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1.
J Environ Manage ; 357: 120715, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38579465

RESUMO

The effluents from conventional wastewater treatment plants (WWTP), even if accomplishing quality regulations, substantially differ in their characteristics with those of waters in natural environments. Constructed wetlands (CWs) serve as transitional ecosystems within WWTPs, mitigating these differences and restoring natural features before water is poured into the natural environment. Our study focused on an experimental surface-flow CW naturalizing the WWTP effluent in a semiarid area in Eastern Spain. Despite relatively low pollutant concentrations entering the CW, it effectively further reduced settled organic matter and nitrogen. Dissolved organic matter (DOM) reaching the CW was mainly protein-like, yet optical property changes in the DOM indicated increased humification, aromaticity, and stabilization as it flowed through the CW. Flow cytometry analysis revealed that the CW released less abundant but more active bacterial populations than those received. MiSeq Illumina sequencing highlighted changes in the prokaryotic community composition, with phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria dominating the CW outflow. Functional prediction tools (FaproTax and PICRUSt2) demonstrated a shift towards microbial guilds aligned with those of the natural aquatic environments, increased aerobic chemoheterotrophs, photoautotrophs, and metabolic reactions at higher redox potentials. Enhanced capabilities for degrading plant material correlated well with changes in the DOM pool. Our findings emphasize the role of CWs in releasing biochemically stable DOM and functionally suited microbial populations for natural receiving environments. Consequently, we propose CWs as a naturalization nature-based solution (NBS) in water-scarce regions like the Mediterranean, where reclaimed discharged water can significantly contribute to ecosystem's water resources compared to natural flows.


Assuntos
Águas Residuárias , Áreas Alagadas , Ecossistema , Cidadania , Bactérias , Matéria Orgânica Dissolvida , Região do Mediterrâneo , Eliminação de Resíduos Líquidos
2.
Proc Biol Sci ; 291(2020): 20232768, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38565154

RESUMO

Prior research on metacommunities has largely focused on snapshot surveys, often overlooking temporal dynamics. In this study, our aim was to compare the insights obtained from metacommunity analyses based on a spatial approach repeated over time, with a spatio-temporal approach that consolidates all data into a single model. We empirically assessed the influence of temporal variation in the environment and spatial connectivity on the structure of metacommunities in tropical and Mediterranean temporary ponds. Employing a standardized methodology across both regions, we surveyed multiple freshwater taxa in three time periods within the same hydrological year from multiple temporary ponds in each region. To evaluate how environmental, spatial and temporal influences vary between the two approaches, we used nonlinear variation partitioning analyses based on generalized additive models. Overall, this study underscores the importance of adopting spatio-temporal analytics to better understand the processes shaping metacommunities. While the spatial approach suggested that environmental factors had a greater influence, our spatio-temporal analysis revealed that spatial connectivity was the primary driver influencing metacommunity structure in both regions. Temporal effects were equally important as environmental effects, suggesting a significant role of ecological succession in metacommunity structure.


Assuntos
Água Doce , Lagoas , Clima , Análise Espaço-Temporal , Ecossistema
3.
RSC Med Chem ; 15(2): 519-538, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38389895

RESUMO

A multicomponent-derived synthesis of arylidene isoquinolinones decorated with phenolic moieties is described. The series demonstrated good DPPH trapping and, in the case of sinapic acid-containing analogs, excellent activity against lipoperoxidation; EPR also demonstrated that one derivative scavenged hydroxyl radicals. In addition, some compounds showed excellent inhibition of α-glucosidase activity and, according to both Lineweaver-Burk plots and molecular docking, they act as non-competitive or mixed inhibitors. In vitro assay also demonstrated that two compounds significantly reduced the plasma glucose levels after sucrose administration. In summary, the studied isoquinolinones become novel compounds with dual action (antioxidant and α-glucosidase inhibition) against diabetes and related metabolic diseases, whose optimization would lead to more potent candidates.

