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1.
J Environ Sci (China) ; 149: 288-300, 2025 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39181643

RESUMEN

Structural regulation of Pd-based electrocatalytic hydrodechlorination (EHDC) catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challenging. Herein, a support electron inductive effect of Pd-Mn/Ni foam catalyst was proposed via in-situ Mn doping to optimize the electronic structure of the Ni foam (NF), which can inductive regulation of Pd for improving the EHDC performance. The mass activity and current efficiency of Pd-Mn/NF catalyst are 2.91 and 1.34 times superior to that of Pd/NF with 2,4-dichlorophenol as model compound, respectively. The Mn-doped interlayer optimized the electronic structure of Pd by bringing the d-state closer to the Fermi level than Pd on the NF surface, which optimizied the binding of EHDC intermediates. Additionally, the Mn-doped interlayer acted as a promoter for generating H* and accelerating the EHDC reaction. This work presents a simple and effective regulation strategy for constructing high-efficient cathode catalyst for the EHDC of chlorinated organic compounds.


Asunto(s)
Manganeso , Níquel , Paladio , Catálisis , Paladio/química , Manganeso/química , Níquel/química , Técnicas Electroquímicas/métodos , Electrodos , Clorofenoles/química , Halogenación
2.
Food Chem ; 462: 140975, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39197240

RESUMEN

This study isolated a novel peptide MMGGED with strong calcium-binding capacity from defatted walnut meal and synthesized a novel peptide­calcium chelate COS-MMGGED-Ca with high stability via glycation. Structural characterization and computer simulation identified binding sites, while in vitro digestion stability and calcium transport experiments explored the chelate's properties. Results showed that after glycation, COS-MMGGED bound Ca2+ with 88.75 ± 1.75 %, mainly via aspartic and glutamic acids. COS-MMGGED-Ca released Ca2+ steadily (60.27 %), with thermal denaturation temperature increased by 18 °C and 37 °C compared to MMGGED-Ca, indicating good processing performance. Furthermore, COS-MMGGED significantly enhanced Ca2+ transport across Caco-2 monolayers, 1.13-fold and 1.62-fold higher than CaCl2 and MMGGED, respectively, at 240 h. These findings prove glycation enhances structural properties, stability, calcium loading, and transport of peptide­calcium chelates, providing a scientific basis for developing novel efficient calcium supplements and high-value utilization of walnut meal.


Asunto(s)
Calcio , Juglans , Péptidos , Juglans/química , Humanos , Calcio/química , Calcio/metabolismo , Células CACO-2 , Péptidos/química , Péptidos/metabolismo , Glicosilación , Quelantes del Calcio/química
3.
Food Chem ; 462: 140996, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39213962

RESUMEN

The mechanisms of trypsin hydrolysis time on the structure of soy protein hydrolysate fibril aggregates (SPHFAs) and the stability of SPHFAs-high internal phase Pickering emulsions (HIPPEs) were investigated. SPHFAs were prepared using soy protein hydrolysate (SPH) with different trypsin hydrolysis time (0 min-120 min) to stabilize SPHFAs-HIPPEs. The results showed that moderate trypsin hydrolysis (30 min, hydrolysis degree of 2.31 %) induced SPH unfolding and increased the surface hydrophobicity of SPH, thereby promoting the formation of flexible SPHFAs with maximal thioflavin T intensity and ζ-potential. Moreover, moderate trypsin hydrolysis improved the viscoelasticity of SPHFAs-HIPPEs, and SPHFAs-HIPPEs remained stable after storage at 25 °C for 80 d and heating at 100 °C for 1 h. Excessive trypsin hydrolysis (> 30 min) decreased the stability of SPHFAs-HIPPEs. In conclusion, moderate trypsin hydrolysis promoted the formation of flexible SPHFAs with high surface charge by inducing SPH unfolding, thereby promoting the stability of SPHFAs-HIPPEs.


