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1.
Brain Res ; 1841: 149086, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38876319

RESUMEN

Alcohol use disorder (AUD) remains a critical public health issue worldwide, characterized by high relapse rates often triggered by contextual cues. This research investigates the neural mechanisms behind context-induced reinstatement of alcohol-seeking behavior, focusing on the nucleus accumbens and its interactions with the prelimbic cortex, employing Male Long-Evans rats in an ABA renewal model. In our experimental setup, rats were trained to self-administer 10 % ethanol in Context A, followed by extinction of lever pressing in the presence of discrete cues in Context B. The context-induced reinstatement of ethanol-seeking was then assessed by re-exposing rats to Context A or B under extinction conditions, aiming to simulate the environmental cues' influence on relapse behaviors. Three experiments were conducted: Experiment 1 utilized Fos-immunohistochemistry to examine neuronal activation in the nucleus accumbens; Experiment 2 applied the baclofen + muscimol inactivation technique to probe the functional importance of the nucleus accumbens core; Experiment 3 used Fos-immunofluorescence along with Retrobeads injection to investigate activation of neurons projecting from the prelimbic cortex to the nucleus accumbens core. Our findings revealed significant increases in Fos-immunoreactive nuclei within the nucleus accumbens core and shell during the reinstatement phase in Context A, underscoring the environment's potent effect on ethanol-seeking behavior. Additionally, inactivation of the nucleus accumbens core markedly reduced reinstatement, and there was a notable activation of neurons from the prelimbic cortex to the nucleus accumbens core in the ethanol-associated context. These results highlight the critical role of the nucleus accumbens core and its corticostriatal projections in the neural circuitry underlying context-driven ethanol seeking.

2.
PLoS One ; 19(5): e0303612, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38820505

RESUMEN

Obesity, a burgeoning global health crisis, has tripled in prevalence over the past 45 years, necessitating innovative research methodologies. Adipocytes, which are responsible for energy storage, play a central role in obesity. However, most studies in this field rely on animal models or adipocyte monolayer cell cultures, which are limited in their ability to fully mimic the complex physiology of a living organism, or pose challenges in terms of cost, time consumption, and ethical considerations. These limitations prompt a shift towards alternative methodologies. In response, here we show a 3D in vitro model utilizing the 3T3-L1 cell line, aimed at faithfully replicating the metabolic intricacies of adipocytes in vivo. Using a workable cell line (3T3-L1), we produced adipocyte spheroids and differentiated them in presence and absence of TNF-α. Through a meticulous proteomic analysis, we compared the molecular profile of our adipose spheroids with that of adipose tissue from lean and obese C57BL/6J mice. This comparison demonstrated the model's efficacy in studying metabolic conditions, with TNF-α treated spheroids displaying a notable resemblance to obese white adipose tissue. Our findings underscore the model's simplicity, reproducibility, and cost-effectiveness, positioning it as a robust tool for authentically mimicking in vitro metabolic features of real adipose tissue. Notably, our model encapsulates key aspects of obesity, including insulin resistance and an obesity profile. This innovative approach has the potential to significantly impact the discovery of novel therapeutic interventions for metabolic syndrome and obesity. By providing a nuanced understanding of metabolic conditions, our 3D model stands as a transformative contribution to in vitro research, offering a pathway for the development of small molecules and biologics targeting these pervasive health issues in humans.


