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1.
Mol Ecol Resour ; : e13996, 2024 Aug 04.
Article in English | MEDLINE | ID: mdl-39099161

ABSTRACT

The analysis of meta-omics data requires the utilization of several bioinformatics tools and proficiency in informatics. The integration of multiple meta-omics data is even more challenging, and the outputs of existing bioinformatics solutions are not always easy to interpret. Here, we present a meta-omics bioinformatics pipeline, Meta-Omics Software for Community Analysis (MOSCA), which aims to overcome these limitations. MOSCA was initially developed for analysing metagenomics (MG) and metatranscriptomics (MT) data. Now, it also performs MG and metaproteomics (MP) integrated analysis, and MG/MT analysis was upgraded with an additional iterative binning step, metabolic pathways mapping, and several improvements regarding functional annotation and data visualization. MOSCA handles raw sequencing data and mass spectra and performs pre-processing, assembly, annotation, binning and differential gene/protein expression analysis. MOSCA shows taxonomic and functional analysis in large tables, performs metabolic pathways mapping, generates Krona plots and shows gene/protein expression results in heatmaps, improving omics data visualization. MOSCA is easily run from a single command while also providing a web interface (MOSGUITO). Relevant features include an extensive set of customization options, allowing tailored analyses to suit specific research objectives, and the ability to restart the pipeline from intermediary checkpoints using alternative configurations. Two case studies showcased MOSCA results, giving a complete view of the anaerobic microbial communities from anaerobic digesters and insights on the role of specific microorganisms. MOSCA represents a pivotal advancement in meta-omics research, offering an intuitive, comprehensive, and versatile solution for researchers seeking to unravel the intricate tapestry of microbial communities.

2.
J Pediatr (Rio J) ; 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39178912

ABSTRACT

OBJECTIVE: The analysis of abdominal radiography is essential for the diagnosis and management of necrotizing enterocolitis (NEC) in newborns (NB). Studies, however, show a lack of agreement among physicians in the interpretation of images. This study aims to evaluate the agreement in the radiological interpretation of the NEC between examiners from different specialties (interexaminer analysis) and between the same examiner at different times (intraexaminer analysis). METHODS: Cross-sectional study for concordance analysis using plain radiographs of the abdomen of NB with suspected or confirmed NEC. The study included two neonatologists (Neo), two surgeons (SU), and two radiologists (RD). The participants filled out a form with questions about the radiographic findings; regarding the presence of intestinal loop distension, the specialists answered subjectively (yes or no) and objectively (calculation of the ratio between loop diameter and lumbar vertebrae measurements). Kappa coefficients were calculated for agreement analysis. RESULTS: A total of 90 radiological images were analyzed. For the interexaminer evaluation, the agreement was low (kappa<0.4) in 30 % of the answers (Neo versus SU), 38 % (Neo versus RD), and 46 % (SU versus RD). In the intraexaminer evaluation, the neonatologist and the surgeon presented substantial or almost perfect agreement in 92 % of the answers, and the radiologist in 77 %. In the evaluation of intestinal loop distention, the greatest agreement between the specialties occurred when done objectively. CONCLUSION: The results confirmed the low intra- and interexaminer agreement in the radiological analysis of the NEC, reinforcing the importance of standardizing the methods of radiological interpretation of the disease.

3.
J Am Chem Soc ; 146(34): 24105-24113, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39143928

ABSTRACT

The quest for sustainable strategies in molecular synthesis has spurred the emergence of photocatalysis as a particularly powerful technique. In recent years, the application of photocatalysis in this context has greatly promoted the development of asymmetric catalysis. Despite the impressive advances, enantioselective photoinduced strong arene C-H activations by cobalt catalysis remain unexplored. Herein, we report a strategy that merges organic photoredox catalysis and enantioselective cobalt-catalyzed C-H activation, enabling the regio- and stereoselective dual functionalization of indoles in an enantioselective fashion. Thereby, the assembly of various chiral indolo[2,3-c]isoquinolin-5-ones was realized with high enantioselectivities of up to 99%. The robustness of the cobaltaphotoredox catalysis was demonstrated through enantioselective C-H activation and annulations in a continuous flow to provide straightforward access to central and axially chiral molecules.

