University of Hamburg

About: University of Hamburg is a education organization based out in Hamburg, Germany. It is known for research contribution in the topics: Population & Laser. The organization has 45564 authors who have published 89286 publications receiving 2850161 citations. The organization is also known as: Hamburg University.

Painful stimuli evoke different stimulus-response functions in the amygdala, prefrontal, insula and somatosensory cortex: a single-trial fMRI study

Abstract: Only recently have neuroimaging studies moved away from describing regions activated by noxious stimuli and started to disentangle subprocesses within the nociceptive system. One approach to characterizing the role of individual regions is to record brain responses evoked by different stimulus intensities. We used such a parametric single-trial functional MRI design in combination with a thulium:yttrium-aluminium-granate infrared laser and investigated pain, stimulus intensity and stimulus awareness (i.e. pain-unrelated) responses in nine healthy volunteers. Four stimulus intensities, ranging from warm to painful (300-600 mJ), were applied in a randomized order and rated by the subjects on a five-point scale (P0-4). Regions in the dorsolateral prefrontal cortex and the intraparietal sulcus differentiated between P0 (not perceived) and P1 but exhibited no further signal increase with P2, and were related to stimulus perception and subsequent cognitive processing. Signal changes in the primary somatosensory cortex discriminated between non-painful trials (P0 and P1), linking this region to basic sensory processing. Pain-related regions in the secondary somatosensory cortex and insular cortex showed a response that did not distinguish between innocuous trials (P0 and P1) but showed a positive linear relationship with signal changes for painful trials (P2-4). This was also true for the amygdala, with the exception that, in P0 trials in which the stimulus was not perceived (i.e. 'uncertain' trials), the evoked signal changes were as great as in P3 trials, indicating that the amygdala is involved in coding 'uncertainty', as has been suggested previously in relation to classical conditioning.

Maintenance therapy with pemetrexed plus best supportive care versus placebo plus best supportive care after induction therapy with pemetrexed plus cisplatin for advanced non-squamous non-small-cell lung cancer (PARAMOUNT): a double-blind, phase 3, randomised controlled trial.

Abstract: Summary Background Patients with advanced non-squamous non-small-cell lung cancer (NSCLC) benefit from pemetrexed maintenance therapy after induction therapy with a platinum-containing, non-pemetrexed doublet. The PARAMOUNT trial investigated whether continuation maintenance with pemetrexed improved progression-free survival after induction therapy with pemetrexed plus cisplatin. Methods In this double-blind, multicentre, phase 3, randomised placebo-controlled trial, patients with advanced non-squamous NSCLC aged 18 years or older, with no previous systemic chemotherapy for lung cancer, with at least one measurable lesion, and an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 participated. Before randomisation, patients entered an induction phase which consisted of four cycles of induction pemetrexed (500 mg/m 2 ) plus cisplatin (75 mg/m 2 ) on day 1 of a 21-day cycle. Patients who did not progress after completion of four cycles of induction and who had an ECOG performance status of 0 or 1 were stratified according to disease stage (IIIB or IV), ECOG performance status (0 or 1), and induction response (complete or partial response, or stable disease), and randomly assigned (2:1 ratio) to receive maintenance therapy with either pemetrexed (500 mg/m 2 every 21 days) plus best supportive care or placebo plus best supportive care until disease progression. Randomisation was done with the Pocock and Simon minimisation method. Patients and investigators were masked to treatment assignment. The primary endpoint was progression-free survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT00789373. Findings Of the 1022 patients enrolled, 939 participated in the induction phase. Of these, 539 patients were randomly assigned to receive continuation maintenance with pemetrexed plus best supportive care (n=359) or with placebo plus best supportive care (n=180). Among the 359 patients randomised to continuation maintenance with pemetrexed, there was a significant reduction in the risk of disease progression over the placebo group (HR 0·62, 95% CI 0·49–0·79; p vs none in the placebo group) and febrile neutropenia (five [1%] vs none). Discontinuations due to drug-related adverse events occurred in 19 (5%) patients in the pemetrexed group and six (3%) patients in the placebo group. Interpretation Continuation maintenance with pemetrexed is an effective and well tolerated treatment option for patients with advanced non-squamous NSCLC with good performance status who have not progressed after induction therapy with pemetrexed plus cisplatin. Funding Eli Lilly and Company.

Description and performance of track and primary-vertex reconstruction with the CMS tracker

Abstract: A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tt events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p_T > 0.9GeV is 94% for pseudorapidities of |η| < 0.9 and 85% for 0.9 < |η| < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p_T = 100GeV emitted at |η| < 1.4, the resolutions are approximately 2.8% in p_T, and respectively, 10μm and 30μm in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10–12μm in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.

From Self-Organizing Polymers to Nanohybrid and Biomaterials

Abstract: Block copolymers form a large number of superlattices with characteristic dimensions in the range of a few nanometers up to several micrometers by self-organization. The interplay of supramolecular physics and chemistry opens up new approaches to the production of inorganic, organic, and biological structures and to their integration into functional units. Possible applications in the fields of materials science and molecular biology are being investigated. Block copolymers find numerous applications from the production of inorganic nanoparticles (metals, semiconductors, magnets) and mesoporous materials up to take-up/release systems in chemo- and gene therapy.

Cue-induced activation of the striatum and medial prefrontal cortex is associated with subsequent relapse in abstinent alcoholics

Abstract: Animal experiments have provided evidence that the striatum and medial prefrontal cortex play a predominant role in the acquisition and maintenance of drug-seeking behavior. Alcohol-associated stimuli that were regularly paired with alcohol intake may become conditioned cues and elicit a motivational response that triggers relapse in alcohol-dependent patients. We used functional magnetic resonance imaging and visual alcohol-associated and control cues to assess brain activation in ten abstinent alcoholics and control subjects. Patients were followed for 3 months, and alcohol intake was recorded. Alcohol-related versus neutral visual stimuli activated the putamen, anterior cingulate and adjacent medial prefrontal cortex in alcoholics compared with healthy controls. Cue-induced activation of these brain areas was pronounced in the five alcoholics who subsequently relapsed during the observation period. A multiple regression analysis showed that, in alcoholics, the amount of subsequent alcohol intake was associated with the intensity of cue-induced brain activation but not the severity of alcohol craving, amount of previous alcohol intake or duration of abstinence before scanning. This pilot study showed that cue-induced activation of the anterior cingulate, medial prefrontal cortex and striatum may play a role in the attribution of incentive salience to alcohol-associated stimuli, thus increasing the motivational value and attentional processing of alcohol cues. Functional brain imaging may help to identify a group of alcoholics with an otherwise undetected high risk of relapse.