19 research outputs found

    Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization

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    We show that dynamic nuclear polarization (DNP) can be used to enhance NMR signals of13C and 29Si nuclei located in mesoporous organic/inorganic hybrid materials, at several hundreds of nanometers from stable radicals (TOTAPOL) trapped in the surrounding frozen disordered water. The approach is demonstrated using mesoporous silica nanoparticles (MSN), functionalized with 3-(N-phenylureido)propyl (PUP) groups, filled with the surfactant cetyltrimethylammonium bromide (CTAB). The DNP-enhanced proton magnetization is transported into the mesopores via 1H–1H spin diffusion and transferred to rare spins by cross-polarization, yielding signal enhancements εon/off of around 8. When the CTAB molecules are extracted, so that the radicals can enter the mesopores, the enhancements increase to εon/off ≈ 30 for both nuclei. A quantitative analysis of the signal enhancements in MSN with and without surfactant is based on a one-dimensional proton spin diffusion model. The effect of solvent deuteration is also investigated

    Kinase-templated abiotic reaction

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    Protein kinases are quintessential regulators of cellular function. Numerous pathologies are intimately linked to the dysregulated activity of a particular protein kinase. Herein we report a technology based on a proximity-induced chemical transformation that enables the detection and imaging of specific kinases. Using two probes that target the nucleotide-binding site and substrate binding site of a target kinase respectively, the reagents appended on the probes are brought within reactive distance thereby enabling the chemical transformation. The reaction used for sensing is a ruthenium-photocatalyzed reduction of a pyridinium immolative linker, which uncages a fluorophore (rhodamine). We demonstrate that this technology can be used to discriminate between closely related kinases with a high signal to noise ratio. We further demonstrate that the technology operates within the complexity of a cellular context with a good correlation between the level of kinase activity and fluorescence output

    Psychiatric emergency admissions during and after COVID-19 lockdown: short-term impact and long-term implications on mental health

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    Background: The \u2018lockdown\u2019 measures, adopted to restrict population movements in order to help curb the novel coronavirus disease 2019 (COVID-19) pandemic, contributed to a global mental health crisis. Although several studies have extensively examined the impact of lockdown measures on the psychological well-being of the general population, little is known about long-term implications. This study aimed to identify changes in psychiatric emergency department (ED) admissions between two 8-week periods: during and immediately after lifting the lockdown. Methods: Socio-demographic and clinical information on 1477 psychiatric ED consultations at the University Hospital of Geneva (HUG) were retrospectively analyzed. Results: When grouped according to admission dates, contrary to what we expected, the post-lockdown group presented with more severe clinical conditions (as measured using an urgency degree index) compared to their lockdown counterparts. Notably, after the lockdown had been lifted we observed a statistically significant increase in suicidal behavior and psychomotor agitation and a decrease in behavior disorder diagnoses. Furthermore, more migrants arrived at the HUG ED after the lockdown measures had been lifted. Logistic regression analysis identified diagnoses of suicidal behavior, behavioral disorders, psychomotor agitation, migrant status, involuntary admission, and private resident discharge as predictors of post-lockdown admissions. Conclusions: Collectively, these findings can have implications concerning the prioritization of mental health care facilities and access for patients at risk of psychopathological decompensation in time of confinement policies, but above all, provide a foundation for future studies focusing on the long-term impact of the pandemic and its associated sanitary measures on mental health. Trial registration: Research Ethics Committee of Geneva, Registration number 2020\u201301510, approval date: 29 June 2020

    Impact of the COVID\u201019 pandemic on psychiatric admissions to a large swiss emergency department: An observational study

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    The coronavirus disease 2019 (COVID\u201019) pandemic is a public health emergency with profound mental health consequences. The psychiatric emergency department (ED) plays a key role during this mental health crisis. This study aimed to investigate differences in admissions at a Swiss psychiatric ED from 1 April to 15 May during a \u201cpandemic\u2010free\u201d period in 2016 and a \u201cduringpandemic\u201d period in 2020. The study included 579 consultations at psychiatric ED in the \u201cduringpandemic\u201d period and 702 in the \u201cpandemic\u2010free\u201d period. Sociodemographic and clinical characteristics were compared, and logistic regression analysis was performed to identify variables associated with psychiatric admissions during the pandemic. A reduction in total psychiatric ED admissions was documented during COVID\u201019. Logistic regression analysis predicted the independent variable (ED admission during the pandemic) and estimated odds ratio (OR) for being unmarried/not in a relationship, arrival in an ambulance, suicidal behavior, behavioral disorders and psychomotor agitation. Though only statistically significant in bivariate analysis, patients were also more likely to be involuntarily hospitalized. This picture appears to be reversed from a sociodemographic and clinical point of view to our observation of psychiatric ED consultation in 2016. These findings highlight that the reduction in psychiatric ED admissions during the pandemic seems to be associated with living alone and more severe psychopathologies, which must alert psychiatrists to ensure access to mental health care in times of pandemic
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