Auf der Suche nach dem optimalen Material : Möglichkeiten und Grenzen der Knochenheilung

Operative Maßnahmen zur Behandlung von knöchernen Defekten müssen bei der Versorgung von Unfallverletzten, aber auch nach der Entfernung von Knochentumoren und -zysten tagtäglich in der Unfallchirurgie durchgeführt werden. Überschreitet das Ausmaß der Defekte eine kritische Größe, kann der Körper diesen Substanzverlust nicht mehr aus eigener Kraft regenerieren, was die statischen und dynamischen Skelettfunktionen beträchtlich einschränkt. Dies ist für die betroffenen Patienten mit weitreichenden Einbußen an Lebensqualität verknüpft. Daher ist es klinisch notwendig, knöcherne Substanzverluste ab einer bestimmten Größe mit einem Material zu ersetzen, das die körpereigenen Regenerationsmechanismen unterstützt, damit letztendlich die ursprüngliche Skelettarchitektur wiederhergestellt wird. Die Überprüfung der Gewebeverträglichkeit von neu entwickelten Knochenersatzmaterialien und die Charakterisierung der Mechanismen, die für ihren Abbau im Körper verantwortlich sind, bilden einen Forschungsschwerpunkt in der Experimentellen Unfallchirurgie der Universität Gießen

Auf der Suche nach dem optimalen Material : Möglichkeiten und Grenzen der Knochenheilung

Operative Maßnahmen zur Behandlung von knöchernen Defekten müssen bei der Versorgung von Unfallverletzten, aber auch nach der Entfernung von Knochentumoren und -zysten tagtäglich in der Unfallchirurgie durchgeführt werden. Überschreitet das Ausmaß der Defekte eine kritische Größe, kann der Körper diesen Substanzverlust nicht mehr aus eigener Kraft regenerieren, was die statischen und dynamischen Skelettfunktionen beträchtlich einschränkt. Dies ist für die betroffenen Patienten mit weitreichenden Einbußen an Lebensqualität verknüpft. Daher ist es klinisch notwendig, knöcherne Substanzverluste ab einer bestimmten Größe mit einem Material zu ersetzen, das die körpereigenen Regenerationsmechanismen unterstützt, damit letztendlich die ursprüngliche Skelettarchitektur wiederhergestellt wird. Die Überprüfung der Gewebeverträglichkeit von neu entwickelten Knochenersatzmaterialien und die Charakterisierung der Mechanismen, die für ihren Abbau im Körper verantwortlich sind, bilden einen Forschungsschwerpunkt in der Experimentellen Unfallchirurgie der Universität Gießen

High predictability of spring phytoplankton biomass in mesocosms at the species, functional group and community level

1. Models aim to predict phytoplankton dynamics based on observed initial conditions and a set of equations and parameters. However, our knowledge about initial conditions in nature is never perfect. Thus, if phytoplankton dynamics are sensitive to small variations in initial conditions, they are difficult to predict. 2. We used time-series data from indoor mesocosm experiments with natural phyto- and zooplankton communities to quantify the extent to which small initial differences in the species, functional group and community biomass in parallel treatments were amplified or buffered over time. We compared the differences in dynamics between replicates and among all mesocosms of 1 year. 3. Temperature-sensitive grazing during the exponential growth phase of phytoplankton caused divergence. In contrast, negative density dependence caused convergence. 4. Mean differences in biomass between replicates were similar for all hierarchical levels. This indicates that differences in their initial conditions were amplified to the same extent. Even though large differences in biomass occasionally occurred between replicates for a short time, dynamics returned to the same path at all hierarchical levels. This suggests that internal feedback mechanisms make the spring development of phytoplankton highly predictable

Prospective Multicenter Randomized Phase III Study of Weekly versus Standard Docetaxel (D2) for First-Line Treatment of Metastatic Breast Cancer