4.
BioData Min ; 17(1): 27, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39198921

ABSTRACT

Cardiovascular diseases are the main cause of death in the world and cardiovascular imaging techniques are the mainstay of noninvasive diagnosis. Aortic stenosis is a lethal cardiac disease preceded by aortic valve calcification for several years. Data-driven tools developed with Deep Learning (DL) algorithms can process and categorize medical images data, providing fast diagnoses with considered reliability, to improve healthcare effectiveness. A systematic review of DL applications on medical images for pathologic calcium detection concluded that there are established techniques in this field, using primarily CT scans, at the expense of radiation exposure. Echocardiography is an unexplored alternative to detect calcium, but still needs technological developments. In this article, a fully automated method based on Convolutional Neural Networks (CNNs) was developed to detect Aortic Calcification in Echocardiography images, consisting of two essential processes: (1) an object detector to locate aortic valve - achieving 95% of precision and 100% of recall; and (2) a classifier to identify calcium structures in the valve - which achieved 92% of precision and 100% of recall. The outcome of this work is the possibility of automation of the detection with Echocardiography of Aortic Valve Calcification, a lethal and prevalent disease.

5.
Int J Mol Sci ; 25(16)2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39201249

ABSTRACT

The periodontium is a complex hierarchical structure composed of alveolar bone, periodontal ligament, cementum, and gingiva. Periodontitis is an inflammatory disease that damages and destroys the periodontal tissues supporting the tooth. Periodontal therapies aim to regenerate the lost tissues, yet current treatments lack the integration of multiple structural/biochemical instructive cues to induce a coordinated regeneration, which leads to limited clinical outcomes. Hierarchical biomaterial scaffolds offer the opportunity to recreate the organization and architecture of the periodontium with distinct compartments, providing structural biomimicry that facilitates periodontal regeneration. Various scaffolds have been fabricated and tested preclinically, showing positive regenerative results. This review provides an overview of the recent research on hierarchical scaffolds for periodontal tissue engineering (TE). First, the hierarchical structure of the periodontium is described, covering the limitations of the current treatments used for periodontal regeneration and presenting alternative therapeutic strategies, including scaffolds and biochemical factors. Recent research regarding hierarchical scaffolds is highlighted and discussed, in particular, the scaffold composition, fabrication methods, and results from in vitro/in vivo studies are summarized. Finally, current challenges associated with the application of hierarchical scaffolds for periodontal TE are debated and future research directions are proposed.


Subject(s)
Biocompatible Materials , Periodontium , Tissue Engineering , Tissue Scaffolds , Humans , Tissue Scaffolds/chemistry , Tissue Engineering/methods , Biocompatible Materials/chemistry , Animals , Regeneration , Periodontal Ligament/cytology , Periodontitis/therapy
6.
Biomedicines ; 12(8)2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39200121

ABSTRACT

PURPOSE: A growing body of evidence has shown that electroencephalography (EEG) is an interesting method of assessing the underlying brain physiology associated with disordered eating. Using EEG, we sought to evaluate brain reactivity to hyper-palatable food cues in undergraduate students with disordered eating behavior (DEB). METHODS: After assessing the eating behaviors of twenty-six undergraduate students using the Eating Attitudes Test (EAT-26), electroencephalographic signals were recorded while the participants were presented with pictures of hyper-palatable food. The current study used a temporospatial principal component analysis (PCA) approach to identify event-related potential (ERP) responses that differed between DEB and non-DEB individuals. RESULTS: A temporospatial PCA applied to the ERPs identified a positivity with a maximum amplitude at 347 ms at the occipital-temporal electrodes in response to pictures of hyper-palatable food. This positivity was correlated with the EAT-26 scores. Participants with DEB showed reduced positivities in this component compared with those without DEB. CONCLUSION: Our findings may reflect greater motivated attention toward hyper-palatable food cues in undergraduate students with DEB. These results are an important step toward obtaining a more refined understanding of specific abnormalities related to reactivity to food cues in this population.

