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1.
Gels ; 10(6)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38920937

ABSTRACT

Acute and chronic wounds present a significant healthcare challenge, requiring innovative solutions for effective treatment. The exploitation of natural by-products with advanced cell regeneration potential and plant-based materials, which possess bioactive properties, is an innovative topic in wound management. This study investigates the potential of donkey gelatin and keratin for blending with natural bioactive extracts such as sumac, curcumin, and oak acorn to fabricate antioxidant and antimicrobial nanofibers with accelerated wound healing processes. The fabricated nanofibers possess good in vitro biocompatibility, except for the sumac-based donkey nanofibers, where cell viability significantly dropped to 56.25% (p < 0.05 compared to non-treated cells). The nanofiber dimensions showed structural similarities to human extracellular matrix components, providing an ideal microenvironment for tissue regeneration. The donkey nanofiber-based sumac and curcumin extracts presented a higher dissolution in the first 10 min (74% and 72%). Curcumin extract showed similar antimicrobial and antifungal performances to rivanol, while acorn and sumac extracts demonstrated similar values to each other. In vitro tests performed on murine fibroblast cells demonstrated high migration rates of 89% and 85% after 24 h in the case of acorn and curcumin nanofibers, respectively, underscoring the potential of these nanofibers as versatile platforms for advanced wound care applications.

2.
PLoS One ; 19(2): e0297803, 2024.
Article in English | MEDLINE | ID: mdl-38359063

ABSTRACT

Marine glycosaminoglycans (GAG) isolated from different invertebrates, such as molluscs, starfish or jellyfish, have been described as unique molecules with important pharmacological applications. Scarce information is available on GAG extract from Rapana venosa marine snail. The aim of this study was to isolate a GAG extract from R. venosa marine snail and to investigate its physicochemical, antioxidant and antiproliferative properties for further biomedical use. The morphology, chemical and elemental composition of the extract were established as well as the sulfate content and N- to O-sulfation ratio. Fourier transform infrared (FTIR) spectra indicated that GAG extract presented similar structural characteristics to bovine heparan sulfate and chondroitin sulfate. The pattern of extract migration in agarose gel electrophoresis and specific digestion with chondroitinase ABC and heparinase III indicated the presence of a mixture of chondroitin sulfate-type GAG, as main component, and heparan sulfate-type GAG. Free radical scavenging and ferric ion reducing assays showed that GAG extract had high antioxidant activity, which slightly decreased after enzymatic treatment. In vitro MTT and Live/Dead assays showed that GAG extract had the ability to inhibit cell proliferation in human Hep-2 cell cultures, at cytocompatible concentrations in normal NCTC clone L929 fibroblasts. This capacity decreased after enzymatic digestion, in accordance to the antioxidant activity of the products. Tumoral cell migration was also inhibited by GAG extract and its digestion products. Overall, GAG extract from R. venosa marine snail exhibited antioxidant and antiproliferative activities, suggesting its potential use as novel bioactive compound for biomedical applications.


Subject(s)
Chondroitin Sulfates , Glycosaminoglycans , Animals , Cattle , Humans , Glycosaminoglycans/pharmacology , Antioxidants/pharmacology , Heparitin Sulfate , Snails
3.
Sci Rep ; 13(1): 4793, 2023 03 23.
Article in English | MEDLINE | ID: mdl-36959235

ABSTRACT

The richness and structure of symbiont assemblages are shaped by many factors acting at different spatial and temporal scales. Among them, host phylogeny and geographic distance play essential roles. To explore drivers of richness and structure of symbiont assemblages, feather mites and seabirds are an attractive model due to their peculiar traits. Feather mites are permanent ectosymbionts and considered highly host-specific with limited dispersal abilities. Seabirds harbour species-rich feather mite communities and their colonial breeding provides opportunities for symbionts to exploit several host species. To unravel the richness and test the influence of host phylogeny and geographic distance on mite communities, we collected feather mites from 11 seabird species breeding across the Atlantic Ocean and Mediterranean Sea. Using morphological criteria, we identified 33 mite species, of which 17 were new or recently described species. Based on community similarity analyses, mite communities were clearly structured by host genera, while the effect of geography within host genera or species was weak and sometimes negligible. We found a weak but significant effect of geographic distance on similarity patterns in mite communities for Cory's shearwaters Calonectris borealis. Feather mite specificity mainly occurred at the host-genus rather than at host-species level, suggesting that previously inferred host species-specificity may have resulted from poorly sampling closely related host species. Overall, our results show that host phylogeny plays a greater role than geography in determining the composition and structure of mite assemblages and pinpoints the importance of sampling mites from closely-related host species before describing mite specificity patterns.


