Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 327
Filtrar
Más filtros

Base de datos
Tipo del documento
Intervalo de año de publicación
1.
J Orthop Surg Res ; 19(1): 421, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39034400

RESUMEN

BACKGROUND: Cellular senescence features irreversible growth arrest and secretion of multiple proinflammatory cytokines. Cyclic GMP-AMP synthase (cGAS) detects DNA damage and activates the DNA-sensing pathway, resulting in the upregulation of inflammatory genes and induction of cellular senescence. This study aimed to investigate the effect of cGAS in regulating senescence of nucleus pulposus (NP) cells under inflammatory microenvironment. METHODS: The expression of cGAS was evaluated by immunohistochemical staining in rat intervertebral disc (IVD) degeneration model induced by annulus stabbing. NP cells were harvested from rat lumbar IVD and cultured with 10ng/ml IL-1ß for 48 h to induce premature senescence. cGAS was silenced by cGAS specific siRNA in NP cells and cultured with IL-1ß. Cellular senescence was evaluated by senescence-associated beta-galactosidase (SA-ß-gal) staining and flow cytometry. The expression of senescence-associated secretory phenotype including IL-6, IL-8, and TNF-a was evaluated by ELISA and western blotting. RESULTS: cGAS was detected in rat NP cells in cytoplasm and the expression was significantly increased in degenerated IVD. Culturing in 10ng/ml IL-1ß for 48 h induced cellular senescence in NP cells with attenuation of G1-S phase transition. In senescent NP cells the expression of cGAS, p53, p16, NF-kB, IL-6, IL-8, TNF-α was significantly increased while aggrecan and collagen type II was reduced than in normal NP cells. In NP cells with silenced cGAS, the expression of p53, p16, NF-kB, IL-6, IL-8, and TNF-α was reduced in inflammatory culturing with IL-1ß. CONCLUSION: cGAS was increased by NP cells in degenerated IVD promoting cellular senescence and senescent inflammatory phenotypes. Targeting cGAS may alleviate IVD degeneration by reducing NP cell senescence.


Asunto(s)
Senescencia Celular , Degeneración del Disco Intervertebral , Nucleotidiltransferasas , Núcleo Pulposo , Ratas Sprague-Dawley , Senescencia Celular/fisiología , Animales , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patología , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/metabolismo , Nucleotidiltransferasas/metabolismo , Nucleotidiltransferasas/genética , Células Cultivadas , Ratas , Masculino , Inflamación/metabolismo , Inflamación/patología , Interleucina-1beta/metabolismo
2.
Acc Chem Res ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042917

RESUMEN

ConspectusLewis π acids, particularly high-valent transition metals with vacant orbitals, can coordinate with unsaturated compounds such as alkynes and alkenes by means of π-bonding. The coordination enhances the electrophilicity of the bound compounds, thereby facilitating reactions─such as nucleophilic addition─that take place at the ligated carbon-carbon multiple bonds. This activation phenomenon occurs at the ligand rather than at the metal atom, and it has been extensively utilized in the development of catalytic methods. In addition to alkynes and alkenes, aromatic compounds featuring a phenyl ring can be activated by an electrophilic transition-metal unit (e.g., Cr(CO)3, [Mn(CO)3]+, [CpFe]+, or [CpRu]+, where Cp = cyclopentadienyl) through π coordination. Over the past several decades, remarkable advances have been achieved in the development of reactions occurring on bound arenes, capitalizing on the highly electron-withdrawing nature of these transition-metal units and on the thermodynamic stability of η6-arene complexes. A prime example is the extension of nucleophilic aromatic substitution (SNAr) reactions to electron-neutral and -rich halobenzenes. Such arenes, which are normally inert to classical SNAr, can undergo sequences involving complex formation, substitution, and complex decomposition. Despite the successes achieved through the utilization of preformed complexes, the application of reversible arene coordination to catalytic systems has seen only limited progress. Consequently, in π-coordination activation, transition-metal units are commonly considered to be components of bound arene complexes rather than π-acid catalysts.In this Account, we summarize our recent research on catalytic SNAr reactions of halobenzenes and phenols enabled by reversible π-coordination of the arenes with electrophilic Ru or Rh catalysts, which we refer to as arenophilic π-acids. First, we developed a method for SNAr amination of fluorobenzenes with catalysis by a Ru(II) complex with a hemilabile P,O-bidentate ligand. The use of the hemilabile ligand significantly enhanced catalytic efficiency, allowing electron-rich and -neutral arenes to undergo amination without the need of excess fluorobenzenes. In a subsequent study of hydroxylation and alkoxylation reactions, we found that Rh(III) catalysts bearing a Cp-type ligand had a substantial activating effect. In addition, by isolating an η5 complex as the reaction intermediate, we obtained evidence in support of the long-standing hypothesis that SNAr of η6-arene complexes proceeds via a stepwise mechanism. Next, we extended the Rh-catalyzed SNAr to chloro- and bromobenzenes, which are abundant and readily available but are less reactive than corresponding fluorides toward SNAr. When the weakly nucleophilic alcohol hexafluoroisopropanol was used as a reaction partner, we were able to synthesize hexafluoroisopropyl aryl ethers, which are challenging to obtain by means of conventional approaches. Beyond halobenzenes, we successfully applied π-coordination strategy to achieve umpolung substitution reactions of phenols, which are typically nucleophilic. We found that an arenophilic Rh or Ru catalyst activated the phenol ring by π coordination instead of κ-O coordination, generating transient η5-phenoxo complexes that subsequently underwent carbonyl-amine condensation to produce anilines without the need for an exogenous oxidant or reductant. We anticipate that our research on catalyst development and reactions involving π-coordination activation will facilitate further advances in the application of arenophilic π acids.

