244 resultados para Ralf Wunderlich


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Land use science has traditionally used case-study approaches for in-depth investigation of land use change processes and impacts. Meta-studies synthesize findings across case-study evidence to identify general patterns. In this paper, we provide a review of meta-studies in land use science. Various meta-studies have been conducted, which synthesize deforestation and agricultural land use change processes, while other important changes, such as urbanization, wetland conversion, and grassland dynamics have hardly been addressed. Meta-studies of land use change impacts focus mostly on biodiversity and biogeochemical cycles, while meta-studies of socioeconomic consequences are rare. Land use change processes and land use change impacts are generally addressed in isolation, while only few studies considered trajectories of drivers through changes to their impacts and their potential feedbacks. We provide a conceptual framework for linking meta-studies of land use change processes and impacts for the analysis of coupled human–environmental systems. Moreover, we provide suggestions for combining meta-studies of different land use change processes to develop a more integrated theory of land use change, and for combining meta-studies of land use change impacts to identify tradeoffs between different impacts. Land use science can benefit from an improved conceptualization of land use change processes and their impacts, and from new methods that combine meta-study findings to advance our understanding of human–environmental systems.

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For perceptual-cognitive skill training, a variety of intervention methods has been proposed, including the so-called “color-cueing method” which aims on superior gaze-path learning by applying visual markers. However, recent findings challenge this method, especially, with regards to its actual effects on gaze behavior. Consequently, after a preparatory study on the identification of appropriate visual cues for life-size displays, a perceptual-training experiment on decision-making in beach volleyball was conducted, contrasting two cueing interventions (functional vs. dysfunctional gaze path) with a conservative control condition (anticipation-related instructions). Gaze analyses revealed learning effects for the dysfunctional group only. Regarding decision-making, all groups showed enhanced performance with largest improvements for the control group followed by the functional and the dysfunctional group. Hence, the results confirm cueing effects on gaze behavior, but they also question its benefit for enhancing decision-making. However, before completely denying the method’s value, optimisations should be checked regarding, for instance, cueing-pattern characteristics and gaze-related feedback.

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BACKGROUND Skull-base chondrosarcoma (ChSa) is a rare disease, and the prognostication of this disease entity is ill defined. METHODS We assessed the long-term local control (LC) results, overall survival (OS), and prognostic factors of skull-base ChSa patients treated with pencil beam scanning proton therapy (PBS PT). Seventy-seven (male, 35; 46%) patients with histologically confirmed ChSa were treated at the Paul Scherrer Institute. Median age was 38.9 years (range, 10.2-70.0y). Median delivered dose was 70.0 GyRBE (range, 64.0-76.0 GyRBE). LC, OS, and toxicity-free survival (TFS) rates were calculated using the Kaplan Meier method. RESULTS After a mean follow-up of 69.2 months (range, 4.6-190.8 mo), 6 local (7.8%) failures were observed, 2 of which were late failures. Five (6.5%) patients died. The actuarial 8-year LC and OS were 89.7% and 93.5%, respectively. Tumor volume > 25 cm(3) (P = .02), brainstem/optic apparatus compression at the time of PT (P = .04) and age >30 years (P = .08) were associated with lower rates of LC. High-grade (≥3) radiation-induced toxicity was observed in 6 (7.8%) patients. The 8-year high-grade TFS was 90.8%. A higher rate of high-grade toxicity was observed for older patients (P = .073), those with larger tumor volume (P = .069), and those treated with 5 weekly fractions (P = .069). CONCLUSIONS This is the largest PT series reporting the outcome of patients with low-grade ChSa of the skull base treated with PBS only. Our data indicate that protons are both safe and effective. Tumor volume, brainstem/optic apparatus compression, and age were prognosticators of local failures.

