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1.
J Cell Mol Med ; 28(16): e70022, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39205384

RESUMEN

Under the long-term pressure overload stimulation, the heart experiences embryonic gene activation, leading to myocardial hypertrophy and ventricular remodelling, which can ultimately result in the development of heart failure. Identifying effective therapeutic targets is crucial for the prevention and treatment of myocardial hypertrophy. Histone lysine lactylation (HKla) is a novel post-translational modification that connects cellular metabolism with epigenetic regulation. However, the specific role of HKla in pathological cardiac hypertrophy remains unclear. Our study aims to investigate whether HKla modification plays a pathogenic role in the development of cardiac hypertrophy. The results demonstrate significant expression of HKla in cardiomyocytes derived from an animal model of cardiac hypertrophy induced by transverse aortic constriction surgery, and in neonatal mouse cardiomyocytes stimulated by Ang II. Furthermore, research indicates that HKla is influenced by glucose metabolism and lactate generation, exhibiting significant phenotypic variability in response to various environmental stimuli. In vitro experiments reveal that exogenous lactate and glucose can upregulate the expression of HKla and promote cardiac hypertrophy. Conversely, inhibition of lactate production using glycolysis inhibitor (2-DG), LDH inhibitor (oxamate) and LDHA inhibitor (GNE-140) reduces HKla levels and inhibits the development of cardiac hypertrophy. Collectively, these findings establish a pivotal role for H3K18la in pathological cardiac hypertrophy, offering a novel target for the treatment of this condition.


Asunto(s)
Cardiomegalia , Histonas , Ácido Láctico , Miocitos Cardíacos , Animales , Cardiomegalia/metabolismo , Cardiomegalia/patología , Histonas/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Miocitos Cardíacos/efectos de los fármacos , Ratones , Ácido Láctico/metabolismo , Procesamiento Proteico-Postraduccional , Modelos Animales de Enfermedad , Glucosa/metabolismo , Masculino , Lisina/metabolismo , Ratones Endogámicos C57BL , Glucólisis
2.
Plant J ; 116(1): 112-127, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37344994

RESUMEN

Although vacuolar phosphate transporters (VPTs) are essential for plant phosphorus adaptation, their role in Rhizobium-legume symbiosis is unclear. In this study, homologous genes of VPT1 (MtVPTs) were identified in Medicago truncatula to assess their roles in Rhizobium-legume symbiosis and phosphorus adaptation. MtVPT2 and MtVPT3 mainly positively responded to low and high phosphate, respectively. However, both mtvpt2 and mtvpt3 mutants displayed shoot phenotypes with high phosphate sensitivity and low phosphate tolerance. The root-to-shoot phosphate transfer efficiency was significantly enhanced in mtvpt3 but weakened in mtvpt2, accompanied by lower and higher root cytosolic inorganic phosphate (Pi) concentration, respectively. Low phosphate induced MtVPT2 and MtVPT3 expressions in nodules. MtVPT2 and MtVPT3 mutations markedly reduced the nodule number and nitrogenase activity under different phosphate conditions. Cytosolic Pi concentration in nodules was significantly lower in mtvpt2 and mtvpt3 than in the wildtype, especially in tissues near the base of nodules, probably due to inhibition of long-distance Pi transport and cytosolic Pi supply. Also, mtvpt2 and mtvpt3 could not maintain a stable cytosolic Pi level in the nodule fixation zone as the wildtype under low phosphate stress. These findings show that MtVPT2 and MtVPT3 modulate phosphorus adaptation and rhizobia-legume symbiosis, possibly by regulating long-distance Pi transport.


Asunto(s)
Medicago truncatula , Rhizobium , Fósforo/metabolismo , Simbiosis/genética , Nódulos de las Raíces de las Plantas/metabolismo , Rhizobium/fisiología , Fosfatos/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Verduras/metabolismo , Fijación del Nitrógeno/genética
3.
Small ; 20(38): e2400845, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38881161

RESUMEN

Na2Ti3O7-based anodes show great promise for Na+ storage in sodium-ion batteries (SIBs), though the effect of Na2Ti3O7 morphology on battery performance remains poorly understood. Herein, hydrothermal syntheses is used to prepare free-standing Na2Ti3O7 nanosheets or Na2Ti3O7 nanotubes on Ti foil substrates, with the structural and electrochemical properties of the resulting electrodes explored in detail. Results show that the Na2Ti3O7 nanosheet electrode (NTO NSs) delivered superior performance in terms of reversible capacity, rate capability, and especially long-term durability in SIBs compared to its nanotube counterpart (NTO NTs). Electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) investigations, combined with density functional theory calculations, demonstrated that the flexible 2D Na2Ti3O7 nanosheets are mechanically more robust than the rigid Na2Ti3O7 nanotube arrays during prolonged battery cycling, explaining the superior durability of the NTO NSs electrode. This work prompts the use of anodes based on Na2Ti3O7 nanosheets in the future development of high-performance SIBs.