7.
Gels ; 10(7)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-39057446

ABSTRACT

Functional articular cartilage regeneration remains an unmet medical challenge, increasing the interest for innovative biomaterial-based tissue engineering (TE) strategies. Hydrogels, 3D macromolecular networks with hydrophilic groups, present articular cartilage-like features such as high water content and load-bearing capacity. In this study, 3D porous polyethylene glycol diacrylate (PEGDA) hydrogels were fabricated combining the gas foaming technique and a UV-based crosslinking strategy. The 3D porous PEGDA hydrogels were characterized in terms of their physical, structural and mechanical properties. Our results showed that the size of the hydrogel pores can be modulated by varying the initiator concentration. In vitro cytotoxicity tests showed that 3D porous PEGDA hydrogels presented high biocompatibility both with human chondrocytes and osteoblast-like cells. Importantly, the 3D porous PEGDA hydrogels supported the viability and chondrogenic differentiation of human bone marrow-derived mesenchymal stem/stromal cell (hBM-MSC)-based spheroids as demonstrated by the positive staining of typical cartilage extracellular matrix (ECM) (glycosaminoglycans (GAGs)) and upregulation of chondrogenesis marker genes. Overall, the produced 3D porous PEGDA hydrogels presented cartilage-like mechanical properties and supported MSC spheroid chondrogenesis, highlighting their potential as suitable scaffolds for cartilage TE or disease modelling strategies.

8.
Toxics ; 12(7)2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39058164

ABSTRACT

Chlorpyrifos, an organophosphate insecticide widely used to control agricultural pests, poses a significant environmental threat due to its toxicity and persistence in soil and water. Our work aimed to evaluate the acute (survival) and chronic (regeneration, locomotion, and reproduction) toxicity of chlorpyrifos to the non-target freshwater planarian Girardia tigrina. The 48 h lethal concentration (LC50) of the commercial formulation, containing 480 g L-1 of chlorpyrifos, the active ingredient, was determined to be 622.8 µg a.i. L-1 for planarians. Sublethal effects were translated into a significant reduction in locomotion and delayed head regeneration (lowest observed effect concentration-LOEC = 3.88 µg a.i. L-1). Additionally, chlorpyrifos exposure did not affect planarian fecundity or fertility. Overall, this study demonstrates the potential of chlorpyrifos-based insecticides to harm natural populations of freshwater planarians at environmentally relevant concentrations. The observed toxicity emphasizes the need for stricter regulations and careful management of chlorpyrifos usage to mitigate its deleterious effects on aquatic ecosystems. By understanding the specific impacts on non-target organisms like G. tigrina, we can make more informed suggestions regarding the usage and regulation of organophosphate insecticides, ultimately promoting sustainable agricultural practices and environmental conservation.

