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71.
Yi Su Wendelin Bhm Marco Wenzel Silvia Paasch Margret Acker Thomas Doert Eike Brunner Thomas Henle Jan J. Weigand 《RSC advances》2020,10(73):45116
The increasing concerns on uranium and rare earth metal ion pollution in the environment require sustainable strategies to remove them from wastewater. The present study reports an eco-friendly approach to convert a kind of protein-rich biomass, brewer''s spent grain (BSG), into effective biosorbents for uranyl and rare earth metal ions. The employed method reduces the energy consumption by performing the hydrothermal treatment at a significantly lower temperature (150 °C) than conventional hydrothermal carbonization. In addition, with the aid of the Maillard reaction between carbohydrates and proteins forming melanoidins, further activation processes are not required. Treatment at 150 °C for 16 h results in an altered biosorbent (ABSG) with increased content of carboxyl groups (1.46 mmol g−1) and a maximum adsorption capacity for La3+, Eu3+, Yb3+ (pH = 5.7) and UO22+ (pH = 4.7) of 38, 68, 46 and 221 mg g−1, respectively. Various characterization methods such as FT-IR, 13C CP/MAS NMR, SEM-EDX and STA-GC-MS analysis were performed to characterize the obtained material and to disclose the adsorption mechanisms. Aside from oxygen-containing functional groups, nitrogen-containing functional groups also contribute to the adsorption. These results strongly indicate that mild hydrothermal treatment of BSG could be applied as a greener, low-cost method to produce effective adsorbents for uranyl and rare earth metal ion removal.Effective biosorbent ABSG is obtained via hydrothermal treatment of BSG at low temperature without activation, minimizing energy consumption and environmental impact. 相似文献
72.
Balzar S Strand M Rhodes D Wenzel SE 《The Journal of allergy and clinical immunology》2007,119(4):855-862
BACKGROUND: IgE-mediated responses contribute to allergy and asthma. Little is understood regarding the relationship of tissue IgE to systemic IgE, inflammation or clinical outcomes. OBJECTIVES: To evaluate local IgE expression and cellular inflammation in the proximal and distal lung of normal subjects and subjects with asthma of varying severity and relate those tissue parameters to systemic IgE levels, atopy, lung function, and history of severe exacerbations of asthma. METHODS: Tissue from more than 90 subjects with eosinophilic (SAeo(+)) and noneosinophilic (SAeo(-)) severe asthma, mild asthma and normal subjects were immunostained for IgE, signal-amplifying isoform of IgE receptor (FcepsilonRIbeta) and markers of mast cells, eosinophils, and lymphocytes. Tissue expression of IgE, FcepsilonRIbeta, cellular inflammation, serum IgE, and atopy were compared. Regression models were used to determine the relationship of local and systemic IgE to lung function and severe exacerbations of asthma. RESULTS: Mast cell-bound IgE was present along airways but absent in lung parenchyma. Although the groups were similar in systemic/serum IgE and atopy, local/tissue IgE was highest in SAeo(+) and correlated with eosinophils and lymphocytes (r(s) = 0.52, P < .0001; and r(s) = 0.23, P = .03, respectively). Higher local IgE was associated with better lung function, but also with more severe exacerbations of asthma. CONCLUSION: Local IgE appears to be primarily a component of responses within the mucosal immune compartment and is related to cellular inflammation, lung function, and clinical outcomes in asthma. CLINICAL IMPLICATIONS: Local/airway IgE-related processes rather than systemic markers of atopy may be relevant in determining clinical outcomes in asthma. 相似文献
73.
Hardy Weisshoff Katrin Wenzel Sarah Schulze-Rothe Heike Nikolenko Hanna Davideit Niels-Peter Becker Peter Göttel G. Susan Srivatsa Margitta Dathe Johannes Müller Annekathrin Haberland 《Journal of pharmaceutical sciences》2018,107(8):2033-2041
Possible unwanted folding of biopharmaceuticals during manufacturing and storage has resulted in analysis schemes compared to small molecules that include bioanalytical characterization besides chemical characterization. Whether bioanalytical characterization is required for nucleotide-based drugs, may be decided on a case-by-case basis. Nucleotide-based pharmaceuticals, if chemically synthesized, occupy an intermediate position between small-molecule drugs and biologics. Here, we tested whether a physicochemical characterization of a nucleotide-based drug substance, BC 007, was adequate, using circular dichroism (CD) spectroscopy. Nuclear magnetic resonance confirmed CD data in one experimental setup. BC 007 forms a quadruplex structure under specific external conditions, which was characterized for its stability and structural appearance also after denaturation using CD and nuclear magnetic resonance. The amount of the free energy (ΔG0) involved in quadruplex formation of BC 007 was estimated at +8.7 kJ/mol when dissolved in water and +1.4 kJ/mol in 154 mM NaCl, indicating structural instability under these conditions. However, dissolution of the substance in 5 mM of KCl reduced the ΔG0 to ?5.6 kJ/mol due to the stabilizing effect of cations. These results show that positive ΔG0 of quadruplex structure formation in water and aqueous NaCl prevents BC 007 from preforming stable 3-dimensional structures, which could potentially affect drug function. 相似文献
74.
