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1.
Rheumatology (Oxford) ; 63(2): 446-455, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37216917

RESUMO

OBJECTIVES: Very little is known on the efficacy and safety of drugs for the management of chronic calcium pyrophosphate (CPP) crystal inflammatory arthritis. The objectives of this work were to describe the drugs used in the management of chronic CPP crystal inflammatory arthritis in expert European centres, and to examine treatment retention. METHODS: This was a retrospective cohort study. Charts from patients with a diagnosis of persistent inflammatory and/or recurrent acute CPP crystal arthritis were reviewed in seven European centres. Baseline characteristics were collected, and visits at months 3, 6, 12 and 24 included an assessment of treatment response and safety. RESULTS: One hundred and ninety-four treatments were initiated in 129 patients. Colchicine (used first-line in n = 73/86), methotrexate (used first-line in n = 14/36), anakinra (n = 27) and tocilizumab (n = 25) were the most prescribed treatments, while long-term corticosteroids, hydroxychloroquine, canakinumab and sarilumab were used occasionally. The 24-month on-drug retention was higher for tocilizumab (40%) than anakinra (18.5%) (P < 0.05), while the difference between colchicine (29.1%) and methotrexate (44.4%) was not statistically significant (P = 0.10). Adverse events led to 14.1% of colchicine discontinuations (100% of diarrhoea), 4.3% for methotrexate, 31.8% for anakinra and 20% for tocilizumab; all other discontinuations were related to insufficient response or losses to follow-up. Efficacy outcomes did not differ significantly between treatments throughout follow-up. CONCLUSION: Daily colchicine is the first-line therapy used in chronic CPP crystal inflammatory arthritis, which is considered efficient in a third to half of cases. Second-line treatments include methotrexate and tocilizumab, which have higher retention than anakinra.


Assuntos
Antirreumáticos , Artrite , Produtos Biológicos , Humanos , Antirreumáticos/efeitos adversos , Metotrexato/uso terapêutico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Pirofosfato de Cálcio , Produtos Biológicos/uso terapêutico , Estudos Retrospectivos , Uso Off-Label , Artrite/tratamento farmacológico , Colchicina/efeitos adversos , Resultado do Tratamento
2.
Glob Chang Biol ; 29(16): 4530-4542, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37287121

RESUMO

Non-native trees may have significant impacts on the carbon sink capacity of forested lands. However, large-scale patterns of the relative capacity of native and non-native forests to uptake and store carbon remain poorly described in the literature, and this information is urgently needed to support management decisions. In this study, we analyzed 17,065 plots from the Spanish Forest Inventory (covering c. 30 years) to quantify carbon storage and sequestration of natural forests and plantations of native and non-native trees under contrasting climate types, while controlling for the effects of environmental factors (forest structure, climate, soil, topography, and management). We found that forest origin (non-native vs. native) highly influenced carbon storage and sequestration, but such effect was dependent on climate. Carbon storage was greater in non-native than in native forests in both wet and dry climates. Non-native forests also had greater carbon sequestration than native ones in the wet climate, due to higher carbon gains by tree growth. However, in the dry climate, native forests had greater carbon gains by tree ingrowth and lower carbon loss by tree mortality than non-native ones. Furthermore, forest type (classified by the dominant species) and natural forests versus tree plantations were important determinants of carbon storage and sequestration. Native and non-native Pinus spp. forests had low carbon storage, whereas non-native Eucalyptus spp. forests and native Quercus spp., Fagus sylvatica, and Eurosiberian mixed forests (especially not planted ones) had high carbon storage. Carbon sequestration was greatest in Eucalyptus globulus, Quercus ilex, and Pinus pinaster forests. Overall, our findings suggest that the relative capacity of native and non-native forests to uptake and store carbon depends on climate, and that the superiority of non-native forests over native ones in terms of carbon sequestration declines as the abiotic filters become stronger (i.e., lower water availability and higher climate seasonality).


