An Economical and Versatile High-Throughput Protein Purification System Using a Multi-Column Plate Adapter.

Protein purification is imperative to the study of protein structure and function and is usually used in combination with biophysical techniques. It is also a key component in the development of new therapeutics. The evolving era of functional proteomics is fueling the demand for high-throughput protein purification and improved techniques to facilitate this. It was hypothesized that a multi column plate adaptor (MCPA) can interface multiple chromatography columns of different resins with multi-well plates for parallel purification. This method offers an economical and versatile method of protein purification that can be used under gravity or vacuum, rivaling the speed of an automated system. The MCPA can be used to recover milligram yields of protein by an affordable and time efficient method for subsequent characterization and analysis. The MCPA has been used for high-throughput affinity purification of SH3 domains. Ion exchange has also been demonstrated via the MCPA to purify protein post Ni-NTA affinity chromatography, indicating how this system can be adapted to other purification types. Due to its setup with multiple columns, individual customization of parameters can be made in the same purification, unachievable by the current plate-based methods.

Effect of acute psychosocial stress on the brain-derived neurotrophic factor in humans - a randomized cross within trial.

The brain-derived neurotrophic factor (BDNF) is involved in the plasticity and development of the central nervous system. Thereby the protein synthesis is highly related to neuronal activity, and its signaling pathways are associated with several substances like, e.g. glucocorticoids, which seem to be able to activate BDNF-Tropomyosin receptor kinase B (TrkB). While there is evidence that acute physical stress can result in advantageous physiological outcomes like an enhanced BDNF level, outcome parameters in response to psychosocial stress are primarily focused on psychological parameters. The existing literature pointing on the impact of acute psychosocial stress on physiological parameters is controversial and differs depending on the species, the stressor used, and the study methodology. It was hypothesized that an acute standardized psychosocial stressor would increase the BDNF level and therefore show beneficial physiological outcome parameters through psychosocial stress. The serum BDNF levels of 32 healthy young males (M = 24.31 years of age, SD = 3.35), who performed the Trier Social Stress Test (TSST), were assessed and compared to a control condition. To prove the stress-generating effect of the TSST, additional cortisol levels were measured. Acute psychosocial stress significantly increased the serum BDNF- and the cortisol-level, whereby no alteration was found during the control. This study expands the rare literature focusing on the effect of an acute standardized psychosocial stressor on the BDNF level in healthy humans, including a control condition. Implications for future studies are being discussed.

Effects of psychosocial and physical stress on lactate and anxiety levels.

Both intense physical activity and potent psychosocial stressors increase blood lactate. Raising lactate levels by infusing the chemical can have an anxiogenic effect. Here, we compare the relationship between changes in lactate and anxiety levels resulting from two standardized stressors. We investigated the effects of the Multiple Wingate All-Out Performance Test (WG), a strong physical stressor, and the Trier Social Stress Test (TSST), a well-documented psychosocial stressor, in 32 healthy young men using a crossover design. Before and after each stressor, venous blood was analyzed for lactate levels and the State-Trait-Anxiety Inventory (STAI) was given. Both stressors raised both lactate and anxiety significantly above their baseline levels. While the rise in lactate was much higher for the WG than for the TSST, the rises in anxiety were nearly equal. Individual fitness did not influence the results for lactate or anxiety. No significant relation between lactate and anxiety changes were found. Thus, our results as well as the literature suggest that lactate is an important variable for understanding the impact of sport participation.

Effects of Cycling and Exergaming on Neurotrophic Factors in Elderly Type 2 Diabetic Men - A Preliminary Investigation.

Patients with type 2 diabetes mellitus (T2DM) are at increased risk of developing neurodegenerative diseases. There is growing evidence that repeated exercise-induced transient increases in neurotrophic factors can augment neurogenesis and neuroplasticity. This pilot study compares the effects of 30-min submaximal cycling with those of exergaming (combining exercise and video gaming) at the same duration and same rating of perceived exertion (BORG RPE: 14-15) on serum neurotrophic factors in 8 elderly non-insulin-dependent T2DM patients (71±4 years) (2×2 crossover design). Brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF) and insulin-like growth factor (IGF)-1 levels were quantified using enzyme-linked immunosorbent assay (ELISA) kits. Heart rates were almost equal during cycling and exergaming, while lactate values were significantly higher during cycling (cycling versus exergaming: 3.7±1.1 versus 2.5±1.2 mmol/l, p<0.05). BDNF and VEGF levels were increased significantly post-cycling (+20%,+14%, p<0.05). No other significant pre-post changes were evident. This study demonstrates that acute exercise can increase neurotrophic factors (BDNF, VEGF) in elderly T2DM patients, depending on exercise mode.