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1.
Small ; : e2405817, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377313

RESUMEN

2D MXene nanomaterials have excellent potential for application in novel electrochemical energy storage technologies such as supercapacitors and batteries, but the existing pure MXene is difficult to meet the practical needs. Although the electrochemical properties of modified MXene have been improved, the unclear ion storage mechanism still hinders the development of MXene-based electrode materials. Herein, the study develops flexible self-supported nitrogen-doped Ti3C2 (Py-Ti3C2) films by the highly mobile, high nitrogen content, oxygen-free pyridine-assisted solvothermal method, and then deeply investigates the energy storage mechanism of hybrid supercapacitors in four aqueous electrolytes (H2SO4, Li2SO4, Na2SO4, and MgSO4). The experimental results suggest that the Py-Ti3C2 film electrode exhibits a pseudocapacitance-dominated energy storage mechanism. Particularly, the specific capacity of the Py-Ti3C2 in 1 M H2SO4 (506 F g-1 at 0.1 A g-1) is 4-5 times higher than other electrolytes (≈110 F g-1), which could be attributed to the substantially higher ionic diffusion coefficient of H+ than those of Li+, Na+, Mg2+ with small ionic size, high ionic conductivity, and fast pseudocapacitance response. Theoretical analysis further confirms that Py-Ti3C2 has strengthened conductivity and electrical double-layer capacitance performance. Meanwhile, it has lower free energy for protonation and deprotonation of functional groups, which gives excellent pseudocapacitance performance.

2.
Sci Rep ; 14(1): 22937, 2024 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-39358407

RESUMEN

Although sodium-glucose transport protein-2 (SGLT2) inhibitors (SGLT2i) do not increase the risk of acute kidney injury (AKI) in general, they may pose a risk in patients undergoing angiography. This prospective cohort study aimed to evaluate the safety and efficacy of SGLT2i for post-contrast AKI (PC-AKI) in patients with type 2 diabetes mellitus (T2DM). Following screening, 306 patients with T2DM selected to undergo coronary arterial angiography with or without percutaneous intervention were enrolled. Patients were divided into the SGLT2i exposure and non-exposure groups. The primary outcome was PC-AKI, defined as an increase in serum creatinine levels > 0.5 mg/dL (44.2 µmol/L), or 25% above the baseline, within 48-72 h after exposure to contrast medium. The incidence of PC-AKI in the overall T2DM population was 5.2% (16/306). Following 1:1 propensity score matching, the incidence of PC-AKI was significantly higher in the SGLT2i group than in the non-SGLT2i group (10.7% vs. 2.9%; P = 0.027), with an odds ratio of 4.5 (95% confidence interval: 1.0-20.2; P = 0.047). Furthermore, PC-AKI occurred at a higher rate among short-term users of SGLT2i than long-term users (20.5% vs. 3.4%, P = 0.018). Thus, our findings suggest an increased risk of PC-AKI associated with short-term SGLT2i therapy in patients with T2DM.


Asunto(s)
Lesión Renal Aguda , Medios de Contraste , Diabetes Mellitus Tipo 2 , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Lesión Renal Aguda/inducido químicamente , Masculino , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Medios de Contraste/efectos adversos , Anciano , Persona de Mediana Edad , Estudios Prospectivos , Angiografía Coronaria/efectos adversos , Creatinina/sangre , Incidencia , Factores de Riesgo
3.
J Hazard Mater ; 480: 136068, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39378596