Asunto(s)
Células 3T3-L1 , Adipocitos , Obesidad , Esferoides Celulares , Animales , Ratones , Obesidad/metabolismo , Adipocitos/metabolismo , Adipocitos/citología , Esferoides Celulares/metabolismo , Ratones Endogámicos C57BL , Redes y Vías Metabólicas , Diferenciación Celular , Factor de Necrosis Tumoral alfa/metabolismo , Proteómica/métodos
3.
J Dent ; 146: 105073, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38782176

RESUMEN

OBJECTIVES: Evaluate, in vitro, the effect of incorporating nano-sized sodium trimetaphosphate (TMPnano) and phosphorylated chitosan (Chi-Ph) into resin-modified glass ionomer cement (RMGIC) used for orthodontic bracket cementation, on mechanical, fluoride release, antimicrobial and cytotoxic properties. METHODS: RMGIC was combined with Chi-Ph (0.25%/0.5%) and/or TMPnano (14%). The diametral compressive/tensile strength (DCS/TS), surface hardness (SH) and degree of conversion (%DC) were determined. For fluoride (F) release, samples were immersed in des/remineralizing solutions. Antimicrobial/antibiofilm activity was evaluated by the agar diffusion test and biofilm metabolism (XTT). Cytotoxicity in fibroblasts was assessed with the resazurin method. RESULTS: After 24 h, the RMGIC-14%TMPnano group showed a lower TS value (p < 0.001); after 7 days the RMGIC-14%TMPnano-0.25%Chi-Ph group showed the highest value (p < 0.001). For DCS, the RMGIC group (24 h) showed the highest value (p < 0.001); after 7 days, the highest value was observed for the RMGIC-14%TMPnano-0.25%Chi-Ph (p < 0.001). RMGIC-14%TMPnano, RMGIC-14%TMPnano-0.25%Chi-Ph, RMGIC-14%TMPnano-0.5%Chi-Ph showed higher and similar release of F (p > 0.001). In the SH, the RMGIC-0.25%Chi-Ph; RMGIC-0.5%Chi-Ph; RMGIC-14%TMPnano-0.5%Chi-Ph groups showed similar results after 7 days (p > 0.001). The RMGIC-14%TMPnano-0.25%Chi-Ph group showed a better effect on microbial/antibiofilm growth, and the highest efficacy on cell viability (p < 0.001). After 72 h, only the RMGIC-14%TMPnano-0.25%Chi-Ph group showed cell viability (p < 0.001). CONCLUSION: The RMGIC-14%TMPnano-0.25%Chi-Ph did not alter the physical-mechanical properties, was not toxic to fibroblasts and reduced the viability and metabolism of S. mutans. CLINICAL RELEVANCE: The addition of phosphorylated chitosan and organic phosphate to RMGIC could provide an antibiofilm and remineralizing effect on the tooth enamel of orthodontic patients, who are prone to a high cariogenic challenge due to fluctuations in oral pH and progression of carious lesions.


Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Fibroblastos , Fluoruros , Cementos de Ionómero Vítreo , Ensayo de Materiales , Quitosano/farmacología , Antibacterianos/farmacología , Cementos de Ionómero Vítreo/farmacología , Cementos de Ionómero Vítreo/química , Biopelículas/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fosforilación , Fluoruros/farmacología , Dureza , Resistencia a la Tracción , Propiedades de Superficie , Fuerza Compresiva , Nanopartículas , Cementos de Resina/química , Polifosfatos/farmacología , Cementos Dentales/farmacología , Cementos Dentales/química , Supervivencia Celular/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Animales , Fosfatos/farmacología , Humanos , Soportes Ortodóncicos
4.
Artículo en Inglés | MEDLINE | ID: mdl-38803175

RESUMEN

BACKGROUND: Distillery vinasse is one of the promising bio-fertilizers, as it contains significant amounts of essential chemical elements, allied with sorghum that is widely used in the diet of ruminant animals and has been considered as an alternative to the production of other cereals or forages. This study aimed to evaluate saccharin sorghum silage from fertilization with vinasse. METHODS: The research was conducted using the BRS-511, CR-1339, and CR-1342 geno-types. The silage was held for 170 days after sowing, with experimental design in blocks with triple factorial (genotypes x fertilization x inoculation) totaling 54 installments. At 95 days, the silos were opened for sample collection and analysis bromatological analysis. RESULTS: The results indicate the primary source of variation was genotype, characterizing them with different potentials in productivity and better results for BRS-511, CR-1339, and CR-1342. The bromatological results indicate good quality for CR-1339 and CR-1342 hybrids, however, better digestability for BRS-511. There was no observable difference between the factors of fertilization. The inoculation additive assists in the reduction of lignin appears to be high. PCA analysis showed differences between cultivars (BRS-511, CR-1339, and CR-1342) and fertili-zation. However, the PCAs showed the genotypes show similar results with conventional ferti-lization and sugarcane vinasse. CONCLUSION: The study reflected the possibility of producing sweet sorghum silage with soil sugarcane vinasse fertilization as fertilizer.