Asunto(s)
Emulsiones , Interacciones Hidrofóbicas e Hidrofílicas , Hidrolisados de Proteína , Proteínas de Soja , Tripsina , Tripsina/química , Hidrólisis , Emulsiones/química , Proteínas de Soja/química , Hidrolisados de Proteína/química , Agregado de Proteínas
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124943, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39146629

RESUMEN

The use of a conjugate N-containing ligand resulted in the decreasing of structural dimensions from 2D network of [Tb(2-pyia)(Ac)(H2O)] (CP1) to 1D chain [Tb(2-pyia)(Ac)(IDP)] (CP2) (2-H2pyia = 5-(pyridin-2-ylmethoxy) isophthalic acid and IDP=imidazo[4,5-f]-[1,10] phenanthroline). Both of them exhibit the characteristic luminescence of Tb ions and could have high fluorescence sensing properties for cefixime and fluridine. The different sensing properties for nitro explosives are manifested as CP1 for nitrobenzene and CP2 for 4-nitrophenol due to the difference in structure. Furthermore, CP2 exhibits the ratiometric fluorescence sensing for Fe3+ ion with a low detection limit of 0.405 µM. The fluorescence sensing mechanism of the two Tb complexes for different analytes was investigated using experimental methods and theoretical calculations. CP1 was used for the detection of Flu residues in the actual system and better results were obtained. The work shows the introduction of the chelated ligand might affect the structural and sensing performance changes of coordination polymers.

5.
J Environ Sci (China) ; 148: 375-386, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095172

RESUMEN

Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River-which is the longest river in China. As phytoplankton are sensitive indicators of trophic changes in water bodies, characterizing phytoplankton communities and their growth influencing factors in polluted urban rivers can provide new ideas for pollution control. Here, we used direct microscopic count and environmental DNA (eDNA) metabarcoding methods to investigate phytoplankton community structure in Tuojiang River Basin (Chengdu, Sichuan Province, China). The association between phytoplankton community structure and water environmental factors was evaluated by Mantel analysis. Additional environmental monitoring data were used to pinpoint major factors that influenced phytoplankton growth based on structural equation modeling. At the phylum level, the dominant phytoplankton taxa identified by the conventional microscopic method mainly belonged to Bacillariophyta, Chlorophyta, and Cyanophyta, in contrast with Chlorophyta, Dinophyceae, and Bacillariophyta identified by eDNA metabarcoding. In α-diversity analysis, eDNA metabarcoding detected greater species diversity and achieved higher precision than the microscopic method. Phytoplankton growth was largely limited by phosphorus based on the nitrogen-to-phosphorus ratios > 16:1 in all water samples. Redundancy analysis and structural equation modeling also confirmed that the nitrogen-to-phosphorus ratio was the principal factor influencing phytoplankton growth. The results could be useful for implementing comprehensive management of the river basin environment. It is recommended to control the discharge of point- and surface-source pollutants and the concentration of dissolved oxygen in areas with excessive nutrients (e.g., Jianyang-Ziyang). Algae monitoring techniques and removal strategies should be improved in 201 Hospital, Hongrihe Bridge and Colmar Town areas.


Asunto(s)
Monitoreo del Ambiente , Fitoplancton , Ríos , Ríos/química , China , Contaminantes Químicos del Agua/análisis , Fósforo/análisis
6.
Mar Life Sci Technol ; 6(3): 425-441, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39219675

RESUMEN

The aquatic plant Nymphaea, a model genus of the early flowering plant lineage Nymphaeales and family Nymphaeaceae, has been extensively studied. However, the availability of chloroplast genome data for this genus is incomplete, and phylogenetic relationships within the order Nymphaeales remain controversial. In this study, 12 chloroplast genomes of Nymphaea were assembled and analyzed for the first time. These genomes were 158,290-160,042 bp in size and contained 113 non-repeat genes, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. We also report on codon usage, RNA editing sites, microsatellite structures, and new repetitive sequences in this genus. Comparative genomics revealed that expansion and contraction of IR regions can lead to changes in the gene numbers. Additionally, it was observed that the highly variable regions of the chloroplast genome were mainly located in intergenic regions. Furthermore, the phylogenetic tree showed the order Nymphaeales was divided into three families, and the genus Nymphaea can be divided into five (or three) subgenera, with the subgenus Nymphaea being the oldest. The divergence times of nymphaealean taxa were analyzed, with origins of the order Nymphaeales and family Nymphaeaceae being about 194 and 131 million years, respectively. The results of the phylogenetic analysis and estimated divergence times will be useful for future evolutionary studies of basal angiosperm lineages. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-024-00242-0.