RESUMEN

Microplastics (MPs) potentially alter physicochemical and transformation of heavy metals (HMs) in soils, which may depend on the specific characteristics of soil types. However, the dynamical and long-term mechanisms remain to be elucidated. A five-year incubation experiment was conducted to evaluate the influence of MPs on the chemical speciation of Pb, Ni, Cu, Cr, Cd, and As in the meadow, tidal, cinnamon, saline-alkali, and brown soils. From the first year to the fifth year, the clay value of the meadow, tidal, cinnamon, and saline-alkali soils was increased by 31.35 %, 9.63 %, 30.12 %, and 33.12 %, respectively; the pH values of the cinnamon and saline-alkali soils were increased by 15.02 % and 15.86 %, respectively. Besides, speciation distribution results suggested that the application of MPs reduced the liable available (LB) form (F2-dissolved and F3-ion exchangeable) of HMs and increased the potentially available (PB) form (F5-minerals and F6-organic-bound fraction) of HMs in all soils. Compared with other forms, F2 HMs fraction was the most responsive to MPs. Furthermore, the average bioconcentration factor (BCF) of Cr and Pb decreased by 73.75 % and 70.41 % in soils, respectively. Interestingly, soil type showed more impact on the form of HMs, which was associated with the different physicochemical parameters of soils, while application time displayed more impact on the bioavailability of HMs. Moreover, our results suggested that soils with higher clay content and pH values (such as cinnamon and saline-alkali soils) may mitigate the bioavailability of HMs more effectively in the presence of MPs, while soils with lower clay content may be more vulnerable to HMs contamination over time. This work highlights the importance of long-term monitoring of the impact of MPs on HMs dynamics for effective mitigation of soil contamination risks. Our study provides valuable guidance for soil remediation strategies and environmental quality management across different soil types.

4.
ACS Nano ; 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39380455

RESUMEN

Nanofertilizers comprising engineered nanoparticles (ENPs) have great potential in sustainable agriculture due to their strong capabilities of improving crop yields. As an effective fertilization strategy, foliar spraying could lead to broken and splashed ENP droplets, resulting in inaccurate leaf targeting and potential environmental contamination. Herein, we propose embedding Fe-based ENPs into a supramolecular hydrogel to effectively enhance the deposition amount on leaves and thus the bioavailability. The proper rheological properties of the hydrogel droplets and their robust interaction with soybean leaf simultaneously reduce the droplet rebound and fragmentation, especially under elevated impact speeds, resulting in up to 168.9% more droplet deposition compared to the ENP suspension. Computational fluid dynamics simulation analysis suggests that the contact angle is a key sensitive factor influencing the dynamic deposition behavior of the hydrogel droplet. A 15% reduction in the contact angle results in a 14% reduction of the highest bouncing height. The incorporation of ENPs enhances the viscous dissipation rate by 7.4% in comparison with pure hydrogel droplets. The hydrogel embedding also causes a 1.5-fold increase in ENP uptake compared to that of the ENP suspension. The hydrogel embedding delivers a reduction of 80% in the ENP application amount, compared to ENP suspensions, while achieving a 28% increase in the fresh weight of soybean seedlings. This work provides an effective method to enhance the deposition of ENPs during foliar application.

5.
J Orthop Surg Res ; 19(1): 657, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39402607

RESUMEN

BACKGROUND: Despite coalition resection being the preferred treatment for talocalcaneal coalition (TCC), postoperative complications, suboptimal functional recovery, and recurrence risks remain challenges. Although current TCC classification systems guide personalized surgical plans, the impact of middle and posterior facet coalitions on TCC resection surgery's effectiveness is still poorly understood. Therefore, this study aims to compare the clinical outcomes of TCC patients with and without involvement of the subtalar joint's (STJ) middle and posterior facets undergoing coalition resection to explore the potential impact of these coalitions on surgical outcomes. METHODS: We conducted a retrospective study on 115 patients who underwent coalition resection surgery due to symptomatic TCC between November 2009 and February 2023. According to preoperative CT scan results, patients were divided into an isolated posterior facet coalition (P-type) group and a middle-posterior facet coalition (MP-type) group. Demographic characteristics (including age, sex, body mass index (BMI), follow-up time, and medical history duration), pre-and postoperative assessments (including Visual Analog Scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) score, Pain Interference (PI) and Physical Function (PF) scores from the Patient-Reported Outcomes Measurement Information System (PROMIS)), as well as postoperative self-assessment of efficacy (excellent, good, fair, poor) and hindfoot stiffness, were compared between the two groups. Postoperatively, TCC recurrence was evaluated through imaging follow-up examinations. RESULTS: 69 patients meeting the inclusion criteria were included, with 30 patients in the P-type group and 39 in the MP-type group. There were no statistically significant differences between the two groups in demographic characteristics (P<0.05). There were also no statistically significant differences between the two groups in preoperative VAS score, AOFAS score, PI score, and PF score. However, postoperatively, there were statistically significant differences between the two groups in VAS score (1(1,1.5) vs. 2(1,2), P<0.01), AOFAS score (92.5(87,96.5) vs. 82(69.5,87), P<0.01), PI score (39(39,43) vs. 39(39,51), P = 0.014), PF score (73(61,73) vs. 55(51,73), P = 0.001), fair or poor outcome (4(13%) vs. 14(35.9%), P = 0.034), and hindfoot stiffness (3(10.3%) vs. 16(37.2%), P = 0.011). There was no statistically significant differences in the recurrence rate between the two groups postoperatively (0(0%) vs. 3(7.69%), P = 0.252). CONCLUSION: Even with complete coalition resection during surgery and rehabilitation following standardized protocols, the surgical outcomes in MP-type TCC patients are still inferior to those in P-type patients.


