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The synthesis and crystallographic site occupancy were investigated for MgAl2O4 with and without mechanical activation of the precursor powders. Heating to 1200 °C or higher resulted in the formation of a single spinel phase regardless of whether the powders were mechanically activated or not. Neutron diffraction analysis was used to determine cation site occupancy and revealed that mechanical activation resulted in a lower degree of cation site inversion compared to the nonactivated materials, which indicated that the powders were closer to thermodynamic equilibrium. This is the first study to characterize the effects of mechanical activation on crystallographic site occupancy in magnesium aluminate spinel using neutron diffraction.  相似文献   
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The current study aimed to assess the topographical and physical properties of a minimally invasive implant (MagiCore®: MC®, InnosBioSurg, IBS) and to evaluate its biological behavior compared to a gold standard implant (NobelParallel™: NB™, Nobel Biocare™). After surface characterization, the biological behavior assessment was conducted regarding human gingival fibroblasts (hGF) and osteoblast-like cells (MG63). Roughness values for NBTM were Ra = 1.28 µm and for MC® they were Ra = 2.02 µm. Alamar BlueTM assay LIVE/DEADTM staining results indicated equivalent biological development regarding both cell types for the two implants. Significant enhancement was found for hGF ALP activity in the presence of the two tested implants in a time-dependent manner from day 7 to day 14 (** p < 0.01). Alizarin red staining demonstrated significant calcium deposition enhancement when cells were interfaced with the NB™ compared to the MC® implant (** p < 0.05). Moreover, SEM and confocal imaging revealed good cell adhesion with a denser cellular layer on the MC® than the NB™ surface. The MC® cytocompatibility was ranked as equivalent to the gold standard implant despite the surface properties differences. These findings provide new insights about the minimally invasive implant’s biological behavior and its potential clinical implication in different implantology situations.  相似文献   
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IntroductionSocio-economic and ethnic background have been discussed as possible risk factors for SARS-CoV-2 infections in children. Improved knowledge could lead to tailored prevention strategies and help improve infection control.AimWe aimed to identify risk factors for SARS-CoV-2 infections in children in the first and second wave of the pandemic.MethodsWe performed an observational population-based cohort study in children (6 months–18 years) scheduled for legally required preventive examination and their parents in a metropolitan region in Germany. Primary endpoint was the SARS-CoV-2 seroconversion rate during the study period. Risk factors assessed included age, pre-existing medical conditions, socio-economic factors and ethnicity.ResultsWe included 2,124 children and their parents. Seroconversion rates among children in all age groups increased 3–4-fold from June 2020 to February 2021. Only 24 of 58 (41%) seropositive children reported symptoms. In 51% of infected children, at least one parent was also SARS-CoV-2-positive. Low level of parental education (OR = 3.13; 95% CI: 0.72–13.69) non-significantly increased the risk of infection. Of the total cohort, 38.5% had a migration background, 9% of Turkish and 5% of Middle Eastern origin, and had the highest risk for SARS-CoV-2 infections (OR = 6.24; 95% CI: 1.38–28.12 and OR = 6.44 (95% CI: 1.14–36.45) after adjustment for other risk factors.ConclusionIn the second half of 2020, seroprevalence for SARS-CoV-2 in children increased especially in families with lower-socioeconomic status. Culture-sensitive approaches are essential to limit transmission and could serve as a blueprint for vaccination strategies.  相似文献   
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Late-stage heart failure and renal dysfunction are often seen in conjunction. Cardiorenal syndrome (CRS) describes the complex interaction between the two disease states. Early literature described the pathophysiology of CRS as related only to reduced cardiac output and decreased renal perfusion. Recent literature suggests a more multifaceted mechanism. Left ventricular assist devices (LVAD), used as bridge-to-transplant and destination therapy in patients with heart failure, impact not only cardiac function but also renal function, especially in those patients with preoperative renal dysfunction. The mechanism by which LVAD implantation affects renal function is complex and understated in early literature. In this review, we discuss the pathogenesis of CRS, the impact of preoperative renal dysfunction in patients undergoing LVAD implantation, and the effect of LVAD implantation on postoperative renal function.  相似文献   
98.
Glomus tumors are mesenchymal tumors commonly seen in the extremities, and rarely seen in deep visceral organs. This is due to the lack of glomus bodies in visceral organs. Here, we describe an unusual association between glomus tumor and co-existing papillary renal cell carcinoma, multiple papillary adenomas, and end stage renal disease. We discuss our diagnostic approach and differential diagnoses, along with an extensive review of all reported benign and malignant primary glomus tumors. A 63-year-old male with a known history of a kidney transplant, end-stage renal disease, and previous nephrectomy of his right kidney due to a renal mass (papillary renal cell carcinoma) presented with a renal mass. Microscopic examination showed papillary carcinoma, multiple papillary adenomas, and a small nodule with uniform, round to oval cells. Immunohistochemical work-up revealed the small nodule to be a glomus tumor. Only 28 cases of primary renal glomus tumors have been reported in the literature. Most were discovered incidentally. None of the reported cases have occurred along with other renal tumors. This is the first case of the unusual combination of primary renal glomus tumor arising in the native kidney of a renal transplant patient with concurrent papillary renal cell carcinoma and multiple papillary adenomas (renal adenomatosis). We also explore the possible genetic basis behind this association.  相似文献   
99.
For the treatment of patients with advanced HER2-negative hormone receptor-positive breast cancer, several substances have been introduced into practice in recent years. In addition, other drugs are under development. A number of studies have been published over the past year which have shown either an advantage for progression-free survival or for overall survival. This review summarizes the latest results, which have been published at current congresses or in specialist journals, and classifies them in the clinical treatment context. In particular, the importance of therapy with CDK4/6 inhibitors – trastuzumab deruxtecan, sacituzumab govitecan and capivasertib – is discussed. For trastuzumab deruxtecan, an overall survival benefit in HER2-negative breast cancer with low HER2 expression (HER2-low expression) was reported in the Destiny-Breast-04 study. Similarly, there was an overall survival benefit in the FAKTION study with capivasertib. The lack of overall survival benefit for palbociclib in the first line of therapy raises the question of clinical classification.Key words: advanced breast cancer, chemotherapy, endocrine therapy, antibody drug conjugates  相似文献   
100.
Staphylococcus aureus is a human and animal pathogen as well as a commensal bacterium. It can be a causative agent of severe, life-threatening infections with high mortality, e.g., toxic shock syndrome, septic shock, and multi-organ failure. S. aureus strains secrete a number of toxins. Exotoxins/enterotoxins are considered important in the pathogenesis of the above-mentioned conditions. Exotoxins, e.g., superantigen toxins, cause uncontrolled and polyclonal T cell activation and unregulated activation of inflammatory cytokines. Here we show the importance of genomic analysis of infectious strains in order to identify disease-causing exotoxins. Further, we show through functional analysis of superantigenic properties of staphylococcal exotoxins that even very small amounts of a putative superantigenic contaminant can have a significant mitogenic effect. The results show expression and production of two distinct staphylococcal exotoxins, SEC and SEL, in several strains from clinical isolates. Antibodies against both toxins are required to neutralise the superantigenic activity of staphylococcal supernatants and purified staphylococcal toxins.  相似文献   
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