3.
Adv Mater ; : e2406711, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046064

RESUMEN

Constructing well-defined active multisites is an effective strategy to break linear scaling relationships to develop high-efficiency catalysts toward multiple-intermediate reactions. Here, dual-intermetallic heterostructure composed of tungsten-bridged Co3W and WNi4 intermetallic compounds seamlessly integrated on hierarchical nanoporous nickel skeleton is reported as a high-performance nonprecious electrocatalyst for alkaline hydrogen evolution and oxidation reactions. By virtue of interfacial tungsten atoms configuring contiguous multisites with proper adsorptions of hydrogen and hydroxyl intermediates to accelerate water dissociation/combination and column-nanostructured nickel skeleton facilitating electron and ion/molecule transportations, nanoporous nickel-supported Co3W-WNi4 heterostructure exhibits exceptional hydrogen electrocatalysis in alkaline media, with outstanding durability and impressive catalytic activities for hydrogen oxidation reaction (geometric exchange current density of ≈6.62 mA cm-2) and hydrogen evolution reaction (current density of ≈1.45 A cm-2 at overpotential of 200 mV). Such atom-ordered intermetallic heterostructure alternative to platinum group metals shows genuine potential for hydrogen production and utilization in hydroxide-exchange-membrane water electrolyzers and fuel cells.

4.
Huan Jing Ke Xue ; 45(6): 3142-3152, 2024 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-38897738

RESUMEN

Groundwater contaminants pose a great threat to water safety and human health. Therefore, in this study, the traditional hazard assessment method was improved and a comprehensive system covering hazard assessment, screening, and characterization by combining the toxicological priority index (Tox Pi) framework; absorption, distribution, metabolism, and excretory (ADME) analysis; and bipartite network analysis was constructed. Then, the system was applied to hazard assessment and toxic pollutants screening from the 234 hydrophobic organic contaminants (HOCs) identified in the groundwater of Beijing. First, the top 20 pollutants with hazard potential were screened out using the Tox Pi method. Subsequently, 17 high-priority HOCs were further identified based on the ADME property analysis. Then, the molecular targets of these 17 high-priority HOCs were characterized through systematic bipartite network analysis. Finally, ten HOCs with high hazard were screened through correlation and weighted average analysis, and it was revealed that their toxic effects were mainly concentrated in the endocrine-disrupting effect, carcinogenic effect, and genetic toxicity. This study provides technical support for the prevention of regional groundwater contaminants.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Agua Subterránea/análisis , Monitoreo del Ambiente/métodos , Beijing , Sustancias Peligrosas/análisis , Compuestos Orgánicos/análisis , Medición de Riesgo
5.
Huan Jing Ke Xue ; 45(6): 3270-3283, 2024 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-38897750

RESUMEN

This study aimed to investigate the impact of spatiotemporal changes in land use on ecosystem carbon storage. The study analyzed the spatiotemporal changes in carbon storage in the study area based on land use data from five periods (1985, 1995, 2005, 2015, and 2020) using the InVEST model. The PLUS model was used to predict land use changes in the study area under four different scenarios (natural development, farmland protection, ecological protection, and double protection of farmland and ecology) in 2035, and the ecosystem carbon storage under different scenarios was estimated. The results of the study indicated that the farmland in the area under investigation had been decreasing consistently from 1985 to 2020, with a more rapid rate of change observed between 2015 and 2020. During this period, the overall dynamic attitude towards land use reached 34.62 %. Additionally, the carbon storage in the area showed a decreasing trend over the years, with a decrease of 1.55×105 t from 1985 to 2020. Between 2005 and 2015, the carbon storage showed a decrease of 1.22×105 t, with an average annual decrease of 1.22×104 t. The areas with higher carbon storage were located in the eastern part of the study area, whereas areas with lower carbon storage were found in the central and northwestern parts. Although the proportion of carbon storage in farmland decreased from 66.89 % to 57.73 %, farmland remained the most important carbon pool in the study area. The conversion of other land use types to grassland and forestland was advantageous for increasing ecosystem carbon storage. Finally, the study projected that by 2035, the carbon storage in the natural development scenario, the farmland protection scenario, the ecological protection scenario, and the dual protection scenario would be 81.77×105, 82.45×105, 82.82×105, and 82.51×105 t, respectively.

