16 research outputs found

    Multiple blood-brain barrier transport mechanisms limit bumetanide accumulation, and therapeutic potential, in the mammalian brain

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    There is accumulating evidence that bumetanide, which has been used over decades as a potent loop diuretic, also exerts effects on brain disorders, including autism, neonatal seizures, and epilepsy, which are not related to its effects on the kidney but rather mediated by inhibition of the neuronal Na-K-C1 cotransporter isoform NKCC1. However, following systemic administration, brain levels of bumetanide are typically below those needed to inhibit NKCC1, which critically limits its clinical use for treating brain disorders. Recently, active efflux transport at the blood-brain barrier (BBB) has been suggested as a process involved in the low brain:plasma ratio of bumetanide, but it is presently not clear which transporters are involved. Understanding the processes explaining the poor brain penetration of bumetanide is needed for developing strategies to improve the brain delivery of this drug. In the present study, we administered probenecid and more selective inhibitors of active transport carriers at the BBB directly into the brain of mice to minimize the contribution of peripheral effects on the brain penetration of bumetanide. Furthermore, in vitro experiments with mouse organic anion transporter 3 (Oat3)-overexpressing Chinese hamster ovary cells were performed to study the interaction of bumetanide, bumetanide derivatives, and several known inhibitors of Oats on Oat3-mediated transport. The in vivo experiments demonstrated that the uptake and efflux of bumetanide at the BBB is much more complex than previously thought. It seems that both restricted passive diffusion and active efflux transport, mediated by Oat3 but also organic anion-transporting polypeptide (Oatp) Oatpla4 and multidrug resistance protein 4 explain the extremely low brain concentrations that are achieved after systemic administration of bumetanide, limiting the use of this drug for targeting abnormal expression of neuronal NKCC1 in brain diseases

    Evaluation of polygenic risk scores for breast and ovarian cancer risk prediction in BRCA1 and BRCA2 mutation carriers

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    Background: Genome-wide association studies (GWAS) have identified 94 common single-nucleotide polymorphisms (SNPs) associated with breast cancer (BC) risk and 18 associated with ovarian cancer (OC) risk. Several of these are also associated with risk of BC or OC for women who carry a pathogenic mutation in the high-risk BC and OC genes BRCA1 or BRCA2. The combined effects of these variants on BC or OC risk for BRCA1 and BRCA2 mutation carriers have not yet been assessed while their clinical management could benefit from improved personalized risk estimates. Methods: We constructed polygenic risk scores (PRS) using BC and OC susceptibility SNPs identified through population-based GWAS: for BC (overall, estrogen receptor [ER]-positive, and ER-negative) and for OC. Using data from 15 252 female BRCA1 and 8211 BRCA2 carriers, the association of each PRS with BC or OC risk was evaluated using a weighted cohort approach, with time to diagnosis as the outcome and estimation of the hazard ratios (HRs) per standard deviation increase in the PRS. Results: The PRS for ER-negative BC displayed the strongest association with BC risk in BRCA1 carriers (HR = 1.27, 95% confidence interval [CI] = 1.23 to 1.31, P = 8.2 x 10(53)). In BRCA2 carriers, the strongest association with BC risk was seen for the overall BC PRS (HR = 1.22, 95% CI = 1.17 to 1.28, P = 7.2 x 10(-20)). The OC PRS was strongly associated with OC risk for both BRCA1 and BRCA2 carriers. These translate to differences in absolute risks (more than 10% in each case) between the top and bottom deciles of the PRS distribution; for example, the OC risk was 6% by age 80 years for BRCA2 carriers at the 10th percentile of the OC PRS compared with 19% risk for those at the 90th percentile of PRS. Conclusions: BC and OC PRS are predictive of cancer risk in BRCA1 and BRCA2 carriers. Incorporation of the PRS into risk prediction models has promise to better inform decisions on cancer risk management

    Mutational spectrum in a worldwide study of 29,700 families with BRCA1 or BRCA2 mutations.

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    The prevalence and spectrum of germline mutations in BRCA1 and BRCA2 have been reported in single populations, with the majority of reports focused on White in Europe and North America. The Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) has assembled data on 18,435 families with BRCA1 mutations and 11,351 families with BRCA2 mutations ascertained from 69 centers in 49 countries on six continents. This study comprehensively describes the characteristics of the 1,650 unique BRCA1 and 1,731 unique BRCA2 deleterious (disease-associated) mutations identified in the CIMBA database. We observed substantial variation in mutation type and frequency by geographical region and race/ethnicity. In addition to known founder mutations, mutations of relatively high frequency were identified in specific racial/ethnic or geographic groups that may reflect founder mutations and which could be used in targeted (panel) first pass genotyping for specific populations. Knowledge of the population-specific mutational spectrum in BRCA1 and BRCA2 could inform efficient strategies for genetic testing and may justify a more broad-based oncogenetic testing in some populations

    Sensing properties, energy transfer mechanism and tuneable particle size processing of luminescent two-dimensional rare earth coordination networks

