In recent decades, the fire regime of the Mediterranean Basin has been disturbed by various factors: climate change; forest management policies; land cover; changed landscape. Size and severity have ...notably increased, which in turn have increased large fires events with >500ha burned (high severity). In spite of Mediterranean ecosystems' high resilience to fire, these changes have implied more vulnerability and reduced natural recovery with irreparable long-term negative effects. Knowledge of the response of ecosystems to increasing severity, mainly in semiarid areas, is still lacking, which is needed to rehabilitate and restore burned areas.
Our approach assessed the resilience concept by focusing on the recovery of ecosystem functions and services, measured as changes in the composition and diversity of plant community vegetation and structure. This will be validated in the long term as a model of ecosystem response. Also, depending on the pre-fire characteristics of vegetation, fire severity and the post-fire management, this approach will lead to tools that can be applied to implement post-fire restoration efforts in order to help decision making in planning activities.
Regarding Mediterranean ecosystems' ability to recover after wildfires, this study concludes that pre-fire communities are resilient in these fire-prone areas, but the window for natural recovery in semiarid areas of Aleppo pine forest in SE Iberian Peninsula varied from 3 to 15 post-fire years. Fire severity was also key for effects on the ecosystem: the vegetation types of areas burned with low and medium severity recovered naturally, while those areas with a high-severity burn induced shrublands. We concluded that very strong regeneration activity exists in the short term, and that the negative effects of medium- and high-severity fire are evidenced in the mid and long term, which affect natural recovery. Adaptive forest management to rehabilitate and restore burned Mediterranean ecosystems should be implemented.
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•We assessed resilience of Aleppo pine forests in Eastern Mediterranean Basin•Recovery of ecosystem was monitored in short, medium and long-term after wildfires.•Natural recovery was found in areas burned with low and medium severity.•Areas burned with high severity of fire changed to shrublands.•Fire severity influenced the recovery time of Aleppo pine forest.
Articular cartilage is a load-bearing tissue that lines the surface of bones in diarthrodial joints. Unfortunately, this avascular tissue has a limited capacity for intrinsic repair. Treatment ...options for articular cartilage defects include microfracture and arthroplasty; however, these strategies fail to generate tissue that adequately restores damaged cartilage. Limitations of current treatments for cartilage defects have prompted the field of cartilage tissue engineering, which seeks to integrate engineering and biological principles to promote the growth of new cartilage to replace damaged tissue. To date, a wide range of scaffolds and cell sources have emerged with a focus on recapitulating the microenvironments present during development or in adult tissue, in order to induce the formation of cartilaginous constructs with biochemical and mechanical properties of native tissue. Hydrogels have emerged as a promising scaffold due to the wide range of possible properties and the ability to entrap cells within the material. Towards improving cartilage repair, hydrogel design has advanced in recent years to improve their utility. Some of these advances include the development of improved network crosslinking (e.g. double-networks), new techniques to process hydrogels (e.g. 3D printing) and better incorporation of biological signals (e.g. controlled release). This review summarises these innovative approaches to engineer hydrogels towards cartilage repair, with an eye towards eventual clinical translation.
Conformational changes coupled to ligand binding constitute the structural and energetics basis underlying cooperativity, allostery and, in general, protein regulation. These conformational ...rearrangements are associated with heat capacity changes. ITC is a unique technique for studying binding interactions because of the simultaneous determination of the binding affinity and enthalpy, and for providing the best estimates of binding heat capacity changes.
Still controversial issues in ligand binding are the discrimination between the “conformational selection model” and the “induced fit model”, and whether or not conformational changes lead to temperature dependent apparent binding heat capacities. The assessment of conformational changes associated with ligand binding by ITC is discussed. In addition, the “conformational selection” and “induced fit” models are reconciled, and discussed within the context of intrinsically (partially) unstructured proteins.
