[Cerebral metabolic changes and chronic back pain: Study taking into consideration clinical and psychological parameters]. / Hirnmetabolische Veränderungen bei chronischem Rückenschmerz : Studie unter Berücksichtigung von klinischen und psychischen Parametern.

BACKGROUND: The manifestation of chronic pain and psychological impairments are related to alterations of neurotransmitter metabolism in cerebral pain processing regions, e.g., anterior cingular cortex (ACC), insula. Magnetic resonance spectroscopy ((1)H-MRS) enables in vivo quantification of neurotransmitters in the brain and was applied in this study to examine the hypothesized chronic pain-related imbalance between excitatory (glutamatergic) and inhibitory (GABA-ergic) neurotransmitter turnovers in the brain of patients with nonspecific chronic pain. MATERIALS AND METHODS: A total of 19 patients with nonspecific chronic (> 3 months) back pain and 19 age- and gender-matched healthy subjects participated in this study. Glutamate and GABA as well as glutamate/GABA ratios were determined in the ACC and insula using (1)H-MRS. Sociodemographic, psychological, and pain-related features were measured with standardized questionnaires. RESULTS: There was a strong variance of glutamate/GABA ratios for both patients and healthy subjects with no significant difference between the two groups. Regression analysis revealed certain significant predictors, such as anxiety as causal variable for reduced glutamate and depression and age as predictors for reduced GABA in ACC. In the patient group, intensity of pain was a significant predictor for glutamate and GABA levels in the insula. CONCLUSIONS: Despite the uniform diagnosis of nonspecific chronic back pain, we observed a strong variance of neurotransmitters in cerebral pain processing regions. It is necessary to include psychological as well as clinical parameters (e.g., intensity of pain or depression) for a proper interpretation of neurotransmitter turnovers.

Evidence for gravitational lensing of the cosmic microwave background polarization from cross-correlation with the cosmic infrared background.

We reconstruct the gravitational lensing convergence signal from cosmic microwave background (CMB) polarization data taken by the Polarbear experiment and cross-correlate it with cosmic infrared background maps from the Herschel satellite. From the cross spectra, we obtain evidence for gravitational lensing of the CMB polarization at a statistical significance of 4.0σ and indication of the presence of a lensing B-mode signal at a significance of 2.3σ. We demonstrate that our results are not biased by instrumental and astrophysical systematic errors by performing null tests, checks with simulated and real data, and analytical calculations. This measurement of polarization lensing, made via the robust cross-correlation channel, not only reinforces POLARBEAR auto-correlation measurements, but also represents one of the early steps towards establishing CMB polarization lensing as a powerful new probe of cosmology and astrophysics.

[Evaluation of the German new back school: muscular physiological characteristics]. / Evaluation der Neuen Rückenschule : Muskulär-physiologische Merkmale.

BACKGROUND: According to the biopsychosocial approach of the German new back school the core objectives are sustainable improvement of physical and psychosocial health resources. Subjects with non-specific low back pain were investigated to evaluate the desired physical effects. METHODS: Coordinative and postural motor exercises were evaluated by means of surface electromyography (EMG). Applying a modified waiting group design 56 participants were examined 3 months before the start, at the beginning and at the end of the new back school program as well as 3 and 12 months after completion and the results were compared to a healthy control group (n=56) matched for age and body mass index (BMI). RESULTS: Initially significant group differences were found in 18 % of all statistical calculations of the static and 6 % of the dynamic test situations. Considering the trunk muscles the most frequent significant alterations from normative data were found in the lumbar multifidus muscle (static tests 29 % and dynamic tests 7 %). No relevant changes in the number of statistical results could be detected directly after completion of the new back school program. Nevertheless, at 12 months follow-up the number of significant differences to the normative data of the control group dropped by one third to 12 % of all calculations with static loads. CONCLUSION: The adjustment effects at 12 months follow-up indicate a delayed positive influence of the new back school program on muscular physiological parameters. Individuals with chronic non-specific back pain showed a long-term profit from participation in the new back school program due to the initiated orientation to a modified more active lifestyle.

[Evaluation of the German new back school: pain-related and psychological characteristics]. / Evaluation der Neuen Rückenschule : Schmerz- und psychologische Merkmale.

BACKGROUND: Results related to the outcome of the classical back schools are inconsistent. Accordingly, a reformulation of the program integrating psychological and social aspects was performed as a necessary step for the development of the new back school in Germany. The aim of this study was to assess the effectiveness and sustainability of the new back school in subjects with non-specific back pain in the prevention setting. MATERIAL AND METHODS: In a modified waiting design, individuals were investigated with respect to demographical, pain-related and psychological characteristics 3 months before the start, at the start and at the end of the back school and as well as 12 months after completion. In addition, predictors for a successful participation were analyzed. RESULTS: A total of 88 subjects with back pain initially participated in the study. In the short and long-term course, low to moderate effects were detected; however, during follow-up a reduction of pain showed high effects. Depression as assessed by the hospital anxiety and depression scale (HADS) and passive coping strategies assessed using the coping strategies questionnaire (CSQ) were identified as predictors for response to the intervention. CONCLUSION: On the basis of the sample studied, the new back school proved to be an effective treatment for short and long-term reduction of pain-related stress and associated psychological aspects. Maladaptive, passive coping strategies and higher depression scores were associated with a higher probability of success in terms of pain reduction and functional improvement.