In vitro exposure of porcine spermatozoa to methylparaben, and propylparaben, alone or in combination adversely affects sperm quality.

Parabens (PBs) are widely used in the cosmetic, pharmaceutical, and food industries as preservatives of products. Because of its great use, humans and other organisms are highly exposed daily. However, little is known about the effect of PBs on male infertility. Therefore, the aim of the present study was to evaluate the effect of methylparaben (MePB) and propylparaben (PrPB), alone or in combination, on the physiological characteristics of pig in vitro exposed sperm to different concentrations (0, 200, 500, and 700 µM) for viability, motility, and acrosome integrity evaluation and (0, 200, 500, 700, 1000, and 2000 µM) for DNA fragmentation index evaluation, after 4 h of exposure. The results showed that sperm viability decreased after exposure to MePB from the concentration of 500 µM. In the PrPB and mixture groups, viability decreased at all concentrations except for the control. The decrease in viability of sperm exposed to PrPB was greater than that of the mixture and MePB groups. Sperm motility decreased in all the experimental groups exposed to PBs, at all concentrations, except for the control group. Acrosome integrity was not decreased in the MePB group; however, in the PrPB group, it decreased at a concentration of 200 µM and in the mixture at 500 µM. All groups exhibited DNA damage at different concentrations, except for the control group. Additionally, the effect of PBs on sperm quality was concentration-dependent. The results demonstrated that MePB and PrPB alone or in combination can have adverse effects on sperm quality parameters. MePB had lower toxicity than did both PrPB and the mixture. The mixture did not have an additive effect on any of the parameters evaluated. This could partially explain the link between PB exposure and infertility.

Thymic atrophy induced by Plasmodium berghei ANKA and Plasmodium yoelii 17XL infection.

The thymus is the anatomical site where T cells undergo a complex process of differentiation, proliferation, selection, and elimination of autorreactive cells which involves molecular signals in different intrathymic environment. However, the immunological functions of the thymus can be compromised upon exposure to different infections, affecting thymocyte populations. In this work, we investigated the impact of malaria parasites on the thymus by using C57BL/6 mice infected with Plasmodium berghei ANKA and Plasmodium yoelii 17XL; these lethal infection models represent the most severe complications, cerebral malaria, and anemia respectively. Data showed a reduction in the thymic weight and cellularity involving different T cell maturation stages, mainly CD4-CD8- and CD4+CD8+ thymocytes, as well as an increased presence of apoptotic cells, leading to significant thymic cortex reduction. Thymus atrophy showed no association with elevated serum cytokines levels, although increased glucocorticoid levels did. The severity of thymic damage in both models reached the same extend although it occurs at different stages of infection, showing that thymic atrophy does not depend on parasitemia level but on the specific host-parasite interaction.

Detection of blaCTX-M-15 in an integrative and conjugative element in four extensively drug-resistant Haemophilus parainfluenzae strains causing urethritis.

Haemophilus parainfluenzae is a commensal organism with rising numbers of multidrug-resistant (MDR) strains. This pathogen is of increasing clinical relevance in urogenital infection. The aim of this work was to identify and characterise the molecular mechanisms of resistance associated with four cephalosporin-resistant H. parainfluenzae strains collected from patients with urethritis. Antimicrobial resistance was determined by microdilution following European Committee on Antimicrobial Susceptibility Testing criteria. Strains were then analysed by whole-genome sequencing to determine clonal relationship and the molecular basis of antimicrobial resistance. Finally, a phylogenetic analysis was performed on all urogenital MDR strains of H. parainfluenzae previously isolated in our hospital. All strains were resistant to ß-lactams, macrolides, tetracycline, fluoroquinolones, chloramphenicol, cotrimoxazole, and aminoglycosides. The resistance profile was compatible with the presence of an extended-spectrum ß-lactamase (ESBL). Whole-genome sequencing detected blaCTX-M-15 that conferred high minimum inhibitory concentrations to cephalosporins in two novel integrative and conjugative elements (ICEHpaHUB6 and ICEHpaHUB7) that also harboured a blaTEM-1 ß-lactamase. This study shows a novel blaCTX-M-15 ESBL carried in an integrative conjugative element in four extensively drug-resistant H. parainfluenzae strains. This resistance determinant could be transmitted to other sexually transmitted pathogens and this is a cause for concern.

