Slashing may have potential for controlling Phragmites australis in long‐inundated parts of a Ramsar‐listed wetland

Phragmites or Common Reed (Phragmites australis) is a natural component of many wetlands but can be highly invasive. Phragmites is encroaching into important mudflat habitat areas of the Ramsar‐listed Seaford Wetlands (Melbourne, Victoria), which are critical for migratory birds. We assessed the efficacy of slashing as a means of controlling Phragmites by establishing twelve 5 m × 5 m quadrats within mature Phragmites reed beds and slashing half of them. The response of Phragmites to slashing was highly variable and dependent on the elevation (i.e. subsequent flooding) of the slashed quadrats. Phragmites regrowth was minimal in lower‐lying quadrats which were wholly inundated for several months each of the following two years (to a mean depth of ~22 cm). In contrast, in quadrats of higher elevation, which were mostly only partially or shallowly inundated, Phragmites recovered almost completely within 10 months. In quadrats that were not slashed there was no change in Phragmites cover (i.e. it remained ~100%) irrespective of flooding extent. It is suspected that prolonged flooding above the height of the remaining stubble is necessary to prevent recovery. Thus, slashing may be a successful means of controlling Phragmites when low‐lying areas are targeted and these are subsequently flooded to a sufficient depth (e.g. >20 cm) for at least several months.     

An evolutionary trade-off between protein turnover rate and protein aggregation favors a higher aggregation propensity in fast degrading proteins

We previously showed the existence of selective pressure against protein aggregation by the enrichment of aggregation-opposing 'gatekeeper' residues at strategic places along the sequence of proteins. Here we analyzed the relationship between protein lifetime and protein aggregation by combining experimentally determined turnover rates, expression data, structural data and chaperone interaction data on a set of more than 500 proteins. We find that selective pressure on protein sequences against aggregation is not homogeneous but that short-living proteins on average have a higher aggregation propensity and fewer chaperone interactions than long-living proteins. We also find that short-living proteins are more often associated to deposition diseases. These findings suggest that the efficient degradation of high-turnover proteins is sufficient to preclude aggregation, but also that factors that inhibit proteasomal activity, such as physiological ageing, will primarily affect the aggregation of short-living proteins.     

α-Galactosidase Aggregation Is a Determinant of Pharmacological Chaperone Efficacy on Fabry Disease Mutants

Fabry disease is a lysosomal storage disorder caused by loss of α-galactosidase function. More than 500 Fabry disease mutants have been identified, the majority of which are structurally destabilized. A therapeutic strategy under development for lysosomal storage diseases consists of using pharmacological chaperones to stabilize the structure of the mutant protein, thereby promoting lysosomal delivery over retrograde degradation. The substrate analog 1-deoxygalactonojirimycin (DGJ) has been shown to restore activity of mutant α-galactosidase and is currently in clinical trial for treatment of Fabry disease. However, only ～65% of tested mutants respond to treatment in cultured patient fibroblasts, and the structural underpinnings of DGJ response remain poorly explained. Using computational modeling and cell culture experiments, we show that the DGJ response is negatively affected by protein aggregation of α-galactosidase mutants, revealing a qualitative difference between misfolding-associated and aggregation-associated loss of function. A scoring function combining predicted thermodynamic stability and intrinsic aggregation propensity of mutants captures well their aggregation behavior under overexpression in HeLa cells. Interestingly, the same classifier performs well on DGJ response data of patient-derived cultured lymphoblasts, showing that protein aggregation is an important determinant of chemical chaperone efficiency under endogenous expression levels as well. Our observations reinforce the idea that treatment of aggregation-associated loss of function observed for the more severe α-galactosidase mutants could be enhanced by combining pharmacological chaperone treatment with the suppression of mutant aggregation, e.g. via proteostatic regulator compounds that increase cellular chaperone expression.     