5.
ACS Pharmacol Transl Sci ; 7(5): 1637-1649, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38751615

RESUMEN

Nitrocatechols are the standard pharmacophore to develop potent tight-binding inhibitors of catechol O-methyltransferase (COMT), which can be used as coadjuvant drugs to manage Parkinson's disease. Tolcapone is the most potent drug of this class, but it has raised safety concerns due to its potential to induce liver damage. Tolcapone-induced hepatotoxicity has been attributed to the nitrocatechol moiety; however, other nitrocatechol-based COMT inhibitors, such as entacapone, are safe and do not damage the liver. There is a knowledge gap concerning which mechanisms and chemical properties govern the toxicity of nitrocatechol-based COMT inhibitors. Using a vast array of cell-based assays, we found that tolcapone-induced toxicity is caused by direct interference with mitochondria that does not depend on bioactivation by P450. Our findings also suggest that (a) lipophilicity is a key property in the toxic potential of nitrocatechols; (b) the presence of a carbonyl group directly attached to the nitrocatechol ring seems to increase the reactivity of the molecule, and (c) the presence of cyano moiety in double bond stabilizes the reactivity decreasing the cytotoxicity. Altogether, the fine balance between lipophilicity and the chemical nature of the C1 substituents of the nitrocatechol ring may explain the difference in the toxicological behavior observed between tolcapone and entacapone.

6.
bioRxiv ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38712216

RESUMEN

Deep learning methods, trained on the increasing set of available protein 3D structures and sequences, have substantially impacted the protein modeling and design field. These advancements have facilitated the creation of novel proteins, or the optimization of existing ones designed for specific functions, such as binding a target protein. Despite the demonstrated potential of such approaches in designing general protein binders, their application in designing immunotherapeutics remains relatively unexplored. A relevant application is the design of T cell receptors (TCRs). Given the crucial role of T cells in mediating immune responses, redirecting these cells to tumor or infected target cells through the engineering of TCRs has shown promising results in treating diseases, especially cancer. However, the computational design of TCR interactions presents challenges for current physics-based methods, particularly due to the unique natural characteristics of these interfaces, such as low affinity and cross-reactivity. For this reason, in this study, we explored the potential of two structure-based deep learning protein design methods, ProteinMPNN and ESM-IF, in designing fixed-backbone TCRs for binding target antigenic peptides presented by the MHC through different design scenarios. To evaluate TCR designs, we employed a comprehensive set of sequence- and structure-based metrics, highlighting the benefits of these methods in comparison to classical physics-based design methods and identifying deficiencies for improvement.

7.
J Proteome Res ; 23(6): 2148-2159, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38785273

RESUMEN

Diverse proteomics-based strategies have been applied to saliva to quantitatively identify diagnostic and prognostic targets for oral cancer. Considering that these targets may be regulated by events that do not imply variation in protein abundance levels, we hypothesized that changes in protein conformation can be associated with diagnosis and prognosis, revealing biological processes and novel targets of clinical relevance. For this, we employed limited proteolysis-mass spectrometry in saliva samples to explore structural alterations, comparing the proteome of healthy control and oral squamous cell carcinoma (OSCC) patients with and without lymph node metastasis. Thirty-six proteins with potential structural rearrangements were associated with clinical patient features including transketolase and its interacting partners. Moreover, N-glycosylated peptides contribute to structural rearrangements of potential diagnostic and prognostic markers. Altogether, this approach utilizes saliva proteins to search for targets for diagnosing and prognosing oral cancer and can guide the discovery of potential regulated sites beyond protein-level abundance.