Asunto(s)
Articulación Talocalcánea , Humanos , Estudios Retrospectivos , Femenino , Masculino , Articulación Talocalcánea/cirugía , Articulación Talocalcánea/diagnóstico por imagen , Resultado del Tratamiento , Adulto , Adolescente , Adulto Joven , Estudios de Cohortes , Coalición Tarsiana/cirugía , Coalición Tarsiana/diagnóstico por imagen , Estudios de Seguimiento , Complicaciones Posoperatorias/etiología
6.
Bioresour Technol ; 414: 131567, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39393651

RESUMEN

Microbial biofilms provide advantages in fermentation processes. However, Corynebacterium glutamicum (C. glutamicum) usually exhibits relatively poor biofilm formation compared to other industrial strains. To develop a biofilm-enhanced fermentation process for C. glutamicum, seven genes potentially related to biofilm formation in C. glutamicum were systematically investigated, which include ppk2B, glgC, virB11, cslA, NCgl2909, NCgl0350 and exeR. Deletion of the NCgl0350, NCgl2909 genes and heterologous expression of the cslA gene were found to increase biofilm amounts by 16.9%, 21.2% and 135%, respectively, compared to the wild-type strain. Meanwhile, the production of L-lysine by engineered strains was assessed in biofilm-based continuous fermentation. The most notable result was observed for the cslA-expressing strain, which produced an average of 26.1% higher L-lysine compared with that of wild-type strain in 6-L bioreactors. In conclusion, this study offers valuable insights into the biofilm formation in C. glutamicum and its application in continuous fermentation processes.

7.
Artículo en Inglés | MEDLINE | ID: mdl-39413406

RESUMEN

The global shortage of freshwater resources is becoming more and more serious; therefore, it is necessary to obtain freshwater by desalinating seawater resources. Solar-driven interfacial photothermal evaporation, which is an environmentally friendly and energy-efficient technology, has been used to desalinate seawater for water purification and production. Herein, the IPCA hydrogel with abundant pores consisting of carbon ink as a photothermal conversion material and PU sponge loaded with calcium alginate as a water transport medium was successfully prepared and used to obtain portable water. The parameters of the synthesized IPCA are optimized by Response Surface Methodology analysis, and it was found that the IPCA exhibits a high evaporation efficiency of 3.779 kg m-2 h-1 and up to 95.98% of photothermal conversion capacity under one solar intensity. It maintains a high evaporation efficiency and salt resistance after 10 cycles of evaporation in actual seawater. Moreover, IPCA shows a high removal of various organic dye pollutants in wastewater. The results suggest a new approach for the preparation of simple, efficient, and green solar evaporators in practical application.