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BACKGROUND Parameningeal rhabdomyosarcomas (PM-RMSs) represent approximately 25% of all rhabdomyosarcoma (RMS) cases. These tumors are associated with early recurrence and poor prognosis. This study assessed the clinical outcome and late toxicity of pencil beam scanning (PBS) proton therapy (PT) in the treatment of children with PM-RMS. PROCEDURES Thirty-nine children with PM-RMS received neoadjuvant chemotherapy followed by PBS-PT at the Paul Scherrer Institute, with concomitant chemotherapy. The median age was 5.8 years (range, 1.2-16.1). Due to young age, 25 patients (64%) required general anesthesia during PT. The median time from the start of chemotherapy to PT was 13 weeks (range, 3-23 weeks). Median prescription dose was 54 Gy (relative biologic effectiveness, RBE). RESULTS With a mean follow-up of 41 months (range, 9-106 months), 10 patients failed. The actuarial 5-year progression-free survival (PFS) was 72% (95% CI, 67-94%) and the 5-year overall survival was 73% (95% CI, 69-96%). On univariate analysis, a delay in the initiation of PT (>13 weeks) was a significant detrimental factor for PFS. Three (8%) patients presented with grade 3 radiation-induced toxicity. The estimated actuarial 5-year toxicity ≥grade 3 free survival was 95% (95% CI, 94-96%). CONCLUSIONS Our data contribute to the growing body of evidence demonstrating the safety and effectiveness of PT for pediatric patients with PM-RMS. These preliminary results are encouraging and in line with other combined proton-photon and photons series; observed toxicity was acceptable.

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OBJECTIVE The purpose of this study was to examine the recurrence rate of wound rupture in primary pilonidal sinus disease (PSD) after median closure. SUBJECTS AND METHODS A total of 583 patients from the German military cohort were interviewed. We compared the choice of surgical therapy, wound dehiscence (if present) and long-term recurrence-free survival for patients with primary open treatment, marsupialization and primary median treatment (closed vs. secondary open, respectively). Actuarial recurrence rate was determined using the Kaplan-Meier calculation with a follow-up of up to 20 years after primary PSD surgery. RESULTS Patients with excision followed by primary open wound treatment showed a significantly lower 5- than 10-year recurrence rate (8.3 vs. 11.2%) compared to the patients with primary midline closure (17.4 vs. 20.5%, p = 0.03). The 20-year recurrence rate was 28% in primary open wound treatment versus 44% in primary midline closure without wound rupture. In contrast to these findings, long-term recurrence rates following secondary open wound treatment (12.2% at 5 years vs. 17.1% at 10 years) tended to be higher (although not significantly, p = 0.57) compared to primary open treatment (8.3% at 5 years vs. 11.2% at 10 years). There was no statistical difference in long-term recurrence rates between secondary open and primary midline closure (p = 0.7). Hence, despite only a short wound closure time experienced before wound rupture, the patient does not fully benefit from an open wound treatment in terms of recurrence rate. CONCLUSION The postoperative pilonidal sinus wound rupture of primary midline closures did not significantly increase the 5- and 10-year long-term recurrence rates compared to uneventfully healing primary midline closures.

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OBJECTIVE Endoscopic lung volume reduction (ELVR) with valves has been shown to improve COPD patients with severe emphysema. However, a major complication is pneumothoraces, occurring typically soon after valve implantation, with severe consequences if not managed promptly. Based on the knowledge that strain activity is related to a higher risk of pneumothoraces, we asked whether modifying post-operative medical care with the inclusion of strict short-term limitation of strain activity is associated with a lower incidence of pneumothorax. METHODS Seventy-two (72) emphysematous patients without collateral ventilation were treated with bronchial valves and included in the study. Thirty-two (32) patients received standard post-implantation medical management (Standard Medical Care (SMC)), and 40 patients received a modified medical care that included an additional bed rest for 48 hours and cough suppression, as needed (Modified Medical Care (MMC)). RESULTS The baseline characteristics were similar for the two groups, except there were more males in the SMC cohort. Overall, ten pneumothoraces occurred up to four days after ELVR, eight pneumothoraces in the SMC, and only two in the MMC cohorts (p=0.02). Complicated pneumothoraces and pneumothoraces after upper lobe treatment were significantly lower in MMC (p=0.02). Major clinical outcomes showed no significant differences between the two cohorts. CONCLUSIONS In conclusion, modifying post-operative medical care to include bed rest for 48 hours after ELVR and cough suppression, if needed, might reduce the incidence of pneumothoraces. Prospective randomized studies with larger numbers of well-matched patients are needed to confirm the data.