High-resolution CryoFESEM of individual cell adhesion molecules (CAMs) in the glycocalyx of human platelets: detection of P-selectin (CD62P), GPI-IX complex (CD42A/CD42B alpha,B beta), and integrin GPIIbIIIa (CD41/CD61) by immunogold labeling and stereo imaging.

The aim of this study was to develop a model for the detection of individual cell adhesion molecules (CAMs) in the glycocalyx of spread human platelets using high-resolution cryo-field emission scanning electron microscopy (cryoFESEM). Three surface glycoprotein CAMs, P-selectin (CD62P), GPIba in the GPI-IX complex (CD42a/CD42b alpha,b beta), and the integrin GPIIbIIIa (CD41/CD61) in the human platelet were selected on the basis of their unique topographic shape. Spread human platelets were indirectly immunolabeled with 10-nm colloidal gold and then cryoimmobilized. After sublimation of water from the cryoimmobilized sample, partially freeze-dried platelets were coated unidirectionally with Pt, stabilized with carbon, and examined in an in-lens cryoFESEM using high-resolution backscattered electron imaging. CAMs were detected by indirect immunogold labeling and the length of each type of CAM was determined using analysis of differences in parallax as measured in the software program Sterecon. Our results demonstrate the efficacy of using high-resolution cryoFESEM to recognize and detect individual CAMs in the glycocalyx. Further advances in production of metal coatings with finer granularity, together with improvements in imaging (tilting and angle of stereo images), may provide better definition of the topography associated with glycosylation and formation of multimeric CAM complexes. (J Histochem Cytochem 49:809-819, 2001)     

Beleidsaanbevelingen omtrent de implementatie van val- en fractuurpreventie bij thuiswonende ouderen

Several factors impede the implementation of effective strategies for fall and fracture prevention. The Centre of Expertise for Fall & Fracture prevention Flanders organized a symposium, “Implementation of fall en fracture prevention in older people”, with the aim to elaborate on the facilitation of effective strategies for falls and fall-related injuries in community-dwelling older people in Flanders. This article summarizes the main bottlenecks for implementation and provides recommendations for optimizing dissemination and implementation.     

Effect and Process Evaluation of a Cluster Randomized Control Trial on Water Intake and Beverage Consumption in Preschoolers from Six European Countries: The ToyBox-Study

BackgroundWithin the ToyBox-study, a kindergarten-based, family-involved intervention was developed to prevent overweight and obesity in European preschoolers, targeting four key behaviours related to early childhood obesity, including water consumption. The present study aimed to examine the effect of the ToyBox-intervention (cluster randomized controlled trial) on water intake and beverage consumption in European preschoolers and to investigate if the intervention effects differed by implementation score of kindergartens and parents/caregivers.MethodA sample of 4964 preschoolers (4.7±0.4 years; 51.5% boys) from six European countries (Belgium, Bulgaria, Germany, Greece, Poland, Spain) was included in the data analyses. A standardized protocol was used and parents/caregivers filled in socio-demographic data and a food-frequency questionnaire. To assess intervention effects, multilevel repeated measures analyses were conducted for the total sample and for the six country-specific samples. Based on the process evaluation questionnaire of teachers and parents/caregivers, an implementation score was constructed. To assess differences in water intake and beverage consumption by implementation score in the total sample, multilevel repeated measures analyses were performed.ResultsLimited intervention effects on water intake from beverages and overall beverage consumption were found. However, important results were found on prepacked fruit juice consumption, with a larger decrease in the intervention group compared to the control group. However, also a decline in plain milk consumption was found. Implementation scores were rather low in both kindergartens and parents/caregivers. Nevertheless, more favorable effects on beverage choices were found in preschoolers whose parents/caregivers and kindergarten teachers had higher implementation scores compared to those with lower implementation scores.ConclusionThe ToyBox-intervention can provide the basis for the development of more tailor-made interventions. However, new strategies to improve implementation of interventions should be created.     