4.
Small ; 20(42): e2403894, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38864207

RESUMEN

Theory-guided materials design is an effective strategy for designing catalysts with high intrinsic activity whilst minimizing the usage of expensive metals like platinum. As proof-of-concept, herein it demonstrates that using density functional theory (DFT) calculations and experimental validation that intermetallic PtCo3 alloy nanoparticles offer enhanced electrocatatalytic performance for the oxygen reduction reaction (ORR) compared to Pt nanoparticles. DFT calculations established that PtCo3(111) surfaces possess better intrinsic ORR activity compared to Pt(111) surfaces, owing to the synergistic action of adjacent Pt and Co active sites which optimizes the binding strength of ORR intermediates to boost overall ORR kinetics. With this understanding, a PtCo3/NC catalyst, comprising PtCo3 nanoparticles exposing predominantly (111) facets dispersed on an N-doped carbon support, is successfully fabricated. PtCo3/NC demonstrates a high specific activity (3.4 mA cm-2 mgPt -1), mass activity (0.67 A mgPt -1), and cycling stability for the ORR in 0.1 M KOH, significantly outperforming a commercial 20 wt.% Pt/C catalyst. Moreover, a zinc-air battery (ZAB) assembled with PtCo3/NC as the air-electrode catalyst delivered an open-circuit voltage of 1.47 V, a specific capacity of 775.1 mAh gZn -1 and excellent operation durability after 200 discharge/charge cycles, vastly superior performance to a ZAB built using commercial Pt/C+IrO2 as the air-electrode catalyst.

5.
Arch Microbiol ; 206(6): 273, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38772954

RESUMEN

Acid protease is widely used in industries such as food processing and feed additives. In the study, low frequency magnetic field (LF-MF) as an aid enhances acid protease production by Aspergillus niger (A. niger). The study assessed mycelial biomass, the enzymic activity of the acidic protease and underlying mechanism. At low intensities, alternating magnetic field (AMF) is more effective than static magnetic fields (SMF). Under optimal magnetic field conditions, acid protease activity and biomass increased by 91.44% and 16.31%, as compared with the control, respectively. Maximum 19.87% increase in enzyme activity after magnetic field treatment of crude enzyme solution in control group. Transcriptomics analyses showed that low frequency alternating magnetic field (LF-AMF) treatment significantly upregulated genes related to hydrolases and cell growth. Our results showed that low-frequency magnetic fields can enhance the acid protease production ability of A. niger, and the effect of AMF is better at low intensities. The results revealed that the effect of magnetic field on the metabolic mechanism of A. niger and provided a reference for magnetic field-assisted fermentation of A. niger.


Asunto(s)
Aspergillus niger , Campos Magnéticos , Péptido Hidrolasas , Aspergillus niger/enzimología , Aspergillus niger/genética , Péptido Hidrolasas/metabolismo , Péptido Hidrolasas/genética , Fermentación , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Biomasa , Micelio/enzimología , Micelio/crecimiento & desarrollo , Micelio/genética
6.
Arch Microbiol ; 206(10): 392, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39230673

RESUMEN

Numerous works have reported that magnetic fields serve as signals capable of influencing microbial metabolism. However, little is known about the effect of magnetic field on erythritol production by the model microorganism Yarrowia lipolytica (Y. lipolytica). Therefore, we investigated the effect of low-frequency alternating magnetic fields (LF-AMF) with different magnetic field intensities (0-1.5 mT) and different magnetic field treatment times (1-10 days) on the production of erythritol by Y. lipolytica -JZ204. The optimal treatment condition was 0.5 mT for 8 days. As a result, a maximal erythritol yield was achieved 63.74 g/L, the biomass was reached 37 g/L, and the specific erythritol yield per unit of biomass was 1.7227 g/g, which were 60.72%, 32.09%, and 24.85% higher than the control, respectively. We investigated the internal mechanism of magnetic fields impact by using transcriptomics and RT-qPCR technology. This study demonstrated the effectiveness of LF-AMF in enhancing erythritol production by Y. lipolytica JZ-204, providing insights for the application of magnetic field in assisting microbial fermentation and improving the synthesis of beneficial products.