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PURPOSE To evaluate the utility of attenuation correction (AC) of V/P SPECT images for patients with pulmonary emphysema. MATERIALS AND METHODS Twenty-one patients (mean age 67.6 years) with pulmonary emphysema who underwent V/P SPECT/CT were included. AC/non-AC V/P SPECT images were compared visually and semiquantitatively. Visual comparison of AC/non-AC images was based on a 5-point likert scale. Semiquantitative comparison assessed absolute counts per lung (aCpLu) and lung lobe (aCpLo) for AC/non-AC images using software-based analysis; percentage counts (PC = (aCpLo/aCpLu) × 100) were calculated. Correlation between AC/non-AC V/P SPECT images was analyzed using Spearman's rho correlation coefficient; differences were tested for significance with the Wilcoxon rank sum test. RESULTS Visual analysis revealed high conformity for AC and non-AC V/P SPECT images. Semiquantitative analysis of PC in AC/non-AC images had an excellent correlation and showed no significant differences in perfusion (ρ = 0.986) or ventilation (ρ = 0.979, p = 0.809) SPECT/CT images. CONCLUSION AC of V/P SPECT images for lung lobe-based function imaging in patients with pulmonary emphysema do not improve visual or semiquantitative image analysis.

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INTRODUCTION Clinical treatment of spinal metastasis is gaining in complexity while the underlying biology remains unknown. Insufficient biological understanding is due to a lack of suitable experimental animal models. Intercellular adhesion molecule-1 (ICAM1) has been implicated in metastasis formation. Its role in spinal metastasis remains unclear. It was the aim to generate a reliable spinal metastasis model in mice and to investigate metastasis formation under ICAM1 depletion. MATERIAL AND METHODS B16 melanoma cells were infected with a lentivirus containing firefly luciferase (B16-luc). Stable cell clones (B16-luc) were injected retrogradely into the distal aortic arch. Spinal metastasis formation was monitored using in vivo bioluminescence imaging/MRI. Neurological deficits were monitored daily. In vivo selected, metastasized tumor cells were isolated (mB16-luc) and reinjected intraarterially. mB16-luc cells were injected intraarterially in ICAM1 KO mice. Metastasis distribution was analyzed using organ-specific fluorescence analysis. RESULTS Intraarterial injection of B16-luc and metastatic mB16-luc reliably induced spinal metastasis formation with neurological deficits (B16-luc:26.5, mB16-luc:21 days, p<0.05). In vivo selection increased the metastatic aggressiveness and led to a bone specific homing phenotype. Thus, mB16-luc cells demonstrated higher number (B16-luc: 1.2±0.447, mB16-luc:3.2±1.643) and increased total metastasis volume (B16-luc:2.87±2.453 mm3, mB16-luc:11.19±3.898 mm3, p<0.05) in the spine. ICAM1 depletion leads to a significantly reduced number of spinal metastasis (mB16-luc:1.2±0.84) with improved neurological outcome (29 days). General metastatic burden was significantly reduced under ICAM1 depletion (control: 3.47×10(7)±1.66×10(7); ICAM-1-/-: 5.20×10(4)±4.44×10(4), p<0.05 vs. control) CONCLUSION Applying a reliable animal model for spinal metastasis, ICAM1 depletion reduces spinal metastasis formation due to an organ-unspecific reduction of metastasis development.

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Fertility-preservation techniques for medical reasons are increasingly offered in national networks. Knowledge of the characteristics of counselled patients and techniques used are essential. The FertiPROTEKT network registry was analysed between 2007 and 2013, and included up to 85 university and non-university centres in Germany, Austria and Switzerland; 5159 women were counselled and 4060 women underwent fertility preservation. In 2013, fertility-preservation counselling for medical reasons increased significantly among nullipara and women aged between 21 and 35 years (n = 1043; P < 0.001). Frequency of GnRH applications slowly decreased, whereas tissue, oocytes and zygote cryopreservation increased. In 2013, women with breast cancer mainly opted for tissue freezing, whereas women with lymphoma opted for GnRH agonist. Women younger than 20 years predominantly opted for GnRH agonists and ovarian tissue cryopreservation; women aged between 20 and 40 years underwent a variety of techniques; and women over 40 years opted for GnRH agonists. The average number of aspirated oocytes per stimulation cycle decreased as age increased (< 30 years: 12.9; 31-35 years: 12.3; 36-46: 9.0; > 41 years: 5.7). For ovarian tissue cryopreservation, removal and cryopreservation of fewer than one ovary was preferred and carried out in 97% of cases in 2013.