4.
Chem Biodivers ; 21(2): e202301871, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38320175

RESUMO

This report informs for the first time the chemical constituents of Diospyros xolocotzii and Diospyros digyna, the pesticidal and the acetylcholinesterase (AChE) inhibition potential of some compounds calculated by in silico approaches, the larvicidal activity against Spodoptera frugiperda of available compounds, the AChE inhibition of selected compounds, and the results of the molecular docking of the most active ones with this receptor. From the aerial parts of D. xolocotzii were isolated pentacyclic triterpenes (1-4, 6, 10, 11-13), phytosterols (15-17), and isodiospyrin (18), whereas the analysis of aerial parts of D. digyna conducted to the isolation of pentacyclic triterpenes (4, 5, 7-9, 11-14), (4S)-shinanolone (19), and scopoletin (20). For comparison purposes, origanal (21) was chemically prepared from 11. The in silico analysis showed that the tested compounds have pesticide potential. The larvicidal activities of 11>13>12 indicated that the increase of the oxidation degree at C-28 increases their bioactivity. Compounds 11 and 21 presented the higher inhibition in the acetylcholinesterase assay, and the higher binding energies, and for the interactionswith AChE by molecular docking. Both Diospyros species are sources of triterpenes with pesticidal potential and the molecular changes in lupane triterpenes correlate with the observed bioactivity and molecular docking.


Assuntos
Diospyros , Praguicidas , Animais , Simulação de Acoplamento Molecular , Diospyros/química , Diospyros/metabolismo , Acetilcolinesterase/metabolismo , Spodoptera , Triterpenos Pentacíclicos
5.
J Appl Microbiol ; 135(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38140942

RESUMO

AIMS: To evaluate the capacity of fourteen sesquiterpenes to enhance the action of known antibiotics against two ß-lactam resistant strains, and to determine a possible mechanism of antibiotic sensitization by assessing their ability to inhibit a ß-lactamase enzyme. METHODS AND RESULTS: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of ß-lactams cefuroxime (CEFM) and cefepime (CPM) against Staphylococcus aureus 23MR and Escherichia coli 82MR strains in the absence and presence of subinhibitory concentrations of fourteen natural sesquiterpenes. (1R,4R)-4H-1,2,3,4-tetrahydro-1-hydroxycadalen-15-oic acid (5), xerantolide (8), estafiatin (11), and ambrosin (12) exhibited the best sensitizing effects in both strains. These compounds were able to reduce the MIC of CEFM by 2-fold (from 15.0 to 7.5 µg/mL) and CPM by 15-fold (from 0.9 to 0.06 µg/mL) in S. aureus 23MR. For E. coli 82MR, the MIC of CEFM was reduced up to 8-fold (from 120.0 to 15.0 µg/mL). In this strain, the activity of 8 and 11 surpassed that of clavulanic acid (positive reference), which reduced the MIC of CEFM from 120.0 to 60.0 µg/mL. To elucidate a possible mechanism of antibiotic sensitization, molecular docking studies were conducted with ß-lactamases. These studies revealed an affinity with the enzymes (energies > -4.93 kcal/mol) by the formation of hydrogen bonds with certain conserved amino acid residues within the active sites. However, the in vitro results indicated only marginal inhibition, with percentages <50%. CONCLUSIONS: The bioevaluations indicate that nine of fourteen sesquiterpenes enhance the action of CEFM and CPM against the ß-lactam resistant strains, and these compounds displayed moderate activity as inhibitors of ß-lactamase.


Assuntos
Escherichia coli , Inibidores de beta-Lactamases , Inibidores de beta-Lactamases/farmacologia , Staphylococcus aureus/metabolismo , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Antibacterianos/química , beta-Lactamas/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo
6.
Sensors (Basel) ; 23(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38139576

RESUMO

This paper introduces the application of a genetic programming (GP)-based method for the automated design and tuning of process controllers, representing a noteworthy advancement in artificial intelligence (AI) within the realm of control engineering. In contrast to already existing work, our GP-based approach operates exclusively in the time domain, incorporating differential operations such as derivatives and integrals without necessitating intermediate inverse Laplace transformations. This unique feature not only simplifies the design process but also ensures the practical implementability of the generated controllers within physical systems. Notably, the GP's functional set extends beyond basic arithmetic operators to include a rich repertoire of mathematical operations, encompassing trigonometric, exponential, and logarithmic functions. This broad set of operations enhances the flexibility and adaptability of the GP-based approach in controller design. To rigorously assess the efficacy of our GP-based approach, we conducted an extensive series of tests to determine its limits and capabilities. In summary, our research establishes the GP-based approach as a promising solution for automating the controller design process, offering a transformative tool to address a spectrum of control problems across various engineering applications.