Asunto(s)
Eritritol , Campos Magnéticos , Yarrowia , Yarrowia/metabolismo , Yarrowia/genética , Yarrowia/crecimiento & desarrollo , Eritritol/metabolismo , Eritritol/biosíntesis , Fermentación , Biomasa
7.
Inorg Chem ; 63(27): 12681-12689, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38922608

RESUMEN

The oxygen reduction reaction (ORR) plays a vital role in many next-generation electrochemical energy conversion and storage devices, motivating the search for low-cost ORR electrocatalysts possessing high activity and excellent durability. In this work, we demonstrate that iron-cobalt phosphide (FeCoP) nanoparticles encapsulated in a N-doped carbon framework (FeCoP@NC) represent a very promising catalyst for the ORR in alkaline media. The core-shell structured FeCoP@NC catalyst offered outstanding ORR activity with a half-wave potential (E1/2) of 0.86 V vs reversible hydrogen electrode (RHE) and excellent stability in a 0.1 M KOH electrolyte, outperforming commercial Pt/C and many recently reported noble-metal-free ORR electrocatalysts. The superiority of FeCoP@NC as an ORR electrocatalyst relative to Pt/C was further verified in prototype zinc-air batteries (ZABs), with the aqueous and flexible ZABs prepared using FeCoP@NC offering excellent stability, impressive open circuit voltages (1.56 and 1.44 V, respectively), and high maximum power densities (183.5 and 69.7 mW cm-2, respectively). Density functional theory calculations revealed that encapsulating FeCoP nanoparticles in N-doped carbon shells resulted in favorable electron penetration effects, which synergistically regulated the adsorption/desorption of ORR intermediates for optimal ORR performance while also boosting the electronic conductivity. Our findings offer valuable new insights for rational design of transition metal phosphide-based catalysts for the ORR and other electrochemical applications.

8.
J Immunol ; 208(3): 618-632, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35022270

RESUMEN

Sepsis is an acute life-threatening disorder associated with multiorgan dysfunction that remains the leading cause of death in intensive care units. As sepsis progresses, it causes prolonged immunosuppression, which results in sustained mortality, morbidity, and susceptibility to secondary infections. Using a mouse model of sepsis, we found that the long noncoding RNA HOTAIRM1 (HOXA transcript antisense RNA myeloid-specific 1) was highly expressed in mice during the late phase of sepsis. The upregulation of HOTAIRM1 was induced by Notch/Hes1 activation and, moreover, was critical for the formation of an immunosuppressive microenvironment. HOTAIRM1 induced T cell exhaustion by increasing the percentage of PD-1+ T cells and regulatory T cells, accompanied by elevated PD-L1. Blockade of either Notch/Hes1 signaling or HOTAIRM1 inhibited T cell exhaustion in late sepsis, having alleviated lung injury and improved survival of mice. Further mechanistic studies identified HOXA1 as a key transcription factor targeted by HOTAIRM1 to regulate PD-L1 expression in lung alveolar epithelial cells. These results implicated that the Notch/Hes1/HOTAIRM1/HOXA1/PD-L1 axis was critical for sepsis-induced immunosuppression and could be a potential target for sepsis therapies.


Asunto(s)
Tolerancia Inmunológica/inmunología , MicroARNs/genética , Sepsis/inmunología , Linfocitos T Reguladores/inmunología , Animales , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/metabolismo , Proteínas de Homeodominio/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Sepsis/microbiología , Factor de Transcripción HES-1/metabolismo , Factores de Transcripción/metabolismo
9.
J Appl Microbiol ; 135(9)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39264044