Assuntos
Pinus , Quercus , Carbono , Florestas , Árvores , Clima , Sequestro de Carbono
3.
Biomacromolecules ; 24(6): 2879-2891, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37249509

RESUMO

The extracellular matrix (ECM) plays an important regulatory role in the development and progression of tumoral tissue. Its functions and properties are crucial in determining tumor cell behavior such as invasion, migration, and malignancy development. Our study explores the role of collagen type I in cancer development and spread using engineered tumor models like multicellular spheroids grown in collagen-based hydrogels to simulate early tumor formation. We employ microfluidic techniques to test the hypothesis that (i) adding Laponite nanoclay to collagen hydrogels modifies mechanical and rheological properties and (ii) changing the stiffness of the collagen microenvironment affects tumor spheroid growth. Our findings support our theories and suggest the use of ECM components and engineered tumor models in cancer research, offering a biocompatible and biomimetic method to tailor the mechanical properties of conventional collagen hydrogels.


Assuntos
Colágeno , Hidrogéis , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Linhagem Celular Tumoral , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Esferoides Celulares/metabolismo , Microambiente Tumoral
4.
J Environ Manage ; 345: 118696, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549639

RESUMO

Invasive alien species have widespread impacts on native biodiversity and ecosystem services. Since the number of introductions worldwide is continuously rising, it is essential to prevent the entry, establishment and spread of new alien species through a systematic examination of future potential threats. Applying a three-step horizon scanning consensus method, we evaluated non-established alien species that could potentially arrive, establish and cause major ecological impact in Spain within the next 10 years. Overall, we identified 47 species with a very high risk (e.g. Oreochromis niloticus, Popillia japonica, Hemidactylus frenatus, Crassula helmsii or Halophila stipulacea), 61 with high risk, 93 with moderate risk, and 732 species with low risk. Many of the species categorized as very high or high risk to Spanish biodiversity are either already present in Europe and neighbouring countries or have a long invasive history elsewhere. This study provides an updated list of potential invasive alien species useful for prioritizing efforts and resources against their introduction. Compared to previous horizon scanning exercises in Spain, the current study screens potential invaders from a wider range of terrestrial, freshwater, and marine organisms, and can serve as a basis for more comprehensive risk analyses to improve management and increase the efficiency of the early warning and rapid response framework for invasive alien species. We also stress the usefulness of measuring agreement and consistency as two different properties of the reliability of expert scores, in order to more easily elaborate consensus ranked lists of potential invasive alien species.


Assuntos
Ecossistema , Espécies Introduzidas , Espanha , Reprodutibilidade dos Testes , Biodiversidade
5.
Plant Cell Environ ; 43(9): 2301-2310, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32542660

RESUMO

Leaf stomatal density is known to co-vary with leaf vein density. However, the functional underpinning of this relation, and how it scales to whole-plant water transport anatomy, is still unresolved. We hypothesized that the balance of water exchange between the vapour phase (in stomata) and liquid phase (in vessels) depends on the consistent scaling between the summed stomatal areas and xylem cross-sectional areas, both at the whole-plant and single-leaf level. This predicted size co-variation should be driven by the co-variation of numbers of stomata and terminal vessels. We examined the relationships of stomatal traits and xylem anatomical traits from the entire plant to individual leaves across seedlings of 53 European woody angiosperm species. There was strong and convergent scaling between total stomatal area and stem xylem area per plant and between leaf total stomatal area and midvein xylem area per leaf across all the species, irrespective of variation in leaf habit, growth-form or relative growth rate. Moreover, strong scaling was found between stomatal number and terminal vessel number, whereas not in their respective average areas. Our findings have broad implications for integrating xylem architecture and stomatal distribution and deepen our understanding of the design rules of plants' water transport network.