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OBJECTIVE To systematically review the reporting of MII (MII) oocyte development after xenotransplantation of human ovarian tissue. DESIGN Systematic review in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). SETTING Not applicable. PATIENT(S) Not applicable. INTERVENTION(S) Formation of MII oocytes after xenotransplantation of human ovarian tissue. MAIN OUTCOME MEASURE(S) Any outcome reported in Pubmed. RESULT(S) Six publications were identified that report on formation of MII oocytes after xenotransplantation of human ovarian tissue. CONCLUSION(S) Xenografting of human ovarian tissue has proved to be a useful model for examining ovarian function and follicle development in vivo. With human follicles that have matured through xenografting, the possibility of cancer transmission and relapse can also be eliminated, because cancer cells are not able to penetrate the zona pellucida. The reported studies have demonstrated that xenografted ovarian tissue from a range of species, including humans, can produce antral follicles that contain mature (MII) oocytes, and it has been shown that mice oocytes have the potential to give rise to live young. Although some ethical questions remain unresolved, xenotransplantation may be a promising method for restoring fertility. This review furthermore describes the value of xenotransplantation as a tool in reproductive biology and discusses the ethical and potential safety issues regarding ovarian tissue xenotransplantation as a means of recovering fertility.

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Sepsis is a major cause for death worldwide. Numerous interventional trials with agents neutralizing single pro-inflammatory mediators have failed to improve survival in sepsis and aseptic systemic inflammatory response syndromes. This failure could well be explained by the widespread gene expression dysregulation known as "genomic storm" in these patients. A multifunctional polyspecific therapeutic agent might be needed to thwart the effects of this "storm". Licensed pooled intravenous immunoglobulin preparations seemed to be a promising candidate but they have also failed in their present form to prevent sepsis-related death. We report here the protective effect of a single dose of intravenous immunoglobulin preparations with additionally enhanced polyspecificity in three models of sepsis and aseptic systemic inflammation. The modification of the pooled immunoglobulin G molecules by exposure to ferrous ions resulted in their newly acquired ability to bind some pro-inflammatory molecules, complement components and endogenous "danger" signals. The improved survival in endotoxemia was associated with serum levels of pro-inflammatory cytokines, diminished complement consumption and normalization of the coagulation time. We suggest that intravenous immunoglobulin preparations with additionally enhanced polyspecificity have a clinical potential in sepsis and related systemic inflammatory syndromes.

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In the current study it is investigated whether peripheral vision can be used to monitor multi-ple moving objects and to detect single-target changes. For this purpose, in Experiment 1, a modified MOT setup with a large projection and a constant-position centroid phase had to be checked first. Classical findings regarding the use of a virtual centroid to track multiple ob-jects and the dependency of tracking accuracy on target speed could be successfully replicat-ed. Thereafter, the main experimental variations regarding the manipulation of to-be-detected target changes could be introduced in Experiment 2. In addition to a button press used for the detection task, gaze behavior was assessed using an integrated eye-tracking system. The anal-ysis of saccadic reaction times in relation to the motor response shows that peripheral vision is naturally used to detect motion and form changes in MOT because the saccade to the target occurred after target-change offset. Furthermore, for changes of comparable task difficulties, motion changes are detected better by peripheral vision than form changes. Findings indicate that capabilities of the visual system (e.g., visual acuity) affect change detection rates and that covert-attention processes may be affected by vision-related aspects like spatial uncertainty. Moreover, it is argued that a centroid-MOT strategy might reduce the amount of saccade-related costs and that eye-tracking seems to be generally valuable to test predictions derived from theories on MOT. Finally, implications for testing covert attention in applied settings are proposed.

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The second European Zebrafish Principal Investigator (PI) Meeting was held in March, 2012, in Karlsruhe, Germany. It brought together PIs from all over Europe who work with fish models such as zebrafish and medaka to discuss their latest results, as well as to resolve strategic issues faced by this research community. Scientific discussion ranged from the development of new technologies for working with fish models to progress in various fields of research such as injury and repair, disease models, and cell polarity and dynamics. This meeting also marked the establishment of the European Zebrafish Resource Centre (EZRC) at Karlsruhe that in the future will serve as an important focus and community resource for zebrafish- and medaka-based research.