RESUMEN

AIMS: Heterologous expression of sulfur: quinone oxidoreductase (Sqr) from Halomonas mongoliensis JS01, which is responsible for oxidizing sulfide to elemental sulfur, in Thioalkalivibrio versutus (T. versutus) D301 improves desulfurization. METHODS AND RESULTS: We expressed sqr in T. versutus D301 by conjugative transfer and then assayed its desulfurization capacity in an airlift reactor and analyzed its transcriptome at -380 mV ORP. Our findings demonstrate that the D301-sqr+ strain, utilizing sodium sulfide as a sulfur source under optimal ORP conditions (-380 mV), achieved an elemental sulfur yield of 95%. This represents an 8% increase over the T. versutus D301. Moreover, the sodium sulfide utilization rate for D301-sqr+ showed a marked improvement [0.741 vs. 0.651 mmol∙(l·h)-1], with a concurrent increase in the rate of elemental sulfur production when compared to the T. versutus D301 (0.716 vs. 0.518 mmol ∙(l·h)-1). Transcriptome analysis revealed that the flavocytochrome c (fcc) and the sox system were differentially transcriptionally down-regulated in D301-sqr+ compared with the T. versutus D301. CONCLUSIONS: Heterologous expression of the gene sqr altered the transcription of related genes in T. versutus D301 sulfur oxidation pathway, increasing the yield of elemental sulfur and the rate of sulfur oxidation, and making D301-sqr+ more potential for industrial applications.


Asunto(s)
Azufre , Azufre/metabolismo , Halomonas/genética , Halomonas/metabolismo , Halomonas/enzimología , Sulfuros/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Oxidación-Reducción , Quinona Reductasas/metabolismo , Quinona Reductasas/genética , Reactores Biológicos
10.
Angew Chem Int Ed Engl ; 63(38): e202406126, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-38923075

RESUMEN

Aqueous zinc batteries based on the conversion-type sulfur cathodes are promising in energy storage system due to the high theoretical energy density, low cost, and good safety. However, the multi-electron solid-state intermediate conversion reaction of sulfur cathodes generally possess sluggish kinetics, which leads to lower discharge voltage and inefficient sulfur utilization, thus suppressing the practical energy density. Herein, sulfur nanoparticles derived from metal-organic frameworks confined in situ within electrospun fibers derived sulfur and nitrogen co-doped carbon nanofibers (S@S,N-CNF) composite, which possesses yolk-shell S@C nanostructure, is fabricated through successive sulfidation, pyrolysis, and sulfide oxidation processes, and served as a high-performance cathode material for Zn-S battery. The S and N dopants on carbon can collectively catalyse sulfur reduction reaction (SRR) by lowering energy barrier and accelerating kinetics to increase discharge voltage and specific capacity. Meanwhile, the yolk-shell S@C structure with spatially confined S nanoparticle yolks is beneficial to improve charge transfer and lower activation energy, thus further expediting SRR kinetics. Furthermore, extensive density functional theory (DFT) calculations reveal that S and N dual-doping can thermodynamically and dynamically reduce the energy barrier of rate-determining step (i.e., the transformation of *ZnS4 into *ZnS2) for the overall SRR, thereby significantly accelerating SRR kinetics.

11.
Angew Chem Int Ed Engl ; : e202417902, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39383300

RESUMEN

Single- and few-layer graphene-based thermal interface materials (TIMs) with extraordinary high-temperature resistance and ultra-high thermal conductivity are very essential to develop the next-generation integrated circuits. However, the function of the as-prepared graphene-based TIMs would undergo severe degradation when being transferred to chips, as the interface between the TIMs and chips possesses a very small interfacial thermal conductance. Here, a "2.5D" all-carbon interface containing rich covalent bonding, namely a sp2/sp3 hybrid interfaces is designed and realized by a plasma-assisted chemical vapor deposition with a function of ultra-rapid quenching. The interfacial thermal conductance of the 2.5D interface is excitingly very high, up to 110-117 MWm-2K-1 at graphene thickness of 12-25 nm, which is even more than 30% higher than various metal/diamond contacts, and orders of magnitude higher than the existing all-carbon contacts. Atomic-level simulation confirm the key role of the efficient heat conduction via covalent C-C bonds, and reveal that the covalent-based heat transport could contribute 85% to the total interfacial conduction at a hybridization degree of 22 at%. This study provides an efficient strategy to design and construct 2.5D all-carbon interfaces, which can be used to develop high performance all-carbon devices and circuits.