Assuntos
Estômatos de Plantas/fisiologia , Plântula/fisiologia , Xilema/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Estômatos de Plantas/anatomia & histologia , Plântula/anatomia & histologia , Plântula/crescimento & desenvolvimento , Água/metabolismo , Madeira , Xilema/fisiologia
6.
Int J Clin Pract ; 74(10): e13584, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32533907

RESUMO

INTRODUCTION: The presence of iron deficiency (ID) in patients with acute heart failure (AHF) is high. There are few studies on the characteristics of these patients and the safety of ferric carboxymaltose administration (FCM). OBJECTIVE: Study the differences among patients with AHF based on the presence and type of ID as well as the safety of FCM administration in these patients. METHOD: The AHF-ID study is a multicentre, analytical, prospective follow-up cohort including patients admitted to six Spanish hospitals for AHF. ID was defined as serum ferritin <100 µg/L (group A) or ferritin 100-299 µg/L with a TSAT <20% (group B). In cases receiving FCM the appearance of adverse events was analysed. Adjusted Cox regression was used to determine the association with 30-days reattendance for AHF after discharge. RESULTS: A total of 221 patients were recruited; 191 (86.4%) presented ID, 121 (63.4%) group A and 70 (36.6%) group B. There were scarce differences between the groups analysed. No differences were found in 30-days reattendance for AHF. FCM was administered to 158 (71.5%) patients, with 8 (5.1%) presenting adverse events, the most frequent being digestive alterations. Treatment was not discontinued in any case. CONCLUSIONS: There are scarce differences between the presence and the type of ID in patients with AHF. The administration of FCM in patients with ID and AHF is safe.


Assuntos
Anemia Ferropriva/sangue , Anemia Ferropriva/tratamento farmacológico , Compostos Férricos/uso terapêutico , Ferritinas/sangue , Insuficiência Cardíaca/tratamento farmacológico , Maltose/análogos & derivados , Anemia Ferropriva/complicações , Feminino , Compostos Férricos/efeitos adversos , Insuficiência Cardíaca/complicações , Humanos , Masculino , Maltose/efeitos adversos , Maltose/uso terapêutico , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
Bot Rev ; 86(2): 93-118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32836310

RESUMO

Ligustrum lucidum is a highly invasive East Asian tree that successfully colonizes several subtropical and temperate areas around the world. Its invasion capacity results from a widespread human use mostly in urban and periurban settings, very abundant fruit and seed production, small bird-dispersed fruits, high germination rates, resprouting capacity, fast growth rates, low herbivory levels and tolerance to a wide range of light, temperature and soil. All these traits contribute to its ability to rapidly increase in abundance, alter biodiversity, landscape ecology and limit its management. This paper reviews the current knowledge on L. lucidum with particular focus on its uses, distribution, invasiveness, ecological and economic impacts and control measures. Most relevant aspect of the review highlight the negative ecological impacts of L. lucidum, its potential to continue expanding its range of distribution and the need of further studies on the eco-physiology of the species, economic impact and social perception of its invasion and early warning systems.

8.
New Phytol ; 222(4): 1873-1882, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30742715

RESUMO

Xylem conduit diameter (Dmax ) of woody angiosperm adults scales with plant size and widens from the stem apex downwards. We hypothesized that, notwithstanding relative growth rate (RGR), growth form or leaf habit, woody seedling conduit Dmax scales linearly with plant size across species; this scaling should be applicable to all vegetative organs, with consistent conduit widening from leaf via stem to main root and coupling with whole-leaf area and whole-stem xylem area. To test these hypotheses, organ-specific xylem anatomy traits and size-related traits in laboratory-grown seedlings were analyzed across 55 woody European species from cool-temperate and Mediterranean climates. As hypothesized, conduit Dmax of each organ showed similar scaling with plant size and consistent basipetal widening from the leaf midvein via the stem to the main root across species, independently of growth form, RGR and leaf habit. We also found a strong correlation between Dmax and average leaf area, and between stem xylem area and whole-plant leaf area. We conclude that seedlings of ecologically wide-ranging woody species converge in their allometric scaling of conduit diameters within and across plant organs. These relationships will contribute to modeling of water transport in woody vegetation that accounts for the whole life history from the trees' regeneration phase to adulthood.