7.
J Fungi (Basel) ; 9(11)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37998900

RESUMO

We assessed fungal diversity in water and sediment samples obtained from five Arctic lakes in Ny-Ålesund (Svalbard Islands, High Arctic) and five Antarctic lakes on Livingston and Deception Islands (South Shetland Islands), using DNA metabarcoding. A total of 1,639,074 fungal DNA reads were detected and assigned to 5980 ASVs amplicon sequence variants (ASVs), with only 102 (1.7%) that were shared between the two Polar regions. For Arctic lakes, unknown fungal taxa dominated the sequence assemblages, suggesting the dominance of possibly undescribed fungi. The phylum Chytridiomycota was the most represented in the majority of Arctic and Antarctic samples, followed by Rozellomycota, Ascomycota, Basidiomycota, and the less frequent Monoblepharomycota, Aphelidiomycota, Mortierellomycota, Mucoromycota, and Neocallimastigomycota. At the genus level, the most abundant genera included psychrotolerant and cosmopolitan cold-adapted fungi including Alternaria, Cladosporium, Cadophora, Ulvella (Ascomycota), Leucosporidium, Vishniacozyma (Basidiomycota), and Betamyces (Chytridiomycota). The assemblages displayed high diversity and richness. The assigned diversity was composed mainly of taxa recognized as saprophytic fungi, followed by pathogenic and symbiotic fungi.

8.
Microbiol Spectr ; : e0111223, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37732776

RESUMO

Gemmatimonadota is a diverse bacterial phylum commonly found in environments such as soils, rhizospheres, fresh waters, and sediments. So far, the phylum contains just six cultured species (five of them sequenced), which limits our understanding of their diversity and metabolism. Therefore, we analyzed over 400 metagenome-assembled genomes (MAGs) and 5 culture-derived genomes representing Gemmatimonadota from various aquatic environments, hydrothermal vents, sediments, soils, and host-associated (with marine sponges and coral) species. The principal coordinate analysis based on the presence/absence of genes in Gemmatimonadota genomes and phylogenomic analysis documented that marine and host-associated Gemmatimonadota were the most distant from freshwater and wastewater species. A smaller genome size and coding sequences (CDS) number reduction were observed in marine MAGs, pointing to an oligotrophic environmental adaptation. Several metabolic pathways are restricted to specific environments. For example, genes for anoxygenic phototrophy were found only in freshwater, wastewater, and soda lake sediment genomes. There were several genomes from soda lake sediments and wastewater containing type IC/ID ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Various genomes from wastewater harbored bacterial type II RuBisCO, whereas RuBisCO-like protein was found in genomes from fresh waters, soil, host-associated, and marine sediments. Gemmatimonadota does not contain nitrogen fixation genes; however, the nosZ gene, involved in the reduction of N2O, was present in genomes from most environments, missing only in marine water and host-associated Gemmatimonadota. The presented data suggest that Gemmatimonadota evolved as an organotrophic species relying on aerobic respiration and then remodeled its genome inventory when adapting to particular environments. IMPORTANCE Gemmatimonadota is a rarely studied bacterial phylum consisting of a handful of cultured species. Recent culture-independent studies documented that these organisms are distributed in many environments, including soil, marine, fresh, and waste waters. However, due to the lack of cultured species, information about their metabolic potential and environmental role is scarce. Therefore, we collected Gemmatimonadota metagenome-assembled genomes (MAGs) from different habitats and performed a systematic analysis of their genomic characteristics and metabolic potential. Our results show how Gemmatimonadota have adapted their genomes to different environments.