[Translated article] Design and comparison of bone substitutes. Study of in vivo behaviour in a rabbit model.

AIM: To compare the in vivo bone formation capacity of of biomaterials designed as bone substitutes with respect to iliac crest autograft, one based on carbonate hydroxiapatite and the other one on bioactive mesoporous glass. MATERIALS AND METHODS: Experimental study consisting on 14 adult female New Zeland rabbits where a critical defect was made in the rabbit radius bone. The sample was divided into four groups: defect without material, with iliac crest autograft, with carbonatehydroxyapatite scaffold, and with bioactive mesoporous glass scaffold. Serial X-ray studies were carried out at 2, 4, 6 and 12 weeks and a microCT study at euthanasia at 6 and 12 weeks. RESULTS: In the X-ray study, autograft group showed the highest bone formation scores. Both groups of biomaterials presented bone formation similar and greater than the defect without material, but always less than in the autograft group. The results of the microCT study showed the largest bone volume in the study area in the autograft group. The groups with bone substitutes presented greater bone volume than the group without material but always less than the autograft group. CONCLUSION: Both scaffolds seem to promote bone formation but are not capable of reproducing the characteristics of autograft. Due to their different macroscopic characteristics, each one could be suitable for a different type of defect.

Desing and comparison of bone substitutes. Study of in vivo behavior in a rabbit model. / Diseño y comparativa de biomateriales para el tratamiento de defectos óseos. Estudio de su comportamiento in vivo en modelo animal de conejo.

AIM: Compare bone formation capacity in vivo of two types of biomaterials designed as bone substitutes with respect to iliac crest autograft, one based on carbonate hydroxyapatites and the other one on bioactive mesoporous glass. MATERIALS AND METHODS: Experimental study consisting on 14 adult female New Zeland rabbits where a critical defect was made in the rabbit radius bone. The sample was divided into four groups: defect without material, with iliac crest autograft, with carbonatehydroxyapatite support, and with bioactive mesoporous glass support. Serial X-ray studies were carried out at 2, 4, 6 and 12 weeks and a microCT study at euthanasia at 6 and 12 weeks. RESULTS: In the X-ray study, autograft group showed the highest bone formation scores. Both groups of biomaterials presented bone formation similar and greater than the defect without material, but always less than in the autograft group. The results of the microCT study showed the largest bone volume in the study area in the autograft group. The groups with bone substitutes presented greater bone volume than the group without material but always less than in the autograft group. CONCLUSION: Both supports seem to promote bone formation but are not capable of reproducing the characteristics of autograft. Due to their different macroscopic characteristics, each one could be suitable for a different type of defect.

Autonomic function and its relationship with central obesity and hemodynamic variables in obese and overweight adults / Función autonómica y su relación con la obesidad central y las variables hemodinámicas en adultos obesos y con sobrepeso

Introduction: central obesity is associated with an autonomic dysfunction characterized by an increase in sympathetic activity and a reduction in vagal tone, leading to a decrease in heart rate variability. Objective: we aimed to analyze the relationship between the time and frequency domains of heart rate variability with central obesity, and its hemodynamic variables in normal-weight, overweight and obese adults. Methods: a total of 65 adults were evaluated (25.4 ± 3.2 years old) and distributed in 3 groups: normal weight group (NW group), overweight group (OW group) and obese group (OB group). Heart rate variability parameters at rest and both anthropometric and hemodynamic variables were recorded. Results: the results showed a positive correlation between waist circunference and LF/HF ratio in the OW (p = 0.0008; r = 0.6607; r2 = 0.4365) and OB (p = 0.0001; r = 0.8286; r2 = 0.6866) groups. The waist-to-height ratio showed significant differences with HF in the NW, OW, and OB groups. The variables related to the parasympathetic system (SDNN, RMSSD, pNN50, HF) in the OB and OW groups showed a decrease in values when compared to the NW group. Likewise, the variable related to the sympathetic system (LF) in the OB and OW groups increased its values when compared with the NW group. The LF/HF ratio increased from the NW group to the OW and OB groups (1.6 ± 0.7; 2.5 ± 1.8 and 3.3 ± 0.7). Conclusion: overweight and obese adults present a modulation of sympathetic activity predominance at rest. This increased activity is represented by the time and frequency domains of heart rate variability, having an important correlation with waist circumference and waist-to-height ratio (AU)