Conformational equilibrium is a major contribution to binding heat capacity changes. A simple model may explain both conformational selection and induced fit scenarios. A temperature-independent binding heat capacity does not necessarily indicate absence of conformational changes upon ligand binding. ITC provides information on the energetics of conformational changes associated with ligand binding (and other possible additional coupled equilibria).
Preferential ligand binding to certain protein states leads to an equilibrium shift that is reflected in the coupling between ligand binding and additional equilibria. This represents the structural/energetic basis of the widespread dependence of ligand binding parameters on temperature, as well as pH, ionic strength and the concentration of other chemical species. This article is part of a Special Issue entitled Microcalorimetry in the BioSciences — Principles and Applications, edited by Fadi Bou-Abdallah.
•Ligand-induced conformational changes constitute the structural and energetics basis for protein regulation.•Conformational equilibrium is a major contribution to binding heat capacity changes.•ITC provides the best estimates of binding heat capacity changes.•ITC provides information on the energetics of equilibria coupled to ligand binding, in particular conformational equilibrium.•Conformational selection and induced fit model can be reconciled within the context of a general model.
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The fibulins are a family of secreted glycoproteins associated with basement membranes, elastic fibers, and other matrices. They are expressed in a variety of tissues. Association with these matrix ...structures is mediated by their ability to interact with many extracellular matrix constituents. The seven members of the family are defined by the presence of two structural modules, a tandem repeat of epidermal growth factor-like modules and a unique C-terminal fibulin-type module. They act not only as intermolecular bridges within the extracellular matrix to form supramolecular structures, but also as mediators for cellular processes and tissue remodeling. These important functions of fibulins in a wide range of biological processes have been shown in
in vitro
systems, gene knockout mice, and human genetic disorders. In this review, we describe the structure and function of these proteins and discuss the implication of fibulins in development and diseases.
Occupational respiratory allergy in peach crop workers Pérez‐Calderón, R.; Gonzalo‐Garijo, M. Á.; Rodríguez‐Velasco, F. J. ...
Allergy (Copenhagen),
October 2017, 2017-Oct, 2017-10-00, 20171001, Letnik:
72, Številka:
10
Journal Article
Recenzirano
Background
Occupational respiratory diseases in workers of peach tree crops have been reported punctually and have been associated with sensitization to proteins present in both pollen and leaf tree. ...We report the study of 37 workers with respiratory symptoms related to occupational exposure to peach trees.
Methods
Prick tests and specific IgE determinations were performed with extracts from leaves and branches of peach tree. Immunodetection in leaf extract was realized by sodium dodecyl sulfate–polyacrylamide gel electrophoresis SDS‐PAGE‐immunoblotting with patient sera and rabbit serum anti‐Pru p 3. Immunodetection inhibition was performed with rPru p 3 and pollen profilins. The clinical relevance of sensitization was demonstrated by specific bronchial challenge test (SBCT) with peach leaf extract.
Results
Most patients suffered symptoms when peach trees had leaves, specifically during thinning and harvesting fruit (rhinoconjunctivitis: 100% and asthma: 67.5%). Sensitization to leaf extract was demonstrated in 86% of patients. IgE‐immunoblotting with peach leaf extract revealed in six patient sera a pair of bands of 10 and 16 kDa, and in nine a 16‐kDa band. Those bands could be two isoforms of peach leaf lipid transfer proteins( LTP), so the recognition frequency of some LTP isoform by our patient sera was 42%. 33% of the sera recognized a doubled band of about 14.5 kDa and this recognition was inhibited by nPho d 2. The SBCT with peach leaf extract was positive in the asthmatic sensitized patients tested.
Conclusions
Sensitization to peach leaves was the cause of occupational respiratory symptoms in our patients. Some patient sera revealed IgE‐binding proteins matching LTP and/or profilin.