9.
J Environ Manage ; 366: 121622, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38972185

ABSTRACT

Land-use land-cover (LULC) change contributes to major ecological impacts, particularly in areas undergoing land abandonment, inducing modifications on habitat structure and species distributions. Alternative land-use policies are potential solutions to alleviate the negative impacts of contemporary tendencies of LULC change on biodiversity. This work analyzes these tendencies in the Montesinho Natural Park (Portugal), an area representative of European abandoned mountain rural areas. We built ecological niche models for 226 species of vertebrates (amphibians, reptiles, birds, and mammals) and vascular plants, using a consensus modelling approach available in the R package 'biomod2'. We projected the models to contemporary (2018) and future (2050) LULC scenarios, under four scenarios aiming to secure relevant ecosystem services and biodiversity conservation for 2050: an afforestation and a rewilding scenario, focused on climate-smart management strategies, and a farmland and an agroforestry recovery scenario, based on re-establishing human traditional activities. We quantified the influences of these scenarios on biodiversity through species habitat suitability changes for 2018-2050. We analyzed how these management strategies could influence indices of functional diversity (functional richness, functional evenness and functional dispersion) within the park. Habitat suitability changes revealed complementary patterns among scenarios. Afforestation and rewilding scenarios benefited more species adapted to habitats with low human influence, such as forests and open woodlands. The highest functional richness and dispersion was predicted for rewilding scenarios, which could improve landscape restoration and provide opportunities for the expansion and recolonization of forest areas by native species. The recovery of traditional farming and agroforestry activities results in the lowest values of functional richness, but these strategies contribute to complex landscape matrices with diversified habitats and resources. Moreover, this strategy could offer opportunities for fire suppression and increase landscape fire resistance. An integrative approach reconciling rewilding initiatives with the recovery of extensive agricultural and agroforestry activities is potentially an harmonious strategy for supporting the provision of ecosystem services while securing biodiversity conservation and functional diversity within the natural park.


Subject(s)
Biodiversity , Conservation of Natural Resources , Ecosystem , Farms , Animals , Forests , Climate
10.
Braz J Microbiol ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963475

ABSTRACT

Cryptococcus gattii, an environmental fungus, is one of the agents of cryptococcosis. The influence of agrochemicals on fungal resistance to antifungals is widely discussed. However, the effects of benomyl (BEN) on fungal interaction with different hosts is still to be understood. Here we studied the influence of adaptation to BEN in the interaction with a plant model, phagocytes and with Tenebrio molitor. First, the strain C. gattii L24/01 non-adapted (NA), adapted (A) to BEN, and adapted with further culture on drug-free media (10p) interact with Nicotiana benthamiana, with a peak in the yeast burden on the 7th day post-inoculation. C. gattii L24/01 A and 10p provided lower fungal burden, but these strains increased cell diameter and capsular thickness after the interaction, together with decreased fungal growth. The strains NA and A showed reduced ergosterol levels, while 10p exhibited increased activity of laccase and urease. L24/01 A recovered from N. benthamiana was less engulfed by murine macrophages, with lower production of reactive oxygen species. This phenotype was accompanied by increased ability of this strain to grow inside macrophages. Otherwise, L24/01 A showed reduced virulence in the T. molitor larvae model. Here, we demonstrate that the exposure to BEN, and interaction with plants interfere in the morphophysiology and virulence of the C. gattii.

11.
Angew Chem Int Ed Engl ; : e202407384, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38959168

ABSTRACT

Skeletal molecular editing gained considerable recent momentum and emerged as a uniquely powerful tool for late-stage diversifications. Thus far, superstoichiometric amounts of costly hypervalent iodine(III) reagents were largely required for skeletal indole editing. In contrast, we herein show that electricity enables sustainable nitrogen atom insertion reactions to give bio-relevant quinazoline scaffolds without stoichiometric chemical redox-waste product. The transition metal-free electro-editing was enabled by the oxygen reduction reaction (ORR) and proved robust on scale, while tolerating a variety of valuable functional groups.

12.
ACS Omega ; 9(23): 24987-24997, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38882168

ABSTRACT

Microwave-assisted pyrolysis (MAP) is a cutting-edge technology that converts biomass into fuels, chemicals, and materials. In this study, an Arduino was used to control and automate a MAP system built from a microwave oven with a cordierite chamber filled with silicon carbide. Sugar cane bagasse was pyrolyzed at 250, 350, 450, and 550 °C to validate the MAP system and obtain pyrolytic products with different yields and chemical compositions. Lower temperatures led to high biochar yields, but the highest surface area of 25.14 m2 g-1 was only achieved at 550 °C. By contrast, higher temperatures favored the recovery of pyrolysis liquids. BET and scanning electron microscopy analyses revealed a porous biochar structure, while Fourier transform infrared spectroscopy analysis showed that the availability of functional groups on the biochar surface decreased with an increase in pyrolysis temperature. GC-MS analysis quantified valuable low molecular mass compounds in pyrolysis liquids, including aldehydes, ketones, phenols, and alcohols. With its unprecedented hybrid heating device, the MAP system promoted suitable heating rates (31.9 °C min-1) and precise temperature control (only 19 °C of set point variation), generating pyrolysis products devoid of microwave susceptor interferences. Therefore, MAP provided a rapid, safe, and efficient means of depolymerizing biomass, thus holding promise for biorefinery applications.