Introducción: la obesidad central se asocia con una disfunción autonómica caracterizada por una mayor actividad simpática y reducción del tono vagal, conduciendo a una disminución de la variabilidad de la frecuencia cardíaca (VFC). Objetivo: analizar la relación entre los dominios de tiempo y frecuencia de la VFC con la obesidad central y sus variables hemodinámicas en adultos con peso normal, sobrepeso y obesidad. Metodología: participaron 65 adultos (25,4 ± 3,2 años) distribuidos en 3 grupos: peso normal (grupo NW), sobrepeso (grupo OW) y obesidad (grupo OB). Se registraron los parámetros de la VFC y las variables antropométricas y hemodinámicas. Resultados: se observó una correlación positiva entre la circunferencia de la cintura y la relación LF/HF en el grupo OW (p = 0,0008; r = 0,6607; r2 = 0,4365) y OB (p = 0,0001; r = 0,8286; r2 = 0,6866). La relacion cintura/altura mostró una diferencia significativa con la HF en los grupos NW, OW y OB. La actividad parasimpática (SDNN, RMSSD, pNN50, HF) de los grupos OB y OW evidenció una disminución de los valores en comparación con el grupo NW. La actividad simpática (LF) en el grupo OB y OW presentó mayores valores que en el grupo NW. La relación LF/HF aumentó del grupo NW hacia el OW y el OB (1,6 ± 0,7; 2,5 ± 1,8 y 3,3 ± 0,7). Conclusiones: el sobrepeso y la obesidad presentan una predominancia de la actividad simpática en reposo. Este aumento de la actividad está representado en el dominio de tiempo y frecuencia de la VFC y, además, presenta una correlación importante con la circunferencia de la cintura y la relación cintura/altura (AU)

Mesoporous bioactive glasses for regenerative medicine.

Stem cells are the central element of regenerative medicine (RM). However, in many clinical applications, the use of scaffolds fabricated with biomaterials is required. In this sense, mesoporous bioactive glasses (MBGs) are going to play an important role in bone regeneration because of their striking textural properties, quick bioactive response, and biocompatibility. As other bioactive glasses, MBGs are mainly formed by silicon, calcium, and phosphorus oxides whose ions play an important role in cell proliferation as well as in homeostasis and bone remodeling process. A common improvement of bioactive glasses for RM is by adding small amounts of oxides of elements that confer them additional biological capacities, including osteogenic, angiogenic, antibacterial, anti-inflammatory, hemostatic, or anticancer properties. Moreover, MBGs are versatile in terms of the different ways in which they can be processed, such as scaffolds, fibers, coatings, or nanoparticles. MBGs are unique because their textural properties are so high that they still exhibit outstanding bioactive responses even after adding extra inorganic ions or being processed as scaffolds or nanoparticles. Moreover, they can be further improved by loading with biomolecules, drugs, and stem cells. This article reviews the state of the art and future perspectives of MBGs in the field of RM of hard tissues.

[Debate on the return to face-to-face classes in Pandemic]. / Debate sobre el retorno a clases presenciales en Pandemia.

The implications of closing educational establishments during the COVID-19 pandemic and the dis cussion about the opening of them, invite and require us to consider, from different positions and responsibilities, the changes that we must make as a society at the educational level. In this article, a group of health professionals collects information and reflects on the repercussions of returning or not to school activities, in terms of physical and emotional health and academic education. Based on what is known to be protective factors and possible threats to return, it is possible to conclude that each local reality must make its own informed decision, with the participation of all its members, seeking the common good, which favors students, protects teachers, and privileges the role of the educational system in socio-emotional learning. School is a space for containing the emotions and adaptation needs that students and their families have experienced in these uncertain times. We all have a level of responsibility in building a new civilization around these issues that link education, physical and mental health, social collaboration, and individual responsibility. Differences in people's living conditions and unequal opportunities have become more visible than before (others are still hidden) and create an opportunity for changes that we must face together.