We have previously shown that a single application of the growth factors ciliary neurotrophic factor (CNTF) or fibroblast growth factor 2 (FGF-2) to the crushed optic nerve of the frog, Rana pipiens, ...increases the numbers and elongation rate of regenerating retinal ganglion cell axons. Here we investigate the effects of these factors on the numbers and types of macrophages that invade the regeneration zone. In control PBS-treated nerves, many macrophages are present 100 μm distal to the crush site at 1 week after injury; their numbers halve by 2 weeks. A single application of CNTF at the time of injury triples the numbers of macrophages at 1 week, with this increase compared to control being maintained at 2 weeks. Application of FGF-2 is equally effective at 1 week, but the macrophage numbers have fallen to control levels at 2 weeks. Immunostaining with a pan-macrophage marker, ED1, and a marker for M2-like macrophages, Arg-1, showed that the proportion of the putative M2 phenotype remained at approximately 80% with all treatments. Electron microscopy of the macrophages at 1 week shows strong phagocytic activity with all treatments, with many vacuoles containing axon fragments and membrane debris. At 2 weeks with PBS or FGF-2 treatment the remaining macrophages are less phagocytically active, containing mainly lipid inclusions. With CNTF treatment, at 2 weeks many of the more numerous macrophages are still phagocytosing axonal debris, although they also contain lipid inclusions. We conclude that the increase in macrophage influx seen after growth factor application is beneficial for the regenerating axons, probably due to more extensive removal of degenerating distal axons, but also perhaps to secretion of growth-promoting substances.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Overhauser effects in insulating solids Can, T V; Caporini, M A; Mentink-Vigier, F ...
The Journal of chemical physics,
08/2014, Letnik:
141, Številka:
6
Journal Article
Recenzirano
Odprti dostop
We report magic angle spinning, dynamic nuclear polarization (DNP) experiments at magnetic fields of 9.4 T, 14.1 T, and 18.8 T using the narrow line polarizing agents 1,3-bisdiphenylene-2-phenylallyl ...(BDPA) dispersed in polystyrene, and sulfonated-BDPA (SA-BDPA) and trityl OX063 in glassy glycerol/water matrices. The (1)H DNP enhancement field profiles of the BDPA radicals exhibit a significant DNP Overhauser effect (OE) as well as a solid effect (SE) despite the fact that these samples are insulating solids. In contrast, trityl exhibits only a SE enhancement. Data suggest that the appearance of the OE is due to rather strong electron-nuclear hyperfine couplings present in BDPA and SA-BDPA, which are absent in trityl and perdeuterated BDPA (d21-BDPA). In addition, and in contrast to other DNP mechanisms such as the solid effect or cross effect, the experimental data suggest that the OE in non-conducting solids scales favorably with magnetic field, increasing in magnitude in going from 5 T, to 9.4 T, to 14.1 T, and to 18.8 T. Simulations using a model two spin system consisting of an electron hyperfine coupled to a (1)H reproduce the essential features of the field profiles and indicate that the OE in these samples originates from the zero and double quantum cross relaxation induced by fluctuating hyperfine interactions between the intramolecular delocalized unpaired electrons and their neighboring nuclei, and that the size of these hyperfine couplings is crucial to the magnitude of the enhancements. Microwave power dependent studies show that the OE saturates at considerably lower power levels than the solid effect in the same samples. Our results provide new insights into the mechanism of the Overhauser effect, and also provide a new approach to perform DNP experiments in chemical, biophysical, and physical systems at high magnetic fields.