Assuntos
Plântula/fisiologia , Madeira/fisiologia , Xilema/fisiologia , Folhas de Planta/fisiologia , Caules de Planta/fisiologia , Análise de Regressão
9.
Environ Manage ; 59(5): 856-869, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28110358

RESUMO

The water demand for human activities is rapidly increasing in developing countries. Under these circumstances, preserving aquatic ecosystems should be a priority which requires the development of quality criteria. In this study we perform a preliminary prioritization of the risky substances based on reported ecotoxicological studies and guidelines for the Biobío watershed (Central Chile). Our specific aims are (1) reviewing the scientific information on the aquatic pollution of this watershed, (2) determining the presence and concentration of potential toxic substances in water, sediment and effluents, (3) searching for quality criteria developed by other countries for the selected substances and (4) prioritizing the most risky substances by means of deterministic ecotoxicological risk assessment. We found that paper and mill industries were the main sources of point pollution, while forestry and agriculture were mostly responsible for non-point pollution. The most risky organic substances in the water column were pentachlorophenol and heptachlor, while the most relevant inorganic ones were aluminum, copper, unionized ammonia and mercury. The most risky organic and inorganic substances in the sediment were phenanthrene and mercury, respectively. Our review highlights that an important effort has been done to monitor pollution in the Biobío watershed. However there are emerging pollutants and banned compounds-especially in sediments-that require to be monitored. We suggest that site-specific water quality criteria and sediment quality criteria should be developed for the Biobío watershed, considering the toxicity of mixtures of chemicals to endemic species, and the high natural background level of aluminum in the Biobío.


Assuntos
Monitoramento Ambiental/métodos , Rios/química , Poluentes Químicos da Água/análise , Agricultura , Alumínio/análise , Amônia/análise , Chile , Cobre/análise , Agricultura Florestal , Sedimentos Geológicos/análise , Heptacloro/análise , Mercúrio/análise , Papel , Pentaclorofenol/análise , Fenantrenos/análise , Qualidade da Água
10.
Eur J Cell Biol ; 103(2): 151396, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38359522

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive lethal malignancy that accounts for more than 90% of pancreatic cancer diagnoses. Our research is focused on the physico-chemical properties of the tumour microenvironment (TME), including its tumoural extracellular matrix (tECM), as they may have an important impact on the success of cancer therapies. PDAC xenografts and their decellularized tECM offer a great material source for research in terms of biomimicry with the original human tumour. Our aim was to evaluate and quantify the physico-chemical properties of the PDAC TME. Both cellularized (native TME) and decellularized (tECM) patient-derived PDAC xenografts were analyzed. A factorial design of experiments identified an optimal combination of factors for effective xenograft decellularization. Our results provide a complete advance in our understanding of the PDAC TME and its corresponding stroma, showing that it presents an interconnected porous architecture with very low permeability and small pores due to the contractility of the cellular components. This fact provides a potential therapeutic strategy based on the therapeutic agent size.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Microambiente Tumoral , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Humanos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Animais , Camundongos , Matriz Extracelular/metabolismo
11.
J Biomed Mater Res A ; 111(1): 88-105, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36205241

