209 research outputs found

    Density functional electronic spectrum of the CuO610Cu O_{-6}^{-10} cluster and possible local Jahn-Teller distorsions in the La-Ba-Cu-O superconductor

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    We present a density functional theory (DFT) calculation in the generalized gradient approximation to study the possibility for the existence of Jahn-Teller (JT) or pseudo Jahn-Teller (PJT) type local distortions in the La-Ba-Cu-O superconducting system. We performed the calculation and correspondingly group theory classification of the electronic ground state of the CuO610{_{6}}^{-10} elongated octahedra cluster, immersed in a background simulating the superconductor. Part of the motivation to do this study is that the origin of the apical deformation of the CuO610{_{6}}^{-10} cluster is not due to a pure JT effect, having therefore a non {\it a priori} condition to remove the degeneracy of the electronic ground state of the parent regular octahedron. We present a comparative analysis of the symmetry classified electron spectrum with previously reported results using unrestricted Hartree-Fock calculations (UHF). Both the DFT and UHF calculations produced a non degenerate electronic ground state, not having therefore the necessary condition for a pure JT effect. However, the appearance of a degenerate Eg_{g} state near to the highest occupied molecular orbital in the DFT calculation, suggests the possibility for a PJT effect responsible for a local distortion of the oxidized CuO69_{6}^{-9} cluster.Comment: 12 pages, 3 figures, submitted to International Journal of Modern Physics B (IJMPB

    Increased Glycemic Variability Is Independently Associated With Length of Stay and Mortality in Noncritically Ill Hospitalized Patients

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    OBJECTIVE To investigate the association between glycemic variability (GV) and both length of stay (LOS) and 90-day mortality in noncritically ill hospitalized patients. RESEARCH DESIGN AND METHODS This study retrospectively analyzed 4,262 admissions to the general medicine or surgery services during a 2 year period. Patients with point-of-care glucose monitoring and a minimum of two glucose values per day on average were selected. GV was assessed by SD and coefficient of variation (CV). Data were analyzed with linear and logistic multivariate regression analysis in separate models for SD and CV. Analysis was performed with generalized estimating equations to adjust for correlation between multiple admissions in some individual cases. RESULTS After exclusions, 935 admissions comprised the sample. Results of adjusted analysis indicate that for every 10 mg/dL increase in SD and 10–percentage point increase in CV, LOS increased by 4.4 and 9.7%, respectively. Relative risk of death in 90 days also increased by 8% for every 10-mg/dL increase in SD. These associations were independent of age, race, service of care (medicine or surgery), previous diagnosis of diabetes, HbA1c, BMI, the use of regular insulin as a sole regimen, mean glucose, and hypoglycemia occurrence during the hospitalization. CONCLUSIONS Our results indicate that increased GV during hospitalization is independently associated with longer LOS and increased mortality in noncritically ill patients. Prospective studies with continuous glucose monitoring are necessary to investigate this association thoroughly and to generate therapeutic strategies targeted at decreasing GV. Inpatient hyperglycemia is common, and it has been associated with increased morbidity and mortality in patients with and without diabetes (1–7). In the intensive care unit (ICU) setting, hypoglycemia has also been independently associated with a significant increase in mortality (8–10). Recently, a third metric of glucose control, known as glycemic variability (GV), has been proposed to be additionally implicated in the disease-associated process of dysglycemia (11). GV refers to fluctuations of blood glucose values around the mean and has been posited as a novel marker for poor glycemic control (12,13). In vitro and human studies suggest that high GV leads to greater oxidative stress than does sustained hyperglycemia (14,15). Studies of ICU patients have consistently demonstrated that increased GV is independently associated with higher mortality (16–19). Notably, results from a large multicenter study concluded that GV was a stronger predictor of ICU mortality than was mean glucose concentrations (20). Although there is no consensus as to the best method to determine GV in hospitalized patients, the use of SD of glucose values has been well validated by previous ICU studies (16,20). Coefficient of variation (CV) has also been suggested as a strong independent index for measuring GV because it corrects for mean glucose levels (21,22). Despite substantial scientific evidence from the ICU, no previous studies have investigated the association between GV and clinical outcomes in patients admitted to the general medical and surgical wards. The purpose of this study was therefore to investigate the association between GV and length of stay (LOS) and 90-day mortality in noncritically ill hospitalized patients. We hypothesize that increased GV in this setting is associated with increased LOS and mortality