Purpose: Previous phase II studies have indicated a greatly reduced hematotoxicity of docetaxel-based regimens administered on weekly schedules. The present trial was initiated to randomly compare the toxicity and efficacy of weekly docetaxel versus its standard 3-weekly application. Methods: Patients previously untreated with chemotherapy for metastatic disease were recruited. Patients aged >60 years or with a Karnofsky Perfomance Status (KPS) of 60-80% were eligible for the D2 study. Patients were randomized to receive docetaxel either on a 3-weekly {[}75 mg/m(2) every 3 weeks (q3w)] or on a weekly (30 mg/m(2) on days 1, 8, and 15; q4w) schedule. Treatment was continued until a maximum of 8 cycles, unacceptable toxicity, or disease progression. All patients received standard corticosteroid prophylaxis. Results: Since statistical significance for the primary endpoint (toxicity) was achieved in the interim analysis, the study was closed according to the study protocol (102 of 162 patients). Compared to the standard arm, leukopenia >= grade 3 was a rare event in the weekly arm of the D2 study (per-patient analysis: 4.2% q1w vs. 51.9% q3w; p < 0.0001). No difference was observed between the 2 schedules regarding the occurrence of anemia or thrombocytopenia. With regard to non-hematological toxicity, there was a higher incidence of skin/nail and hepatological toxicity with the weekly schedule, whereas neurotoxicity was observed more often in the standard arm. The rate of omitted doses was significantly increased in the weekly arm (8.6% q1w vs. 0% q3w). The overall response rate was 22.9% in the weekly arm compared to 42.6% in the standard arm (p = 0.039). Time to progression was 5.4 (q1w) versus 6.3 (q3w) months (p = 0.91), and overall survival was 22.7 (q1w) versus 15.8 (q3w) months (p = 0.24). Conclusion: The present data support the feasibility of both weekly and 3-weekly application of docetaxel. As expected, severe leukopenia seems avoidable in weekly scheduled single-agent docetaxel and may serve as an important treatment option, particularly in elderly patients and patients with a reduced performance status. Copyright (C) 2011 S. Karger AG, Base

Prospective Multicenter Randomized Phase III Study of Weekly versus Standard Docetaxel plus Doxorubicin (D4) for First-Line Treatment of Metastatic Breast Cancer

Purpose: Previous phase II studies have indicated a greatly reduced hematotoxicity of docetaxel-based regimens administered on weekly schedules. The present trial was initiated to compare the toxicity and efficacy of weekly docetaxel versus its standard 3-weekly application in combination with doxorubicin. Methods: Patients previously untreated with chemotherapy for metastatic disease were recruited. Inclusion criteria were age = grade 3 was observed in the standard arm of the D4 study compared to the weekly schedule (per-patient analysis: 61.9% q3w vs. 65.1% q1w; p > 0.05). Grade 3 and grade 4 fever, diarrhea, and infections occurred more frequently in the standard arm, whereas neurotoxicity and skin/nail disorders were observed more frequently in the weekly arm. Except for fever, none of these differences reached a level of significance. Dose delays, dose reductions, and the rate of omitted doses were increased in the weekly arm. The overall response rate was 44.2% in the weekly arm compared to 52.4% in the standard arm (p = 0.52). Time to progression was 6.2 (q1w) versus 10.3 (q3w) months (p = 0.36), and overall survival was 20.5 (q1w) versus 28.7 (q3w) months (p = 0.98). Conclusion: The present data support the feasibility of both weekly and 3-weekly application of docetaxel in combination with doxorubicin. Nevertheless, given that leukopenia was similar in both arms and the efficacy parameters were at least numerically inferior with the weekly schedule, standard 3-weekly application seems to be preferable for patients requiring combination chemotherapy. Copyright (C) 2011 S. Karger AG, Base

The first decade of oligotrophication of Lake Constance

In Lake Constance, after several decades of cutrophication, a decrease in phosphorus loading over the last decade has lead to a partial recovery from eutrophication. Here we analyse the shift in the taxonomic composition of phytoplankton during the first decade of oligotrophication in Lake Constance. During the 1980s, spring total P concentrations decreased from ca. 130 to less than 50 mgr·l–1. This decrease was reflected by an approximately proportional decrease in summer phytoplankton biomass while spring phytoplankton biomass seemed unresponsive. Major taxonomic changes occured during both growth seasons. In spring, the proportion of diatoms, green algae and Chrysophyta increased while the proportion of Cryptophyta decreased. The summer trend was very different: the relative importance of diatoms decreased and Cryptophyta and Chrysophyta increased, while Chlorophyta reached their peak around 1985. These trends are also analysed at the genus level. Comparison with taxonomic trends during the eutrophication period shows the expected reversals in most cases. Comparison with other lakes shows general similarities, with the notable exception that Planktothrix rubescens has never been important in Lake Constance. The increase of diatoms during spring is attributed to their improved competitive performance with increasing Si:P ratios. Their decrease during summer is explained by the increasing silicate removal from the epilimnion by increasing spring populations