RESUMO

Mesenchymal stem cells have contributed to the continuous progress of tissue engineering and regenerative medicine. Adipose-derived stem cells (ADSC) possess many advantages compared to other origins including easy tissue harvesting, self-renewal potential, and fast population doubling time. As multipotent cells, they can differentiate into osteoblastic cell linages. In vitro bone models are needed to carry out an initial safety assessment in the study of novel bone regeneration therapies. We hypothesized that 3D bone-on-a-chip models containing ADSC could closely recreate the physiological bone microenvironment and promote differentiation. They represent an intermedium step between traditional 2D-in vitro and in vivo experiments facilitating the screening of therapeutic molecules while saving resources. Herein, we have differentiated ADSC for 7 and 14 days and used them to fabricate in vitro bone models by embedding the pre-differentiated cells in a 3D collagen matrix placed in a microfluidic chip. Osteogenic markers such as alkaline phosphatase activity, calcium mineralization, changes on cell morphology, and expression of specific proteins (bone sialoprotein 2, dentin matrix acidic phosphoprotein-1, and osteocalcin) were evaluated to determine cell differentiation potential and evolution. This is the first miniaturized 3D-in vitro bone model created from pre-differentiated ADSC embedded in a hydrogel collagen matrix which could be used for personalized bone tissue engineering.


Assuntos
Hidrogéis , Engenharia Tecidual , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Dispositivos Lab-On-A-Chip , Células Cultivadas , Diferenciação Celular , Osteogênese , Células-Tronco , Tecido Adiposo , Colágeno/metabolismo
12.
Sci Total Environ ; 877: 162961, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36958556

RESUMO

Humans have introduced non-native trees (NNT) all over the world to take advantage of the plethora of benefits they provide. However, depending on the context, NNT may present a diverse range of effects on ecosystem services (ES), from benefits to drawbacks, which may hinder the development of policies for these species. Unfortunately, the attempts so far to understand the impacts of NNT on ES only explained a low proportion of their variation. Here we analyze the variation in impacts of NNT on regulating ecosystem services (RES) by using a global database, which covers the effect size of multiple NNT species on six RES (climate regulation, soil erosion regulation, soil fertility, soil formation, hydrological cycle regulation, and fire protection). We used a wide range of predictors to account for the context-dependency of impacts distributed in five groups: the RES type, functional traits of both the NNT and the dominant NT of the recipient ecosystem, phylogenetic and functional distances between NNT and NT, climatic context, and human population characteristics. Using boosted regression trees and regression trees, we found that the most influential predictors of NNT impacts on RES were annual mean temperatures and precipitation seasonality, followed by the type of RES, human population density, and NNT height. In regions with warm temperatures and low seasonality, NNT tended to increase RES. NNT impacts were greater in densely populated regions. Smaller NNT exerted greater positive impacts on climate regulation and soil erosion regulation in tropical regions than in other climates. We highlight that benign climates and high population density exacerbate the effects of NNT on RES, and that soil fertility is the most consistently affected RES. Knowledge of the factors that modulate NNT impacts can help to predict their potential effects on RES in different parts of the world and at various environmental settings.


Assuntos
Ecossistema , Solo , Humanos , Filogenia , Temperatura
13.
Gels ; 9(6)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37367175

RESUMO

Innovative materials are needed to produce scaffolds for various tissue engineering and regenerative medicine (TERM) applications, including tissue models. Materials derived from natural sources that offer low production costs, easy availability, and high bioactivity are highly preferred. Chicken egg white (EW) is an overlooked protein-based material. Whilst its combination with the biopolymer gelatin has been investigated in the food technology industry, mixed hydrocolloids of EW and gelatin have not been reported in TERM. This paper investigates these hydrocolloids as a suitable platform for hydrogel-based tissue engineering, including 2D coating films, miniaturized 3D hydrogels in microfluidic devices, and 3D hydrogel scaffolds. Rheological assessment of the hydrocolloid solutions suggested that temperature and EW concentration can be used to fine-tune the viscosity of the ensuing gels. Fabricated thin 2D hydrocolloid films presented globular nano-topography and in vitro cell work showed that the mixed hydrocolloids had increased cell growth compared with EW films. Results showed that hydrocolloids of EW and gelatin can be used for creating a 3D hydrogel environment for cell studies inside microfluidic devices. Finally, 3D hydrogel scaffolds were fabricated by sequential temperature-dependent gelation followed by chemical cross-linking of the polymeric network of the hydrogel for added mechanical strength and stability. These 3D hydrogel scaffolds displayed pores, lamellae, globular nano-topography, tunable mechanical properties, high affinity for water, and cell proliferation and penetration properties. In conclusion, the large range of properties and characteristics of these materials provide a strong potential for a large variety of TERM applications, including cancer models, organoid growth, compatibility with bioprinting, or implantable devices.