7.
Iran J Biotechnol ; 22(2): e3787, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39220333

RESUMEN

Background: In-silico analysis provides a fast, simple, and cost-free method for identifying potentially pathogenic single nucleotide variants. Objective: To propose a simple and relatively fast method for the prediction of variant pathogenicity using free online in-silico (IS) tools with AURKA gene as a model. Materials and Methods: We aim to propose a methodology to predict variants with high pathogenic potential using computational analysis, using AURKA gene as model. We predicted a protein model and analyzed 209 out of 64,369 AURKA variants obtained from Ensembl database. We used bioinformatic tools to predict pathogenicity. The results were compared through the VarSome website, which includes its own pathogenicity score and the American College of Medical Genetics (ACMG) classification. Results: Out of the 209 analyzed variants, 16 were considered pathogenic, and 13 were located in the catalytic domain. The most frequent protein changes were size and hydrophobicity modifications of amino acids. Proline and Glycine amino acid substitutions were the most frequent changes predicted as pathogenic. These bioinformatic tools predicted functional changes, such as protein up or down-regulation, gain or loss of molecule interactions, and structural protein modifications. When compared to the ACMG classification, 10 out of 16 variants were considered likely pathogenic, with 7 out of 10 changes at Proline/Glycine substitutions. Conclusion: This method allows quick and cost-free bulk variant screening to identify variants with pathogenic potential for further association and/or functional studies.

8.
Heliyon ; 10(16): e35769, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39220924

RESUMEN

Angiogenesis is an essential process in tumorigenesis, tumor invasion, and metastasis, and is an intriguing pathway for drug discovery. Targeting vascular endothelial growth factor receptor 2 (VEGFR2) to inhibit tumor angiogenic pathways has been widely explored and adopted in clinical practice. However, most drugs, such as the Food and Drug Administration -approved drug axitinib (ATC code: L01EK01), have considerable side effects and limited tolerability. Therefore, there is an urgent need for the development of novel VEGFR2 inhibitors. In this study, we propose a novel strategy to design potential candidates targeting VEGFR2 using three-dimensional (3D) deep learning and structural modeling methods. A geometric-enhanced molecular representation learning method (GEM) model employing a graph neural network (GNN) as its underlying predictive algorithm was used to predict the activity of the candidates. In the structural modeling method, flexible docking was performed to screen data with high affinity and explore the mechanism of the inhibitors. Small -molecule compounds with consistently improved properties were identified based on the intersection of the scores obtained from both methods. Candidates identified using the GEM-GNN model were selected for in silico modeling using molecular dynamics simulations to further validate their efficacy. The GEM-GNN model enabled the identification of candidate compounds with potentially more favorable properties than the existing drug, axitinib, while achieving higher efficacy.

9.
Front Neurosci ; 18: 1385847, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221005

RESUMEN

Diffusion-weighted imaging (DWI) is the primary method to investigate macro- and microstructure of neural white matter in vivo. DWI can be used to identify and characterize individual-specific white matter bundles, enabling precise analyses on hypothesis-driven connections in the brain and bridging the relationships between brain structure, function, and behavior. However, cortical endpoints of bundles may span larger areas than what a researcher is interested in, challenging presumptions that bundles are specifically tied to certain brain functions. Functional MRI (fMRI) can be integrated to further refine bundles such that they are restricted to functionally-defined cortical regions. Analyzing properties of these Functional Sub-Bundles (FSuB) increases precision and interpretability of results when studying neural connections supporting specific tasks. Several parameters of DWI and fMRI analyses, ranging from data acquisition to processing, can impact the efficacy of integrating functional and diffusion MRI. Here, we discuss the applications of the FSuB approach, suggest best practices for acquiring and processing neuroimaging data towards this end, and introduce the FSuB-Extractor, a flexible open-source software for creating FSuBs. We demonstrate our processing code and the FSuB-Extractor on an openly-available dataset, the Natural Scenes Dataset.

