcome. In young patients, the IFN-1 response induces microangiopathic changes and produces a chilblain lupus erythematosus-like eruption with vasculitic neuro-pathic pain features. Objectives: This paper presented a case series of pediatric patients with COVID-19-related skin lesions and neuropathic-like pain. Methods: Clinical outcomes were collected from 11 patients diagnosed with painful erythematous skin lesions with neuropathic-like pain and positive IgG for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Results: It is a mildly symptomatic condition not related to severe pain rates, and it is treated with paracetamol due to the transitory nature of the problem, which provides good results. Conclusions: A particular point of interest is skin lesion manifestation as a further indirect sign of SARS-CoV-2 infection. Due to the initial manifestation of chilblains in pauci-symptomatic pediatric patients, they need to be immediately tested and isolated. Chilblains can be considered a clinical clue to suspect SARS-CoV-2 infection and help in early diagnosis, patient triage, and infection control. © 2021, Author(s)
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