9.
Fitoterapia ; 170: 105655, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37595646

RESUMO

The investigation of the chemical constituents of Datura ceratocaula and D. discolor allowed to isolate three new withanolides, datucerolide A (1) from the first species, and datudiscolides A (8) and B (9) from the second. In addition, seven known withanolides and five ubiquitous compounds were isolated from these plants, along with 27-O-ß-d-glucopyranosyl dinnoxolide A (5), which was obtained as the tetraacetyl derivative 4. All the structures were elucidated by analyses of their spectroscopic and spectrometric data and that of dinnoxolide A (6) was confirmed by X-ray diffraction analysis. The structure 4 was assigned earlier to daturametelin G-Ac and that of 5 to datinolide B, therefore, it will be discussed whether these assignments are correct. On the other hand, the structure of datudiscolide A (8) was previously assigned to the aglycone of dinoxin B (14), however, a revision of its reported NMR data showed inconsistencies with the proposed structure. The inhibitory activity of withanolides 2, 3, 6-8, 12, and 13 against acetylcholinesterase enzyme (AChE) was evaluated. Compounds 6, 7, 12, and 13 exhibited the best activity with IC50 values ranging from 2.8 to 21.5 µM.


Assuntos
Datura , Vitanolídeos , Datura/química , Vitanolídeos/farmacologia , Vitanolídeos/química , Acetilcolinesterase , Estrutura Molecular
10.
Molecules ; 28(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37630284

RESUMO

The first single crystal structure of the homoleptic copper (II) ML2 complex (M=Cu (II), L = curcumin) was obtained and its structure was elucidated by X-ray diffraction showing a square planar geometry, also confirmed by EPR. The supramolecular arrangement is supported by C-H···O interactions and the solvent (MeOH) plays an important role in stabilizing the crystal packing Crystallinity was additionally assessed by XRD patterns. The log P value of the complex (2.3 ± 0.15) was determined showing the improvement in water solubility. The cytotoxic activity of the complex against six cancer cell lines substantially surpasses that of curcumin itself, and it is particularly selective against leukemia (K562) and human glioblastoma (U251) cell lines, with similar antioxidant activity to BHT. This constitutes the first crystal structure of pristine curcumin complexed with a metal ion.

11.
Environ Toxicol Chem ; 42(9): 1857-1866, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37204216

RESUMO

Recovery, recolonization, and adaptation in a chemical stress context are processes that regenerate local populations and communities as well as the functions these communities perform. Recolonization, either by species previously present or by new species able to occupy the niches left empty, refers to a metacommunity process with stressed ecosystems benefiting from the dispersal of organisms from other areas. A potential consequence of recolonization is a limited capacity of local populations to adapt to potentially repeating events of chemical stress exposure when their niches have been effectively occupied by the new colonizers or by new genetic lineages of the taxa previously present. Recovery, instead, is an internal process occurring within stressed ecosystems. More specifically, the impact of a stressor on a community benefits less sensitive individuals of a local population as well as less sensitive taxa within a community. Finally, adaptation refers to phenotypic and, sometimes, genetic changes at the individual and population levels, allowing the permanence of individuals of previously existing taxa without necessarily changing the community taxonomic composition (i.e., not replacing sensitive species). Because these processes are usually operating in parallel in nature, though at different degrees, it seems relevant to try to understand their relative importance for the regeneration of community structure and ecosystem functioning after chemical exposure. In the present critical perspective, we employed case studies supporting our understanding of the underlying processes with the hope to provide a theoretical framework to disentangle the relevance of the three processes for the regeneration of a biological community after chemical exposure. Finally, we provide some recommendations to experimentally compare their relative importance so that the net effects of these processes can be used to parameterize risk-assessment models and inform ecosystem management. Environ Toxicol Chem 2023;42:1857-1866. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Ecossistema , Ecotoxicologia , Humanos , Medição de Risco , Aclimatação
12.
Plants (Basel) ; 12(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36903964

