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91.
Carmen Andrea Pfortmueller Christian Drexel Simone Kr?henmann-Müller Alexander Benedikt Leichtle Georg Martin Fiedler Gregor Lindner Aristomenis Konstantinos Exadaktylos 《PloS one》2016,11(3)
Background
Major trauma remains one of the principle causes of disability and death throughout the world. There is currently no satisfactory risk assessment to predict mortality in patients with major trauma. The aim of our study is to examine whether S-100 B protein concentrations correlate with injury severity and survival in patients with major trauma, with special emphasis on patients without head injury.Methods
Our retrospective data analysis comprised adult patients admitted to our emergency department between 1.12. 2008 and 31.12 2010 with a suspected major trauma. S-100 B concentrations were routinely assessed in major trauma patients.Results
A total of 27.7% (378) of all patients had major trauma. The median ISS was 24.6 (SD 8.4); 16.6% (63/378) of the patients died. S-100 B concentrations correlated overall with the ISS (p<0.0001). Patients who died had significantly higher S-100 B concentrations than survivors (8.2 μg/l versus 2.2 μg/l, p<0.0001). Polytraumatised patients with and without head trauma did not differ significantly with respect to S-100 B concentration (3.2 μg/l (SD 5.3) versus 2.9 μg/l (SD 3.8), respectively, p = 0.63) or with respect to Injury Severity Score (24.8 (SD 8.6) versus 24.2 (SD 8.1), respectively, p = 0.56). S-100 B concentrations correlated negatively with survival (p<0.0001) in all patients and in both subgroups (p = 0.001 and p = 0.006, respectively)Conclusions
S-100 concentrations on admission correlate positively with greater injury severity and decreased survival in major trauma patients, independently of the presence of a head injury. S-100 B protein levels at admission in patients with major trauma may therefore be used to assess outcome in all polytraumatised patients. These measurements should be subject to further evaluation. 相似文献92.
Elisabeth Lobner Anne-Sophie Humm Georg Mlynek Konstantin Kubinger Michael Kitzmüller Michael W. Traxlmayr 《MABS-AUSTIN》2017,9(7):1088-1104
Fcabs (Fc domain with antigen-binding sites) are promising novel therapeutics. By engineering of the C-terminal loops of the CH3 domains, 2 antigen binding sites can be inserted in close proximity. To elucidate the binding mode(s) between homodimeric Fcabs and small homodimeric antigens, the interaction between the Fcabs 448 and CT6 (having the AB, CD and EF loops and the C-termini engineered) with homodimeric VEGF was investigated. The crystal structures of these Fcabs, which form polymers with the antigen VEGF in solution, were determined. However, construction of heterodimeric Fcabs (JanusFcabs: one chain Fc-wt, one chain VEGF-binding) results in formation of distinct JanusFcab–VEGF complexes (2:1), which allowed elucidation of the crystal structure of the JanusCT6–VEGF complex at 2.15 Å resolution. VEGF binding to Janus448 and JanusCT6 is shown to be entropically unfavorable, but enthalpically favorable. Structure-function relationships are discussed with respect to Fcab design and engineering strategies. 相似文献
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Unbalanced growth induced by depletion of manganese ions was a prerequisite for production of ribonucleotides in a high salt mineral medium with the wildtype strain Brevibacterium ammoniagenes ATCC 6872. The concentration of manganese strictly controlled the overall deoxyribonucleic acid (DNA) synthesis, whereas ribonucleic acid (RNA), protein and cell wall synthesis remained essentially unimpaired in the manganese-lacking cells.The reversibility of inhibition of overall DNA synthesis was shown by enhanced incorporation (up to threefold compared to the cultures supplied with sufficient manganese) of [8-14C] adenine into alkali-stable, trichloroacetic acid-insoluble material after subsequent addition of 10 M MnCl2 to 15 h-old depleted cultures.The results of inhibitor studies on the restoration of overall DNA synthesis due to subsequent addition of manganese ions to depleted cultures suggest that ribonucleotide reduction is the primary target of the manganese starvation during nucleotide fermentation with Brevibacterium ammoniagenes ATCC 6872. 相似文献
96.
Summary The locomotory turns of the beetle Tenebrio molitor were recorded from free walking animals which were held in stationary position and orientation by means of a tread compensator. Striped patterns revolved around an animal elicit optomotor responses which undergo an inversion at smaller stripe widths. The position of the inversion point characterizes the resolving power of the motion detectors, and corresponds to a 6.5° average angle between the optical axes of interacting elements in the motion detecting device. This indirectly determined value is consistent with the anatomically measured 7° average angle between the axes of neighbouring ommatidia in the Tenebrio compound eye. 相似文献
97.
Irene Schaffner Stefan Hofbauer Michael Krutzler Katharina F. Pirker Marzia Bellei Gerhard Stadlmayr Georg Mlynek Kristina Djinovic‐Carugo Gianantonio Battistuzzi Paul G. Furtmüller Holger Daims Christian Obinger 《Molecular microbiology》2015,96(5):1053-1068
It is demonstrated that cyanobacteria (both azotrophic and non‐azotrophic) contain heme b oxidoreductases that can convert chlorite to chloride and molecular oxygen (incorrectly denominated chlorite ‘dismutase’, Cld). Beside the water‐splitting manganese complex of photosystem II, this metalloenzyme is the second known enzyme that catalyses the formation of a covalent oxygen–oxygen bond. All cyanobacterial Clds have a truncated N‐terminus and are dimeric (i.e. clade 2) proteins. As model protein, Cld from Cyanothece sp. PCC7425 (CCld) was recombinantly produced in Escherichia coli and shown to efficiently degrade chlorite with an activity optimum at pH 5.0 [kcat 1144 ± 23.8 s?1, KM 162 ± 10.0 μM, catalytic efficiency (7.1 ± 0.6) × 106 M?1 s?1]. The resting ferric high‐spin axially symmetric heme enzyme has a standard reduction potential of the Fe(III)/Fe(II) couple of ?126 ± 1.9 mV at pH 7.0. Cyanide mediates the formation of a low‐spin complex with kon = (1.6 ± 0.1) × 105 M?1 s?1 and koff = 1.4 ± 2.9 s?1 (KD ~ 8.6 μM). Both, thermal and chemical unfolding follows a non‐two‐state unfolding pathway with the first transition being related to the release of the prosthetic group. The obtained data are discussed with respect to known structure–function relationships of Clds. We ask for the physiological substrate and putative function of these O2‐producing proteins in (nitrogen‐fixing) cyanobacteria. 相似文献
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