Monocyte Locomotion Inhibitory Factor confers neuroprotection and prevents the development of murine cerebral malaria.

Cerebral malaria (CM) is a neurological complication derived from the Plasmodium falciparum infection in humans. The mechanisms involved in the disease progression are still not fully understood, but both the sequestration of infected red blood cells (iRBC) and leukocytes and an exacerbated host inflammatory immune response are significant factors. In this study, we investigated the effect of Monocyte Locomotion Inhibitory Factor (MLIF), an anti-inflammatory peptide, in a well-characterized murine model of CM. Our data showed that the administration of MLIF increased the survival and avoided the neurological signs of CM in Plasmodium berghei ANKA (PbA) infected C57BL/6 mice. MLIF administration down-regulated systemic inflammatory mediators such as IFN-γ, TNF-α, IL-6, CXCL2, and CCL2, as well as the in situ expression of TNF-α in the brain. In the same way, MLIF reduced the expression of CD31, CD36, CD54, and CD106 in the cerebral endothelium of infected animals and prevented the sequestration of iRBC and leucocytes in the brain microvasculature. Furthermore, MLIF inhibited the activation of astrocytes and microglia and preserved the integrity of the blood-brain barrier (BBB). In conclusion, our results demonstrated that the administration of MLIF increased survival and conferred neuroprotection by decreasing neuroinflammation in murine CM.

Impact of the national program More Smiles for Chile on women's quality of life.

More Smiles for Chile (MSCH) is a national program that helps women to access comprehensive dental care. OBJECTIVE: To assess the changes in oral health related quality of life (OHRQoL) of women attending the MSCH program. METHODS: Uncontrolled cohort study including all women registered in the National Health Fund (FONASA), who were at least 20 years old and received dental treatment in the MSCH program during 2016 or 2017 and completed OHIP-7 pre and post treatment. The median was used to describe central tendency and interquartile range to evaluate dispersion. RESULTS: The study included 11782 women in 2016 and 16533 in 2017. The median OHIP-7 scores pre and post treatment were 8 and 6 respectively. Reductions were significant (p⟨0.001) for the total score and OHIP-7 dimensions, especially physical pain, physiological discomfort and psychological disability. CONCLUSION: The OHRQoL of women improved after treatment in the Chilean MSCH program.

Cinética de recuperación del consumo de oxígeno en deportistas federados / Oxygen Uptake Kinetics in Federated Athletes

La cinética de la recuperación del consumo de oxígeno (VO2) es un indicador de la capacidad funcional (CF). El objetivo de este estudio es analizar el comportamiento de la cinética de recuperación del consumo de oxígeno en deportistas de diferentes disciplinas, de acuerdo al sistema energético predominante en cada uno de ellos. Se diseñó un estudio comparativo, no experimental y transversal en 22 sujetos de deportes federados seleccionados correspondientes a Futsal, Halterofilia y Triatlón mediante un muestreo no probabilístico intencionado. Se valoraron las siguientes variables: peso, talla, índice de masa corporal (IMC), presión arterial, perímetro de cintura y cinética del consumo de oxígeno. Los principales resultados muestran que la cinética de recuperación del (VO2) demostró que los deportistas que practican futsal, evidencian una mejor recuperación (p < 0,05) comparado con los deportistas de triatlón y halterofilia

Oxygen uptake kinetics (VO2) is an indicator of functional capacity (CF). The objective of this study is to analyze the oxygen uptake kinetics in athletes of different disciplines, according to the predominant energy system in each one of them. A comparative, non-experimental and cross-sectional study was designed in 22 subjects of selected federated sports corresponding to futsal, weightlifting and triathlon through intentional non-probabilistic sampling. The following variables were assessed: weight, height, body mass index (BMI), blood pressure, waist circumference and oxygen uptake kinetics. The main results show that the oxygen uptake kinetics (VO2) showed that sportsmen who practice futsal, show a better recovery (p <0.05) compared to athletes of triathlon and weightlifting

Development and evaluation of copper-containing mesoporous bioactive glasses for bone defects therapy.

