50 research outputs found

    Influence of synthesis parameters on luminescence emission properties of some sol-gel derived Eu3+ doped willemite phosphors

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    Europium doped zinc silicate phosphor sample, corresponding to general formula, Zn2-(x+y)EuxLiySi0 4 , (where x = 0.01 or 0.02 and y = 0, 0.01, or 0, 02), have been synthesized by acid, or two steps (acid-base) catalyzed sol-gel processing, in the presence, or absence of Li+ ions, as charge compensator. The obtained xerogel samples was successively annealed, at different steps, up to 1000°C, for 180 minutes time soaking for each temperature. Starting from 700°C temperature, the formation of Si-O-Zn linkage was put in evidence by FT-IR spectra. The appearance of IR signals corresponding to willemite vibration modes has been observed for 900°C calcined samples. At UV excitation beam, the luminescence spectra of Zn2Si0 4 :Eu3+ synthesized phosphors samples show some emission peaks in the red region of spectra, assigned to 5Do—> Fj (j = 0, 1, 2, 3, 4 and 5) spin forbidden f-f transitions of Eu3+ ions, respectively. Specifically they were situated around 575 nm, 590 nm, 615 nm, 624 nm, 650 nm and 700 nm. The most intense emission was observed for the 1000°C calcined sample, with 0.02 moles Eu3+ activator content, prepared with charge compensator

    Cerebrospinal Fluid Alzheimer Markers in Depressed Elderly Subjects with and without Alzheimer's Disease

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    Depression and Alzheimer’s disease (AD) are among the most common clinical diagnosis in older people. The relation between depression and AD is complex: depression has been shown to be a risk factor, prodromal symptom and a consequence of AD. Increased understanding of the underlying mechanisms of depression in AD may lead to early detection and differential diagnosis, and is crucial for development of novel and mechanism-based treatments. The first two studies of this doctoral thesis are exploring the associations between depressive symptoms and biomarkers of amyloid deposition and neuronal injury in patients with subjective cognitive impairment (SCI), mild cognitive impairment (MCI) and AD. The aims of the third study were to describe the use of antidepressants in patients with dementia and to explore the association between mortality risk and the use of antidepressants 3 years before the dementia diagnosis. CAIDE Dementia Risk Score is taking into account midlife risk and protective factors; age, educational level, gender, systolic blood pressure, body mass index, cholesterol level and physical activity and APOE genotyping, and can predict dementia over 20 years. The last study was focused on exploring the associations between CAIDE Dementia Risk Score and biomarkers of amyloid deposition, neuronal injury and small vessel pathology in SCI and MCI patients. Additionally we explored the capacity of CAIDE Dementia Risk Score to predict dementia in a memory clinic population. Data were obtained from Memory Clinic Karolinska University Hospital Huddinge Sweden (Study I, II and IV). In study III, two large national registries were merged: the Swedish Dementia Registry (SveDem) and the Swedish Prescribed Drug Register. In study I, analysis of the three different cerebrospinal fluid biomarkers; amyloid beta (CSF Aβ), total-tau (CSF t-tau), and phosphorylated-tau did not support the hypothesis that more severe amyloid or tau pathologies are associated with more severe depressive symptoms. In contrast, SCI and AD patients with depressive symptoms tended to have lower CSF p-tau levels and, in particular, lower CSF t-tau levels than those without depression, indicating less severe neuronal injury. In study II, we used two different analysis methods of MRI to measure medial temporal lobe atrophy and hippocampus volume. Using manual tracing of the hippocampi we found smaller left hippocampus volume in SCI patients with depressive symptoms compared to those without depressive symptoms. In contrast, AD patients with depressive symptoms had less medial temporal lobe atrophy compared with those without depressive symptoms. In study III, 20,050 patients with incident dementia diagnosed in memory clinics and registered in SveDem were included. Information on the total number of medication and all antidepressants dispensed at the time of dementia diagnosis and at the first, the second and the third year prior to dementia diagnosis was obtained from the Swedish Prescribed Drug Register. During a median follow up of 2 years, 5168 (25.8%) dementia patients died. At the time of dementia diagnosis, 5,004 (25.0%) patients were on antidepressant treatment. Use of antidepressant treatment for 3 consecutive years prior to a dementia diagnosis was associated with a lower mortality risk for all dementia disorders in general and particularly in AD. In study IV, a higher CAIDE Dementia Risk Score was associated with higher CSF t-tau levels, more severe medial temporal lobe atrophy and more severe white matter changes. For the CAIDE score including APOE, a score above 9 points was associated with lower CSF Aβ, more severe medial temporal lobe atrophy and more severe white matter changes. CAIDE Dementia Risk Score (version with APOE) performed better at predicting AD compared with CAIDE Dementia Risk Score without APOE. Conclusion: We found that depressive symptoms in patients with AD and SCI are not associated with more amyloid deposition nor more neuronal injury compared with AD and SCI patients without depressive symptoms. Thus our results are consistent with the hypothesis that the mechanisms underlying depression differ between older people with and without AD. Our results have shown that use of antidepressants in prodromal AD stages is associated with a lower mortality risk. Further longitudinal studies are needed to better understand the associations between the use of antidepressants and mortality risk in dementia

