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关键词： Takotsubo cardiomyopathy   Acute coronary syndrome   Biomarkers   Differential diagnosis  

摘要： Introduction Takotsubo syndrome (TTS) is clinically indistinguishable from an acute coronary syndrome (ACS). In the absence of valid markers for differential diagnosis, coronary angiography has been indispensable. Methods In our study, we evaluated the serum levels of sST-2, GDF-15, suPAR and H-FABP in 92 patients with the suspicion of TTS (51 TTS and 41 ACS patients) and 40 gender matched controls (no coronary artery disease or signs of heart failure) at baseline. Results H-FABP was significantly higher in ACS patients compared to TTS patients. Even in in propensity score matching for left ventricular ejection fraction, sex and cardiovascular risk factors, differences in the plasma levels of H-FABP in the matched cohort of TTS vs ACS remained statistically significant. Whereas, sST-2 was significantly elevated in TTS patients. H-FABP was superior for prediction of an ACS with even higher accuracy than hs troponin in differential diagnosis (AUC 0.797, p ≤ 0.0001); the optimal cut off for discrimination towards a TTS was calculated as 2.93 ng/ml (sensitivity 70.0%, specificity 82.4%, PPV 75.7%, NPV 77.4%). sST-2 seemed most appropriate for identification of a TTS (AUC 0.653, p = 0.012). The optimal cut off for differential diagnosis was 11018.06 pg/ml (sensitivity 82.0%, specificity 51.2%, PPV 69.4%, NPV 71.9 %). Conclusion H-FABP and sST-2 are the most promising markers with better accuracy than preexisting biomarkers in differential diagnosis in our study and therefore, could be crucial for the guidance of treatment in patients with high bleeding risk, advanced renal failure or multimorbidity.

关键词： Lgr6   Maresin-1   Osteoprogenitor   R-spondin 2   Bone mass homeostasis  

摘要： Leucine-rich repeat containing G-protein-coupled receptor 6 (LGR6) is a marker of osteoprogenitor cells and is dynamically expressed during in vitro osteodifferentation of mouse and human mesenchymal stem cells (MSCs). While the Lgr6 genomic locus has been associated with osteoporosis in human cohorts, the precise molecular function of LGR6 in osteogenesis and maintenance of bone mass are not yet known. In this study, we performed in vitro Lgr6 knockdown and overexpression experiments in murine osteoblastic cells and find decreased Lgr6 levels results in reduced osteoblast proliferation, differentiation, and mineralization. Consistent with these data, overexpression of Lgr6 in these cells leads to significantly increased proliferation and osteodifferentiation. To determine whether these findings are recapitulated in vivo, we performed microCT and ex vivo osteodifferentiation analyses using our newly generated CRISPR-Cas9 mediated Lgr6 mouse knockout allele (Lgr6-K0). We find that ex vivo osteodifferentiation of Lgr6-KO primary MSCs is significantly reduced, and 8 week-old Lgr6-KO mice have less trabecular bone mass as compared to Lgr6 wildtype controls, indicating that Lgr6 is necessary for normal osteogenesis and bone mass. Towards mechanism, we analyzed in vitro signaling in the context of two LGR6 ligands, RSPO2 and MaR1 . We find that RSPO2 stimulates LGR6-mediated WNT/p-catenin signaling whereas MaR1 stimulates LGR6-mediated cAMP activity, suggesting two ligand-dependent functions for LGR6 receptor signaling during osteogenesis. Collectively, this study reveals that Lgr6 is necessary for wildtype levels of proliferation and differentiation of osteoblasts, and achieving normal bone mass.

摘要： There is a paucity of data concerning the usefulness of trichoscopy in patients with erythroderma. The aim of the study was to compare the trichoscopic features in erythroderma of various aetiologies. In total, 49 patients with a determined cause of erythroderma [including atopic dermatitis (AD), mycosis fungoides (MF), allergic contact eczema (ACE), psoriasis (Pso), Sezary syndrome (SS), drug reaction, pityriasis rubra pilaris (PRP), dermatomyositis (DM), actinic reticuloid (AR), crusted scabies (CS) and pemphigus foliaceus (PF)] were included in the study. Dotted vessels were present in patients with AD, PRP, MF, SS and Pso, and absent in DM, CS and PF (chi(2), P < 0.02). Spermatozoon-like vessels were observed only in MF and SS (P = 0.001). Whitish-pinkish structureless areas were described in all patients with DM, AR and CS (P < 0.03). The type of vessel and the presence of whitish-pinkish structureless areas under trichoscopy may indicate the cause of erythroderma.