8.
Integr Zool ; 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39415358

RESUMEN

Many plants exhibit a canopy seed bank, where seeds persist within the canopy for prolonged periods, gradually descending over time and potentially influencing seed predation and animal-mediated dispersal. However, the impact of delayed seed drop on animal predation and seed dispersal remains unclear. We used Chinese Armand pine seeds to simulate delayed seed drop of the canopy seed bank by releasing 7800 pine seeds in both winter and the following summer over 2 years, tracking their fates to investigate its effect on seed predation and dispersal by rodents in a pine plantation in southwest China. Results showed significant seasonal differences in seed fate. In summer, seeds experienced higher predation rates (62.08% vs 3.80% in winter) and lower scatter-hoarding rates (4.18% vs 15.40% in winter). Additionally, seeds in summer were dispersed farther (4.20 m vs. 3.56 m in winter) and primarily formed single-seed caches, as opposed to multi-seed caches in winter. Although delayed seed drop increased immediate predation risks, favorable summer conditions allowed for rapid germination, reducing long-term exposure to predation. In conclusion, while delayed seed drop increases immediate predation risks and reduces caching, it concurrently enhances dispersal distances and reduces cache size.

9.
Nat Commun ; 15(1): 8534, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39358376

RESUMEN

Grain boundaries in noble metal catalysts have been identified as critical sites for enhancing catalytic activity in electrochemical reactions such as the oxygen reduction reaction. However, conventional methods to modify grain boundary density often alter particle size, shape, and morphology, obscuring the specific role of grain boundaries in catalytic performance. This study addresses these challenges by employing gold nanoparticle assemblies to control grain boundary density through the manipulation of nanoparticle collision frequency during synthesis. We demonstrate a direct correlation between increased grain boundary density and enhanced two-electron oxygen reduction reaction activity, achieving a significant improvement in both specific and mass activity. Additionally, the gold nanoparticle assemblies with high grain boundary density exhibit remarkable electrochemical stability, attributed to boron segregation at the grain boundaries, which prevents structural degradation. This work provides a promising strategy for optimizing the activity, selectivity, and stability of noble metal catalysts through precise grain boundary engineering.

10.
ACS Nano ; 18(41): 28038-28051, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39363419

RESUMEN

The low permeability and heterogeneous distribution of drugs (including nanomedicines) have limited their deep penetration into solid tumors. Herein we report the design of gold nanoparticles with virus-like spikes (AuNVs) to mimic viral shapes and facilitate tumor penetration. Mechanistic studies revealed that AuNVs mainly entered cells through macropinocytosis, then transported to the Golgi/endoplasmic reticulum system via Rab11-regulated pathway, and finally exocytosed through recycling endosomes, leading to high cellular uptake, effective transcytosis, and deep tumor penetration compared to gold nanospheres (AuNPs) and gold nanostars (AuNSs). The high tumor accumulation and deep tumor penetration of mitoxantrone (MTO) facilitated by AuNVs endowed effective chemophotothermal therapy when exposed to a near-infrared II laser, significantly reducing tumor sizes in a mouse model of colorectal cancer. This study reveals a potent mechanism of viral-like structures in tissue penetration and highlights their potential as effective drug delivery carriers.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Oro , Rayos Infrarrojos , Animales , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/terapia , Ratones , Oro/química , Humanos , Antineoplásicos/química , Antineoplásicos/farmacología , Nanopartículas del Metal/química , Mitoxantrona/química , Mitoxantrona/farmacología , Mitoxantrona/farmacocinética , Terapia Fototérmica , Ratones Endogámicos BALB C , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Portadores de Fármacos/química , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular/efectos de los fármacos
11.
Ying Yong Sheng Tai Xue Bao ; 35(8): 2091-2098, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39419794