Subject(s)
Mites , Animals , Mediterranean Sea , Birds , Host Specificity , Atlantic Ocean
4.
Int J Mol Sci ; 24(4)2023 Feb 11.
Article in English | MEDLINE | ID: mdl-36835080

ABSTRACT

The bioactivity of the versatile biodegradable biopolymer poly(lactic acid) (PLA) can be obtained by combining it with natural or synthetic compounds. This paper deals with the preparation of bioactive formulations involving the melt processing of PLA loaded with a medicinal plant (sage) and an edible oil (coconut oil), together with an organomodifed montmorillonite nanoclay, and an assessment of the resulting structural, surface, morphological, mechanical, and biological properties of the biocomposites. By modulating the components, the prepared biocomposites show flexibility, both antioxidant and antimicrobial activity, as well as a high degree of cytocompatibility, being capable to induce the cell adherence and proliferation on their surface. Overall, the obtained results suggest that the developed PLA-based biocomposites could potentially be used as bioactive materials in medical applications.


Subject(s)
Lactic Acid , Polymers , Polymers/chemistry , Coconut Oil , Lactic Acid/chemistry , Polyesters/chemistry
5.
Int J Mol Sci ; 24(4)2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36835300

ABSTRACT

The present research aims to describe a new methodology to obtain biocompatible hydrogels based on Aloe vera used for wound healing applications. The properties of two hydrogels (differing in Aloe vera concentration, AV5 and AV10) prepared by an all-green synthesis method from raw, natural, renewable and bioavailable materials such as salicylic acid, allantoin and xanthan gum were investigated. The morphology of the Aloe vera based hydrogel biomaterials was studied by SEM analysis. The rheological properties of the hydrogels, as well as their cell viability, biocompatibility and cytotoxicity, were determined. The antibacterial activity of Aloe vera based hydrogels was evaluated both on Gram-positive, Staphylococcus aureus and on Gram-negative, Pseudomonas aeruginosa strains. The obtained novel green Aloe vera based hydrogels showed good antibacterial properties. In vitro scratch assay demonstrated the capacity of both AV5 and AV10 hydrogels to accelerate cell proliferation and migration and induce closure of a wounded area. A corroboration of all morphological, rheological, cytocompatibility and cell viability results indicates that this Aloe vera based hydrogel may be suitable for wound healing applications.


Subject(s)
Aloe , Hydrogels , Anti-Bacterial Agents , Wound Healing , Biocompatible Materials
6.
J Funct Biomater ; 14(2)2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36826897

ABSTRACT

Mg is a material of choice for biodegradable implants. The main challenge for using Mg in temporary implants is to provide protective surfaces that mitigate its rapid degradation in biological fluids and also confer sufficient cytocompatibility and bacterial resistance to Mg-coated surfaces. Even though carbonate mineralization is the most important source of biominerals, such as the skeletons and shells of many marine organisms, there has been little success in the controlled growth of carbonate layers by synthetic processes. We present here the formation mechanism, antibacterial activity, and cell viability of magnesian calcite biomimetic coatings grown on biodegradable Mg via a green, one-step route. Cell compatibility assessment showed cell viability higher than 80% after 72 h using fibroblast cells (NCTC, clone L929) and higher than 60% after 72 h using human osteoblast-like cells (SaOS-2); the cells displayed a normal appearance and a density similar to the control sample. Antimicrobial potential evaluation against both Gram-positive (Staphylococcus aureus (ATCC 25923)) and Gram-negative (Pseudomonas aeruginosa (ATCC 27853)) strains demonstrated that the coated samples significantly inhibited bacterial adhesion and biofilm formation compared to the untreated control. Calcite coatings grown on biodegradable Mg by a single coating process showed the necessary properties of cell compatibility and bacterial resistance for application in surface-modified Mg biomaterials for temporary implants.