    Biases in study design, implementation, and data analysis that distort the appraisal of clinical benefit and ESMO-Magnitude of Clinical Benefit Scale (ESMO-MCBS) scoring

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    BACKGROUND: The European Society for Medical Oncology-Magnitude of Clinical Benefit Scale (ESMO-MCBS) is a validated, widely used tool developed to score the clinical benefit from cancer medicines reported in clinical trials. ESMO-MCBS scores assume valid research methodologies and quality trial implementation. Studies incorporating flawed design, implementation, or data analysis may generate outcomes that exaggerate true benefit and are not generalisable. Failure to either indicate or penalise studies with bias undermines the intention and diminishes the integrity of ESMO-MCBS scores. This review aimed to evaluate the adequacy of the ESMO-MCBS to address bias generated by flawed design, implementation, or data analysis and identify shortcomings in need of amendment. METHODS: As part of a refinement of the ESMO-MCBS, we reviewed trial design, implementation, and data analysis issues that could bias the results. For each issue of concern, we reviewed the ESMO-MCBS v1.1 approach against standards derived from Helsinki guidelines for ethical human research and guidelines from the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use, the Food and Drugs Administration, the European Medicines Agency, and European Network for Health Technology Assessment. RESULTS: Six design, two implementation, and two data analysis and interpretation issues were evaluated and in three, the ESMO-MCBS provided adequate protections. Seven shortcomings in the ability of the ESMO-MCBS to identify and address bias were identified. These related to (i) evaluation of the control arm, (ii) crossover issues, (iii) criteria for non-inferiority, (iv) substandard post-progression treatment, (v) post hoc subgroup findings based on biomarkers, (vi) informative censoring, and (vii) publication bias against quality-of-life data. CONCLUSION: Interpretation of the ESMO-MCBS scores requires critical appraisal of trials to understand caveats in trial design, implementation, and data analysis that may have biased results and conclusions. These will be addressed in future iterations of the ESMO-MCBS.SCOPUS: re.jinfo:eu-repo/semantics/publishe

    Recommendations for vaccination in patients with multiple sclerosis who are eligible for immunosuppressive therapies: Spanish consensus statement

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    Background: The recent development of highly effective treatments for multiple sclerosis (MS) and the potential risk of infectious complications require the development of prevention and risk minimisation strategies. Vaccination is an essential element of the management of these patients. This consensus statement includes a series of recommendations and practical scenarios for the vaccination of adult patients with MS who are eligible for highly effective immunosuppressive treatments. Methodology: A formal consensus procedure was followed. Having defined the scope of the statement, we conducted a literature search on recommendations for the vaccination of patients with MS and specific vaccination guidelines for immunosuppressed patients receiving biological therapy for other conditions. The modified nominal group technique methodology was used to formulate the recommendations. Development: Vaccination in patients who are candidates for immunosuppressive therapy should be considered before starting immunosuppressive treatment providing the patient's clinical situation allows. Vaccines included in the routine adult vaccination schedule, as well as some specific ones, are recommended depending on the pre-existing immunity status. If immunosuppressive treatment is already established, live attenuated vaccines are contraindicated. For vaccines with a correlate of protection, it is recommended to monitor the serological response in an optimal interval of 1-2 months from the last dose.Antecedentes: La reciente aparición de terapias de alta efectividad para el tratamiento de la esclerosis múltiple (EM), con potencial riesgo de complicaciones infecciosas, obliga plantear estrategias de prevención y minimización de riesgos. La vacunación constituye una parte esencial del manejo de estos pacientes. Este consenso recoge una serie de pautasy escenarios prácticos de vacunación en pacientes adultos con EM candidatos a tratamiento inmunosupresor. Metodología: Se llevó a cabo un consenso de tipo formal. Tras definir el alcance del documento, se realizó una búsqueda bibliográfica de vacunación en pacientes con EM, así como guías de vacunación específicas de pacientes inmunosuprimidosy en tratamiento biológico con otras enfermedades.Para la formulación de las recomendaciones se empleó la metodología de Modified Nominal Group Technique. Desarrollo: La vacunación en pacientes candidatos a tratamiento inmunosupresor se debe plantear antes de iniciar un tratamiento inmunosupresor siempre que la situación clínica del paciente lo permita. Se recomendarán tanto aquellas indicadas en el calendario vacunal del adulto, como algunas específicas, en función de la inmunidad previa. Si ya está instaurado el tratamiento inmunosupresor las vacunas vivas atenuadas estarán contraindicadas.Para aquellas vacunas que dispongan de un correlato de protección se recomienda monitorizar la respuesta serológica transcurridos de uno a2 meses de la última dosi