RESUMO

Ageratina pichichensis, is commonly used in traditional Mexican medicine. In vitro cultures were established from wild plant (WP) seeds, obtaining in vitro plant (IP), callus culture (CC), and cell suspension culture (CSC) with the objective to determine total phenol content (TPC) and flavonoids (TFC), as well as their antioxidant activity by DPPH, ABTS and TBARS assays, added to the compound's identification and quantification by HPLC, from methanol extracts obtained by sonication. CC showed significantly higher TPC and TFC than WP and IP, while CSC produced 2.0-2.7 times more TFC than WP, and IP produced only 14.16% TPC and 38.8% TFC compared with WP. There were identified compounds such as epicatechin (EPI), caffeic acid (CfA), and p-coumaric acid (pCA) in in vitro cultures that were not found in WP. The quantitative analysis shows gallic acid (GA) as the least abundant compound in samples, whereas CSC produced significantly more EPI and CfA than CC. Despite these results, in vitro cultures show lower antioxidant activity than WP, for DPPH and TBARS WP > CSC > CC > IP and ABTS WP > CSC = CC > IP. Overall, A. pichichensis WP and in vitro cultures produce phenolic compounds with antioxidant activity, especially CC and CSC, which are shown to be a biotechnological alternative for obtaining bioactive compounds.

13.
Ecology ; 104(1): e3835, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36199222

RESUMO

The metacommunity concept provides a theoretical framework that aims at explaining organism distributions by a combination of environmental filtering, dispersal, and drift. However, few works have attempted a multitaxon approach and even fewer have compared two distant biogeographical regions using the same methodology. We tested the expectation that temperate (mediterranean-climate) pond metacommunities would be more influenced by environmental and spatial processes than tropical ones, because of stronger environmental gradients and a greater isolation of waterbodies. However, the pattern should be different among groups of organisms depending on their dispersal abilities. We surveyed 30 tropical and 32 mediterranean temporary ponds from Costa Rica and Spain, respectively, and obtained data on 49 environmental variables. We characterized the biological communities of bacteria and archaea (from the water column and the sediments), phytoplankton, zooplankton, benthic invertebrates, amphibians and birds, and estimated the relative role of space and environment on metacommunity organization for each group and region, by means of variation partitioning using generalized additive models. Purely environmental effects were important in both tropical and mediterranean ponds, but stronger in the latter, probably due to their larger limnological heterogeneity. Spatially correlated environment and pure spatial effects were greater in the tropics, related to higher climatic heterogeneity and dispersal processes (e.g., restriction, surplus) acting at different scales. The variability between taxonomic groups in the contribution of spatial and environmental factors to metacommunity variation was very wide, but higher in active, compared with passive, dispersers. Higher environmental effects were observed in mediterranean passive dispersers, and higher spatial effects in tropical passive dispersers. The unexplained variation was larger in the tropical setting, suggesting a higher role for stochastic processes, unmeasured environmental factors, or biotic interactions in the tropics, although this difference affected some actively dispersing groups (insects and birds) more than passive dispersers. These results, despite our limitations in comparing only two regions, provide support, for a wide variety of aquatic organisms, for the classic view of stronger abiotic niche constraints in temperate areas compared with the tropics. The heterogeneous response of taxonomic groups between regions also points to a stronger influence of regional context than organism adaptations on metacommunity organization.


Assuntos
Ecossistema , Lagoas , Animais , Invertebrados/fisiologia , Organismos Aquáticos , Zooplâncton
14.
J Youth Adolesc ; 52(2): 406-418, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36396912

RESUMO

Bidirectional associations between bullying and cyberbullying have consistently identified during adolescence. However, little is known about how this relationship works on the within-person level, after controlling for potential overlap at the between-person level. This study examined the bidirectional longitudinal associations between bullying and cyberbullying perpetration and victimization during 18-month period over four time points. A total of 2835 participants, aged 11 to 16 years in time 1 (50% girls; Mage = 13.13, SD = 1.06) were surveyed. Random intercept cross-lagged analyses revealed the stability of bullying perpetration and victimization. Cyberbullying victimization predicted inversely bullying and cyberbullying perpetration. The results indicate spirals of positive long-term associations between bullying (perpetration and victimization) and cyberbullying perpetration but no long-terms spirals of victimization.