RESUMEN

Soil stoichiometric ratios serve as valuable indicators for the composition and quality of soil organic matter. While available studies predominantly examine the soil stoichiometric ratios of carbon (C), nitrogen (N), and phosphorus (P), limited attention has been paid on the influence of forest restoration on soil stoichiometric ratios of potassium (K), calcium (Ca), and magnesium (Mg). We analyzed soil K, Ca, and Mg content, as well as elemental stoichiometric ratios, in secondary forests with varying restoration periods (5, 8, 21, 27 and 40 years) and a natural forest, in order to examine the impact of forest restoration on soil stoichiometry. The results showed that soil C and N contents decreased significantly with increasing soil layers. Soil stoichiometric ratios decreased significantly with increasing soil layers except for K:P, Mg:P, and P:Ca. With the increases of forest restoration years, soil C and N contents significantly increased in 0-10 cm soil layer, Ca content in 10-20 cm soil layer significantly increased, and total P content in 20-40 cm layer significantly decreased. However, soil K and Mg contents in each soil layer did not differ among five restoration ages. With the increases of restoration years, C:Ca, N:Ca and P:Ca in 0-10 cm soil layer significantly increased, and C:P, N:P, and K:P in 20-40 cm soil layer significantly increased, while P:Ca in 20-40 cm soil layer significantly decreased. In all soil layers, K:P and Mg:P were significantly and negatively correlated with soil total P content, and C:Ca and N:Ca were significantly and positively correlated with soil mineral N, available P, and available K content. With the increases of the restoration ages of secondary forests, soils are gradually P-limited and progressively restricted by Ca element in the later years, leading to the limitation of multiple nutrients.


Asunto(s)
Calcio , Carbono , Bosques , Magnesio , Nitrógeno , Fósforo , Potasio , Suelo , Árboles , Suelo/química , Nitrógeno/análisis , Fósforo/análisis , Potasio/análisis , Carbono/análisis , Calcio/análisis , Magnesio/análisis , Árboles/crecimiento & desarrollo , Conservación de los Recursos Naturales , Clima Tropical , China , Restauración y Remediación Ambiental/métodos , Ecosistema
12.
Adv Mater ; : e2410536, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39420689

RESUMEN

Most patients with cancer are first diagnosed at an advanced disease stage, when tumors are already large and/or metastases are present. This circumstance has a negative impact on the prognosis and therapeutic effect of anticancer drugs. In this study, it is demonstrated that photosensitizer chlorin e6 and the photochemotherapy drug mitoxantrone self-assemble into relatively stable nanoassemblies (CM NAs) through hydrogen-bonding effect, π-π stacking, and hydrophobic interactions. Administration of CM NAs in combination with 660 nm laser irradiation shows chemotherapeutic, photothermal, and photodynamic effects, causing tumor cell apoptosis and pyroptosis and enabling noninvasive tumor ablation without compromising the surrounding normal tissue. More importantly, treatment with CM NAs increases tumor immunogenicity, leading to a strong and long-term antitumor immune response that eradicates large tumors and provides long-term protection against tumor recurrence on various tumor models.

13.
Adv Healthc Mater ; : e2401126, 2024 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-39344216

RESUMEN

The immunosuppressive microenvironment severely limits the responsiveness of colorectal cancer (CRC) to immunotherapy. Herein, a pH and reactive oxygen species (ROS) dual-responsive autocatalytic release system (TPDM/PGA) is constructed to reverse the immunosuppressive microenvironment and potentiate CRC immunotherapy. Dihydroartemisinin (DHA) and mitoxantrone (MTO) are conjugated to ROS-responsive polyethylenimine (TP) via a ROS-cleavable linker, respectively, and then coated with polyglutamic acid (PGA) to endow pH and ROS dual-responsiveness. The dissociation of PGA within the acidic TME facilitates its deep penetration and cell internalization, while the intracellular released DHA and MTO in response to high levels of H2O2 further produced a large amount of ROS, forming positive feedback to accelerate drug release and exacerbate oxidative stress. TPDM/PGA collaboratively reversed the immunosuppressive microenvironment and induced a strong anti-tumor immune response when combined with anti-PD-L1 antibody, significantly inhibiting tumor growth and prolonging the survival time of CT26 and MC38 tumor-bearing mice. The excellent therapeutic effect, together with the good tolerance, make TPDM/PGA a promising candidate for enhanced immunotherapy of colorectal cancer.