Mesoporous bioactive glasses (MBGs) are gaining increasing interest in the design of new biomaterials for bone defects treatment. An important research trend to enhance their biological behavior is the inclusion of moderate amounts of oxides with therapeutical action such as CuO. MBGs with composition (85-x)SiO2-10-CaO-5P2O5-xCuO (x = 0, 2.5 or 5 mol-%) were synthesized, investigating the influence of the CuO content and some synthesis parameters in their properties. Two series were developed; first one used HCl as catalyst and chlorides as CaO and CuO precursors, second one, used HNO3 and nitrates. MBGs of chlorides family exhibited calcium/copper phosphate nanoparticles between 10 and 20 nm in size. Nevertheless, CuO-containing MBGs of nitrates family showed metallic copper nanoparticles larger than 50 nm as well as quicker in vitro bioactive responses. Thus, MBGs of the nitrate series were coated by an apatite-like layer after 24 h soaked in simulated body fluid (SBF) a remarkably short period for a MBG containing 5% of CuO. A model, focused in the location of copper in the glass network, was proposed to relate nanostructure and in vitro behaviour. Moreover, after 24 h soaked in MEM or THB culture media, all the MBGs released therapeutic amounts of Ca2+ and Cu2+ ions. Because the quick bioactive response in SBF, the capacity to host biomolecules in their pores and to release therapeutic concentrations of Ca2+ and Cu2+ ions, MBGs of the nitrate families are proposed as excellent biomaterials for bone regeneration.

ZnO-mesoporous glass scaffolds loaded with osteostatin and mesenchymal cells improve bone healing in a rabbit bone defect.

The use of 3D scaffolds based on mesoporous bioactive glasses (MBG) enhanced with therapeutic ions, biomolecules and cells is emerging as a strategy to improve bone healing. In this paper, the osteogenic capability of ZnO-enriched MBG scaffolds loaded or not with osteostatin (OST) and human mesenchymal stem cells (MSC) was evaluated after implantation in New Zealand rabbits. Cylindrical meso-macroporous scaffolds with composition (mol %) 82.2SiO2-10.3CaO-3.3P2O5-4.2ZnO (4ZN) were obtained by rapid prototyping and then, coated with gelatin for easy handling and potentiating the release of inorganic ions and OST. Bone defects (7.5 mm diameter, 12 mm depth) were drilled in the distal femoral epiphysis and filled with 4ZN, 4ZN + MSC, 4ZN + OST or 4ZN + MSC + OST materials to evaluate and compare their osteogenic features. Rabbits were sacrificed at 3 months extracting the distal third of bone specimens for necropsy, histological, and microtomography (µCT) evaluations. Systems investigated exhibited bone regeneration capability. Thus, trabecular bone volume density (BV/TV) values obtained from µCT showed that the good bone healing capability of 4ZN was significantly improved by the scaffolds coated with OST and MSC. Our findings in vivo suggest the interest of these MBG complete systems to improve bone repair in the clinical practice.

Multifunctional antibiotic- and zinc-containing mesoporous bioactive glass scaffolds to fight bone infection.