    Intestinal dysbiosis – a new treatment target in the prevention of colorectal cancer

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    The gastrointestinal microbiome contains at least 100 trillion microorganisms (bacteria, viruses, fungi), whose distribution varies from the mouth to the rectum spatially and temporally throughout one\u27s lifetime. The microbiome benefits from advancing research due to its major role in human health. Studies indicate that its functions are immunity, metabolic processes and mucosal barrier. The disturbances of these functions, dysbiosis, influence physiology, lead to diabetes, inflammatory bowel disease, obesity and colon tumorigenesis. The third most common form of cancer, colorectal cancer, is the result of many factors and genes, and although the link between dysbiosis and this type of cancer is poorly characterized, it has been shown that some bacterial species and their metabolites have a critical role in developing colorectal cancer. Also, gut microbiota plays a role in the inflammatory response and immune process perturbations during the progression of colorectal cancer. Some new technologies, such as metagenome sequencing, facilitated the progress by analyzing the metabolic and genetic profile of microbiota, revealing details about the bacterial composition, host interactions, and taxonomic alterations. This review summarizes the studies regarding the link between gut microbiota and colorectal cancer, targeting new therapeutic strategies

    Whole-blood expression of inflammasome- and glucocorticoid-related mRNAs correctly separates treatment-resistant depressed patients from drug-free and responsive patients in the BIODEP study

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    Funder: DH | National Institute for Health Research (NIHR); doi: https://doi.org/10.13039/501100000272Abstract: The mRNA expression signatures associated with the ‘pro-inflammatory’ phenotype of depression, and the differential signatures associated with depression subtypes and the effects of antidepressants, are still unknown. We examined 130 depressed patients (58 treatment-resistant, 36 antidepressant-responsive and 36 currently untreated) and 40 healthy controls from the BIODEP study, and used whole-blood mRNA qPCR to measure the expression of 16 candidate mRNAs, some never measured before: interleukin (IL)-1-beta, IL-6, TNF-alpha, macrophage inhibiting factor (MIF), glucocorticoid receptor (GR), SGK1, FKBP5, the purinergic receptor P2RX7, CCL2, CXCL12, c-reactive protein (CRP), alpha-2-macroglobulin (A2M), acquaporin-4 (AQP4), ISG15, STAT1 and USP-18. All genes but AQP4, ISG15 and USP-18 were differentially regulated. Treatment-resistant and drug-free depressed patients had both increased inflammasome activation (higher P2RX7 and proinflammatory cytokines/chemokines mRNAs expression) and glucocorticoid resistance (lower GR and higher FKBP5 mRNAs expression), while responsive patients had an intermediate phenotype with, additionally, lower CXCL12. Most interestingly, using binomial logistics models we found that a signature of six mRNAs (P2RX7, IL-1-beta, IL-6, TNF-alpha, CXCL12 and GR) distinguished treatment-resistant from responsive patients, even after adjusting for other variables that were different between groups, such as a trait- and state-anxiety, history of childhood maltreatment and serum CRP. Future studies should replicate these findings in larger, longitudinal cohorts, and test whether this mRNA signature can identify patients that are more likely to respond to adjuvant strategies for treatment-resistant depression, including combinations with anti-inflammatory medications

    The Internal Audit in Private Companies

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    One of the major characteristics of the audit is to permanently resort to various criteria, norms and standards. This attitude is, on the other hand, much more systematic as the audit is applied as professional norms. It is of a major importance to respect the stages of the financial-accounting audit, both for the auditors and for the patrimonial audited unit whose administration can be defined as a totality of decisions that apply its strategy. We may consider that when the financial audit gets support from the internal control it appears as an operational audit, and when it determines the application of the strategy it appears as the audit of the administration control.linternal audit, private companies, strategy, control;
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