75.
Neurauter A Kramer-Johansen J Eilevstjønn J Myklebust H Wenzel V Lindner KH Eftestøl T Steen PA Strohmenger HU 《Resuscitation》2007,73(2):246-252
The duration of untreated ventricular fibrillation (VF) is of paramount importance for CPR success. Moreover, therapeutic interventions taking into account the interval between cardiac arrest onset and initiation of CPR improve outcome. This study was performed to investigate whether VF feature analysis could be used to estimate the duration of VF in patients with out-of-hospital cardiac arrest. Demographic data recorded according to the Utstein guidelines and ECG recordings of 376 cardiac arrest patients from three European areas were analysed. Ten features in the time and frequency domain derived from different sub-bands of the initial VF ECG (n=127) were evaluated. The correlation between VF ECG features and cardiac arrest times was investigated using Pearson's correlation coefficient in a subset of 40 patients with reliably estimated downtimes and artefact-free initial VF tracings. No significant correlation (p<.05) between any of the VF ECG features and downtime could be found. The duration of cardiac arrest could not be estimated reliably from human VF ECG single feature analysis. 相似文献
76.
77.
Rossmann H Büchler E Wenzel JJ Neukirch C du Prel JB Lackner KJ 《Clinical chemistry》2007,53(5):980-982
BACKGROUND: Allele frequencies of single-nucleotide polymorphisms (SNPs) can be quantified from DNA pools. The conventional preparation of DNA pools requires DNA isolation and quantification for each blood sample. We hypothesized that pooling of whole blood samples according to their leukocyte count, which determines DNA content, would be as reliable as the conventional pooling method but much less tedious to perform. METHODS: We collected 100 whole blood samples and measured the leukocyte count. Samples were frozen until further use. After thawing, pools were generated by combining aliquots containing an equal number of leukocytes. In parallel, DNA was extracted from another aliquot, DNA concentration was measured, and DNA concentration-based pools were assembled. All original samples were genotyped directly using 4 different SNP assays to obtain the exact allele frequencies in the pool. In addition, samples of known genotypes were mixed according to the DNA concentration or the leukocyte count to generate artificial samples of known allele frequencies. We analyzed pools and mixes in triplicate by pyrosequencing and calculated allelic frequencies. RESULTS: Leukocyte and DNA pooling provided equally accurate and precise SNP frequencies comparable to published data. CONCLUSION: DNA and leukocyte pooling are both suitable strategies to determine allele frequencies in frozen samples. The leukocyte pooling approach is much less tedious, quicker, and less expensive. It should be always considered if leukocyte counts are available. 相似文献
78.
Background and objective: Because of the unique pharmacology and clinical versatility of botulinum toxin (BoNT), particularly BoNT serotype A (BoNTA), a need exists for discussion of the current data on similarities and differences between two BoNTA products, BOTOX and Dysport. Methods: We compared the physiochemical and pharmacological properties of BOTOX and Dysport using information from the Summary of Product Characteristics (SmPC) documents from a number of countries around the world. Results and discussion: Our analysis based on the SmPC documents demonstrated distinct differences in physical characteristics, breadth of approved indications, dosing and administration, and the incidence and severity of adverse events. Conclusion: BOTOX and Dysport are not bioequivalent. Many of the differences between BOTOX and Dysport discussed within are probably related to the differences in their physical characteristics. 相似文献
79.
Die Anaesthesiologie - 相似文献
80.
The pathogenesis of venous thromboembolism (VTE) is still not completely understood. Experimental animals in which human deep vein thrombosis can be modeled are useful tools to investigate the pathogenesis of VTE. Besides the availability of transgenic and genetically modified mice, the use of high frequency ultrasound and intravital microscopy plays an important role in identifying thrombotic processes in mouse models. In this article, an overview about the application of various new technologies and existing mouse models is provided, and the impact of venous side branches on deep vein thrombosis in the mouse model is discussed. 相似文献