Asunto(s)
Neoplasias de la Boca , Proteoma , Saliva , Humanos , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Neoplasias de la Boca/diagnóstico , Saliva/química , Saliva/metabolismo , Proteoma/análisis , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/diagnóstico , Femenino , Biomarcadores de Tumor/metabolismo , Masculino , Metástasis Linfática , Conformación Proteica , Persona de Mediana Edad , Pronóstico , Proteómica/métodos , Transcetolasa/metabolismo , Anciano , Espectrometría de Masas , Proteínas y Péptidos Salivales/metabolismo , Proteínas y Péptidos Salivales/análisis
8.
Environ Monit Assess ; 196(6): 499, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38696108

RESUMEN

Due to the anthropogenic pressures of expansion areas for livestock and agricultural production in the Brazilian Cerrado, it is of paramount importance to understand the dynamics of land use/land cover (LULC) changes in this region. Thus, we investigated LULC changes in two sub-basins of the Tocantins-Araguaia River basin from 1997 to 2015 and consequently projected future changes for the timespan between 2030 and 2050. The Formoso sub-basin experienced significant expansion of agricultural and pasture areas, whereas the Sono sub-basin limited farmland expansion (more stable native vegetation) due to substantial protected areas, trends that were also observed for future projections (2030 and 2050). Pastureland in the Formoso sub-basin increased by 5.8%, while the Sono sub-basin saw significant gains in cultivated land, according to change detection analyses during the 1997-2015 period. High stability probabilities of no change (> 70%) for grassland areas in the Sono River sub-basin and pasturelands in the Formoso River sub-basin were computed. The CA-Markov model demonstrated a high consistency level with actual LULC classes for both sub-basins, as indicated by an overall Kappa coefficient above 0.8. Future projections for 2030 and 2050 show a substantial expansion of agriculture and pasture in both sub-basins, driven by specific factors such as soil organic carbon stocks, distance from rural settlements, and proximity to rivers. Short- and mid-term simulations indicate substantial expansion of agriculture and pasture in both basins, with potential adverse impacts on water erosion. Consequently, developing policies for soil management and sustainable land use planning is essential for agroecosystem sustainability, promoting a balanced approach to economic development while addressing climate change and anthropogenic challenges.


Asunto(s)
Agricultura , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Ríos , Ríos/química , Monitoreo del Ambiente/métodos , Brasil
9.
Sensors (Basel) ; 24(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38610305

RESUMEN

The flexibility and versatility associated with autonomous mobile robots (AMR) have facilitated their integration into different types of industries and tasks. However, as the main objective of their implementation on the factory floor is to optimize processes and, consequently, the time associated with them, it is necessary to take into account the environment and congestion to which they are subjected. Localization, on the shop floor and in real time, is an important requirement to optimize the AMRs' trajectory management, thus avoiding livelocks and deadlocks during their movements in partnership with manual forklift operators and logistic trains. Threeof the most commonly used localization techniques in indoor environments (time of flight, angle of arrival, and time difference of arrival), as well as two of the most commonly used indoor localization methods in the industry (ultra-wideband, and ultrasound), are presented and compared in this paper. Furthermore, it identifies and compares three industrial indoor localization solutions: Qorvo, Eliko Kio, and Marvelmind, implemented in an industrial mobile platform, which is the main contribution of this paper. These solutions can be applied to both AMRs and other mobile platforms, such as forklifts and logistic trains. In terms of results, the Marvelmind system, which uses an ultrasound method, was the best solution.