关键词： Adomian decomposition method (ADM)   Modified Adomian decomposition method (MADM)   Two-step Adomian decomposition method (TSADM)   Caputo derivative   Non-linear initial value problem of fractional-order differential equations   Fixed point theorem  

摘要： The main focus of this study is to apply the two-step Adomian decomposition method (TSADM) for finding a solution of a fractional-order non-linear differential equation by using the Caputo derivative. We are interested in obtaining an analytical solution with two main constraints, that are, without converting the non-linear fractional differential equation to a system of linear algebraic fractional equation, and secondly, with less number of iterations. Moreover, we have investigated conditions for the existence and uniqueness of a solution with the help of some fixed point theorems. Furthermore, the method is demonstrated with the help of some examples. We also compare the results with the Adomian decomposition method (ADM), the modified Adomian decomposition method, and the combination of the ADM and a spectral method. It is concluded that the TSADM provides an analytical solution of fractional-order non-linear differential equation, while the other methods furnish an approximate solution.

关键词： Integro-differential problems   Anisotropic singular perturbations   Nonlinear hyperbolic problems   Schauder fixed point theorem   Asymptotic behaviour  

摘要： This paper is devoted to the study of existence of solutions to some integro-differential problems. We establish the existence of solutions by employing a singular perturbations method as a natural tool. The perturbed problems are classical, nonlocal, non-linear, hyperbolic and the limits of the subsequences of their solutions, in weighted Sobolev type spaces, are solutions of the main problem. The existence of a solution to the nonlocal hyperbolic problem can be ensured using the Schauder fixed point theorem. Published by Elsevier Masson SAS.

关键词： high entropy alloys   high-throughput experimentation   electrocatalysts   materials discovery  

摘要： High entropy alloys (HEA) comprise a huge search space for new electrocatalysts. Next to element combinations, the optimization of the chemical composition is essential for tuning HEA to specific catalytic processes. Simulations of electrocatalytic activity can guide experimental efforts. Yet, the currently available underlying model assumptions do not necessarily align with experimental evidence. To study deviations of theoretical models and experimental data requires statistically relevant datasets. Here, a combinatorial strategy for acquiring large experimental datasets of multi-dimensional composition spaces is presented. Ru-Rh-Pd-Ir-Pt is studied as an exemplary, highly relevant HEA system. Systematic comparison with computed electrochemical activity enables the study of deviations from theoretical model assumptions for compositionally complex solid solutions in the experiment. The results suggest that the experimentally obtained distribution of surface atoms deviates from the ideal distribution of atoms in the model. Leveraging both advanced simulation and large experimental data enables the estimation of electrocatalytic activity and solid-solution stability trends in the 5D composition space of the HEA system. A perspective on future directions for the development of active and stable HEA catalysts is outlined.

关键词： Copeptin   Vasopressin   Gastrointestinal microbiota   Hydration   Water   Obesity  

摘要： Introduction: Prevalence of chronic hypohydration remains elevated among adults in the USA;however, the health effects of hypohydration in regards to human gut health have not been explored. Methods: This study examined the relationship between total water intake, hydration biomarkers (first-morning urine specific gravity [FMUsg], first-morning urine volume [FMUvol], and plasma copeptin), fecal microbiota, and plasma lipopolysaccharide-binding protein (LBP) in adults (25-45 years, 64% female). Fecal microbiota composition was assessed using 16S rRNA gene sequencing (V4 region). Immunoassays quantified plasma copeptin and LBP in fasted venous blood samples. Dietary variables were measured using 7-day food records. Linear discriminant analysis effect size (LEfSe) analyzed differentially abundant microbiota based on median cutoffs for hydration markers. Multiple linear regressions examined the relationship between LBP and copeptin. Results: LEfSe identified 6 common taxa at the genus or species level that were differentially abundant in FMUsg, total water (g/day), or plasma copeptin (mu g/mL) groups when split by their median values. Uncultured species in the Bacteroides, Desulfovibrio, Roseburia, Peptococcus, and Akkermansia genera were more abundant in groups that might indicate poorer hydration status. Multivariate linear analyses revealed a positive relationship between plasma copeptin and LBP when controlling confounding variables (F(6,52) = 4.45, p = 0.002, R-2 = 0.34). Conclusions: Taxa common between markers are associated with the intestinal mucus layer, which suggests a potential link between hydration status and intestinal mucus homeostasis. The relationship between LBP and copeptin indicates that copeptin may be sensitive to metabolic endotoxemia and potentially gut barrier function.