    An International Comparison of Presentation, Outcomes and CORONET Predictive Score Performance in Patients with Cancer Presenting with COVID-19 across Different Pandemic Waves.

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    Patients with cancer have been shown to have increased risk of COVID-19 severity. We previously built and validated the COVID-19 Risk in Oncology Evaluation Tool (CORONET) to predict the likely severity of COVID-19 in patients with active cancer who present to hospital. We assessed the differences in presentation and outcomes of patients with cancer and COVID-19, depending on the wave of the pandemic. We examined differences in features at presentation and outcomes in patients worldwide, depending on the waves of the pandemic: wave 1 D614G (n = 1430), wave 2 Alpha (n = 475), and wave 4 Omicron variant (n = 63, UK and Spain only). The performance of CORONET was evaluated on 258, 48, and 54 patients for each wave, respectively. We found that mortality rates were reduced in subsequent waves. The majority of patients were vaccinated in wave 4, and 94% were treated with steroids if they required oxygen. The stages of cancer and the median ages of patients significantly differed, but features associated with worse COVID-19 outcomes remained predictive and did not differ between waves. The CORONET tool performed well in all waves, with scores in an area under the curve (AUC) of >0.72. We concluded that patients with cancer who present to hospital with COVID-19 have similar features of severity, which remain discriminatory despite differences in variants and vaccination status. Survival improved following the first wave of the pandemic, which may be associated with vaccination and the increased steroid use in those patients requiring oxygen. The CORONET model demonstrated good performance, independent of the SARS-CoV-2 variants

    Mapping adipose and muscle tissue expression quantitative trait loci in African Americans to identify genes for type 2 diabetes and obesity

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    Relative to European Americans, type 2 diabetes (T2D) is more prevalent in African Americans (AAs). Genetic variation may modulate transcript abundance in insulin-responsive tissues and contribute to risk; yet published studies identifying expression quantitative trait loci (eQTLs) in African ancestry populations are restricted to blood cells. This study aims to develop a map of genetically regulated transcripts expressed in tissues important for glucose homeostasis in AAs, critical for identifying the genetic etiology of T2D and related traits. Quantitative measures of adipose and muscle gene expression, and genotypic data were integrated in 260 non-diabetic AAs to identify expression regulatory variants. Their roles in genetic susceptibility to T2D, and related metabolic phenotypes were evaluated by mining GWAS datasets. eQTL analysis identified 1,971 and 2,078 cis-eGenes in adipose and muscle, respectively. Cis-eQTLs for 885 transcripts including top cis-eGenes CHURC1, USMG5, and ERAP2, were identified in both tissues. 62.1% of top cis-eSNPs were within ±50kb of transcription start sites and cis-eGenes were enriched for mitochondrial transcripts. Mining GWAS databases revealed association of cis-eSNPs for more than 50 genes with T2D (e.g. PIK3C2A, RBMS1, UFSP1), gluco-metabolic phenotypes, (e.g. INPP5E, SNX17, ERAP2, FN3KRP), and obesity (e.g. POMC, CPEB4). Integration of GWAS meta-analysis data from AA cohorts revealed the most significant association for cis-eSNPs of ATP5SL and MCCC1 genes, with T2D and BMI, respectively. This study developed the first comprehensive map of adipose and muscle tissue eQTLs in AAs (publically accessible at https://mdsetaa.phs.wakehealth.edu) and identified genetically-regulated transcripts for delineating genetic causes of T2D, and related metabolic phenotypes
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