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1.
Sci Rep ; 14(1): 22214, 2024 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333259

RESUMEN

This project utilized both field experiment and laboratory analyses to address the gap in understanding regarding the alterations in properties and functions of biochar, and the impact of heavy metal passivation in soil over long-term natural field aging. The study aimed to examine the changes in the physical and chemical characteristics of biochar over an extended period of natural aging. Additionally, it sought to analyze the impact and mechanisms of biochar in reducing of the harmful effects of the heavy metal cadmium (Cd) during the aging process. Both original and aged biochar conformed to the pseudo-second-order kinetics model and the Langmuir model. The aging process enhanced the adsorption of Cd by biochar and mitigated the leaching of Cd2+ into the soil. These findings provide a scientific basis for evaluating biochar's environmental behavior and its potential use in the remediation of soil contaminated with heavy metals.


Asunto(s)
Cadmio , Carbón Orgánico , Contaminantes del Suelo , Cadmio/química , Carbón Orgánico/química , Contaminantes del Suelo/química , Adsorción , Suelo/química , Cinética , Restauración y Remediación Ambiental/métodos
2.
EClinicalMedicine ; 76: 102816, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39290638

RESUMEN

Background: It is generally recognized that there is unequal mortality in childhood central nervous system (CNS) malignancy in the United States (US), but little is known about the trends and contributors of racial/ethnic disparities in death. We assessed the trends of racial/ethnic disparities in all-cause and cause-specific death, and the contributions of tumour, treatment and socioeconomic factors to this disparity. Methods: This registry-based cohort study included children (aged ≤19 years) diagnosed with malignant CNS tumours, using data from the US population-based cancer registry in the Surveillance, Epidemiology, and End Results (SEER) Program. The clinical outcomes were all-cause and cause-specific death for each racial/ethnic group (White, Black, Hispanic, non-Hispanic Asian/Pacific Islander [API], and non-Hispanic American Indian/Alaska Native [AI/AN] children). We quantified absolute disparities using absolute rate difference in 5-year cumulative incidence of death. Cox proportion risk models were used to estimate the relative racial/ethnic disparities, and the contribution of factors to disparities in death. Findings: In this study, data from 14,510 children with malignant CNS tumours (mean [SD] age, 8.5 [5.7]; 7988 [55.1%] male) were analysed. Overall, the cumulative incidence of death from CNS tumours across four racial/ethnic groups decreased from 2001 to 2020. Black patients had the highest risk of death from all causes and CNS tumours between 2001 and 2020, with adjusted hazard ratios (HR) of 1.52 (1.38-1.68) and 1.47 (1.31-1.64), respectively. The absolute disparity in all-cause death between Hispanic and White patients increased slightly (from 8.2 percentage points [ppt] to 9.4 ppt), and the relative disparity in death from CNS tumours increased from 1.33 (1.15-1.55) in 2001-2005 to 1.78 (1.44-2.20) in 2016-2020. The absolute disparities in death from CNS tumours between Black and White patients (from 11.8 ppt to 4.3 ppt) and between API and White patients (from 10.1 ppt to 5.1 ppt) decreased from 2001-2005 to 2011-2015. Interpretation: Race/ethnicity disparities in death from CNS tumours among childhood malignant CNS tumours had reduced from 2001 to 2020, and quantifying the contribution of factors to this disparity in death could provide a basis for decreasing mortality among racial/ethnic minority patients. Funding: Shenyang Young and Middle-aged Science and Technology Innovation Talent Support Program.