关键词： Navier Stokes equations  

摘要： The dynamics of a subnormal mode of direct-current micro-discharge in pressurized nitrogen is studied using a self-consistent one-dimensional plasma fluid model coupled with the compressible Navier-Stokes equations. To clarify different time scales, we use a hierarchy of plasma reaction mechanisms. The simplest mechanism considers the two-species plasma without any excited species. The excitation of electronic and vibrational levels of nitrogen is only considered in the electron energy balance. The second mechanism considers multiple ions and electronically excited species. The most comprehensive third mechanism expands the second mechanism by tracking the vibrationally excited species as well as the reactions of vibrational-translational and vibrational-vibrational relaxation. By using this third mechanism, we analyze the dynamics associated with the relaxation of the vibrational distribution function of nitrogen.

关键词： malignant neoplasms   cancer of head and neck   minority groups   health disparity   survivors   socioeconomic factors  

摘要： IMPORTANCE Approximately 1 in 5 new patients with head and neck cancer (HNC) in the US belong to racial and ethnic minority groups, but their survival rates are worse than White individuals. However, because most studies compare Black vs White patients, little is known about survival differences among members of racial and ethnic minority groups. OBJECTIVE To describe differential survival and identify nonclinical factors associated with stage of presentation among patients with HNC belonging to racial and ethnic minority groups. DESIGN, SETTING. AND PARTICIPANTS This population-based retrospective cohort study used data from the 2007 to 2016 Surveillance, Epidemiology, and End Results (SEER) database and included non-Hispanic Black, Asian Pacific Islander, American Indian/Alaska Native, and Hispanic patients with HNC. The data were analyzed from December 2020 to May 2021. MAIN OUTCOMES AND MEASURES Outcomes were time to event measures: (HNC-specific and all-cause mortality) and stage of presentation. Covariates included nonclinical (age at diagnosis, sex, race and ethnicity, insurance status, marital status, and a composite socioeconomic status [SES]) and clinical factors (stage, cancer site, chemotherapy, radiation, and surgery). A Cox regression model was used to adjust associations of covariates with the hazard of all-cause death, and a Fine and Gray competing risks proportional hazards model was used to estimate associations of covariates with the hazard of HNC-specific death. A proportional log odds ordinal logistic regression identified which nonclinical factors were associated with stage of presentation. RESULTS There were 21 966 patients with HNC included in the study (mean [SD] age, 56.02 [11.16] years;6072 women [27.6%];9229 [42.0%] non-Hispanic Black, 6893 [31.4%] Hispanic, 5342 [24.3%] Asian/Pacific Islander, and 502 [2.3%] American Indian/Alaska Native individuals). Black patients had highest proportion with very low SES (3482 [37.7%]) and the lowest c

关键词： Mediterranean diet   metabolic syndrome   metabolic health   impaired glycemic control   metabolic risk factors   insulinemia   glycemic variability   continuous glucose monitoring   oral glucose tolerance test   meal glucose tolerance test  

摘要： A Mediterranean-style healthy eating pattern (MED-HEP) supports metabolic health, but the utility of including low-glycemic index (GI) foods to minimize postprandial glucose excursions remain unclear. Therefore, we investigated the relative contribution of GI towards improvements in postprandial glycemia and glycemic variability after adopting a MED-HEP. We conducted a randomized, controlled dietary intervention, comparing high- versus low-GI diets in a multi-national (Italy, Sweden, and the United States) sample of adults at risk for type 2 diabetes. For 12 weeks, participants consumed either a low-GI or high-GI MED-HEP. We assessed postprandial plasma glucose and insulin responses to high- or low-GI meals, and daily glycemic variability via continuous glucose monitoring at baseline and post-intervention. One hundred sixty adults (86 females, 74 males;aged 55 +/- 11 y, BMI 31 +/- 3 kg/m(2), mean +/- SD) with >= two metabolic syndrome traits completed the intervention. Postprandial insulin concentrations were greater after the high-GI versus the low-GI test meals at baseline (p = 0.004), but not post-intervention (p = 0.17). Postprandial glucose after the high-GI test meal increased post-intervention, being significantly higher than that after the low-GI test meal (35%, p < 0.001). Average daily glucose concentrations decreased in both groups post-intervention. Indices of 24-h glycemic variability were reduced in the low-GI group as compared to baseline and the high-GI intervention group. These findings suggest that low-GI foods may be an important feature within a MED-HEP.