10.
Phys Chem Chem Phys ; 26(15): 11436-11444, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38567569

RESUMEN

Bottom-up mechanochemical synthesis (BUMS) has been demonstrated to be an efficient approach for the preparation of metal nanoparticles (NPs), protected by surface agents or anchored on solid supports. However, there are limitations, such as precise size and morphological control, due to a lack of knowledge about the mechanically induced processes of NP formation under milling. In this article, we further investigate the BUMS of AuNPs. Using SiO2 as a solid support, we studied the effect of typical reducing agents, namely NaBH4, L-ascorbic acid, and hydroquinone (HQ), on the conversion of a AuIII source. XANES showed that HQ is the strongest reducing agent under our experimental conditions, leading to the quantitative conversion of gold salt in a few minutes. Interestingly, even when HQ was used in sub-stoichiometric amounts, AuIII could be reduced to ratios higher than 85% after two minutes of milling. Investigations into the byproducts by 1H NMR and GC-FID/MS enabled the identification HQ regeneration and the formation of its derivatives. We mainly focused on benzoquinone (BQ), which is the product of the oxidation of HQ as it reduces the gold salt. We could demonstrate that HQ is regenerated from BQ exclusively under milling and acidic conditions. The regenerated HQ and other HQ-chlorinated molecules could then reduce gold-oxidized species, leading to higher conversions and economy of reactants. Our study highlights the intriguing and complex mechanisms of mechanochemical systems, in addition to fostering the atom and energy economy side of mechanochemical means to produce metal nanoparticles.

11.
Talanta ; 274: 126042, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583326

RESUMEN

This work emphasizes the utilization of biochar, a renewable material, as an interesting platform for anchoring redox mediators and bioreceptors in the development of economic, environmentally friendly biosensors. In this context, Fe(III) ions were preconcentrated on highly functionalized activated biochar, allowing the stable synthesis of Prussian blue nanostructures with an average size of 58.3 nm. The determination of glucose was carried out by indirectly monitoring the hydrogen peroxide generated through the enzymatic reaction, followed by its subsequent redox reaction with reduced Prussian blue (also known as Prussian white) in a typical electrochemical-chemical mechanism. The EDC/NHS (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-Hydroxysuccinimide) pair was employed for the stable covalent immobilization of the enzyme on biochar. The biosensor demonstrated good enzyme-substrate affinity, as evidenced by the Michaelis-Menten apparent kinetic constant (4.16 mmol L-1), and analytical performance with a wide linear dynamic response range (0.05-5.0 mmol L-1), low limits of detection (0.94 µmol L-1) and quantification (3.13 µmol L-1). Additionally, reliable repeatability, reproducibility, stability, and selectivity were obtained for the detection of glucose in both real and spiked human saliva and blood serum samples.


Asunto(s)
Técnicas Biosensibles , Carbón Orgánico , Ferrocianuros , Glucosa , Nanoestructuras , Ferrocianuros/química , Técnicas Biosensibles/métodos , Nanoestructuras/química , Carbón Orgánico/química , Glucosa/análisis , Glucosa/química , Humanos , Enzimas Inmovilizadas/química , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Glucemia/análisis , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Límite de Detección
12.
Commun Biol ; 7(1): 371, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575811

RESUMEN

Cardiac function requires appropriate proteins in each chamber. Atria requires slow myosin to act as reservoirs, while ventricles demand fast myosin for swift pumping. Myosins are thus under chamber-biased cis-regulation, with myosin gene expression imbalances leading to congenital heart dysfunction. To identify regulatory inputs leading to cardiac chamber-biased expression, we computationally and molecularly dissected the quail Slow Myosin Heavy Chain III (SMyHC III) promoter that drives preferential expression to the atria. We show that SMyHC III gene states are orchestrated by a complex Nuclear Receptor Element (cNRE) of 32 base pairs. Using transgenesis in zebrafish and mice, we demonstrate that preferential atrial expression is achieved by a combinatorial regulatory input composed of atrial activation motifs and ventricular repression motifs. Using comparative genomics, we show that the cNRE might have emerged from an endogenous viral element through infection of an ancestral host germline, revealing an evolutionary pathway to cardiac chamber-specific expression.


