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Background: Patients with advanced stage non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC) often experience multidimensional impairments, affecting quality of life during their course of disease. In lung cancer patients with operable disease, several studies have shown that exercise has a positive impact on quality of life and physical functioning. There is limited evidence regarding efficacy for advanced lung cancer patients undergoing palliative treatment. Therefore, the POSITIVE study aims to evaluate the benefit of a 24-week exercise intervention during palliative treatment in a randomized controlled setting., Methods/design: The POSITIVE study is a randomized, controlled trial investigating the effects of a 24-week exercise intervention during palliative treatment on quality of life, physical performance and immune function in advanced, non-operable lung cancer patients. 250 patients will be recruited in the Clinic for Thoracic Diseases in Heidelberg, enrolment begun in November 2013. Main inclusion criterion is histologically confirmed NSCLC (stage IIIa, IIIb, IV) or SCLC (Limited Disease-SCLC, Extensive Disease-SCLC) not amenable to surgery. Patients are randomized into two groups. Both groups receive weekly care management phone calls (CMPCs) with the goal to assess symptoms and side effects. Additionally, one group receives a combined resistance and endurance training (3x/week). Primary endpoints are quality of life assessed by the Functional Assessment of Cancer Therapy for patients with lung cancer (FACT-L, subcategory Physical Well-Being) and General Fatigue measured by the Multidimensional Fatigue Inventory (MFI-20). Secondary endpoints are physical performance (maximal voluntary isometric contraction, 6-min walk distance), psychosocial (depression and anxiety) and immunological parameters and overall survival., Discussion: The aim of the POSITIVE trial is the evaluation of effects of a 24-week structured and guided exercise intervention during palliative treatment stages. Analysis of various outcomes (such as quality of life, physical performance, self-efficacy, psychosocial and immunological parameters) will contribute to a better understanding of the potential of exercise in advanced lung cancer patients. In contrast to other studies with advanced oncological patients the POSITIVE trial provides weekly phone calls to support patients both in the intervention and control group and to segregate the impact of physical activity on quality of life., Trial Registration: ClinicalTrials.gov NCT02055508 (Date: December 12, 2013).

In computational neuroscience it is generally accepted that human motor memory contains neural representations of the physics of the musculoskeletal system and the objects in the environment. These representations are called "internal models". Force field studies, in which subjects have to adapt to dynamic perturbations induced by a robotic manipulandum, are an established tool to analyze the characteristics of such internal models. The aim of the current study was to investigate whether catch trials during force field learning could influence the consolidation of motor memory in more complex tasks. Thereby, the force field was more than double the force field of previous studies (35 N·s/m). Moreover, the arm of the subjects was not supported. A total of 46 subjects participated in this study and performed center-out movements at a robotic manipulandum in two different force fields. Two control groups learned force field A on day 1 and were retested in the same force field on day 3 (AA). Two test groups additionally learned an interfering force field B (= -A) on day 2 (ABA). The difference between the two test and control groups, respectively, was the absence (0%) or presence (19%) of catch trials, in which the force field was turned-off suddenly. The results showed consolidation of force field A on day 3 for both control groups. Test groups showed no consolidation of force field A (19% catch trials) and even poorer performance on day 3 (0% catch trials). In conclusion, it can be stated that catch trials seem to have a positive effect on the performance on day 3 but do not trigger a consolidation process as shown in previous studies that used a lower force field viscosity with supported arm. These findings indicate that the results of previous studies in which less complex tasks were analyzed, cannot be fully transferred to more complex tasks. Moreover, the effects of catch trials in these situations are insufficiently understood and further research is needed.

Determination of erythrocyte acetylcholinesterase (AChE) activity is the appropriate tool for the diagnosis of organophosphate exposure and intoxication. The original colorimetric Ellman procedure is disturbed by a high hemoglobin absorption at 412 nm. In our modified method the wavelength was changed to 436 nm. This reduced the indicator absorption to 80% and the hemoglobin absorption to 25%. The signal-to-noise ratio was further enhanced by reduction of pH and substrate concentration, thus making it possible to measure 3% residual activity. AChE activity was determined in whole blood samples in the presence of the selective butyrylcholinesterase inhibitor ethopropazine. Dilution of blood samples (1:100) stops secondary reactions in the presence of inhibitor (organophosphate) and reactivator (oxime). Normalization of the AChE activity to the hemoglobin content, determined as cyanmethemoglobin, prevented dilution errors. This modified approach provides a simple way for sensitive and precise determination of AChE activity in whole blood in the presence of organophosphates even with low-tech equipment.

Human poisoning by organophosphates bearing two methoxy groups, e.g. by malathion, paraoxon-methyl, dimethoate and oxydemeton-methyl, is generally considered to be rather resistant to oxime therapy. Since the oxime effectiveness is influenced not only by its reactivating potential but also by inhibition, aging and spontaneous reactivation kinetics, experiments were performed with human acetyl- (AChE) and butyrylcholinesterase (BChE) to determine the respective kinetic constants. The efficacy of obidoxime in reactivating dimethylphosphoryl-AChE was 40, 9 and 3 times higher than of HI 6, pralidoxime and HLö 7, respectively. Aging (t1/2 3.7 h) and spontaneous reactivation (t1/2 0.7 h) occurred concomitantly, with the portion of the aged enzyme being dependent on the presence of excess inhibitor. Calculation of steady-state AChE activity in the presence of inhibitor and oxime revealed that obidoxime was superior to pralidoxime. In addition, organophosphate concentrations up to 10(-6) M (paraoxon-methyl) and 10(-4) M (oxydemeton-methyl) could be counteracted at clinically relevant oxime concentrations (10 microM). These data indicate that oximes may effectively reactivate human dimethylphosphoryl-AChE. Failure of oximes may be attributed to megadose intoxications and to prolonged time intervals between poison uptake and oxime administration. The potency of the oximes to reactivate dimethylphosphoryl-BChE was much lower and the spontaneous reactivation slower (t1/2 9 h), while aging proceeded at a comparable rate. Thus, BChE activity determination for diagnosis and therapeutic monitoring may give no reliable information on AChE status.