Health Related Behaviours in Normal Weight and Overweight Preschoolers of a Large Pan-European Sample: The ToyBox-Study

The aim of this study was to investigate the associations of health related behaviours (HRB) with Body Mass Index (BMI) in preschoolers, and to study the likelihood of being overweight/obese in relation to compliance with recommended HRB. The sample consisted of 3301 normal weight and overweight/obese preschoolers (mean age: 4.7 years; 52% boys, 85% normal weight) from six European countries (Belgium, Bulgaria, Germany, Greece, Poland, Spain). Height and weight were measured, total daily step counts were registered during six days, and HRB were assessed with validated parental surveys in 2012. Multiple linear and logistic regression analyses were performed. Only few HRB were significantly associated with BMI. In boys, higher water intake and higher soft drink and higher fruit consumption were significantly associated with higher BMI. Boys drinking less water than recommended were less likely to be overweight/obese (OR = 0.60), while boys who consume soft drinks were more likely to be overweight/obese (OR = 1.52). In girls, higher water intake, higher vegetable consumption, and more TV time on weekend days were significantly associated with higher BMI. Girls eating less vegetables than recommended were less likely to be overweight/obese (OR = 0.62), and girls who engaged in quiet play for more than 90 minutes on weekend days were more likely to be overweight/obese (OR = 1.64). In general, the associations between HRB and BMI or being overweight/obese were limited and mainly related to dietary intake. Awareness campaigns for caregivers should stress that HRB of young children are important and independent of children’s weight status.     

The potential of soil seed banks of a eucalypt wetland forest to aid restoration

Soil seed banks can play an important role in the regeneration of wetland vegetation. However, their potential role in the restoration of degraded wetland forests is less certain. I surveyed the soil seed bank and extant floras of four sites across a eucalypt wetland forest of variable vegetation condition. At each site, the extant vegetation was surveyed within two 5 × 5 m² quadrats, each from which five composite soil seed bank samples were collected. Across the four sites, 57 (including 18 exotic) species were identified in the extant vegetation, while from the seed bank samples 6379 seedlings emerged from 80 taxa, 33 of which were exotic species. The soil seed bank was dominated by native and exotic monocots, and contained very few seeds of wetland tree or shrub species. Overall, the similarity between the extant and seed bank floras was very low (~24 %). Soil seed banks are likely to be of limited use in the restoration of degraded wetland forests, because the dominant species in such systems—woody and clonal plants—are typically absent from the soil seed bank. Wetland soil seed banks may contribute to the maintenance and diversity of understorey vegetation, however, they may also act as a source of exotic plant invasions, particularly when a wetland is degraded.     

Managed flooding can augment the benefits of natural flooding for native wetland vegetation

Managed flooding is increasingly being used to maintain and restore the ecological values of floodplain wetlands. However, evidence for its effectiveness is sometimes inconsistent and water available for environmental purposes often limited. We experimentally inundated a floodplain wetland (or “billabong”) in late spring by pumping water from its adjacent creek, aiming to promote the native wetland flora and suppress terrestrial exotics. Vegetation was surveyed before (spring) and after (late summer) the managed flood in the experimental billabong and in three control billabongs. Floodplain water levels were continuously monitored. Wet conditions caused two of the control billabongs to also flood, but to a lesser extent than the experimental billabong. We therefore assessed vegetation changes relative to flooding duration. With increasing flooding duration, the cover of wetland vegetation (amphibious and aquatic species) increased and the cover of terrestrial and exotic vegetation decreased, with these effects largest in the deliberately flooded billabong. Flooding durations greater than 20 days generally resulted in increased cover of wetland plants and restricted the growth of terrestrial plants. Reinstatement of more appropriate flooding regimes can thus promote native wetland plants, while suppressing terrestrial exotic species. Our study also provides evidence for the use of modest water allocations to augment the benefits of natural flooding in the maintenance and restoration of native wetland plant communities.