3.
Front Biosci (Landmark Ed) ; 29(9): 340, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39344329

RESUMEN

BACKGROUND: Alzheimer's disease (AD) poses a significant public health challenge, increasingly affecting patients' finances, mental health, and functional abilities as the global population ages. Stem cell-derived extracellular vesicles (SC-EVs) have emerged as a promising cell-free therapeutic approach for AD, although their precise mechanisms remain unclear. This meta-analysis aims to evaluate the effectiveness of SC-EVs in treating AD. METHODS: We systematically searched PubMed, EMBASE, and Web of Science databases up to December 31, 2023, identifying studies investigating SC-EVs therapy in AD rodent models. Outcome measures included Morris water maze and Y maze tests, ß-amyloid pathology, and inflammatory markers. Statistical analyses utilized Stata 15.1 and R software. RESULTS: This meta-analysis of 16 studies (2017-2023, 314 animals) demonstrates significant efficacy of SC-EVs therapy in AD models. Pooled analyses demonstrated that SC-EVs therapy significantly increased the learning function as measured by Morris water maze tests (MWM) by -1.83 (95% CI = -2.51 to -1.15, p < 0.0001), Y maze test by 1.66 (95% CI = 1.03 to 2.28, p < 0.0001), decreased Aß plaques in the hippocampal by -2.10 (95% CI = -2.96 to -1.23, p < 0.0001), and proinflammatory cytokines Tumor necrosis factor alpha (TNFα) by -2.61 (95% CI = -4.87 to -0.35, p < 0.05), Interleukin-1 beta (IL-1ß) by -2.37 (95% CI = -3.68 to -1.05, p < 0.001). CONCLUSIONS: SC-EVs therapy shows promise in enhancing cognitive function and mitigating AD progression in preclinical models. Future research should focus on standardizing methodologies and comparing SC-EVs isolation techniques and dosing strategies to facilitate clinical translation.


Asunto(s)
Enfermedad de Alzheimer , Vesículas Extracelulares , Enfermedad de Alzheimer/terapia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/trasplante , Animales , Humanos , Modelos Animales de Enfermedad , Células Madre/citología , Aprendizaje por Laberinto , Péptidos beta-Amiloides/metabolismo
4.
J Environ Manage ; 369: 122295, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39216353

RESUMEN

Global climate warming and human activities have increased the magnitude and frequency of Microcystis surface blooms, posing significant threats to freshwater ecosystems and human health over recent decades. Heavy rainfall events have been reported to cause the disappearance of these blooms. Although some studies have employed turbulence models to analyze the movement characteristics of Microcystis colonies, the impact of rainfall is complex, comprehensive investigations on their vertical migration induced by short-term rainfall are still necessary. Utilizing monitoring data from eutrophic ponds and controlled simulation experiments, this study examines the short-term impacts of rainfall on the vertical distribution of Microcystis in the water column. Our findings indicate that rainfall contributes to the disappearance of Microcystis blooms by reducing the quantity of small to medium-sized colonies (0-100 µm) at the surface, subsequently decreasing the overall Microcystis biomass. As rainfall intensity increases, larger colonies migrate deeper into the water column. At a rainfall threshold of 666 mm, the difference in the median volume diameter (DV50) of Microcystis colonies between the surface and bottom reaches a minimal value of 3.09%. Post-rainfall, these colonies rapidly ascend, aggregate into larger formations, and re-establish surface blooms. The greater the rainfall, the smaller the resultant Microcystis biomass, albeit with larger aggregated colony sizes. When rainfall exceeds 222 mm, the recovery rate of surface Microcystis biomass remains below 100%, decreasing to 19.48% at 666 mm of rainfall, while the median volume diameter (DV50) of the colonies increases to 139.07% of its pre-rainfall level. Furthermore, compared to pre-rainfall conditions, the photosynthetic activity of the surface Microcystis colonies was enhanced and the secretion of EPS was increased under heavy rainfall conditions. Our results identify a critical response time of 30 min for Microcystis colonies to rainfall, after which the response ceases to intensify. These insights are crucial for predicting post-rain Microcystis bloom dynamics and aiding management authorities in timely interventions.


Asunto(s)
Biomasa , Eutrofización , Microcystis , Lluvia , Microcystis/crecimiento & desarrollo , Ecosistema , Estanques
5.
Artículo en Inglés | MEDLINE | ID: mdl-39183230

RESUMEN

BACKGROUND: Pulsed field ablation (PFA) is an emerging non-thermal ablation method. The primary challenge is the control of multiple parameters in PFA, as the interplay of these parameters remains unclear in terms of ensuring effective and safe tissue ablation. PURPOSE: This study employs the response surface method (RSM) to explore the interactions between various PFA parameters and ablation outcomes, and seeks to enhance the efficacy and safety of PFA. METHODS: In vivo experiments were conducted using rabbit liver for varying PFA parameters: pulse amplitude (PA), pulse interval (PI), number of pulse trains (NT), and number of pulses in a pulse train (NP). Ablation outcomes assessed included three ablation sizes, surface temperature, and muscle contraction strength. Additionally, histological analysis was performed on the ablated tissue. We analyzed the relationship between PFA parameters and ablation outcomes, and results were then compared with those from a simulation using an electric-thermal coupling PFA finite element model. RESULTS: A linear relationship between ablation outcomes and PFA parameters was established. PA and NT exhibited extremely significant (P < 0.0001) and significant effects (P < 0.05) on all ablation outcomes, respectively. NP showed an extremely significant impact (P < 0.0001) on surface temperature and muscle contraction strength, while PI significantly influenced (P < 0.05) muscle contraction strength alone. Histological analysis revealed that PFA produces controlled, well-defined areas of liver tissue necrosis. Surface temperature results from simulations and experiments were highly consistent (R2 > 0.97). CONCLUSIONS: This study clarifies the relationship between various PFA parameters and ablation outcomes, and aims to improve the efficacy and safety of PFA.