7.
Polymers (Basel) ; 14(24)2022 Dec 18.
Article in English | MEDLINE | ID: mdl-36559911

ABSTRACT

The aim of this study was to obtain biocomposites consisting of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), bacterial cellulose (BC) and α-tocopherol by a melt processing technique for potential use in biomedical applications. The melt processing and roughness of biocomposites were evaluated and compared to sample without BC. The degradation rate of PHBV/BC biocomposites was measured in phosphate buffer saline (PBS) by determining the mass variation and evidencing of thermal and structural changes by differential scanning calorimetry (DSC) and attenuated total reflectance-Fourier transformed infrared spectrometry (ATR-FTIR). The cell viability, cell morphology, cell cycle distribution and total collagen content were investigated on murine NCTC fibroblasts. Overall, the adding of BC to polyester matrix led to an adequate melt processing of biocomposites and increased surface roughness and cytocompatibility, allowing the cells to secrete the extracellular matrix (collagen) and stimulate cell proliferation. Results showed that the PHBV/BC biocomposites were favorable for long-term degradation and could be used for the design of medical devices with controlled degradability.

8.
Elife ; 112022 09 13.
Article in English | MEDLINE | ID: mdl-36097813

ABSTRACT

By capitalising on positive biodiversity-productivity relationships, intercropping provides opportunities to improve agricultural sustainability. Intercropping is generally implemented using commercial seeds that were bred for maximal productivity in monocultures, thereby ignoring the ability of plants to adapt over generations to the surrounding neighbourhood, notably through increased complementarity, that is reduced competition or increased facilitation. This is why using monoculture-adapted seeds for intercropping might limit the benefits of crop diversity on yield. However, the adaptation potential of crops and the corresponding changes in complementarity have not been explored in annual crop systems. Here we show that plant-plant interactions among annual crops shifted towards reduced competition and/or increased facilitation when the plants were growing in the same community type as their parents did in the previous two generations. Total yield did not respond to this common coexistence history, but in fertilized conditions, we observed increased overyielding in mixtures with a common coexistence history. Surprisingly, we observed character convergence between species sharing the same coexistence history for two generations, in monocultures but also in mixtures: the six crop species tested converged towards taller phenotypes with lower leaf dry matter content. This study provides the first empirical evidence for the potential of parental diversity affecting plant-plant interactions, species complementarity and therefore potentially ecosystem functioning of the following generations in annual cropping systems. Although further studies are required to assess the context-dependence of these results, our findings may still have important implications for diversified agriculture as they illustrate the potential of targeted cultivars to increase complementarity of species in intercropping, which could be achieved through specific breeding for mixtures.


Plants have two ways of interacting with each other: they can compete with each other if they use the same resources; or they can 'help' each other in what is known as facilitation, for example, when a larger plant protects a smaller plant in harsh environments. These interactions can vary over several generations in response to changes in the environment or the surrounding plant community. For instance, in plant communities formed by many different species, like in most natural systems, competition usually decreases over time as the plants 'learn' to grow together. In agriculture, intercropping ­ defined as growing at least two species of crop at the same time on the same field ­ takes advantage from a reduction in competition. The idea is that planting two species that grow differently together will lead to less competition than having a single crop because the two species will use slightly different resources, or use them at different times. However, intercropping has traditionally overlooked changes in the interactions between plants as a result of the crop species evolving after being grown together for generations. Indeed, farmers that practice intercropping generally use standard seeds that have been bred to produce high yields when planted on their own, in what is known as monoculture. If plants can adapt and become less competitive when they are grown together over several generations, then using these standard seeds might limit the success of intercropping. Stefan, Engbersen and Schöb wanted to know whether crop species adapt to the levels of plant diversity surrounding them over generations, and if so, how they do it. To find this out, they investigated how competition and facilitation changed when six crop species (wheat, oat, lentil, coriander, flax and camelina) that grow annually were grown together in different combinations over several generations. Stefan, Engbersen and Schöb started off with seeds normally used for growing these crops on their own, and planted them either on their own, or in different combinations of two or four species. They then repeated the experiment over the course of three years, each year using seeds from the previous year, recording both crop yields and changes in how the plants interacted with each other. The experiments showed that interactions among these annual crops shifted towards reduced competition and/or increased facilitation when the plants were growing alongside the same crops as their parents did in the previous two generations. Improving and promoting the development of intercropping is essential for agricultural sustainability, as it could offer alternatives to intensive monocultures (crops grown on their own that require increased resources). Stefan, Engbersen and Schöb's findings are relevant for programmes aimed at developing seeds for intercropping, as they highlight the importance of including diversity when developing these seeds. However, before these results can be used in the field, longer experiments (of more than three generations) in different environments should be carried out to confirm the findings. Another question that remains open is what the mechanisms underlying adaptations to intercropping are: more in-depth research will be needed to determine whether the changes observed have a genetic basis.