13.
ACS Catal ; 14(11): 8160-8167, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38868099

ABSTRACT

Rhodium(III)-catalyzed enantioselective C-H activation has emerged as a powerful tool for assembling enabling chiral molecules. However, this approach is significantly hampered by the cumbersome synthetic routes for preparing chiral rhodium catalysts. In sharp contrast, we herein report on an electrochemical domino catalysis system that exploits an achiral Cp*-rhodium catalyst along with an easily accessible chiral Brønsted base for an enantioselective C-H activation/annulation reaction of alkenes by benzoic acids. Our strategy offers an environmentally benign and most user-friendly approach for assembling synthetically useful chiral phthalides in good enantioselectivity, employing electricity as the sustainable oxidant.

14.
Mol Cell Endocrinol ; 592: 112324, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38944371

ABSTRACT

Genomes and transcriptomes from diverse organisms are providing a wealth of data to explore the evolution and origin of neuropeptides and their receptors in metazoans. While most neuropeptide-receptor systems have been extensively studied in vertebrates, there is still a considerable lack of understanding regarding their functions in invertebrates, an extraordinarily diverse group that account for the majority of animal species on Earth. Cephalochordates, commonly known as amphioxus or lancelets, serve as the evolutionary proxy of the chordate ancestor. Their key evolutionary position, bridging the invertebrate to vertebrate transition, has been explored to uncover the origin, evolution, and function of vertebrate neuropeptide systems. Amphioxus genomes exhibit a high degree of sequence and structural conservation with vertebrates, and sequence and functional homologues of several vertebrate neuropeptide families are present in cephalochordates. This review aims to provide a comprehensively overview of the recent findings on neuropeptides and their receptors in cephalochordates, highlighting their significance as a model for understanding the complex evolution of neuropeptide signaling in vertebrates.

15.
Dalton Trans ; 53(27): 11393-11409, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38899369

ABSTRACT

In this work we disclose a new family of biscyclometallated Ir(III) complexes of the general formula [Ir(C^N)2(N^N)]Cl (IrL1-IrL5), where HC^N is 1-phenyl-ß-carboline and N^N ligands (L1-L5) are different diimine ligands that differ from each other in the number of aromatic rings fused to the bipyridine scaffold. The photophysical properties of IrL1-IrL5 were thoroughly studied, and theoretical calculations were performed for a deeper comprehension of the respective variations along the series. All complexes exhibited high photostability under blue light irradiation. An increase in the number of aromatic rings led to a reduction in the HOMO-LUMO band gap causing a red-shift in the absorbance bands. Although all the complexes generated singlet oxygen (1O2) in aerated aqueous solutions through a photocatalytic process, IrL5 was by far the most efficient photosensitizer. Consequently, IrL5 was highly active in the photocatalytic oxidation of NADH. The formation of aggregates in DMSO at a high concentration (25 mM) was confirmed using different techniques, but was proved to be negligible in the concentration range of biological experiments. Moreover, ICP-MS studies proved that the cellular uptake of IrL2 and IrL3 is much better relative to that of IrL1, IrL4 and IrL5. The antiproliferative activity of IrL1-IrL5 was investigated in the dark and under blue light irradiation against different cancer cell lines. Complexes IrL1-IrL4 were found to be cytotoxic under dark conditions, while IrL5 turned out to be weakly cytotoxic. Despite the low cellular uptake of IrL5, this derivative exhibited a high increase of cytotoxicity upon blue light irradiation resulting in photocytotoxicity indexes (PI) up to 38. IrL1-IrL4 showed lower photocytotoxicity indexes ranging from 1.3 to 17.0. Haemolytic experiments corroborated the compatibility of our complexes with red blood cells. Confocal microscopy studies proved their accumulation in mitochondria, leading to mitochondrial membrane depolarization, and ruled out their localization in lysosomes. Overall, the mitochondria-targeted activity of IrL5, which inhibits considerably the viability of cancer cells upon blue light irradiation, allows us to outline this PS as a new alternative to traditional chemotherapeutic agents.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Iridium , Photochemotherapy , Photosensitizing Agents , Humans , Iridium/chemistry , Iridium/pharmacology , Ligands , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Photosensitizing Agents/chemical synthesis , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/chemical synthesis , Drug Screening Assays, Antitumor , Cell Proliferation/drug effects , Molecular Structure , Cell Survival/drug effects , Cell Line, Tumor , Light , Density Functional Theory
16.
Org Lett ; 26(23): 4998-5003, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38838343