Functional foods targeting the improvement of gastrointestinal health are widely recognized; of these, dairy‐based probiotics are the most popular. Thus, the design of nondairy probiotics applying ...fruits, vegetables and cereals has raised great interest in the healthy food sector. The objective of this work was to assess the potential of germinated and malted oat substrates to support the growth of the probiotic cultures Lactobacillus acidophilus, Lactobacillus casei and Lactobacillus rhamnosus. Fermentations were carried out with distinctive oat substrates at inoculum levels of 3, 5 and 7% v/v, substrate concentrations of 3, 5 and 7% w/v and with sucrose addition 1·5% w/v. Lag phase profiles, maximum growth rates and maximal growths were evaluated; protein and sugar contents were also quantified. There was no significant effect (P > 0·05) of the inoculum size on the fermentation kinetics; however, oat media significantly affected the growth kinetics. In simple oat media, Lact. acidophilus exhibited biphasic growth patterns. Lactobacillus growth patterns were significantly affected (P < 0·05) by the supplementation with protein sources. The germination and malting processes significantly improved oats nutrient characteristics demonstrating to be adequate substrates for the fermentation with probiotic lactobacilli. SIGNIFICANCE AND IMPACT OF THE STUDY: In this work, the effect of oat media composition and fermentation conditions on the growth kinetics of three probiotic lactobacilli was determined. The variation in the inoculum levels did not have a significant effect on the probiotic cultures growth. Results revealed that protein supplemented simple, germinated and malted oat enhanced the cell viability of the probiotic lactobacilli; Lactobacillus casei exhibited better growth adaptability. The results also highlight that different weight in volume oat substrate concentrations has particular effects on Lact. casei growth kinetics. Our results contribute to a better understanding of oat‐based media formulations as substrates for probiotic cultures.
Climate change and energy challenges necessitate a deeper understanding of the drivers behind household energy-efficient retrofitting (EER) to inform policy. This study dissects the determinants ...influencing homeowner investments in four EER measures—window double-glazing, insulation of roofs, walls, and floors, solar panel adoption, and heat pump installation—aimed at crafting targeted policy recommendations. We explored the determinants by employing a combination of three methods: a systematic literature review to pinpoint associated factors, principal component analysis to explore Dutch national survey data, and binary logistic regression on the principal components. Our findings indicate a lower propensity for EER adoption among older, long-term homeowners, suggesting the need for governmental financial incentives and technical assistance to bolster energy efficiency in this demographic. Conversely, homeowners engaged in their communities demonstrate a higher likelihood of investing in solar panels and insulation. Policymakers should, therefore, leverage community dynamics to enhance EER uptake, emphasizing information dissemination and collaborative initiatives. Our study underscores the importance of tailored support and the mobilization of community networks as critical to advancing household energy efficiency and broader sustainability goals. These and other insights can also inform energy policies in other countries.
•Neighborhood cohesion positively affects investments in solar panels and insulation.•Encouraging bottom-up initiatives with streamlined regulations is key for EER uptake.•Support for the elderly to adopt EER is crucial.•More focus on retrofitting uptake in multi-family buildings is necessary.
Despite Mediterranean ecosystems' high resilience to fire, both climate and land use change, and alterations in fire regimes increase their vulnerability to fire by affecting the long-term natural ...recovery of ecosystem services. The objective of this work is to study the effects of fire severity on biochemical soil indicators, such as chemical composition or enzymatic activity, related to time after fire and natural vegetation recovery (soil-plant interphase). Soil samples from three wildfires occurring 3, 15 and 21 years ago were taken in the south-eastern Iberian Peninsula (semiarid climate). Sampling included three fire severity levels in naturally regenerated (and changing to shrublands) Pinus halepensis Mill. forests.
In the short-term post-fire period, phosphorus concentration, electrical conductivity and urease activity were positively linked to fire severity, and also influenced β-glucosidade activity in a negative relationship. During the 15–21-year post-fire period, the effects related to medium-high fire severity were negligible and soil quality indicators were linked to natural regeneration success. The results showed that most soil properties recovered in the long term after fire (21 years).
These outcomes will help managers and stakeholders to implement management tools to stabilise soils and to restore burned ecosystems affected by medium-high fire severity. Such knowledge can be considered in adaptive forest management to reduce the negative effects of wildfires and desertification, and to improve the resilience of vulnerable ecosystems in a global change scenario.
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•The plant-soil interphase is related to fire severity and post-fire time.•Fire severity affects ecosystem recovery in the short term.•Plant recovery promotes soil biochemical recovery in the mid term.•Soil properties recover in the long term after fire (21 years).•The plant-soil window for natural recovery in semiarid areas is 15–21 years.
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