Subject(s)
Ecosystem , Plant Breeding , Agriculture/methods , Biodiversity , Crops, Agricultural/genetics
9.
Polymers (Basel) ; 14(18)2022 Sep 17.
Article in English | MEDLINE | ID: mdl-36146031

ABSTRACT

Bioactive collagen-chitosan-lemongrass (COL-CS-LG) membranes were prepared by casting method and analyzed for potential biomedical applications. For COL-CS-LG membranes, LG essential oil release, antioxidant properties, in vitro cytotoxicity and antimicrobial assessments were conducted, as well as free radical determination after gamma irradiation by chemiluminescence, and structural characteristics analysis through Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Differential Scanning Calorimetry (DSC). The evaluation of non-isothermal chemiluminescence after gamma radiation exposure to COL-CS-LG membranes revealed a slowing down of the oxidation process at temperatures exceeding 200 °C, in correlation with antioxidant activity. Antimicrobial properties and minimum inhibitory concentrations were found to be in correlation with cytotoxicity limits, offering the optimum composition for designing new biomaterials.

10.
Biomedicines ; 10(2)2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35203472

ABSTRACT

(1) Background: Acute kidney injury (AKI) is a serious complication of hematopoietic stem cell transplantation (HSCT). (2) Methods: The aim was to identify the incidence, severity, and risk factors for AKI during the first 100 days after allo-HSCT; we performed a prospective observational study on 135 consecutive patients. (3) Results: The mean age was 38.3 ± 11.9 years (50.6% females), AKI developed in 93 patients (68.9%), the median time of appearance was 28 days, and the mean serum creatinine at the time of AKI was 1.8 ± 0.8 mg/dL. A total of 36 (38.7%) patients developed stage 1 AKI, 33 (35.5%) patients developed stage 2, and 24 (25.8%) patients developed stage 3; eight (8.6%) patients required temporary hemodialysis, and the mortality rate in these patients was 87.5%. Death was twice as frequent in the AKI subgroup, without statistical significance. Cyclosporine overdose (HR = 2.36, 95% CI: 1.45-3.85, p = 0.001), tacrolimus overdose (HR = 4.72, 95% CI: 2.22-10.01, p < 0.001), acute graft-versus-host disease (aGVHD) (HR = 1.96, 95% CI: 1.13-3.40, p = 0.01), and CRP level (HR = 1.009, 95% CI: 1.007-1.10, p < 0.001) were independent risk factors for AKI. Sepsis (HR = 5.37, 95% CI: 1.75-16.48, p = 0.003) and sinusoidal obstruction syndrome (HR = 5.10, 95% CI: 2.02-12.85, p = 0.001) were found as independent risk factors for AKI stage 3. (4) Conclusions: AKI occurs with high incidence and increased severity after allo-HSCT. Careful monitoring of calcineurin inhibitors and proper management of sepsis may reduce this risk.