10.
Front Pharmacol ; 15: 1421662, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221141

RESUMEN

Eucommia ulmoides (EU) is a precious tree species native to China originating during the ice age. This species has important economic value and comprehensive development potential, particularly in medicinal applications. The medicinal parts of EU are its bark (Eucommiae cortex) and leaves (Eucommiae folium) which have been successively used as a traditional Chinese medicine to treat diseases since the first century BC. During the last 2 decades, as natural polysaccharides have become of increasing interest in pharmacology, biomedicine, cosmetic and food applications, more and more scholars have begun to study polysaccharides derived from EU as well. EU polysaccharides have been found to have a variety of biological functions both in vivo and in vitro, including immunomodulatory, antioxidant, anti-inflammatory, anticomplementary, antifatigue, and hepatoprotective activities. This review aims to summarize these recent advances in extraction, purification, structural characteristics, pharmacological activities and applications in different fields of EU bark and leaf polysaccharides. It was found that both Eucommiae folium polysaccharides and Eucommiae cortex polysaccharides were suitable for medicinal use. Eucommiae folium may potentially be used to substitute for Eucommiae cortex in terms of immunomodulation and antioxidant activities. This study serves as a valuable reference for improving the comprehensive utilization of EU polysaccharides and further promoting the application of EU polysaccharides.

11.
Autism Dev Lang Impair ; 9: 23969415241275931, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221433

RESUMEN

The current diagnostic criteria for the autism spectrum disorder (ASD) include the possibility to specify concomitant language difficulties. Purpose: Our main aim was to explore whether children with ASD-Level 1 (ASD-L1) present difficulties in the acquisition of structural language, as little work has been done in this regard so far. As a secondary aim we evaluated the degree to which the potential language impairment in ASD is directly associated with their social communication deficits or it represents a distinct deficit. Methods: To further clarify the nature and characteristics of putative language difficulties in ASD-L1, we evaluated language skills in 89 children and preadolescents diagnosed with ASD-L1, and a group of typically developing participants (TD). All of them were between 8 and 13 years old and had similar socioeconomic backgrounds. Results: Children with ASD-L1 obtained lower scores than those in TD group in repeating sentences, in finding the semantic relationships between words, and in applying word structure rules (morphology). Congruently, the core language standard score was lower in the ASD-L1 group, and the proportion of language delay was significantly higher in the ASD-L1 group than in the control group. Conclusion: Language scores were associated with autistic traits; thus, language performance in ASD-L1 is closely related to autistic symptoms. These results are discussed according to the literature on linguistic deficits in ASD-L1 and their relations with phonological working memory.

12.
Microsc Res Tech ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39222385

RESUMEN

Three different crystal morphologies of α-Fe2O3, including uniform hexagonal, square, and rhombic shapes, were prepared according to the aqueous-thermal reaction. The hexagonal-shaped α-Fe2O3 was enclosed by the 104 plane, while the square and rhombic structures were enclosed by the 110 plane. Two absorption peaks at 455 and 532 cm-1 were found for the perpendicular (⊥) modes, and one absorption peak at 650 cm-1 appeared for the parallel (||) mode for hexagon-shaped α-Fe2O3 during analysis by Fourier-transform infrared spectroscopy. However, the peaks of square- and rhombic-shaped α-Fe2O3 for perpendicular (⊥) mode blueshifted, and the former two peaks merged together forming a broad band at approximately 480 cm-1. For Raman spectra determination, the peaks arose from the Brillouin zone center, and two additional peaks were observed at 660 and 1320 cm-1, belonging to 1 longitudinal optical (1LO) and 2 longitudinal optical (2LO) modes. All three materials exhibited higher intensities when excited at a wavelength of 633 cm-1. Furthermore, in the polarization state, the centers of all peak positions slightly shifted for hexagon-shaped α-Fe2O3, but all peak positions for square-shaped and rhombic-shaped α-Fe2O3 exhibited a significant blueshift. The structure of hexagon-shaped α-Fe2O3 was relatively tolerant regarding the polarization properties of vibration modes; however, the symmetry of crystal square-shaped and rhombic-shaped α-Fe2O3 changed, subsequently revealing different optical properties. RESEARCH HIGHLIGHTS: The hexagon-shaped, square-shaped, and rhombic-shaped α-Fe2O3 enclosed by different planes were synthesized. The Fourier Transform Infrared spectrometer peaks of α-Fe2O3 depended on their hexagon, square and rhombic shapes. Compared with hexagon-shaped α-Fe2O3, the Raman peaks for square and rhombi ones significantly shifted. The hexagon-shaped α-Fe2O3 is relatively tolerant regarding the polarization properties.