Assuntos
Bullying , Vítimas de Crime , Cyberbullying , Adolescente , Feminino , Humanos , Masculino , Estudos Prospectivos , Relações Interpessoais
15.
Eur J Clin Nutr ; 77(5): 511-514, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36474081

RESUMO

The public's trust in the science of avoiding unhealthy weight depends on a radical reform of the design and execution of weight loss programmes and their clinical trials. This Perspective reiterates the longstanding argument for measuring the effectiveness of each component of an intervention on obesity. Body energy content change results from a difference in rates between input and output. These rates are determined by the frequencies of specific patterns of dietary behaviour, physical activity and thermal comfort, plus the cost of resting metabolism. Since fat-free mass changes alongside fat mass, the amount of change in weight from a change in the frequency of a behaviour pattern comes to an asymptote. That step change in weight per unit of behaviour change is measured by regression from the change in frequency of the behaviour that has been maintained from baseline to follow-up. For hard evidence, weight loss programme participants' own words must be used to specify behaviour. In RCTs of multiple-component programmes, sequences of the behaviour patterns to be changed are randomised among groups. The resulting evidence on effective slimming practices can be delivered directly into therapeutic services and public health interventions for the culture investigated.


Assuntos
Obesidade , Programas de Redução de Peso , Humanos , Obesidade/terapia , Exercício Físico , Redução de Peso
16.
Sci Rep ; 12(1): 20257, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36509802

RESUMO

La Palma, Canary Islands, underwent volcanic unrest which culminated in its largest historical eruption. We study this unrest along 2021 using Interferometric Synthetic Aperture Radar (InSAR) and a new improved interpretation methodology, comparing achieved results with the crustal structure. We reproduce the final phase of La Palma volcanic unrest, highligthing a shallow magma accumulation which begins about 3.5 months before the eruption in a crustal volume charactherized by low density and fractured rocks. Our modeling, together with our improved pictures of the crustal structure, allows us to explain the location and characteristics of the eruption and to detect failed eruption paths. These can be used to explain post-eruptive phenomena and hazards to the local population, such as detected gases anomalies in La Bombilla and Puerto Naos. Our results have implications for understanding volcanic activity in the Canaries and volcano monitoring elsewhere, helping to support decision-making and providing significant insights into urban and infrastructure planning in volcanic areas.

17.
Fitoterapia ; 163: 105340, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36283569

RESUMO

From the extracts of stems and leaves as well as of calyxes of Physalis grisea were isolated four withalactols, the new griselactols A (3) and B (6) and the known physapubescin (1) and peruvianolide E (2). Other four known compounds were also isolated, kaempferol 3-O-ß-sophoroside (5) and three sterols. The structures of compounds were elucidated by extensive spectroscopic data analyses, chemical and physical-chemical methods, including electronic circular dichroism (ECD), and by comparison with data described in the literature. The antihyperglycemic activity of the extracts and of the three more abundant metabolites (1, 3, and 5) was evaluated in the α-glucosidase inhibition assay.


Assuntos
Physalis , Physalis/química , Extratos Vegetais/química , Estrutura Molecular , Folhas de Planta , Flores
18.
Front Microbiol ; 13: 900158, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212846