11.
Ecol Appl ; 32(1): e02479, 2022 01.
Article in English | MEDLINE | ID: mdl-34657349

ABSTRACT

Increasing biodiversity generally enhances productivity through selection and complementarity effects not only in natural, but also in agricultural, systems. However, the quest to explain why diverse cropping systems are more productive than monocultures remains a central goal in agricultural science. In a mesocosm experiment, we constructed monocultures, two- and four-species mixtures from eight crop species with or without fertilizer and both in temperate Switzerland and dry, Mediterranean Spain. We measured physical factors and plant traits and related these in structural equation models to selection and complementarity effects to explain seed yield differences between monocultures and mixtures. Increased crop diversity increased seed yield in Switzerland. This positive biodiversity effect was driven to almost the same extent by selection and complementarity effects, which increased with plant height and specific leaf area (SLA), respectively. Also, ecological processes driving seed yield increases from monocultures to mixtures differed from those responsible for seed yield increases through the diversification of mixtures from two to four species. Whereas selection effects were mainly driven by one species, complementarity effects were linked to larger leaf area per unit leaf weight. Seed yield increases due to mixture diversification were driven only by complementarity effects and were not mediated through the measured traits, suggesting that ecological processes beyond those measured in this study were responsible for positive diversity effects on yield beyond two-species mixtures. By understanding the drivers of positive biodiversity-productivity relationships, we can improve our ability to predict species combinations that enhance ecosystem functioning and can promote sustainable agricultural production.


Subject(s)
Biodiversity , Ecosystem , Biomass , Crop Production , Plants
12.
J BUON ; 26(3): 1080-1087, 2021.
Article in English | MEDLINE | ID: mdl-34268975

ABSTRACT

PURPOSE: The purpose of this study was to evaluate mobilization outcomes with biosimilar pegfilgrastim versus filgrastim in association with chemotherapy as a mobilization strategy for lymphoma patients. METHODS: In the current study we included 32 lymphoma patients that received mobilization therapy and PBSC harvesting at the Bone Marrow Transplantation Department of Fundeni Clinical Institute, Bucharest, Romania between January and December 2019. RESULTS: Pegfilgrastim had beneficial effect when compared to filgrastim in reducing grade IV neutropenia both in the univariate and multivariate logistic models. Additionally, similar efficacy, as mobilization rate, after both filgrastim and pegfilgrastim was observed and no differences were noted between the two groups considering the need for platelet or red blood cell support. CONCLUSION: The use of biosimilar pegfilgrastim is a viable alternative to filgrastim in PBSC mobilization for lymphoma patients.


Subject(s)
Filgrastim/pharmacology , Filgrastim/therapeutic use , Hematologic Agents/pharmacology , Hematologic Agents/therapeutic use , Hematopoietic Stem Cell Mobilization , Lymphoma/drug therapy , Peripheral Blood Stem Cells/drug effects , Polyethylene Glycols/pharmacology , Polyethylene Glycols/therapeutic use , Adult , Female , Humans , Male , Middle Aged , Prospective Studies
13.
Nat Plants ; 7(7): 893-898, 2021 07.
Article in English | MEDLINE | ID: mdl-34168319

ABSTRACT

Resource allocation to reproduction is a critical trait for plant fitness1,2. This trait, called harvest index in the agricultural context3-5, determines how plant biomass is converted to seed yield and consequently financial revenue from numerous major staple crops. While plant diversity has been demonstrated to increase plant biomass6-8, plant diversity effects on seed yield of crops are ambiguous9 and dependent on the production syndrome10. This discrepancy might be explained through changes in the proportion of resources invested in reproduction in response to changes in plant diversity, namely through changes in species interactions and microenvironmental conditions11-14. Here, we show that increasing crop plant diversity from monocultures over two- to four-species mixtures increased annual primary productivity, resulting in overall higher plant biomass and, to a lesser extent, higher seed yield in mixtures compared with monocultures. The difference between the two responses to diversity was due to a reduced harvest index of the eight tested crop species in mixtures, possibly because their common cultivars have been bred for maximum performance in monoculture. While crop diversification provides a sustainable measure of agricultural intensification15, the use of currently available cultivars may compromise larger gains in seed yield. We therefore advocate regional breeding programmes for crop varieties to be used in mixtures that should exploit complementarity16 among crop species.