12.
Cancer Sci ; 114(1): 105-114, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36114749

RESUMEN

Lung cancer is one of the leading causes of death among cancer patients worldwide. Carbon-ion radiotherapy is a radical nonsurgical treatment with high local control rates and no serious adverse events. N6-methyladenosine (m6A) modification is one of the most common chemical modifications in eukaryotic messenger RNA (mRNA) and has important effects on the stability, splicing, and translation of mRNAs. Recently, the regulatory role of m6A in tumorigenesis has been recognized more and more. However, the dysregulation of m6A and its role in carbon-ion radiotherapy of non-small-cell lung cancer (NSCLC) remains unclear. In this study, we found that the level of methyltransferase-like 3 (METTL3) and its mediated m6A modification were elevated in NSCLC cells with carbon-ion radiotherapy. Knockdown of METTL3 in NSCLC cells impaired proliferation, migration, and invasion in vitro and in vivo. Moreover, we found that METTL3-mediated m6A modification of mRNA inhibited the decay of H2A histone family member X (H2AX) mRNA and enhanced its expression, which led to enhanced DNA damage repair and cell survival.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Metiltransferasas/genética , Metiltransferasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Carbono
13.
Analyst ; 148(3): 516-524, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36625356

RESUMEN

The trans-epithelial electrical resistance (TEER) is widely used to quantitatively evaluate cellular barrier function at the organ level in vitro. The measurement of the TEER in organ-on-chips (organ chips) plays a significant role in medical and pharmacological research. However, due to the limitation of the electrical equivalent model for organ chips, the existing TEER measurements usually neglect the changes of the TEER during cell proliferation, resulting in the low accuracy of the measurements. Here, we proposed a new whole-region model of the TEER and developed a real-time TEER measurement system that contains an organ chip with a plate electrode. A whole region circuit model considering the impedance of the non-cell covered region was also established, which enables TEER measurements to be independent of the changes in the cell covered region. The impedance of the non-cell covered region is here attributed to the resistance of the porous membrane. By combining the real-time measurement system and the whole region model, subtle changes in cellular activity during the proliferation stage were measured continuously every 6 minutes and a more sensitive TEER response was obtained. Furthermore, the TEER measurement accuracy was also verified by the real-time measurement of the TEER with stimulation using the permeability enhancer ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA). The obtained results indicated that the new proposed whole region model and the real-time measurement system have higher accuracy and greater sensitivity than the traditional model.


Asunto(s)
Células Epiteliales , Sistemas Microfisiológicos , Impedancia Eléctrica , Línea Celular , Proliferación Celular
14.
Analyst ; 148(8): 1672-1681, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36939193

RESUMEN

With the development of advanced nanofabrication techniques over the past decades, different nanostructure-based plasmonic fiber-optic sensors have been developed and have presented a low limit of detection for various biomolecules. However, owing to both the dependence on complex equipment and the trade-off between the fabrication cost and sensing performance, nanostructured plasmonic fiber-optic sensors are rarely used outside laboratories. To facilitate wider application of the plasmonic fiber-optic sensors, a parylene-mediated hybrid plasmonic-photonic cavity-based sensor was developed. Compared with a similar plasmonic sensor which only works in the plasmonic mode, the proposed hybrid sensor shows a higher reproducibility (CV < 2.5%) due to its resistance to fabrication variations. Meanwhile, a self-referenced detection mechanism and a novel miniaturized system were developed to adapt to the hybrid resonance sensor. The entire system only has a weight of 263 g, and a size of 12 cm × 10 cm × 8 cm, and is especially suitable for outdoor applications in a handheld manner. In experiments, a high refractive index sensitivity of 3.148 RIU-1 and real-time biomolecule monitoring at nanomolar concentrations were achieved by the proposed system, further confirming the potential of the miniaturized system as a candidate for point-of-care health diagnostics outside laboratories.


Asunto(s)
Técnicas Biosensibles , Tecnología de Fibra Óptica , Tecnología de Fibra Óptica/instrumentación , Técnicas Biosensibles/instrumentación , Reproducibilidad de los Resultados , Oro , Nanopartículas del Metal
15.
BMC Neurol ; 23(1): 163, 2023 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-37087440