14.
New Phytol ; 195(4): 912-922, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22709277

RESUMO

Functional traits, their plasticity and their integration in a phenotype have profound impacts on plant performance. We developed structural equation models (SEMs) to evaluate their relative contribution to promote invasiveness in plants along resource gradients. We compared 20 invasive-native phylogenetically and ecologically related pairs. SEMs included one morphological (root-to-shoot ratio (R/S)) and one physiological (photosynthesis nitrogen-use efficiency (PNUE)) trait, their plasticities in response to nutrient and light variation, and phenotypic integration among 31 traits. Additionally, these components were related to two fitness estimators, biomass and survival. The relative contributions of traits, plasticity and integration were similar in invasive and native species. Trait means were more important than plasticity and integration for fitness. Invasive species showed higher fitness than natives because: they had lower R/S and higher PNUE values across gradients; their higher PNUE plasticity positively influenced biomass and thus survival; and they offset more the cases where plasticity and integration had a negative direct effect on fitness. Our results suggest that invasiveness is promoted by higher values in the fitness hierarchy--trait means are more important than trait plasticity, and plasticity is similar to integration--rather than by a specific combination of the three components of the functional strategy.


Assuntos
Espécies Introduzidas , Característica Quantitativa Herdável , Aptidão Genética , Modelos Biológicos , Análise Multivariada , Fenótipo , Fotossíntese/fisiologia , Filogenia , Desenvolvimento Vegetal
15.
Plant Cell Environ ; 35(5): 839-56, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22070625

RESUMO

Finite mesophyll diffusion conductance (g(m) ) significantly constrains net assimilation rate (A(n) ), but g(m) variations and variation sources in response to environmental stresses during leaf development are imperfectly known. The combined effects of light and water limitations on g(m) and diffusion limitations of photosynthesis were studied in saplings of Populus tremula L. An one-dimensional diffusion model was used to gain insight into the importance of key anatomical traits in determining g(m) . Leaf development was associated with increases in dry mass per unit area, thickness, density, exposed mesophyll (S(mes) /S) and chloroplast (S(c) /S) to leaf area ratio, internal air space (f(ias) ), cell wall thickness and chloroplast dimensions. Development of S(mes) /S and S(c) /S was delayed under low light. Reduction in light availability was associated with lower S(c) /S, but with larger f(ias) and chloroplast thickness. Water stress reduced S(c) /S and increased cell wall thickness under high light. In all treatments, g(m) and A(n) increased and CO(2) drawdown because of g(m) , C(i) -C(c) , decreased with increasing leaf age. Low light and drought resulted in reduced g(m) and A(n) and increased C(i) -C(c) . These results emphasize the importance of g(m) and its components in determining A(n) variations during leaf development and in response to stress.


Assuntos
Luz , Fotossíntese/fisiologia , Transpiração Vegetal/fisiologia , Populus/fisiologia , Estresse Fisiológico/fisiologia , Água/metabolismo , Dióxido de Carbono/metabolismo , Parede Celular/metabolismo , Cloroplastos/metabolismo , Desidratação , Difusão , Células do Mesofilo/metabolismo , Modelos Biológicos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Folhas de Planta/ultraestrutura , Estômatos de Plantas/fisiologia , Populus/crescimento & desenvolvimento , Populus/efeitos da radiação , Populus/ultraestrutura , Fatores de Tempo
16.
Materials (Basel) ; 15(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35407903