Bone regeneration is a clinical challenge which requires multiple approaches. Sometimes, it also includes the development of osteogenic and antibacterial biomaterials to treat the emergence of possible infection processes arising from surgery. This study evaluates the antibacterial properties of gelatin-coated meso-macroporous scaffolds based on the bioactive glass 80%SiO2-15%CaO-5%P2O5 (mol-%) before (BL-GE) and after being doped with 4% of ZnO (4ZN-GE) and loaded with both saturated and the minimal inhibitory concentrations of one of the antibiotics: levofloxacin (LEVO), vancomycin (VANCO), rifampicin (RIFAM) or gentamicin (GENTA). After physical-chemical characterization of materials, release studies of inorganic ions and antibiotics from the scaffolds were carried out. Moreover, molecular modelling allowed determining the electrostatic potential density maps and the hydrogen bonds of antibiotics and the glass matrix. Antibacterial in vitro studies (in planktonic, inhibition halos and biofilm destruction) with S. aureus and E. coli as bacteria models showed a synergistic effect of zinc ions and antibiotics. The effect was especially noticeable in planktonic cultures of S. aureus with 4ZN-GE scaffolds loaded with VANCO, LEVO or RIFAM and in E. coli cultures with LEVO or GENTA. Moreover, S. aureus biofilms were completely destroyed by 4ZN-GE scaffolds loaded with VANCO, LEVO or RIFAM and the E. coli biofilm total destruction was accomplished with 4ZN-GE scaffolds loaded with GENTA or LEVO. This approach could be an important step in the fight against microbial resistance and provide needed options for bone infection treatment. STATEMENT OF SIGNIFICANCE: Antibacterial capabilities of scaffolds based on mesoporous bioactive glasses before and after adding a 4% ZnO and loading with saturated and minimal inhibitory concentrations of levofloxacin, vancomycin, gentamicin or rifampicin were evaluated. Staphylococcus aureus and Escherichia coli were the infection model strains for the performed assays of inhibition zone, planktonic growth and biofilm. Good inhibition results and a synergistic effect of zinc ions released from scaffolds and antibiotics were observed. Thus, the amount of antibiotic required to inhibit the bacterial planktonic growth was substantially reduced with the ZnO inclusion in the scaffold. This study shows that the ZnO-MBG osteogenic scaffolds are multifunctional tools in bone tissue engineering because they are able to fight bacterial infections with lower antibiotic dosage.

Assessment of trimethoprim-sulfamethoxazole susceptibility testing methods for fastidious Haemophilus spp.

OBJECTIVES: To compare the determinants of trimethoprim-sulfamethoxazole resistance with established susceptibility values for fastidious Haemophilus spp., to provide recommendations for optimal trimethoprim-sulfamethoxazole measurement. METHODS: We collected 50 strains each of Haemophilus influenzae and Haemophilus parainfluenzae at Bellvitge University Hospital. Trimethoprim-sulfamethoxazole susceptibility was tested by microdilution, E-test and disc diffusion using both Mueller-Hinton fastidious (MH-F) medium and Haemophilus test medium (HTM) following EUCAST and CLSI criteria, respectively. Mutations in folA, folP and additional determinants of resistance were identified in whole-genome-sequenced isolates. RESULTS: Strains presented generally higher rates of trimethoprim-sulfamethoxazole resistance when grown on HTM than on MH-F, independent of the methodology used (average MIC 2.6-fold higher in H. influenzae and 1.2-fold higher in H. parainfluenzae). The main resistance-related determinants were as follows: I95L and F154S/V in folA; 3- and 15-bp insertions and substitutions in folP; acquisition of sul genes; and FolA overproduction potentially linked to mutations in -35 and -10 promoter motifs. Of note, 2 of 19 H. influenzae strains (10.5%) and 9 of 33 H. parainfluenzae strains (27.3%) with mutations and assigned as resistant by microdilution were inaccurately considered susceptible by disc diffusion. This misinterpretation was resolved by raising the clinical resistance breakpoint of the EUCAST guidelines to ≤30 mm. CONCLUSIONS: Given the routine use of disc diffusion, a significant number of strains could potentially be miscategorized as susceptible to trimethoprim-sulfamethoxazole despite having resistance-related mutations. A simple modification to the current clinical resistance breakpoint given by the EUCAST guideline for MH-F ensures correct interpretation and correlation with the reference standard method of microdilution.

Cerium (III) and (IV) containing mesoporous glasses/alginate beads for bone regeneration: bioactivity, biocompatibility and reactive oxygen species activity.

A very small number of biomaterials investigated for bone regeneration was reported as able to prevent the oxidative stress. In this study beads based on alginate hydrogel and mesoporous glasses (MG) containing different amounts of cerium oxides (Ce3+/Ce4+) exhibiting antioxidant properties were investigated as a good approach to mimic the action of antioxidant enzymes in our organism. The effect of cerium contents on the bioactivity and biocompatibility of beads were investigated. Moreover, the potential capability of Ce-containing MG to prevent the oxidative stress caused by the activity of reactive oxygen species (ROS) was here investigated for the first time. The increment of cerium oxide from 1.2, to 3.6 and 5.3 mol-% decreases the surface area and porosity of MG and increases the catalase mimetic activity after 168 h. Swelling tests in different cell culture media (D- and α-MEM) demonstrated the rehydration capability of beads. The presence of beads with the highest Ce-contents (3.6 and 5.3 %) improved the proliferation of pre-osteoblastic cells MC3T3-Cl cells. However, the cell differentiation decreased when increased the cerium content. Lactate dehydrogenase assays showed beads are cytocompatible materials. Moreover, oxidative stress tests with H2O2 showed a better response related to cell viability and the elimination of oxidant species when increased cerium content. Beads of glasses with 1.2 and 3.6 % of CeO2 are excellent candidates as bioactive scaffolds for bone regeneration capable of counteract the oxidative stress.