Asunto(s)
Atrios Cardíacos , Pez Cebra , Ratones , Animales , Pez Cebra/genética , Atrios Cardíacos/metabolismo , Ventrículos Cardíacos , Miosinas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo
13.
Environ Sci Technol ; 58(10): 4510-4521, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38426442

RESUMEN

Polystyrene (PS) is one of the main synthetic polymers produced around the world, and it is present in the composition of a wide variety of single-use objects. When released into the environment, these materials are degraded by environmental factors, resulting in microplastics. We investigated the ability of Chironomus sancticaroli (Diptera, Chironomidae) to promote the fragmentation of PS microspheres (24.5 ± 2.9 µm) and the toxic effects associated with exposure to this polymer. C. sancticaroli larvae were exposed to 3 different concentrations of PS (67.5, 135, and 270 particles g-1 of dry sediment) for 144 h. Significant lethality was observed only at the highest concentration. A significant reduction in PS particle size as well as evidence of deterioration on the surface of the spheres, such as grooves and cracks, was observed. In addition, changes in oxidative stress biomarkers (SOD, CAT, MDA, and GST) were also observed. This is the first study to report the ability of Chironomus sp. to promote the biofragmentation of microplastics. The information obtained demonstrates that the macroinvertebrate community can play a key role in the degradation of plastic particles present in the sediment of freshwater environments and can also be threatened by such particle pollution.


Asunto(s)
Chironomidae , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Larva , Poliestirenos/toxicidad , Chironomidae/metabolismo , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis
14.
Cell Death Dis ; 15(3): 200, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459002

RESUMEN

During aging, muscle regenerative capacities decline, which is concomitant with the loss of satellite cells that enter in a state of irreversible senescence. However, what mechanisms are involved in myogenic senescence and differentiation are largely unknown. Here, we showed that early-passage or "young" C2C12 myoblasts activated the redox-sensitive p66Shc signaling pathway, exhibited a strong antioxidant protection and a bioenergetic profile relying predominantly on OXPHOS, responses that decrease progressively during differentiation. Furthermore, autophagy was increased in myotubes. Otherwise, late-passage or "senescent" myoblasts led to a highly metabolic profile, relying on both OXPHOS and glycolysis, that may be influenced by the loss of SQSTM1/p62 which tightly regulates the metabolic shift from aerobic glycolysis to OXPHOS. Furthermore, during differentiation of late-passage C2C12 cells, both p66Shc signaling and autophagy were impaired and this coincides with reduced myogenic capacity. Our findings recognized that the lack of p66Shc compromises the proliferation and the onset of the differentiation of C2C12 myoblasts. Moreover, the Atg7 silencing favored myoblasts growth, whereas interfered in the viability of differentiated myotubes. Then, our work demonstrates that the p66Shc signaling pathway, which highly influences cellular metabolic status and oxidative environment, is critical for the myogenic commitment and differentiation of C2C12 cells. Our findings also support that autophagy is essential for the metabolic switch observed during the differentiation of C2C12 myoblasts, confirming how its regulation determines cell fate. The regulatory roles of p66Shc and autophagy mechanisms on myogenesis require future attention as possible tools that could predict and measure the aging-related state of frailty and disability.


Asunto(s)
Mioblastos , Transducción de Señal , Autofagia/genética , Diferenciación Celular/fisiología , Línea Celular , Desarrollo de Músculos/genética , Mioblastos/metabolismo , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/genética , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/metabolismo , Animales , Ratones
15.
PeerJ ; 12: e17026, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38426130