14.
Biomolecules ; 14(9)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39334873

RESUMEN

Arabinoside and derived nucleoside analogs, a family of nucleoside analogs, exhibit diverse typically biological activities and are widely used as antibacterial, antiviral, anti-inflammatory, antitumor, and other drugs in clinical and preclinical trials. Although with a long and rich history in the field of medicinal chemistry, the biosynthesis of arabinoside has only been sporadically designed and studied, and it remains a challenge. Here, we constructed an in vitro multi-enzymatic cascade for the biosynthesis of arabinosides. This artificial biosystem was systematically optimized, involving an exquisite pathway design, NADP+ regeneration, meticulous enzyme selection, optimization of the key enzyme dosage, and the concentration of inorganic phosphate. Under the optimized conditions, we achieved 0.37 mM of vidarabine from 5 mM of sucrose and 2 mM of adenine, representing 18.7% of the theoretical yield. Furthermore, this biosystem also has the capability to produce other arabinosides, such as spongouridine, arabinofuranosylguanine, hypoxanthine arabinofuranoside, fludarabine, and 2-methoxyadenine arabinofuranoside, from sucrose, and corresponding nucleobase by introducing different nucleoside phosphorylases. Overall, our biosynthesis approach provides a pathway for the biosynthesis of arabinose-derived nucleoside analogs, offering potential applications in the pharmaceutical industry.


Asunto(s)
Sacarosa , Sacarosa/metabolismo , Sacarosa/química , Vidarabina/análogos & derivados , Vidarabina/química , Vidarabina/metabolismo , Pentosiltransferasa/metabolismo , Pentosiltransferasa/genética , NADP/metabolismo
15.
ACS Nano ; 18(39): 26631-26642, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39297401

RESUMEN

Understanding the trophic transfer and ecological cascade effects of nanofertilizers and nanopesticides in terrestrial food chains is crucial for assessing their nanotoxicity and environmental risks. Herein, the trophic transfer of La2O3 (nLa2O3) and CuO (nCuO) nanoparticles from tomato leaves to Helicoverpa armigera (Lepidoptera: Noctuidae) caterpillars and their subsequent effects on caterpillar growth and intestinal health were investigated. We found that 50 mg/L foliar nLa2O3 and nCuO were transferred from tomato leaves to H. armigera, with particulate trophic transfer factors of 1.47 and 0.99, respectively. While nCuO exposure reduced larval weight gain more (34.7%) than nLa2O3 (11.3%), owing to higher oxidative stress (e.g., MDA and H2O2) and more serious intestinal pathological damage (i.e., crumpled columnar cell and disintegrated goblet cell) by nCuO. Moreover, nCuO exposure led to a more compact antagonism between the phyllosphere and gut microbiomes compared to nLa2O3. Specifically, nCuO exposure resulted in a greater increase in pathogenic bacteria (e.g., Mycobacterium, Bacillus, and Ralstonia) and a more significant decrease in probiotics (e.g., Streptomyces and Arthrobacter) than nLa2O3, ultimately destroying larval intestinal immunity. Altogether, our findings systematically revealed the cascade effect of metal oxide nanomaterials on higher trophic consumers through alteration in the phyllosphere and insect gut microbiome interaction, thus providing insights into nanotoxicity and environmental risk assessment of nanomaterials applied in agroecosystems.


Asunto(s)
Cadena Alimentaria , Microbioma Gastrointestinal , Nanopartículas del Metal , Estrés Oxidativo , Solanum lycopersicum , Animales , Solanum lycopersicum/microbiología , Solanum lycopersicum/efectos de los fármacos , Solanum lycopersicum/metabolismo , Estrés Oxidativo/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Nanopartículas del Metal/química , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/microbiología , Óxidos/química , Óxidos/farmacología , Hojas de la Planta/metabolismo , Cobre/farmacología , Cobre/química , Helicoverpa armigera
16.
Environ Sci Technol ; 58(39): 17355-17363, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39301696