Cerium (III) and (IV) containing mesoporous glasses/alginate beads for bone regeneration: Bioactivity, biocompatibility and reactive oxygen species activity.

A very small number of biomaterials investigated for bone regeneration were reported as able to prevent the oxidative stress. In this study beads based on alginate hydrogel and mesoporous glasses (MG) containing different amounts of cerium oxides (Ce3+/Ce4+) exhibiting antioxidant properties were investigated as a good approach to mimic the action of antioxidant enzymes in our organism. The effect of cerium contents on the bioactivity and biocompatibility of beads were investigated. Moreover, the potential capability of Ce-containing MG to prevent the oxidative stress caused by the activity of reactive oxygen species (ROS) was here investigated for the first time. The increment of cerium oxide from 1.2, to 3.6 and 5.3 mol% decreases the surface area and porosity of MG and increases the catalase mimetic activity after 168 h. Swelling tests in different cell culture media (D- and α-MEM) demonstrated the rehydration capability of beads. The presence of beads with the highest Ce-contents (3.6 and 5.3%) improved the proliferation of pre-osteoblastic cells MC3T3-C1 cells. However, the cell differentiation decreased when increased the cerium content. Lactate dehydrogenase assays showed beads are cytocompatible materials. Moreover, oxidative stress tests with H2O2 showed a better response related to cell viability and the elimination of oxidant species when increased cerium content. Beads of glasses with 1.2 and 3.6% of CeO2 are excellent candidates as bioactive scaffolds for bone regeneration capable of counteract the oxidative stress.

Managing the farmscape for connectivity increases conservation value for tropical bird species with different forest-dependencies.

Land clearing for agricultural use is a primary driver of biodiversity loss and fragmentation of natural ecosystems. Restoring natural habitat connectivity by retaining quality habitats and increasing on-farm tree cover contributes to species' mobility and persistence in agricultural landscapes. Nonetheless, remarkably few studies have quantified the impacts of on-farm practices for species' mobility measured as functional connectivity within the context of farm and broader spatial levels of landscape organization. We tested how adding and removing trees in different configurations on a farm comprised of coffee plantations and cattle pastures can help evaluate species' mobility at the farmscape level (an area comprising the farm plus a 1.5 km buffer area). We coupled bird capture data and scenario modeling to assess species mobility of five neotropical bird species with distinct life history characteristics representing a gradient of forest dependency. We used seven years of mist-netting data to estimate species habitat affinity and to predict species mobility using the Circuitscape model across a 4371 ha farmscape in Costa Rica. Circuitscape allowed us to estimate changes in movement probability and relative changes in resistance to movement that species experience during dispersal (measured as resistance distance and passage area through which species can move) under four farmscape management scenarios. The four land-use scenarios included: (a) the 2011 farmscape land-use composition and configuration, b) converting all existing live fences to post-and-wire fence lines in the farm c) converting simplified coffee agroforests to multistrata coffee agroforests in the farm, and d) placing multistrata live fences around the perimeter of every parcel and roads on the farm. Model results suggest that existing multistrata live fences maintain the sporadic movement of all five species irrespective of forest dependence. Likewise, adding multistrata live fences around individual fields presents a more efficient strategy for increasing species mobility than multistrata coffee agroforestry systems in the assessed farmscape, by doubling the passage areas available to all species, although it created labyrinths with "dead-ends" for two species. While retaining large habitat patches remains important for conservation, managing on-farm connectivity complements these efforts by increasing movement probability and reducing dispersal resistance for forest-dependent bird species.