6.
Chem Commun (Camb) ; 60(70): 9328-9339, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39113543

RESUMEN

Triphenylphosphine (TPP) salt derivatives, with their rich chemistry of core-substitution, have emerged as promising candidates for ultralong room temperature phosphorescence (RTP) materials owing to their distinct molecular structures, high quantum efficiency and exceptional phosphorescence properties. This feature article highlights the vast potential of TPP salt derivatives in tunable RTP properties by exploring some factors such as the alkyl chains, halogen anions, through-space charge transfer states, etc., and recent advancements in multi-level information encryption, high-level anticounterfeiting tags and X-ray imaging applications. We anticipate that this article will assist in directing future analyses based on the mechanisms underlying the RTP behavior of TPP derivatives and offer guidance for the rational design of high-performance RTP materials.

7.
J Am Chem Soc ; 146(32): 22413-22423, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39096292

RESUMEN

Stereochemically pure saccharides have indispensable roles in fields ranging from medicinal chemistry to materials science and organic synthesis. However, the development of a simple, stereoselective, and efficient glycosylation protocol to access α- and ß-C-glycosides (particularly 2-deoxy entities) remains a persistent challenge. Existing studies have primarily focused on C1 modification of carbohydrates and transformation of glycosyl radical precursors. Here, we innovate by harnessing the in situ generated glycosyl-Ni species to achieve one-pot borylation and glycosylation in a cascade manner, which is enabled by an earth-abundant nickel-catalyzed carboboration of readily accessible glycals without any ligand. This work reveals the potential for the development of a modular and multifunctional glycosylation platform to facilitate the simultaneous introduction of C-C and C-B bonds at the stereogenic center of saccharides, a largely unexploited research area. Preliminary experimental and computational studies indicate that the endocyclic O and the C3 group play important roles in stereoseclectively forging glycosidic bonds. As a result, a diverse range of C-R (R = alkyl, aryl, and alkenyl) and 2-deoxygenated glycosides bearing modifiable boron groups could be rapidly made with excellent stereocontrol and exhibit remarkable functional group tolerance. The synthetic potential is underscored in the late-stage glycosylation of natural products and commercial drugs as well as the facile preparation of various rare sugars, bioactive conjugates, and key intermediates to prorocentin, phomonol, and aspergillide A.

8.
Ecotoxicol Environ Saf ; 283: 116785, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39067075

RESUMEN

Tea tree is a fluorine (F)-enriched plant, leading to much concern about the safety of drinking tea from tea tree (Camellia sinensis (L.) Kuntze). Tea tree is a perennial leaf-harvested crop, and tea production in China is generally categorized as spring tea, summer tea and autumn tea in its annual growth rounds. However, the seasonally dynamic changes of F content and accumulation in the leaves and its drinking safety are poorly understood. In this study, 85 tea varieties cultivated under the same conditions were investigated to analyze the seasonal variation of F content and it's relationships with F accumulation, aluminum (Al), calcium (Ca) and manganese (Mn) and hazard quotient (HQ) in young leaves (one bud and two leaves, YL) and mature leaves (canopy leaves, ML). The average F contents and accumulations were 350 mg kg-1 and 203 g ha-1 in YL, and they were 2451 mg kg-1 and 2578 g ha-1 in ML, respectively, with F mainly accumulated in ML. As the growing season progresses, the F content showed a gradual increase in YL, while a decrease in ML, inferring that F may be redistributed from mature leaves to young leaves. Additionally, the F content was quite different among tea varieties which are suitable for processing oolong tea, green tea, and black tea, with higher F accumulation in oolong tea varieties than in green and black tea varieties. Moreover, F content and accumulation could be obviously affected by the geographical origin of the tea tree varieties, with significantly higher F content in the varieties from F rich fluorite belts than other regions. Furthermore, F content and accumulation showed a significant positive correlation with the content of Al and Mn (p < 0.05). Based on a daily tea consumption of 8.7 g, the HQ was investigated to show that the proportion of tea leaves with HQ<1 made from spring, summer and autumn tender leaves of 85 varieties was 100 %, 90.6 % and 50.6 %, respectively, indicating that the tea with the best drinking safety comes from spring, followed by summer, and then autumn. This result suggests that it could be necessary to avoid planting tea trees in fluorite mining areas, choose low F tea tree varieties, and control the tenderness of fresh leaves in order to ensure the safety of tea drinking.