13.
Biochem Biophys Res Commun ; 734: 150613, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39222577

RESUMEN

The native conformation of a protein plays a decisive role in ensuring its functionality. It is established that the spatial structure of proteins may exhibit a greater degree of conservation than the corresponding amino acid sequences. This study aims to clarify structural distinctions between homologous and non-homologous proteins with identical topology. The analysis focuses on secondary structures with special emphasis on their fraction, distribution along the polypeptide chain, and chirality. Three different groups of proteins with identical topology were considered according to the CATH database: a homologous group of Globins, a group of Phycocyanins, which is often considered as a potential relative of globins, and a diverse assembly of other globin-like proteins. Some structural patterns in the distribution of secondary structure have been identified within Globins. A similar profile was observed in Phycocyanins, in contrast to the third group. In addition, a distinguishable structural motif, including structures such as 310-helix and irregular structure, has been found in both Globins and Phycocyanins, which can be proposed as an evolutionary imprint.

14.
Enzymes ; 55: 93-120, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39223000

RESUMEN

Carbonic anhydrases (CAs) are a ubiquitous family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide to bicarbonate and protons, playing pivotal roles in a variety of biological processes including respiration, calcification, acid-base balance, and CO2 fixation. Recent studies have expanded the understanding of CAs, particularly the γ-class from diverse biological sources such as pathogenic bacteria, extremophiles, and halophiles, revealing their unique structural adaptations and functional mechanisms that enable operation under extreme environmental conditions. This chapter discusses the comprehensive catalytic mechanism and structural insights from X-ray crystallography studies, highlighting the molecular adaptations that confer stability and activity to these enzymes in harsh environments. It also explores the modulation mechanism of these enzymes, detailing how different modulators interact with the active site of γ-CAs. Comparative analyzes with other CA classes elucidate the evolutionary trajectories and functional diversifications of these enzymes. The synthesis of this knowledge not only sheds light on the fundamental aspects of CA biology but also opens new avenues for therapeutic and industrial applications, particularly in designing targeted inhibitors for pathogenic bacteria and developing biocatalysts for industrial processes under extreme conditions. The continuous advancement in structural biology promises further insights into this enzyme family, potentially leading to novel applications in medical and environmental biotechnology.


Asunto(s)
Bacterias , Anhidrasas Carbónicas , Anhidrasas Carbónicas/metabolismo , Anhidrasas Carbónicas/química , Bacterias/enzimología , Bacterias/efectos de los fármacos , Dominio Catalítico , Cristalografía por Rayos X , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Dióxido de Carbono/metabolismo , Dióxido de Carbono/química
15.
Small ; : e2405950, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39224048

RESUMEN

Ultralight graphene aerogels with high electrical conductivity and superelasticity are demanded yet difficult to produce. A versatile emulsion-based approach is demonstrate to optimize multiscale structure of lightweight, elastic, and conductive graphene aerogels. By constructing Pickering emulsion using graphene oxide (GO), poly (amic acid) (PAA), and octadeyl amine (ODA), micron-level close-pore structure is realized while thermal shrinkage mismatch between GO and PAA creates numerous nanowrinkles during thermal annealing. GO nanosheets are bridged by PAA-derived carbon, enhancing the structural integrity at molecular level. These multiscale structural features facilitate rapid electron transport and efficient load transfer, conferring graphene aerogels with intriguing mechanical and electromagnetic interference (EMI) shielding properties. The emulsion-based graphene aerogel with an ultralow density of ≈3.0 mg cm-3 integrates outstanding electrical conductivity, air-caliber thermal insulation, high EMI shielding effectiveness of 75.0 dB, and 90% strain compressibility with superb fatigue resistance. Intriguingly, thanks to the gel-like rheological behavior of the emulsion, ultralight graphene scaffolds with programmable geometries are obtained by 3D printing. This work provides a general approach for the preparation of ultralight and superelastic graphene aerogels with excellent EMI shielding properties, showing broad application prospects in various fields.