RESUMEN

Background: General expectations speculated that there are differences between drop jump (DJ) and horizontal drop jump (HDJ) exercises. While these criteria may be valid, we have yet to find a report that explores these differences in competitive level athletes. Objective: The study aimed to compare spatiotemporal variables in the drop jump (DJ) vs. the horizontal drop jump (HDJ) in elite jumpers and sprinters. Methods: Sixteen international-level male athletes performed two DJ attempts at different fall heights 0.3, 0.4, and 0.5 m (DJ30, DJ40, and DJ50), and after 2 h, they performed two HDJ attempts (HDJ30, HDJ40, HDJ50). All jumps were performed on a Kistler force plate. The variables analyzed were ground contact time (GCT), flight time (FT), eccentric phase time, concentric phase time, and time to peak concentric force. Results: The GCT was found to be significantly shorter in DJ vs. HDJ (Z = 4.980; p = 0.0001; ES = 3.11). FT was significantly lower in DJ30 versus HDJ30 (Z = 4.845; p = 0.0001, d = 3.79), but significantly higher in DJ40 vs. HDJ40 (Z = 4.437; p ≤ 0.0001, d = 3.70) and in DJ50 vs. HDJ50 (Z = 4.549; p ≤ 0.0001, d = 4.72). Conclusions: It is concluded that the HDJ requires more time for force production, that the eccentric component requires more time than the concentric and that it is not recommended to use the HDJ over the DJ for reactive purposes. This is the first study that comprehensively compare the differences between DJ and HDJ, which will assist coaches and researchers in the design of future training strategies.


Asunto(s)
Rendimiento Atlético , Humanos , Masculino , Fuerza Muscular , Atletas , Ejercicio Físico , Prueba de Esfuerzo
16.
Physiol Rev ; 104(3): 1387-1408, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38451234

RESUMEN

Effective data management is crucial for scientific integrity and reproducibility, a cornerstone of scientific progress. Well-organized and well-documented data enable validation and building on results. Data management encompasses activities including organization, documentation, storage, sharing, and preservation. Robust data management establishes credibility, fostering trust within the scientific community and benefiting researchers' careers. In experimental biomedicine, comprehensive data management is vital due to the typically intricate protocols, extensive metadata, and large datasets. Low-throughput experiments, in particular, require careful management to address variations and errors in protocols and raw data quality. Transparent and accountable research practices rely on accurate documentation of procedures, data collection, and analysis methods. Proper data management ensures long-term preservation and accessibility of valuable datasets. Well-managed data can be revisited, contributing to cumulative knowledge and potential new discoveries. Publicly funded research has an added responsibility for transparency, resource allocation, and avoiding redundancy. Meeting funding agency expectations increasingly requires rigorous methodologies, adherence to standards, comprehensive documentation, and widespread sharing of data, code, and other auxiliary resources. This review provides critical insights into raw and processed data, metadata, high-throughput versus low-throughput datasets, a common language for documentation, experimental and reporting guidelines, efficient data management systems, sharing practices, and relevant repositories. We systematically present available resources and optimal practices for wide use by experimental biomedical researchers.


Asunto(s)
Investigación Biomédica , Manejo de Datos , Difusión de la Información , Investigación Biomédica/normas , Investigación Biomédica/métodos , Difusión de la Información/métodos , Humanos , Animales , Manejo de Datos/métodos
17.
J Fish Biol ; 104(5): 1290-1298, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38299718

RESUMEN

This study delves into the foraging ecology of the cookiecutter shark (Isistius brasiliensis) in the Saint Peter and Saint Paul Archipelago (SPSPA), assessing bite marks on pelagic fishes collected between March and September 2018. Examination of 200 individuals from five species revealed the shark's predilection for targeting adult fish, ensuring efficient removal of energy-rich tissue layers. However, a notable exception is Thunnus albacares, preyed on predominantly during its juvenile stage, possibly due to vertical spatial segregation. Recent bites were pervasive across species, with wahoo displaying a distinctive pattern. Cookiecutter shark bites predominantly targeted the lateral body portion (>55%) except for yellowfin tuna, which exhibited a preference for the ventral region (95%). The estimated length distribution suggests the SPSPA as a potential nursery area for cookiecutter sharks. Bite mark positions and frequencies may be linked to fish behavior, swimming velocity, and fishing gear strategy, highlighting the complex interplay in pelagic ecosystems.