Subject(s)
Biodiversity , Biomass , Crop Production/methods , Crop Production/statistics & numerical data , Crops, Agricultural/growth & development , Spain , Switzerland
14.
Front Plant Sci ; 12: 668803, 2021.
Article in English | MEDLINE | ID: mdl-34122489

ABSTRACT

Intercropping, i.e., the simultaneous cultivation of different crops on the same field, has demonstrated yield advantages compared to monoculture cropping. These yield advantages have often been attributed to complementary resource use, but few studies quantified the temporal complementarity of nutrient acquisition and biomass production. Our understanding of how nutrient uptake rates of nitrogen (N) and phosphorous (P) and biomass accumulation change throughout the growing season and between different neighbors is limited. We conducted weekly destructive harvests to measure temporal trajectories of N and P uptake and biomass production in three crop species (oat, lupin, and camelina) growing either as isolated single plants, in monocultures or as intercrops. Additionally, we quantified organic acid exudation in the rhizosphere and biological N2-fixation of lupin throughout the growing season. Logistic models were fitted to characterize nutrient acquisition and biomass accumulation trajectories. Nutrient uptake and biomass accumulation trajectories were curtailed by competitive interactions, resulting in earlier peak rates and lower total accumulated nutrients and biomass compared to cultivation as isolated single plants. Different pathways led to overyielding in the two mixtures. The oat-camelina mixture was characterized by a shift from belowground temporal niche partitioning of resource uptake to aboveground competition for light during the growing season. The oat-lupin mixture showed strong competitive interactions, where lupin eventually overyielded due to reliance on atmospheric N and stronger competitiveness for soil P compared to oat. Synthesis: This study demonstrates temporal shifts to earlier peak rates of plants growing with neighbors compared to those growing alone, with changes in uptake patterns suggesting that observed temporal shifts in our experiment were driven by competitive interactions rather than active plant behavior to reduce competition. The two differing pathways to overyielding in the two mixtures highlight the importance of examining temporal dynamics in intercropping systems to understand the underlying mechanisms of overyielding.

15.
Front Microbiol ; 12: 660749, 2021.
Article in English | MEDLINE | ID: mdl-33936016

ABSTRACT

Intensive agriculture has major negative impacts on ecosystem diversity and functioning, including that of soils. The associated reduction of soil biodiversity and essential soil functions, such as nutrient cycling, can restrict plant growth and crop yield. By increasing plant diversity in agricultural systems, intercropping could be a promising way to foster soil microbial diversity and functioning. However, plant-microbe interactions and the extent to which they influence crop yield under field conditions are still poorly understood. In this study, we performed an extensive intercropping experiment using eight crop species and 40 different crop mixtures to investigate how crop diversity affects soil microbial diversity and activity, and whether these changes subsequently affect crop yield. Experiments were carried out in mesocosms under natural conditions in Switzerland and in Spain, two countries with drastically different soils and climate, and our crop communities included either one, two or four species. We sampled and sequenced soil microbial DNA to assess soil microbial diversity, and measured soil basal respiration as a proxy for soil activity. Results indicate that in Switzerland, increasing crop diversity led to shifts in soil microbial community composition, and in particular to an increase of several plant-growth promoting microbes, such as members of the bacterial phylum Actinobacteria. These shifts in community composition subsequently led to a 15 and 35% increase in crop yield in 2 and 4-species mixtures, respectively. This suggests that the positive effects of crop diversity on crop productivity can partially be explained by changes in soil microbial composition. However, the effects of crop diversity on soil microbes were relatively small compared to the effects of abiotic factors such as fertilization (three times larger) or soil moisture (three times larger). Furthermore, these processes were context-dependent: in Spain, where resources were limited, soil microbial communities did not respond to crop diversity, and their effect on crop yield was less strong. This research highlights the potential beneficial role of soil microbial communities in intercropping systems, while also reflecting on the relative importance of crop diversity compared to abiotic drivers of microbiomes and emphasizing the context-dependence of crop-microbe relationships.