RESUMEN

OBJECTIVES: This study aims to discuss the availability of robot-assisted percutaneous balloon compression (PBC) for trigeminal neuralgia (TN) and share our preliminary experiences. METHODS: Patients with TN who underwent robot-assisted PBC from June to September 2022 were enrolled. We designed a fixing plug for robot-assisted PBC, three-dimensional structured light registration was used, puncture trajectory was the line connects the medial third of inner and outer aperture of foramen ovale. Numerical Rating Scale (NRS), Barrow Neurological Institute (BNI) pain and numbness intensity score were used to evaluate the facial pain and numbness. RESULTS: Eventually, nine patients were enrolled, the structured light registrations were successfully finished in all patients with a mean registration error of 0.68 mm. All the punctures of foramen ovales were successfully done one-time. Of note, the balloons were all got pear-shaped followed by 150 to 180 s compression. Though, postoperatively, all the patients complained of facial numbness and four patients suffered from transient masseter weakness, all patients got fully or mostly pain relief. It should be noted that is the numbness and weakness gradually relieved during follow-up. CONCLUSION: Three-dimensional structured light registration and robot assisted PBC is an effective choice for patients with TN. Extension line between the medial third of the inner and outer aperture of foramen ovale might be a safe and effective puncture trajectory to this procedure.


Asunto(s)
Robótica , Neuralgia del Trigémino , Humanos , Neuralgia del Trigémino/cirugía , Hipoestesia , Manejo del Dolor/métodos , Dolor Facial , Resultado del Tratamiento , Estudios Retrospectivos
16.
Nanotechnology ; 35(9)2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37995375

RESUMEN

Polyethylene glycol (PEG) is widely used as a phase change material (PCM) in thermal energy storage systems due to its high latent heat and chemical stability. However, practical application has been hindered by its low thermal conductivity and leakage issues. Therefore, developing shape-stable high thermal conductivity PCM is of great importance. In this study, new shape-stable composite PCM with high thermal conductivity and leak-prevention capabilities were designed. The porous carbon skeleton of diamond foam (DF) and dual-3D carbon nanotube-diamond foam (CDF) were prepared using the microwave plasma chemical vapor deposition method. The composite materials (DF/PEG and CDF/PEG) were produced by vacuum impregnation with PEG and skeletons. The results showed that CDF/PEG had the highest thermal conductivity, measuring 2.30 W·m-1·K-1, which is 707% higher than that of pure PEG. The employing of 3D networks of CNTs, which can improve the phonon mean free path in DF/PEG (1.79 W·m-1·K-1) while reducing phonon dispersion.The phonon vibration of dual-3D CDF plays an important role in heat transfer. PEG was physically absorbed and well-distributed in CDF, alleviating leakage of liquid PEG. The weight loss of CDF/PEG was only 25% at 70 °C for 120 s. Using CDF is an attractive and efficient strategy to increase the heat transfer of PEG and improve heat storage efficiency, alleviate the problem of poor shape-stability.

17.
Thromb J ; 21(1): 67, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328882

RESUMEN

Neutrophil extracellular traps (NETs) as special release products of neutrophils have received extensive attention. They are composed of decondensed chromatin and coated with nucleoproteins, including histones and some granulosa proteins. NETs can form a network structure to effectively capture and eliminate pathogens and prevent their spread. Not only that, recent studies have shown that NETs also play an important role in venous thrombosis. This review provides the most important updated evidence regarding the mechanism of NETs formation and the role of NETs in the process of venous thrombosis. The potential prophylactic and therapeutic value of NETs in venous thrombotic disease will also be discussed.