ABSTRACT

The direct synthesis of C4-acyl indoles deprived of C2 and C3 substituents has proven to be challenging, with scarce efficient synthetic routes being reported. Herein, we disclose a highly site-selective palladium-catalyzed C-H acylation for the construction of C4-acyl indoles via a Catellani-Lautens cyclization strategy. In addition, we systematically studied the ortho C-H acylation mechanism of iodoaniline through density functional theory (DFT) calculations and combined experimental results to elucidate the principle of high chemoselectivity brought by triazine benzoate as an acylation reagent.

17.
ArXiv ; 2024 May 27.
Article in English | MEDLINE | ID: mdl-38855549

ABSTRACT

Animals chain movements into long-lived motor strategies, exhibiting variability across scales that reflects the interplay between internal states and environmental cues. To reveal structure in such variability, we build Markov models of movement sequences that bridges across time scales and enables a quantitative comparison of behavioral phenotypes among individuals. Applied to larval zebrafish responding to diverse sensory cues, we uncover a hierarchy of long-lived motor strategies, dominated by changes in orientation distinguishing cruising versus wandering strategies. Environmental cues induce preferences along these modes at the population level: while fish cruise in the light, they wander in response to aversive stimuli, or in search for appetitive prey. As our method encodes the behavioral dynamics of each individual fish in the transitions among coarse-grained motor strategies, we use it to uncover a hierarchical structure in the phenotypic variability that reflects exploration-exploitation trade-offs. Across a wide range of sensory cues, a major source of variation among fish is driven by prior and/or immediate exposure to prey that induces exploitation phenotypes. A large degree of variability that is not explained by environmental cues unravels motivational states that override the sensory context to induce contrasting exploration-exploitation phenotypes. Altogether, by extracting the timescales of motor strategies deployed during navigation, our approach exposes structure among individuals and reveals internal states tuned by prior experience.

18.
Article in English | MEDLINE | ID: mdl-38760935

ABSTRACT

Significance: The nicotinamide adenine dinucleotide phosphate oxidase (NOX) enzyme family, located in the central nervous system, is recognized as a source of reactive oxygen species (ROS) in the brain. Despite its importance in cellular processes, excessive ROS generation leads to cell death and is involved in the pathogenesis of neurodegenerative disorders. Recent advances: NOX enzymes contribute to the development of neurodegenerative diseases, such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and stroke, highlighting their potential as targets for future therapeutic development. This review will discuss NOX's contribution and therapeutic targeting potential in neurodegenerative diseases, focusing on PD, AD, ALS, and stroke. Critical issues: Homeostatic and physiological levels of ROS are crucial for regulating several processes, such as development, memory, neuronal signaling, and vascular homeostasis. However, NOX-mediated excessive ROS generation is deeply involved in the damage of DNA, proteins, and lipids, leading to cell death in the pathogenesis of a wide range of diseases, namely neurodegenerative diseases. Future directions: It is essential to understand the role of NOX homologs in neurodegenerative disorders and the pathological mechanisms undergoing neurodegeneration mediated by increased levels of ROS. This further knowledge will allow the development of new specific NOX inhibitors and their application for neurodegenerative disease therapeutics.