16.
Ecol Appl ; 31(4): e02311, 2021 06.
Article in English | MEDLINE | ID: mdl-33630392

ABSTRACT

Implementing sustainable weed control strategies is a major challenge in agriculture. Intercropping offers a potential solution to control weed pressure by reducing the resources available for weeds; however, available research on the relationship between crop diversity and weed pressure and its consequences for crop yield is not yet fully conclusive. In this study, we performed an extensive intercropping experiment using eight crop species and 40 different species mixtures to examine how crop diversity affects weed communities and how the subsequent changes in weeds influence crop yield. Mesocosm experiments were carried out under field conditions in Switzerland and in Spain, which differ drastically in terms of climate, soil and weed community, and included monocultures, two- and four-species mixtures, and a control treatment without crops. Weed communities were assessed in terms of biomass, species number and evenness, and community composition. Results indicate that intercropping reduces weed biomass and diversity in Spain but not in Switzerland. In Switzerland, despite the lack of a crop diversity effect on weeds, crop yield increased with crop species number. Moreover, in Switzerland, where soil resources were abundant, increasing crop yield correlated with reduced weed biomass. In Spain, where water and nutrients were limited, crop yield was not related to weed biomass or diversity. The presented research applies plant community ecology in the context of agricultural crop production systems. We demonstrate that, in our study, increased crop yield in mixtures was not due to increased weed suppression in diverse crop communities, and so must be the result of other ecological processes. We further show that crop-weed relationships vary across environmental conditions; more specifically, our study shows that weeds are less detrimental to crop yield in harsher environments compared to benign abiotic conditions, where alternative strategies are needed to control weed pressure and ensure the yield benefits provided by intercropping.


Subject(s)
Crops, Agricultural , Weed Control , Agriculture , Plant Weeds , Spain , Switzerland
17.
Biomed Mater ; 16(3)2021 03 01.
Article in English | MEDLINE | ID: mdl-33571971

ABSTRACT

Severe skin injuries, including burns, represent a real concern for the global health-care system and therefore, there is an increased interest in developing wound dressings, in order to stimulate and enhance skin tissue repair. The aim of this study was to design novel hybrid materials, biomimetic to skin extracellular matrix and enriched with silver nanoparticles (nAg), in order to provide both dermal tissue regeneration and antimicrobial activity. Two material variants (variant A and variant B) consisting of type I collagen (COL), chondroitin sulfate (CS) and k-elastin peptides (EL) enriched with positively-charged nAg, were conditioned as membranes. UV exposure ensured both sterilisation and cross-linking of the materials. Physico-chemical characterization of the hybrid biomaterials showed values of density and swelling degree higher than those of COL membrane, while the process ofin vitrodegradation followed a similar pattern. Infrared spectroscopy and x-ray diffraction indicated alterations of the characteristic structural features and crystallinity of COL after blending with CS and EL and nAg embedding. Scanning electron microscopy observations revealed different surface morphologies of the hybrid membranes, according to their composition.In vitrostudies on L929 fibroblasts and HaCaT keratinocytes showed that both hybrid membranes exhibited good cytocompatibility and promoted higher cell proliferation compared to COL sample, as evaluated by MTT and Live/Dead assays. The presence of actin filaments highlighted by fluorescent labelling confirmed the fibroblast and keratinocyte adhesion onto the surface of hybrid membranes. Most importantly, both materials showed an increased wound healing ability in anin vitroscratch assay model, stimulating cell migration at 24 h post-seeding. In addition, good antimicrobial activity was recorded, especially against Gram-positive bacterial strain. Altogether, our findings recommend COL-CS-EL-nAg hybrid membranes as good candidates for wound healing acceleration and bioengineering of skin tissue.