18.
Neuromodulation ; 26(8): 1714-1723, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36272897

RESUMEN

OBJECTIVES: This research analyzed the effect of surgical positioning on postoperative pneumocephalus and assessed additional potential risk factors of pneumocephalus in subthalamic nucleus (STN) deep brain stimulation (DBS) for Parkinson disease (PD). MATERIALS AND METHODS: In this study, 255 consecutive patients with PD who received bilateral STN DBS under general anesthesia were retrospectively included. Of these, 180 patients underwent surgery with their heads in an elevated position, and 75 patients underwent surgery in a supine position. The postoperative pneumocephalus volume was compared between the two groups. Other potential risk factors for pneumocephalus also were analyzed. RESULTS: The mean pneumocephalus volume for the group with elevated-head positioning (16.76 ± 15.23 cm3) was greater than for the supine group (3.25 ± 8.78 cm3) (p < 0.001). Multivariable analysis indicated that the pneumocephalus volume was related to surgical positioning, lateral trajectory angle, intraoperative mean arterial pressure (MAP), microelectrode recording (MER) passage number, brain atrophy degree, and the anterior trajectory angle. No correlation was found between pneumocephalus and age, sex, duration of PD, surgery length, or intracranial volume. In the subgroup analysis, the pneumocephalus volume exhibited a negative correlation with intraoperative MAP (r = -0.210, p = 0.005) and positive correlations with degree of brain atrophy (r = 0.242, p = 0.001) and MER passage number (r = 0.184, p = 0.014) in the elevated-head group. Specifically, an MER passage number > 3 was a significant risk factor for pneumocephalus in the elevated-head group. A positive correlation was observed between the pneumocephalus volume and the lateral trajectory angle in both groups (elevated-head positioning, r = 0.153, p = 0.041; supine positioning, r = 0.546, p < 0.001). CONCLUSIONS: In patients with PD who were anesthetized and receiving STN DBS, supine positioning reduced pneumocephalus volume compared with patients with PD receiving STN DBS with their heads elevated. The pneumocephalus volume was negatively correlated with intraoperative MAP and positively correlated with the degree of brain atrophy, the lateral trajectory angle, and the MER passage number.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson , Neumocéfalo , Núcleo Subtalámico , Humanos , Enfermedad de Parkinson/cirugía , Núcleo Subtalámico/diagnóstico por imagen , Núcleo Subtalámico/cirugía , Estudios Retrospectivos , Estimulación Encefálica Profunda/efectos adversos , Neumocéfalo/diagnóstico por imagen , Neumocéfalo/etiología , Microelectrodos , Atrofia/etiología
19.
J Environ Manage ; 347: 119107, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37801947

RESUMEN

Spent selective catalytic reduction (SCR) catalysts are environmentally hazardous and resource-enriching. In this work, V, W, and As in a spent SCR catalyst was extracted by alkali pressure leaching. Results showed that the V, W, and As were loaded on the anatase TiO2 crystal grains as amorphous oxides. The optimum pressure leaching conditions were NaOH concentration of 20 wt%, reaction temperature of 180 °C, reaction time of 120 min, L/S of 10 mL/g, and stirring speed of 300 rpm. The leaching efficiency of W, V, and As reached 98.83%, 100%, and 100%, respectively. The experiment revealed the preferential leaching of V and As rather than W, and the leaching mechanisms of V, W, and As were studied through experiment and density functional theory (DFT). The leaching kinetics of W conformed to a variant of the shrinking core model and the leaching process of W is controlled by both chemical reactions and diffusion processes. During the leaching process, Na2Ti2O4(OH)2 product powder layer was generated, which affects the mass transfer of W. The destruction of the TiO2 skeleton in the spent SCR catalyst is essential for adequate W extraction, especially for the extraction of W embedded in the TiO2 lattice. The DFT simulation result indicated that the V and As loaded onto the TiO2 support are easier to absorb hydroxide ions rather than W, and the leaching reaction energy of V and As was lower than W, As, and V has leaching priority over the leaching of W. Furthermore, an anatase TiO2 photocatalyst with the {001} crystal surface exposed was successfully prepared from the alkali pressure leaching residue. This work provides theoretical support for the metal leaching and utilization of spent SCR catalysts via alkali pressure leaching.


Asunto(s)
Álcalis , Titanio , Álcalis/química , Titanio/química , Metales , Óxidos/química , Catálisis
20.
Molecules ; 28(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38067583

RESUMEN

Ginseng residue is a by-product stemming from the commercial extraction of ginsenosides. To assess the disparities between ginseng residue and ginseng tablet, we employed the ultra-high-performance liquid chromatography-quadrupole time-of-flight/mass spectrometry (UPLC-Q-TOF/MS) technique for sample analysis. The analyses revealed the presence of 39 compounds in both ginseng residue and ginseng tablets. Subsequently, the contents of total ginsenosides and total ginseng polysaccharides in the ginseng residue and ginseng tablet were determined. The results indicate that while only a small fraction of ginsenosides remained in the ginseng residue, a significant amount of polysaccharides was retained. Furthermore, our evaluation encompassed the antioxidant activities of both ginseng residue and ginseng tablets. Notably, ginseng residue exhibited robust antioxidant effects, thereby showcasing its potential for recycling as a functional food raw material.


Asunto(s)
Ginsenósidos , Panax , Cromatografía Líquida de Alta Presión/métodos , Panax/química , Ginsenósidos/química , Polisacáridos , Comprimidos
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