Asunto(s)
Camellia sinensis , Flúor , Hojas de la Planta , Estaciones del Año , , Camellia sinensis/química , Hojas de la Planta/química , China , Medición de Riesgo , Flúor/análisis , Té/química , Manganeso/análisis , Aluminio/análisis , Calcio/análisis
9.
Front Endocrinol (Lausanne) ; 15: 1354214, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948525

RESUMEN

Background: Polycystic ovary syndrome (PCOS) is both a common endocrine syndrome and a metabolic disorder that results in harm to the reproductive system and whole-body metabolism. This study aimed to investigate differences in the serum metabolic profiles of patients with PCOS compared with healthy controls, in addition to investigating the effects of compound oral contraceptive (COC) treatment in patients with PCOS. Materials and methods: 50 patients with PCOS and 50 sex-matched healthy controls were recruited. Patients with PCOS received three cycles of self-administered COC treatment. Clinical characteristics were recorded, and the laboratory biochemical data were detected. We utilized ultra-performance liquid chromatography-high-resolution mass spectrometry to study the serum metabolic changes between patients with PCOS, patients with PCOS following COC treatment, and healthy controls. Result: Patients with PCOS who received COC treatment showed significant improvements in serum sex hormone levels, a reduction in luteinising hormone levels, and a significant reduction in the levels of biologically active free testosterone in the blood. Differential metabolite correlation analysis revealed differences between PCOS and healthy control groups in N-tetradecanamide, hexadecanamide, 10E,12Z-octadecadienoic acid, and 13-HOTrE(r); after 3 months of COC treatment, there were significant differences in benzoic acid, organic acid, and phenolamides. Using gas chromatography-mass spectrometry to analyse blood serum in each group, the characteristic changes in PCOS were metabolic disorders of amino acids, carbohydrates, and purines, with significant changes in the levels of total cholesterol, uric acid, phenylalanine, aspartic acid, and glutamate. Conclusion: Following COC treatment, improvements in sex hormone levels, endocrine factor levels, and metabolic levels were better than in the group of PCOS patients receiving no COC treatment, indicating that COC treatment for PCOS could effectively regulate the levels of sex hormones, endocrine factors, and serum metabolic profiles.


Asunto(s)
Metabolómica , Síndrome del Ovario Poliquístico , Humanos , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/metabolismo , Femenino , Metabolómica/métodos , Adulto , Adulto Joven , Estudios de Casos y Controles , Metaboloma/efectos de los fármacos , Testosterona/sangre , Anticonceptivos Orales/uso terapéutico , Anticonceptivos Orales Combinados/uso terapéutico , Biomarcadores/sangre
10.
Biosens Bioelectron ; 263: 116593, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39059178

RESUMEN

Nanozymes have garnered considerable research interest for their unique capacity to bridge nanotechnology and biology. Current studies predominantly concentrate on exploring nanozymes with diverse catalytic activities and their potential applications across various disciplines. Among them, nanoscale metal-organic frameworks (MOFs) are promising nanomaterials for constructing nanozymes. In this review, we firstly introduce the general construction strategies for MOF-based nanozymes. In addition, we also classify the MOF-based nanozymes in detail based on their catalytic performance. Thirdly, the recent research progress of MOF-based nanozymes in the field of biosensing, cancer therapy, antibacterial infection, and antioxidation are also comprehensively reviewed. Finally, we discuss the current challenges and future perspectives of MOF-based nanozymes, with the aim of assisting in their construction and maximizing their potential in bioapplications. It is hoped that we could provide scientists in materials science and biomedical research with valuable and comprehensive information, fostering advancements in interdisciplinary fields.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Nanoestructuras , Estructuras Metalorgánicas/química , Técnicas Biosensibles/métodos , Humanos , Nanoestructuras/química , Catálisis , Nanotecnología/métodos , Animales , Neoplasias/tratamiento farmacológico
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