RESUMEN

Solubility largely determines the impacts of aerosol Fe on marine ecosystems and human health. Currently, modeling studies have large uncertainties in aerosol Fe solubility due to inadequate understanding of the sources of dissolved Fe. This work investigated seasonal variations of Fe solubility in coarse and fine aerosols in Qingdao, a coastal city in the Northwest Pacific, and utilized a receptor model for source apportionment of total and dissolved aerosol Fe. Desert dust was found to be the main source of total Fe, contributing 65 and 81% annually to total Fe in coarse and fine particles, respectively; in contrast, dissolved aerosol Fe originated primarily from combustion, industrial, and secondary sources. The annual average contributions to dissolved Fe in coarse and fine particles were 68 and 47% for the secondary source and 32 and 33% for the combustion source, respectively. Aerosol Fe solubility was found to be highest in summer and lowest in spring, showing seasonal patterns similar to those of aerosol acidity. Increase in Fe solubility in atmospheric particles, when compared to desert dust, was mainly caused by secondary processing and combustion emission, and the effect of secondary processes was dictated by aerosol acidity and liquid water content.


Asunto(s)
Aerosoles , Polvo , Hierro , Solubilidad , Hierro/química , Estaciones del Año , Contaminantes Atmosféricos/análisis , Tamaño de la Partícula , Material Particulado , Monitoreo del Ambiente
17.
Environ Sci Technol ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39262330

RESUMEN

Sulfidation of nanoscale zerovalent iron (nZVI) can enhance particle performance. However, the underlying mechanisms of nZVI sulfidation are poorly known. We studied the effects of Fe2+ on 24-h dynamics of nZVI sulfidation by HS- using a dosed S to Fe molar ratio of 0.2. This shows that in the absence of Fe2+, HS- rapidly adsorbed onto nZVI particles and reacted with surface iron oxide to form mackinawite and greigite (<0.5 h). As nZVI corrosion progressed, amorphous FeSx in solution deposited on nZVI, forming S-nZVI (0.5-24 h). However, in the initial presence of Fe2+, the rapid reaction between HS- and Fe2+ produced amorphous FeSx, which deposited on the nZVI and corroded the surface iron oxide layer (<0.25 h). This was followed by redeposition of colloidal iron (hydr)oxide on the particle surface (0.25-8 h) and deposition of residual FeSx (8-24 h) on S-nZVI. S loading on S-nZVI was 1 order of magnitude higher when Fe2+ was present. Surface characterization of the sulfidated particles by TEM-SAED, XPS, and XAFS verified the solution dynamics and demonstrated that S2- and S22-/Sn2- were the principal reduced S species on S-nZVI. This study provides a methodology to tune sulfur loading and S speciation on S-nZVI to suit remediation needs.

18.
Small ; : e2406229, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263781

RESUMEN

Highly vertically thermally conductive silicon rubber (SiR) composites are widely used as thermal interface materials (TIMs) for chip cooling. Herein, inspired by water transport and transpiration of Moso bamboo-forests extensively existing in south China, and guided by filler self-assembly simulation, bamboo-forest-like heat conduction networks, with bamboo-stems-like vertically aligned polydopamine-coated carbon fibers (VA-PCFs), and bamboo-leaves-like horizontally layered Al2O3(HL-Al2O3), are rationally designed and constructed. VA-PCF/HL-Al2O3/SiR composites demonstrated enhanced heat conduction properties, and their through-plane thermal conductivity and thermal diffusivity reached 6.47 W (mK)-1 and 3.98 mm2 s-1 at 12 vol% PCF and 4 vol% Al2O3 loadings, which are 32% and 38% higher than those of VA-PCF (12 vol%) /SiR composites, respectively. The heat conduction enhancement mechanisms of VA-PCF/HL-Al2O3 networks on their SiR composites are revealed by multiscale simulation: HL-Al2O3 bridges the separate VA-PCF heat flow channels, and transfers more heat to the matrix, thereby increasing the vertical heat flux in composites. Along with high volume resistivity, low compression modulus, and coefficient of thermal expansion, VA-PCF/HL-Al2O3/SiR composites demonstrate great application potential as TIMs, which is proven using multiphysics simulation. This work not only makes a meaningful attempt at simulation-driven biomimetic material structure design but also provides inspiration for the preparation of TIMs.