16.
Conserv Biol ; : e14364, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225252

RESUMEN

Anthropogenic activities may alter felid assemblage structure, facilitating the persistence of tolerant species (commonly mesopredators), excluding ecologically demanding ones (top predators) and, consequently, changing coexistence rules. We aimed to determine how human activities influence intraguild relationships among top predators and their cascading effects on mesopredators, which remain poorly understood despite evidence of top carnivore decline. We used structural equation modeling at a continental scale to investigate how habitat quality and quantity, livestock density, and other human pressures modified the intraguild relations of the 3 species that are at the top of the food chain in the Neotropics: jaguars (Panthera onca), pumas (Puma concolor), and ocelots (Leopardus pardalis). We included presence-absence data derived from systematic studies compiled in Neocarnivores data set for these felid species at 0.0833° resolution. Human disturbance reduced the probability of jaguar occurrence by -0.35 standard deviations. Unexpectedly, the presence of sheep (Ovis aries) or goats (Capra aegagrus hircus) and jaguars was positively related to the presence of pumas, whereas puma presence was negatively related to the presence of ocelots. Extent of forest cover had more of an effect on jaguar (ß = 0.23) and ocelot (ß = 0.12) occurrences than the extent of protected area, which did not have a significant effect. The lack of effect of human activities on puma presence and the positive effect of small livestock supports the notion that pumas are more adaptable to habitat disturbance than jaguars. Our findings suggest that human disturbance has the potential to reverse the hierarchical competition dominance among large felids, leading to an unbalanced community structure. This shift disadvantages jaguars and elevates the position of pumas in the assemblage hierarchy, resulting in the exclusion of ocelots, despite their relatively lower susceptibility to anthropogenic disturbance. Our results suggest that conservation efforts should extend beyond protected areas to encompass the surrounding landscape, where complexities and potential conflicts are more pronounced.


Efectos de la tolerancia dispareja a las perturbaciones humanas sobre las interacciones de dominancia de los depredadores mayores Resumen Las actividades antropogénicas pueden alterar la estructura de las poblaciones de félidos, lo que facilita la persistencia de especies tolerantes (normalmente mesodepredadores), excluye a otras especies con exigencias ecológicas (depredadores mayores) y, en consecuencia, modifica las reglas de coexistencia. Buscamos determinar cómo influyen las actividades humanas sobre las relaciones entre gremios de los depredadores superiores y sus efectos en cascada sobre los mesodepredadores, que aún son poco conocidos a pesar de las pruebas del declive de los carnívoros superiores. Utilizamos modelos de ecuaciones estructurales a escala continental para investigar cómo la calidad y cantidad del hábitat, la densidad ganadera y otras presiones humanas modifican las relaciones entre gremios de las tres especies que se encuentran en la cima de la cadena trófica en el Neotrópico: jaguares (Panthera onca), pumas (Puma concolor) y ocelotes (Leopardus pardalis). Incluimos datos de presencia­ausencia derivados de estudios sistemáticos recopilados en el conjunto de datos Neocarnivores para estas especies de félidos con una resolución de 0.0833°. Las perturbaciones humanas redujeron la probabilidad de aparición del jaguar en ­0.35 desviaciones estándar. De forma inesperada, la presencia de ovejas (Ovis aries) o cabras (Capra aegargrus hircus) y jaguares tuvo una relación positiva con la presencia de pumas, mientras que la presencia de pumas tuvo una relación negativa con la presencia de ocelotes. La extensión de la cubierta forestal tuvo más efecto sobre la presencia de jaguares (ß = 0.23) y ocelotes (ß = 0.12) que la extensión del área protegida, que no tuvo un efecto significativo. La falta de efectos de las actividades humanas sobre la presencia del puma y el efecto positivo del ganado menor apoyan la idea de que los pumas son más adaptables a las perturbaciones del hábitat que los jaguares. Nuestros hallazgos sugieren que las perturbaciones humanas tienen el potencial de invertir la dominancia jerárquica de competencia entre los grandes félidos, lo que lleva a una estructura comunitaria desequilibrada. Este cambio perjudica a los jaguares y eleva la posición de los pumas en la jerarquía del ensamblaje, lo que excluye a los ocelotes, a pesar de su relativamente menor susceptibilidad a las perturbaciones antropogénicas. Nuestros resultados sugieren que los esfuerzos de conservación deberían extenderse más allá de las áreas protegidas para abarcar el paisaje circundante, donde las complejidades y los conflictos potenciales son más pronunciados.