19.
Ecol Lett ; 27(6): e14448, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38814285

ABSTRACT

Linking the species interactions occurring at the scale of local communities to their potential impact at evolutionary timescales is challenging. Here, we used the high-resolution fossil record of mammals from the Iberian Peninsula to reconstruct a timeseries of trophic networks spanning more than 20 million years and asked whether predator-prey interactions affected regional extinction patterns. We found that, despite small changes in species richness, trophic networks showed long-term trends, gradually losing interactions and becoming sparser towards the present. This restructuring of the ecological networks was driven by the loss of medium-sized herbivores, which reduced prey availability for predators. The decrease in prey availability was associated with predator longevity, such that predators with less available prey had greater extinction risk. These results not only reveal long-term trends in network structure but suggest that prey species richness in ecological communities may shape large scale patterns of extinction and persistence among predators.


Subject(s)
Extinction, Biological , Food Chain , Fossils , Predatory Behavior , Animals , Spain , Mammals/physiology , Carnivora/physiology , Biodiversity , Biological Evolution
20.
BMC Vet Res ; 20(1): 176, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38711127

ABSTRACT

BACKGROUND: This investigation assessed the effects of high dietary inclusion of Spirulina (Arthrospira platensis) on broiler chicken growth performance, meat quality and nutritional attributes. For this, 120 male broiler chicks were housed in 40 battery brooders (three birds per brooder). Initially, for 14 days, a standard corn and soybean meal diet was administered. Subsequently, from days 14 to 35, chicks were assigned to one of the four dietary treatments (n = 10 per treatment): (1) control diet (CTR); (2) diet with 15% Spirulina (SP); (3) diet with 15% extruded Spirulina (SPE); and (4) diet with 15% Spirulina plus a super-dosing enzymes supplement (0.20% pancreatin extract and 0.01% lysozyme) (SPM). RESULTS: Throughout the experimental period, both SP and SPM diets resulted in decreased final body weight and body weight gain compared to control (p < 0.001), with the SPE diet showing comparable results to CTR. The SPE diet prompted an increase in average daily feed intake (p = 0.026). However, all microalga treatments increased the feed conversion ratio compared to CTR. Dietary inclusion of Spirulina notably increased intestinal content viscosity (p < 0.010), which was mitigated by the SPM diet. Spirulina supplementation led to lower pH levels in breast meat 24 h post-mortem and heightened the b* colour value in both breast and thigh meats (p < 0.010). Furthermore, Spirulina contributed to an increased accumulation of total carotenoids, n-3 polyunsaturated fatty acids (PUFA), and saturated fatty acids (SFA), while diminishing n-6 PUFA, thus altering the n-6/n-3 and PUFA/SFA ratios favourably (p < 0.001). However, it also reduced zinc concentration in breast meat (p < 0.001). CONCLUSIONS: The findings indicate that high Spirulina levels in broiler diets impair growth due to increased intestinal viscosity, and that extrusion pre-treatment mitigates this effect. Despite reducing digesta viscosity, a super-dosing enzyme mix did not improve growth. Data also indicates that Spirulina enriches meat with antioxidants and n-3 PUFA but reduces α-tocopherol and increases saturated fats. Reduced zinc content in meat suggests the need for Spirulina biofortification to maintain its nutritional value.


Subject(s)
Animal Feed , Chickens , Diet , Dietary Supplements , Meat , Spirulina , Animals , Chickens/growth & development , Animal Feed/analysis , Spirulina/chemistry , Diet/veterinary , Male , Meat/analysis , Meat/standards , Animal Nutritional Physiological Phenomena/drug effects , Muramidase/metabolism
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