Vitamin D deficiency as a risk factor for dementia: a systematic review and meta-analysis

Abstract Background Sunlight exposure and high vitamin D status have been hypothesised to reduce the risk of developing dementia. The objective of our research was to determine whether lack of sunlight and hypovitaminosis D over time are associated with dementia. Methods We systematically searched MEDLINE (via PubMed), Cochrane Library, EMBASE, SCOPUS, Web of Science, ICONDA, and reference lists of pertinent review articles from 1990 to October 2015. We conducted random effects meta-analyses of published and unpublished data to evaluate the influence of sunlight exposure or vitamin D as a surrogate marker on dementia risk. Results We could not identify a single study investigating the association between sunlight exposure and dementia risk. Six cohort studies provided data on the effect of serum vitamin D concentration on dementia risk. A meta-analysis of five studies showed a higher risk for persons with serious vitamin D deficiency (<25\ua0nmol/L or 7\u201328\ua0nmol/L) compared to persons with sufficient vitamin D supply (\u226550\ua0nmol/L or 54\u2013159\ua0nmol/L) (point estimate 1.54; 95% CI 1.19\u20131.99, I 2 \u2009=\u200920%). The strength of evidence that serious vitamin D deficiency increases the risk of developing dementia, however, is very low due to the observational nature of included studies and their lack of adjustment for residual or important confounders (e.g. ApoE \u3b54 genotype), as well as the indirect relationship between Vitamin D concentrations as a surrogate for sunlight exposure and dementia risk. Conclusions The results of this systematic review show that low vitamin D levels might contribute to the development of dementia. Further research examining the direct and indirect relationship between sunlight exposure and dementia risk is needed. Such research should involve large-scale cohort studies with homogeneous and repeated assessment of vitamin D concentrations or sunlight exposure and dementia outcomes

Taxation of unprocessed sugar or sugar-added foods for reducing their consumption and preventing obesity or other adverse health outcomes:protocol

To assess the effects of taxation of unprocessed sugar or sugar-added foods in the general population on the: consumption of unprocessed sugar or sugar-added foods; prevalence and incidence of overweight and obesity; and prevalence and incidence of diet-related health conditions

Taxation of the fat content of foods for reducing their consumption and preventing obesity or other adverse health outcomes

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effects of taxation of fat content in food on consumption of total fat and saturated fat, energy intake, overweight, obesity, and other adverse health outcomes in the general population

Factors affecting fruit and vegetable consumption and purchase behavior of adults in sub-Saharan Africa:A rapid review

In order to achieve the Sustainable Development Goals, considerable dietary shifts, including an increase in the consumption of fruit and vegetables (FV) will be required. However, worldwide consumption of FV is far below international recommendations, including in many low- and middle-income countries (LMICs), particularly in Africa. Understanding what, where, when, and how people choose to eat requires an understanding of how individuals are influenced by factors in their social, physical, and macro-level environments. In order to develop effective interventions to increase fruit and vegetable consumption, the factors influencing consumer behavior need to be better understood. We conducted a rapid review to assess and synthesize data on individual, social, physical, and macro-level factors that enable or constrain fruit and vegetable consumption and purchase among adults living in sub-Saharan Africa. Our conceptual framework is based on a socio-ecological model which has been adapted to settings in LMICs and Africa. We systematically searched four electronic databases including Scopus, Medline (PubMed), PsycInfo, and African Index Medicus, and screened Google Scholar for gray literature. We included a total of 52 studies and narratively summarized the existing evidence for each identified factor across the different levels. We found that most studies assessed demographic factors at the individual level including household or family income, socio-economic status and education. Furthermore we identified a variety of important factors that influence FV consumption, in the social, physical, and macro environment. These include women's empowerment and gender inequalities, the influence of neighborhood and retail food environment such as distance to market and price of FV as well as the importance of natural landscapes including forest areas for FV consumption. This review identified the need to develop and improve indicators both for exposure and outcome variables but also to diversify research approaches