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    A new isostructural family of layered coordination networks (CNs) based on rare earth elements and mixed ligands was hydrothermally synthesized and fully characterized. The set of compounds with the general formula [REE(Salicylate)(Succinate)0.5(H2O)] (with REE = Ho or Y) belong to the monoclinic P21/c space group. Top-down methods were implemented in order to obtain nano-sized CN particles for potential application in thin film fabrication. The solid state photoluminescence (SSPL) of the Eu, Tb and Eu/Tb doped samples was explored in terms of excitation/emission spectra, lifetime values and quantification of light emission by the CIE chromaticity calculation. Measurement of the triplet state energy of the ligand at low temperature was carried out by analysing the SSPL of the Y-based compound; energy transfer pathways were studied. According to the high performance of the Tb-doped compound as a green emitter, thermal and chemical sensing assays were carried out.Fil: Godoy, Agustín Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Gomez, Germán Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Kaczmarek, Anna M.. University of Ghent; BélgicaFil: Van Deun, Rik. University of Ghent; BélgicaFil: Furlong, Octavio Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; ArgentinaFil: Gándara, Felipe. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Monge, María A.. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Bernini, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Narda, Griselda Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin

    Layered exfoliable crystalline materials based on Sm-, Eu- and Eu/Gd-2-phenylsuccinate frameworks. Crystal structure, topology and luminescence properties

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    Three new layered metal–organic frameworks (MOFs) based on 2-phenylsuccinic acid (H2psa) and lanthanide ions with the formula [Ln2(C10H8O4)3(H2O)] (Ln = Eu, Sm and Eu–Gd) have been synthesized under solvothermal conditions and fully characterized by single-crystal X-ray diffraction, thermal and vibrational analyses. The compounds are isostructural featuring 2D frameworks that consist of infinite zigzag chains composed of [LnO8] and [LnO8(H2O)] edge-sharing polyhedra linked by psa ligands leading to layers further connected by weak π–π interactions in an edge orientation. Moreover, a topological study was carried out to obtain the simplified net for better comparison with structurally related compounds. The Eu-psa crystals were exfoliated into nanolayers after miniaturization by addition of sodium acetate as a capping agent in the reaction medium. Scanning electron microscopy was applied to characterize the miniaturized samples whereas the exfoliated hybrid nanosheets were studied by atomic force microscopy. The photoluminescence (PL) properties of the bulk compounds as well as the miniaturized and exfoliated materials were investigated and compared with other related ones. An exhaustive study of the Eu(III)-based MOFs was performed on the basis of the obtained PL parameters (excitation and emission spectra, kr, knr, intrinsic quantum yields and lifetimes) to explore the underlying structure–property relationships.Fil: Gomez, Germán Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Investigaciones En Tecnología Química; ArgentinaFil: Bernini, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Brusau, Elena Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Investigaciones En Tecnología Química; ArgentinaFil: Narda, Griselda Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Vega, Daniel Roberto. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes. Gerencia de Investigación y Aplicaciones; ArgentinaFil: Kaczmarek, A. M.. University Of Ghent; BélgicaFil: Van Deun, R.. University Of Ghent; BélgicaFil: Nazzarro, Marcelo Sandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Física Aplicada; Argentin

    The Fami-life study: protocol of a prospective observational multicenter mixed study of psychological consequences of grieving relatives in French palliative care units on behalf of the family research in palliative care (F.R.I.P.C research network)

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    International audienceBACKGROUND:Grieving relatives can suffer from numerous consequences like anxiety, depression, post-traumatic stress disorder (PTSD) symptoms, and prolonged grief. This study aims to assess the psychological consequences of grieving relatives after patients' death in French palliative care units and their needs for support.METHODS:This is a prospective observational multicenter mixed study. Relatives of adult patients with a neoplasia expected to be hospitalized more than 72 h in a palliative care unit for end-of-life issues will be included within 48 h after patient admission. End-of-life issues are defined by the physician at patient admission. Relatives who are not able to have a phone call at 6-months are excluded. The primary outcome is the incidence of prolonged grief reaction defined by an ICG (Inventory Complicate Grief) > 25 (0 best-76 worst) at 6 months after patient' death. Prespecified secondary outcomes are the risk factors of prolonged grief, anxiety and depression symptoms between day 3 and day 5 and at 6 months after patients' death based on an Hospital Anxiety and Depression score (range 0-42) > 8 for each subscale (minimal clinically important difference: 2.5), post-traumatic stress disorder symptoms 6 months after patient' death based on the Impact of Events Scale questionnaire (0 best-88 worst) score > 22, experience of relatives during palliative care based on the Fami-Life questionnaire, specifically built for the study. Between 6 and 12 months after the patient's death, a phone interview with relatives with prolonged grief reactions will be planned by a psychologist to understand the complex system of grief. It will be analyzed with the Interpretative Phenomenological Analysis. We planned to enroll 500 patients and their close relatives assuming a 25% prolonged grief rate and a 6-month follow-up available in 60% of relatives.DISCUSSION:This study will be the first to report the psychological consequences of French relatives after a loss of a loved one in palliative care units. Evaluating relatives' experiences can provide instrumental insights for means of improving support for relatives and evaluation of bereavement programs
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