RESUMO

Creating biofunctional artificial scaffolds could potentially meet the demand of patients suffering from bone defects without having to rely on donors or autologous transplantation. Three-dimensional (3D) printing has emerged as a promising tool to fabricate, by computer design, biodegradable polymeric scaffolds with high precision and accuracy, using patient-specific anatomical data. Achieving controlled degradation profiles of 3D printed polymeric scaffolds is an essential feature to consider to match them with the tissue regeneration rate. Thus, achieving a thorough characterization of the biomaterial degradation kinetics in physiological conditions is needed. Here, 50:50 blends made of poly(ε-caprolactone)-Poly(D,L-lactic-co-glycolic acid (PCL-PLGA) were used to fabricate cylindrical scaffolds by 3D printing (⌀ 7 × 2 mm). Their hydrolytic degradation under static and dynamic conditions was characterized and quantified. For this purpose, we designed and in-house fabricated a customized bioreactor. Several techniques were used to characterize the degradation of the parent polymers: X-ray Photoelectron Spectroscopy (XPS), Gel Permeation Chromatography (GPC), Scanning Electron Microscopy (SEM), evaluation of the mechanical properties, weigh loss measurements as well as the monitoring of the degradation media pH. Our results showed that flow perfusion is critical in the degradation process of PCL-PLGA based scaffolds implying an accelerated hydrolysis compared to the ones studied under static conditions, and up to 4 weeks are needed to observe significant degradation in polyester scaffolds of this size and chemical composition. Our degradation study and characterization methodology are relevant for an accurate design and to tailor the physicochemical properties of polyester-based scaffolds for bone tissue engineering.

17.
Mol Biol Rep ; 38(5): 2987-92, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20146006

RESUMO

The Sp1 binding site polymorphism in collagen type I alpha 1 gene (COLIA1) has been associated with osteoporosis (OP) and bone mineral density (BMD). The aim of this study was to explore the association of this polymorphism with OP and BMD in the Mexican population by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) procedure. Allelic and genotypic frequencies from the Sp1 polymorphism were determined in 100 women with OP, 100 women without OP and 500 subjects from general Mexican population (GMP). Distribution of Sp1 polymorphism was in Hardy-Weinberg equilibrium. In spite of population structure due to racial mix in Mexican population, associations with OP were demonstrated. The frequency of "s" allele was significantly higher in women with OP (35%) than in women without OP (11%; P < 0.00001). Interestingly, "ss" genotype, was exclusive of women with OP and was associated with low BMD (0.588 ± 0.077 g/cm(2)) in contrast to "SS" genotype (0.733 ± 0.039 g/cm(2); P = 0.0001). This work confirms the association of Sp1 polymorphism with low BMD and OP in Mexican population and make sure to use Sp1 as a genetic marker for OP in our population.


Assuntos
Sítios de Ligação/genética , Colágeno Tipo I/genética , Vértebras Lombares/patologia , Osteoporose/genética , Polimorfismo Genético , Fator de Transcrição Sp1 , Idoso , Densidade Óssea/genética , Cadeia alfa 1 do Colágeno Tipo I , Feminino , Marcadores Genéticos , Genética Populacional , Humanos , México , Pessoa de Meia-Idade , Osteoporose/patologia
18.
Environ Manage ; 48(4): 764-73, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21842417