17.
Adv Sci (Weinh) ; : e2405200, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225461

RESUMEN

Quetiapine myristate (QM), an ester-bonded lipophilic prodrug of quetiapine (QTP), is synthesized and converted into an amphiphilic structure in acidic pH to trigger a novel self-assembled QM nanosuspension (QMN). Following injection, this QMN rearranges within physiological pH to form nanoaggregates in structure, resulting in enhanced physicochemical properties and in vivo therapeutic performance without an initial burst release. The 200-nm-sized QMN exhibits less invasive injection, higher drug content, and better storage stability profile than conventional poly(lactide-co-glycolide) (PLGA) nanosuspensions containing QTP or QM. Following a single intramuscular injection to beagle dogs (35 mg kg-1 QTP), QMN undergoes pH-responsive nanoaggregation to form the lipophilic prodrug, providing esterase-oriented sustained release for five weeks compared with the two-week period of PLGA nanosuspensions. Notably, QMN exhibits improved in vivo pharmacokinetic performance with long-acting delivery while minimizing issues associated with polymeric PLGA formulations, including the initial massive burst release, cellular toxicity, and adverse side effects. These results support the further development of QMN as a novel long-acting injectable to improve patient compliance and dosing frequency.

18.
Protein Expr Purif ; 226: 106604, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243999

RESUMEN

The L-isoleucine-4-dioxygenase converts L-isoleucine (Ile) into(2S,3R,4S)-4-(OH)-isoleucine (4-HIL), a naturally occurring hydroxyl amino acid, which is a promising compound for drug and functional food development. Here, a novel L-isoleucine-4-dioxygenase (RaIDO) from Rahnella aquatilis was cloned, expressed and characterized, as one of only a few reported L-isoleucine-4-dioxygenases. RaIDO showed high catalytic efficiency with Ile as the substrate, as well as good stability. HPLC-MS and NMR confirmed that RaIDO converts Ile into (2S,3R,4S)-4-(OH)-isoleucine. Further, structural analysis of RaIDO revealed key active site residues, including H159, D161 and H212. The RaIDO enzyme showed an optimal reaction temperature range of 30°C-45 °C, with the highest catalytic activity observed at 40 °C. Additionally, the enzyme exhibited an optimal pH of 8.0. Thus, the novel L-isoleucine-4-dioxygenase (RaIDO) has high catalytic efficiency and good stability, making it a strong candidate for industrial applications.

19.
Int J Biol Macromol ; 279(Pt 3): 135407, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245108

RESUMEN

Two polysaccharides, PGP-90 and PGP-100 (molecular weights of 7.59 × 102 kDa and 10.48 × 102 kDa, respectively), were isolated from Peach gum using alkaline electrolyte water as an extraction solution. Structural characterization showed that PGP-90 and PGP-100 are AG-II arabinogalactans with ß-D-(1 â†’ 6)-Galp as the main chain and 1 â†’ 3 Araf and 1 â†’ 5 Araf branched chains at O-3 and O-4 positions. Animal experiments showed that PGP-90 and PGP-100 significantly improved immune function, enhance the proliferative capacity of lymphocytes and phagocytosis of peritoneal macrophages, and regulated the ratio of lymphocyte subpopulations in S180 tumor-bearing mice. Meanwhile, PGP-90 and PGP-100 promoted the secretion of cytokines (TNF-α, IFN-γ, and IL-2) by activated macrophages and blocked apoptosis at the G1 phase, resulting in tumor suppression rates of 40.80 % and 46.30 % (100 mg/kg), respectively, with PGP-100 demonstrating stronger in vivo anti-tumor activity. The above experimental results indicate that Peach gum polysaccharides have the potential to be functional anti-tumor agents.

20.
Gigascience ; 132024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-39250077

RESUMEN

More people in the world depend on water buffalo for their livelihoods than on any other domesticated animals, but its genetics is still not extensively explored. The 1000 Buffalo Genomes Project (1000BGP) provides genetic resources for global buffalo population study and tools to breed more sustainable and productive buffaloes. Here we report the most contiguous swamp buffalo genome assembly (PCC_UOA_SB_1v2) with substantial resolution of telomeric and centromeric repeats, ∼4-fold more contiguous than the existing reference river buffalo assembly and exceeding a recently published male swamp buffalo genome. This assembly was used along with the current reference to align 140 water buffalo short-read sequences and produce a public genetic resource with an average of ∼41 million single nucleotide polymorphisms per swamp and river buffalo genome. Comparison of the swamp and river buffalo sequences showed ∼1.5% genetic differences, and estimated divergence time occurred 3.1 million years ago (95% CI, 2.6-4.9). The open science model employed in the 1000BGP provides a key genomic resource and tools for a species with global economic relevance.


Asunto(s)
Búfalos , Variación Genética , Genoma , Polimorfismo de Nucleótido Simple , Búfalos/genética , Animales , Ríos , Genómica/métodos , Filogenia
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