19.
Org Lett ; 26(36): 7757-7762, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39267494

RESUMEN

A Cs2CO3-promoted [4 + 2] cycloaddition of 1,6-enynes under mild reaction conditions has been developed. This protocol provides a facile approach to a series of tetrahydro-1H-benzo[f]isoindole isomerized products promoted by Cs2CO3 with moderate to high yields. By simply switching the reaction solvent and controlling the reaction time, two isomerization products could be obtained, both with good selectivity.

20.
Molecules ; 29(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39274920

RESUMEN

OBJECTIVE: The aim of this study was to optimize the formulation of a C60-modified self-microemulsifying drug delivery system loaded with triptolide (C60-SMEDDS/TP) and evaluate the cytoprotective effect of the C60-SMEDDS/TP on normal human cells. RESULTS: The C60-SMEDDS/TP exhibited rapid emulsification, an optimal particle size distribution of 50 ± 0.19 nm (PDI 0.211 ± 0.049), and a near-neutral zeta potential of -1.60 mV. The release kinetics of TP from the C60-SMEDDS/TP exhibited a sustained release profile and followed pseudo-first-order release kinetics. Cellular proliferation and apoptosis analysis indicated that the C60-SMEDDS/TP (with a mass ratio of TP: DSPE-PEG-C60 = 1:10) exhibited lower toxicity towards L02 and GES-1 cells. This was demonstrated by a higher IC50 (40.88 nM on L02 cells and 17.22 nM on GES-1 cells) compared to free TP (21.3 nM and 11.1 nM), and a lower apoptosis rate (20.8% on L02 cells and 26.3% on GES-1 cells, respectively) compared to free TP (50.5% and 47.0%) at a concentration of 50 nM. In comparison to the free TP group, L02 cells and GES-1 cells exposed to the C60-SMEDDS/TP exhibited a significant decrease in intracellular ROS and an increase in mitochondrial membrane potential (ΔψM). On the other hand, the C60-SMEDDS/TP demonstrated a similar inhibitory effect on BEL-7402 cells (IC50 = 28.9 nM) and HepG2 cells (IC50 = 107.6 nM), comparable to that of the free TP (27.2 nM and 90.4 nM). The C60-SMEDDS/TP group also exhibited a similar intracellular level of ROS and mitochondrial membrane potential compared to the SMEDDS/TP and free TP groups. METHOD: Fullerenol-Grafted Distearoyl Phosphatidylethanolamine-Polyethylene Glycol (DSPE-PEG-C60) was synthesized and applied in the self-microemulsifying drug delivery system. The C60-SMEDDS/TP was formulated using Cremophor EL, medium-chain triglycerides (MCT), PEG-400, and DSPE-PEG-C60, and loaded with triptolide (TP). The toxicity and bioactivity of the C60-SMEDDS/TP were assessed using normal human liver cell lines (L02 cells), normal human gastric mucosal epithelial cell lines (GES-1 cells), and liver cancer cell lines (BEL-7402 cells and HepG2 cells). The production of reactive oxygen species (ROS) after the C60-SMEDDS/TP treatment was assessed using 2',7'-dichlorofluorescein diacetate (DCFDA) staining. The alterations in mitochondrial membrane potential (ΔψM) were assessed by measuring JC-1 fluorescence. CONCLUSIONS: The cytoprotection provided by the C60-SMEDDS/TP favored normal cells (L02 and GES-1) over tumor cells (BEL-7402 and HepG2 cells) in vitro. This suggests a promising approach for the safe and effective treatment of TP.


Asunto(s)
Apoptosis , Diterpenos , Sistemas de Liberación de Medicamentos , Emulsiones , Compuestos Epoxi , Fulerenos , Fenantrenos , Humanos , Diterpenos/farmacología , Diterpenos/química , Fenantrenos/química , Fenantrenos/farmacología , Compuestos Epoxi/química , Compuestos Epoxi/farmacología , Fulerenos/química , Fulerenos/farmacología , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Citoprotección/efectos de los fármacos , Tamaño de la Partícula , Proliferación Celular/efectos de los fármacos
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