Subject(s)
Metal Nanoparticles , Silver , Biomimetics , Collagen/chemistry , Extracellular Matrix , Fibroblasts , Metal Nanoparticles/chemistry , Silver/chemistry , Wound Healing
18.
J Clin Med ; 9(8)2020 Jul 28.
Article in English | MEDLINE | ID: mdl-32731502

ABSTRACT

Adult T-cell leukemia/lymphoma (ATLL) is a rare and aggressive mature T-cell malignancy caused by the human T lymphoma virus I (HTLV-I) affecting 3-5% of HTLV-1 carriers and is usually diagnosed in endemic regions. Romania is a region with high prevalence of HTLV-1 infection and ATLL and with low median age at diagnosis for aggressive types. We performed a retrospective analysis of post-transplant outcome in the first Romanian patients with ATLL receiving hematopoietic stem cell allotransplant. The study population included eight patients (three males, five females), with median age of 39.5 (range 26-57), with acute (one case) and lymphoma type (seven cases) that received peripheral stem cells (PBSC) from matched related (MRD) and unrelated donors (MUD) after reduced intensity conditioning. Graft versus host disease (GVHD) developed in six patients. Relapse occurred in four cases (50%) at a median time of 5-months post-transplant. Six patients died: four cases with disease-related deaths and two patients with GVHD-related deaths. The median survival post-transplant was 19.5 months (range 2.3-44.2 months). The post-transplant survival at 1-year was 62.5%, at 2-years 50%, and at 3-years 37.5%. In our opinion allogeneic transplant improves outcome in aggressive type ATLL.

19.
Materials (Basel) ; 13(14)2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32679796

ABSTRACT

Concentrated collagen hydrolysate (HC10CC), rabbit collagen glue (RCG), and keratin hydrolysate (KH) were investigated in terms of their extraction from mammalian by-products and processing by electrospinning. The electrospun nanofibers were characterized by scanning electron microscopy coupled with the energy dispersive X-ray spectroscopy (SEM/EDS), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), and indentation tests. The cytotoxicity of the electrospun nanofibers was conducted on L929 fibroblast cells using MTT and LDH assays and cell morphology observations. The electrospun RCG and KH nanofibers morphology showed an average size of nanofibers ranging between 44 and 410 nm, while the electrospun HC10CC nanofibers exhibited higher sizes. The ATR-FTIR spectra performed both on extracted proteins and electrospun nanofibers showed that the triple helix structure of collagen is partially preserved. The results were in agreement with the circular dichroism analysis for protein extracts. Furthermore, the viscoelastic properties of electrospun KH nanofibers were superior to those of electrospun RCG nanofibers. Based on both in vitro quantitative and qualitative analysis, the electrospun nanofibers were not cytotoxic, inducing a healthy cellular response. The results of new electrospun protein-based nanofibers may be useful for further research on bioactive properties of these nanofibers for tissue engineering.

20.
Glob Chang Biol ; 26(5): 3052-3064, 2020 05.
Article in English | MEDLINE | ID: mdl-32061109

ABSTRACT

Climate change is driving species' range shifts, which are in turn disrupting species interactions due to species-specific differences in their abilities to migrate in response to climate. We evaluated the consequences of asynchronous range shifts in an alpine plant-pollinator community by transplanting replicated alpine meadow turfs downslope along an elevational gradient thereby introducing them to warmer climates and novel plant and pollinator communities. We asked how these novel plant-pollinator interactions affect plant reproduction. We found that pollinator communities differed substantially across the elevation/temperature gradient, suggesting that these plants will likely interact with different pollinator communities with warming climate. Contrary to the expectation that floral visitation would increase monotonically with warmer temperatures at lower elevations, visitation rate to the transplanted communities peaked under intermediate warming at midelevation sites. In contrast, visitation rate generally increased with temperature for the local, lower elevation plant communities surrounding the experimental alpine turfs. For two of three focal plant species in the transplanted high-elevation community, reproduction declined at warmer sites. For these species, reproduction appears to be dependent on pollinator identity such that reduced reproduction may be attributable to decreased visitation from key pollinator species, such as bumble bees, at warmer sites. Reproduction in the third focal species appears to be primarily driven by overall pollinator visitation rate, regardless of pollinator identity. Taken together, the results suggest climate warming can indirectly affect plant reproduction via changes in plant-pollinator interactions. More broadly, the experiment provides a case study for predicting the outcome of novel species interactions formed under changing climates.


Subject(s)
Flowers , Pollination , Animals , Bees , Climate Change , Plants , Reproduction
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