RESUMO

The exotic trees Ailanthus altissima, Robinia pseudoacacia, Acer negundo and Elaeagnus angustifolia coexist with the native trees Fraxinus angustifolia and Ulmus minor in river banks of central Spain. Similarly, the exotic trees Acacia dealbata and Eucalyptus globulus co-occur with the natives Quercus pyrenaica and Pinus pinaster in Northwest Spain. We aimed to identify the environmental conditions that favour or hamper the establishment success of these species. In spring 2008, seeds of the studied species were sown under an experimental gradient of light (100, 65, 35, 7% of full sunlight) combined with three levels of soil moisture (mean soil water potential = -0.97, -1.52 and -1.77 MPa.). During the first growing season we monitored seed emergence and seedling survival. We found that the effect of light on the establishment success was stronger than the effect of soil moisture. Both exotic and native species of central Spain showed a good performance under high light, A. negundo being the most shade tolerant. Water shortage diminished E. angustifolia and A. altissima success. Among NW Spain species, A. dealbata and P. pinaster were found to be potential competitors for colonizing high-irradiance scenarios, while Q. pyrenaica and E. globulus were more successful under moderate shade. High soil moisture favoured E. globulus but not A. dealbata establishment. These results contribute to understand some of the factors controlling for spatial segregation between coexisting native and exotic tree species, and can help to take decisions orientated to the control and management of these exotic species.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Árvores/crescimento & desenvolvimento , Análise de Variância , Solo/análise , Espanha , Especificidade da Espécie , Luz Solar , Temperatura , Água
19.
Sci Total Environ ; 778: 146141, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33711596

RESUMO

Tree taxa are often planted beyond their native range to increase the provision of some ecosystem services. Yet, they can disrupt ecosystem processes in their new ranges, causing changes in the provision of other services. Here we review the effects of five widespread tree taxa (Acacia, Ailanthus, Eucalyptus, Pinus and Robinia) on six regulating ecosystem services in areas where they are non-native. We conducted a literature search for pair-wise comparisons between sites dominated by any of the selected taxa and sites with native vegetation. An array of variables were used as indicators for each ecosystem service. Data were analysed using multi-level meta-analyses to compare effects of taxa on each ecosystem service, and effects of the same taxa across contexts. We compiled 857 case studies from 107 source papers. Several taxa tended to increase climate regulation, mostly Eucalyptus. Acacia decreased fire risk prevention. Robinia, Acacia and Ailanthus increased soil fertility, while Eucalyptus and Pinus, tended to decrease it. Soil formation was enhanced by Robinia and Ailanthus. Acacia promoted the increase of water in land pools, while Eucalyptus tended to decrease them. All effects show a large heterogeneity across case studies. Part of this heterogeneity could be attributed to gross climatic differences (i.e. biome), to species differences within each genus, to the structure of the recipient ecosystem, and/or to human management. Managers and policy-makers should consider the context-dependency and the potential effects of non-native trees on a wide range of services to ground their decisions. Our analyses also revealed important gaps of knowledge (e.g. on fire risk prevention, erosion control or water cycle regulation) and some potential publication bias. The methodology used here easily allows for future updates as new information will become available.


Assuntos
Eucalyptus , Árvores , Mudança Climática , Ecossistema , Humanos , Solo
20.
Oecologia ; 162(3): 781-90, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20155374

RESUMO

Leaf traits related to the performance of invasive alien species can influence nutrient cycling through litter decomposition. However, there is no consensus yet about whether there are consistent differences in functional leaf traits between invasive and native species that also manifest themselves through their "after life" effects on litter decomposition. When addressing this question it is important to avoid confounding effects of other plant traits related to early phylogenetic divergences and to understand the mechanism underlying the observed results to predict which invasive species will exert larger effects on nutrient cycling. We compared initial leaf litter traits, and their effect on decomposability as tested in standardized incubations, in 19 invasive-native pairs of co-familial species from Spain. They included 12 woody and seven herbaceous alien species representative of the Spanish invasive flora. The predictive power of leaf litter decomposition rates followed the order: growth form > family > status (invasive vs. native) > leaf type. Within species pairs litter decomposition tended to be slower and more dependent on N and P in invaders than in natives. This difference was likely driven by the higher lignin content of invader leaves. Although our study has the limitation of not representing the natural conditions from each invaded community, it suggests a potential slowing down of the nutrient cycle at ecosystem scale upon invasion.


Assuntos
Plantas/metabolismo , Filogenia , Espanha
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