Asunto(s)
Conducta Alimentaria , Conducta Predatoria , Tiburones , Animales , Tiburones/fisiología , Océano Atlántico
18.
Sci Rep ; 14(1): 4559, 2024 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-38402243

RESUMEN

Simulating future land use changes can be an important tool to support decision-making, especially in areas that are experiencing rapid anthropogenic pressure, such as the Cerrado-Brazilian savanna. Here we used a spatially-explicit model to identify the main drivers of native vegetation loss in the Cerrado and then extrapolate this loss for 2050 and 2070. We also analyzed the role of property size in complex Brazilian environmental laws in determining different outcomes of these projections. Our results show that distance to rivers, roads, and cities, agricultural potential, permanent and annual crop agriculture, and cattle led to observed/historical loss of vegetation, while protected areas prevented such loss. Assuming full adoption of the current Forest Code, the Cerrado may lose 26.5 million ha (± 11.8 95% C.I.) of native vegetation by 2050 and 30.6 million ha (± 12.8 95% C.I.) by 2070, and this loss shall occur mainly within large properties. In terms of reconciling conservation and agricultural production, we recommend that public policies focus primarily on large farms, such as protecting 30% of the area of properties larger than 2500 ha, which would avoid a loss of more than 4.1 million hectares of native vegetation, corresponding to 13% of the predicted loss by 2070.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Animales , Bovinos , Brasil , Bosques , Agricultura , Ecosistema
19.
ACS Appl Mater Interfaces ; 16(9): 11467-11478, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38382920

RESUMEN

Plasmonic photocatalysis has been limited by the high cost and scalability of plasmonic materials, such as Ag and Au. By focusing on earth-abundant photocatalyst/plasmonic materials (HxMoO3) and Pd as a catalyst, we addressed these challenges by developing a solventless mechanochemical synthesis of Pd/HxMoO3 and optimizing photocatalytic activities in the visible range. We investigated the effect of HxMoO3 band gap excitation (at 427 nm), Pd interband transitions (at 427 nm), and HxMoO3 localized surface plasmon resonance (LSPR) excitation (at 640 nm) over photocatalytic activities toward the hydrogen evolution and phenylacetylene hydrogenation as model reactions. Although both excitation wavelengths led to comparable photoenhancements, a 110% increase was achieved under dual excitation conditions (427 + 640 nm). This was assigned to a synergistic effect of optical excitations that optimized the generation of energetic electrons at the catalytic sites. These results are important for the development of visible-light photocatalysts based on earth-abundant components.

20.
Sci Rep ; 14(1): 2080, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267489

RESUMEN

The presence of Andean plant genera in moist forests of the Brazilian Atlantic Coast has been historically hypothesized as the result of cross-continental migrations starting at the eastern Andean flanks. Here we test hypotheses of former connections between the Atlantic and Andean forests by examining distribution patterns of selected cool and moist-adapted plant arboreal taxa present in 54 South American pollen records of the Last Glacial Maximum (LGM), ca. 19-23 cal ka, known to occur in both plant domains. Pollen taxa studied include Araucaria, Drimys, Hedyosmum, Ilex, Myrsine, Podocarpus, Symplocos, Weinmannia, Myrtaceae, Ericaceae and Arecaceae. Past connectivity patterns between these two neotropical regions as well as individual ecological niches during the LGM were explored by cluster analysis of fossil assemblages and modern plant distributions. Additionally, we examined the ecological niche of 137 plant species with shared distributions between the Andes and coastal Brazil. Our results revealed five complex connectivity patterns for South American vegetation linking Andean, Amazonian and Atlantic Forests and one disjunction distribution in southern Chile. This study also provides a better understanding of vegetation cover on the large and shallow South American continental shelf that was exposed due to a global sea level drop.


Asunto(s)
Ecosistema , Bosques , Brasil , Chile , Árboles
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