Putting Cells into Context

Opinion article (excerpt): Cells Live in a Complex World It may sound blatantly obvious, but we have to remind ourselves occasionally that in vivo cells experience an environment with a level of complexity far beyond experimental reach. The developing organism is a highly complex system, where each cell receives a multitude of cues of diverse nature at any given time point. Only the comprehensive integration of all these multivalent interactions determines the actual signaling state and hence the behavior of a cell. The analysis of biological questions is mainly inspired by a reductionist approach adopted from the “exact sciences,” where it has been proven immensely successful. That is, we are used to break down our experimental setup to a manageable number of variables. This of course is inherently contradictory to the complexity of biological systems. While simplification may be the only viable option for the experimenter to dissect biological function down to detail, it has also influenced our perspective toward the experimental systems applied. For example, studies of intracellular signaling pathways are typically performed with cultured cells. Culturing cells in an in vitro setting became a standard model system in biomedical research and with it in cell and developmental biology. These simplified systems allow for the dissection of molecular interactions and pathways and are aimed to deepen and mechanistically understand cellular behavior. While cell cultures have generated a wealth of information into cellular function, the data obtained in vitro frequently are in conflict with in vivo observations. One reason for this discrepancy is that these analyses focus on the cell as a closed functional system, thus conceptually unhinging it from its environment

Possibilities and Limitations of Spatially Explicit Site Index Modelling for Spruce Based on National Forest Inventory Data and Digital Maps of Soil and Climate in Bavaria (SE Germany)

Combining national forest inventory (NFI) data with digital site maps of high resolution enables spatially explicit predictions of site productivity. The aim of this study is to explore the possibilities and limitations of this database to analyze the environmental dependency of height-growth of Norway spruce and to predict site index (SI) on a scale that is relevant for local forest management. The study region is the German federal state of Bavaria. The exploratory methods comprise significance tests and hypervolume-analysis. SI is modeled with a Generalized Additive Model (GAM). In a second step the residuals are modeled using Boosted Regression Trees (BRT). The interaction between temperature regime and water supply strongly determined height growth. At sites with very similar temperature regime and water supply, greater heights were reached if the depth gradient of base saturation was favorable. Statistical model criteria (Double Penalty Selection, AIC) preferred composite variables for water supply and the supply of basic cations. The ability to predict SI on a local scale was limited due to the difficulty to integrate soil variables into the model

Family satisfaction in the intensive care unit: what makes the difference?

Purpose: To assess family satisfaction in the ICU and to identify parameters for improvement. Methods: Multicenter study in Swiss ICUs. Families were given a questionnaire covering overall satisfaction, satisfaction with care and satisfaction with information/decision-making. Demographic, medical and institutional data were gathered from patients, visitors and ICUs. Results: A total of 996 questionnaires from family members were analyzed. Individual questions were assessed, and summary measures (range 0-100) were calculated, with higher scores indicating greater satisfaction. Summary score was 78±14 (mean±SD) for overall satisfaction, 79±14 for care and 77±15 for information/decision-making. In multivariable multilevel linear regression analyses, higher severity of illness was associated with higher satisfaction, while a higher patient:nurse ratio and written admission/discharge criteria were associated with lower overall satisfaction. Using performance-importance plots, items with high impact on overall satisfaction but low satisfaction were identified. They included: emotional support, providing understandable, complete, consistent information and coordination of care. Conclusions: Overall, proxies were satisfied with care and with information/decision-making. Still, several factors, such as emotional support, coordination of care and communication, are associated with poor satisfaction, suggesting the need for improvemen

Papillon-Lefèvre syndrome and squamous cell carcinoma: a case report

Papillon-Lefèvre syndrome is a rare autosomal recessive genodermatosis characterised by palmoplantar hyperkeratosis and severe early-onset periodontitis. The development of malignant cutaneous neoplasms within the hyperkeratotic lesions of the syndrome is very rare. Here, we report on a 67-year-old German Caucasian male with Papillon-Lefèvre syndrome associated with recurrent squamous cell carcinoma. Treatment is symptomatic and not always satisfactory

Biphasic Synovial Sarcoma of the Extremity: Quadruple Approach of Isolated Limb Perfusion, Surgical Ablation, Adipofascial Perforator Flap and Radiation to Avoid Amputation

Synovial sarcoma is a rare type of soft tissue sarcoma that occurs mostly in young adults, and it is always regarded as a high-grade tumor. Here, we report the case of a 31-year-old German Caucasian male with synovial sarcoma of the wrist who was offered amputation at his local hospital. After referral to our Reference Centre for Soft Tissue Sarcoma, the quadruple approach of isolated limb perfusion, surgical ablation, adipofascial perforator flap and radiation avoided amputation and enabled preservation of good hand function with no evidence of recurrence or metastasis after 1 year

Arbitrary multi-site two-photon excitation in four dimensions

We demonstrate dynamic and arbitrary multisite two-photon excitation in three dimensions using the holographic projection method. Rapid response (fourth dimension) is achieved through high-speed noniterative calculation of the hologram using a video graphics accelerator board. We verify that the projected asymmetric spot configurations have sufficient spatiotemporal photon density for localized two-photon excitation. This system is a significant advance and can be applied to time-resolved photolysis of caged compounds in biological cells and complex neuronal networks, nonlinear microfabrication and volume holographic optical storage.Comment: 10 pages including 4 figure

Variability in outcome and resource use in intensive care units

Objective: To examine variability in outcome and resource use between ICUs. Secondary aims: to assess whether outcome and resource use are related to ICU structure and process, to explore factors associated with efficient resource use. Design and setting: Cohort study, based on the SAPS3 database in 275 ICUs worldwide. Patients: 16,560 adults. Measurements and results: Outcome was defined by standardized mortality rate (SMR). Standardized resource use (SRU) was calculated based on length of stay in the ICU, adjusted for severity of acute illness. Each unit was assigned to one of four groups: "most efficient” (SMR and SRU  median); "overachieving” (low SMR, high SRU), "underachieving” (high SMR, low SRU). Univariate analysis and stepwise logistic regression were used to test for factors separating "most” from "least efficient” units. Overall median SMR was 1.00 (IQR 0.77-1.28) and SRU 1.07 (0.76-1.58). There were 91 "most efficient”, 91 "least efficient”, 47 "overachieving”, and 46 "underachieving” ICUs. Number of physicians, of full-time specialists, and of nurses per bed, clinical rounds, availability of physicians, presence of emergency department, and geographical region were significant in univariate analysis. In multivariate analysis only interprofessional rounds, emergency department, and geographical region entered the model as significant. Conclusions: Despite considerable variability in outcome and resource use only few factors of ICU structure and process were associated with efficient use of ICU. This suggests that other confounding factors play an important rol