RESUMO

The role of competitive interactions based on resource utilisation was explored in a phototrophic microbial mat from Byers Peninsula (Maritime Antarctica). Shotgun metagenomic profiling of the mat showed a taxonomic and functionally diverse microbial community. The heterotrophic bacterial community was dominated by Proteobacteria, where genera typically found in polar habitats, such as Janthinobacterium, Pseudomonas, and Polaromonas, were highly prevalent. Cyanobacteria played the main role as primary producers, accompanied by diatoms and chlorophytes. To test the potential effects of the inorganic nutrient (N and P) availability on this community, a fully factorial nitrate and phosphorus addition experiment was conducted in situ. The mat exhibited a functional and structural response to the nutrient amendments. Compared to the undisturbed mat, phosphorus fertilisation favoured the growth of (non-heterocystous) cyanobacteria relative to that of diatoms, as indicated by changes in the carotenoid pigment biomarkers. Although no mat accretion was visible, fertilisation improved the phototrophic activity, and, mainly, when P was amended, the production of exopolymeric substances was favoured, whereas further changes in the vertical distribution of primary production activity were observed as well. Illumina amplicon sequencing of the 16S rRNA gene also demonstrated changes in the relative abundance of heterotrophic prokaryotes, which were detectable from the phylum to the genus level and mainly related to the amendment of nitrogen. Predictions made on the functional skills of these shifted prokaryotic communities indicated changes in abundance selecting taxa with a metabolic adaptation to the new nutrient scenarios. They mainly consisted of the enhancement of ecological strategies and metabolic regulatory mechanisms related to the uptake and metabolising of either nitrogen or phosphorus, regulated by its availability whether in a balanced way or not. This study is a pioneer in demonstrating how shifts in the regional dynamic of nutrients might alter the metabolic equilibrium of these initially considered homeostatic benthic communities. They can be accordingly considered as taxonomically diverse microbiomes with a functional repertoire still inclined to respond to the biogeochemical alteration of nutrient cycles, although occurring in a cold extreme environment where biological activity is partially restricted by environmental harshness.

19.
Biomed Pharmacother ; 155: 113708, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36162373

RESUMO

Type 2 diabetes (T2D) in developed countries have a prevalence of 11% with diabetic foot infections as the most common cause of hospitalization and amputation. To achieve healing of the diabetic foot ulcer wounds, appropriate dressings are essential and their effectiveness can be enhanced with nanoparticles, nevertheless ideal combinations of dressing composition and nanodrugs require further testing in humans. We have developed a calcium alginate dressings with ZnO nanoparticles (CAZnODs) for the treatment of diabetic foot ulcers in human patients. To test the efficacy of CAZnODs we designed a randomized controlled clinical experiment on 26 T2D patients with foot ulcers. The patients were randomized into two groups: G1 treatment with calcium alginate with NPs (G1; n = 16), and group 2 received the treatment without NPs (G2, n = 10). The bandage change was performed every 48 h The duration of the protocol was established at 10 weeks. Here, we report healing was achieved in patients, with 75% wound closure in G1 under treatment with NPs of calcium alginate versus 71% in G2 (calcium alginate without NPs) (p = 0.011). The average healing time was 48 days in G1 and 72 days in G2. Our data shows that CAZnODs were well tolerated and did not interfere with the wound healing process. The final wound area and time of healing support the hypothesis that the use of calcium alginate dressings with nanoparticles may induce better tissue regeneration while avoiding T2D complications such as secondary infections.


Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Óxido de Zinco , Humanos , Pé Diabético/tratamento farmacológico , Curativos Hidrocoloides , Óxido de Zinco/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Alginatos/uso terapêutico
20.
Int. j. clin. health psychol. (Internet) ; 22(3): 1-10, Sept. - dec. 2022. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-208419

RESUMO

Background/Objective: The present study aims to explore the dynamics of social anxiety profiles in adolescents over time and the psychosocial effects these dynamics have.Method: A representative sample of Andalusian (southern Spain) adolescents in Secondary Education was drawn. The study used single-stage stratified cluster sampling. A total of 2,140 students aged 11-16 years (47% girls; MageT1 = 13.68, SD = 1.27) were involved at two time points with a six-month interval.Results: The results provided a four-profile structure: low social anxiety, moderate cognitive disturbance, high with difficulties in new situations, and high social anxiety. The latent transition analysis showed a stability in the social anxiety profiles of between 58%-61%. Those adolescents who remained in or transitioned to profiles with higher social anxiety scored worse on peer adjustment, peer victimization and subjective well-being.Conclusions: The study may contribute the improvement of the psychological treatments in social anxiety and reduce adverse effects on peer relationships and well-being by distinguishing the profiles and their dynamics. (AU)


Assuntos
Humanos , Criança , Adolescente , Ansiedade , Ansiedade/classificação , Ansiedade/tratamento farmacológico , Ansiedade/psicologia , Inquéritos e Questionários , Análise de Classes Latentes
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