6.
Fundam Res ; 4(1): 131-139, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38933849

RESUMEN

Solar-driven CO2-to-fuel conversion assisted by another major greenhouse gas CH4 is promising to concurrently tackle energy shortage and global warming problems. However, current techniques still suffer from drawbacks of low efficiency, poor stability, and low selectivity. Here, a novel nanocomposite composed of interconnected Ni/MgAlO x nanoflakes grown on SiO2 particles with excellent spatial confinement of active sites is proposed for direct solar-driven CO2-to-fuel conversion. An ultrahigh light-to-fuel efficiency up to 35.7%, high production rates of H2 (136.6 mmol min-1g- 1) and CO (148.2 mmol min-1g-1), excellent selectivity (H2/CO ratio of 0.92), and good stability are reported simultaneously. These outstanding performances are attributed to strong metal-support interactions, improved CO2 absorption and activation, and decreased apparent activation energy under direct light illumination. MgAlO x @SiO2 support helps to lower the activation energy of CH* oxidation to CHO* and improve the dissociation of CH4 to CH3* as confirmed by DFT calculations. Moreover, the lattice oxygen of MgAlO x participates in the reaction and contributes to the removal of carbon deposition. This work provides promising routes for the conversion of greenhouse gasses into industrially valuable syngas with high efficiency, high selectivity, and benign sustainability.

7.
J Cell Mol Med ; 28(11): e18443, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38837873

RESUMEN

The human auricle has a complex structure, and microtia is a congenital malformation characterized by decreased size and loss of elaborate structure in the affected ear with a high incidence. Our previous studies suggest that inadequate cell migration is the primary cytological basis for the pathogenesis of microtia, however, the underlying mechanism is unclear. Here, we further demonstrate that microtia chondrocytes show a decreased directional persistence during cell migration. Directional persistence can define a leading edge associated with oriented movement, and any mistakes would affect cell function and tissue morphology. By the screening of motility-related genes and subsequent confirmations, active Rac1 (Rac1-GTP) is identified to be critical for the impaired directional persistence of microtia chondrocytes migration. Moreover, Rho guanine nucleotide exchange factors (GEFs) and Rho GTPase-activating proteins (GAPs) are detected, and overexpression of Tiam1 significantly upregulates the level of Rac1-GTP and improves directional migration in microtia chondrocytes. Consistently, decreased expression patterns of Tiam1 and active Rac1 are found in microtia mouse models, Bmp5se/J and Prkralear-3J/GrsrJ. Collectively, our results provide new insights into microtia development and therapeutic strategies of tissue engineering for microtia patients.


Asunto(s)
Movimiento Celular , Condrocitos , Microtia Congénita , Proteína 1 de Invasión e Inducción de Metástasis del Linfoma-T , Proteína de Unión al GTP rac1 , Animales , Femenino , Humanos , Masculino , Ratones , Condrocitos/metabolismo , Condrocitos/citología , Microtia Congénita/metabolismo , Microtia Congénita/genética , Microtia Congénita/patología , Modelos Animales de Enfermedad , Proteína de Unión al GTP rac1/metabolismo , Proteína 1 de Invasión e Inducción de Metástasis del Linfoma-T/metabolismo , Proteína 1 de Invasión e Inducción de Metástasis del Linfoma-T/genética
8.
ACS Nano ; 18(28): 18560-18571, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38941591

RESUMEN

High-performance thermal interface materials (TIMs) are highly desired for high-power electronic devices to accelerate heat dissipation. However, the inherent trade-off conflict between achieving high thermal conductivity and excellent compliance of filler-enhanced TIMs results in the unsatisfactory interfacial heat transfer efficiency of existing TIM solutions. Here, we report the graphene fiber (GF)-based elastic TIM with metal-level thermal conductivity via mechanical-electric dual-field synergistic alignment engineering. Compared with state-of-the-art carbon fiber (CF), GF features both superb high thermal conductivity of ∼1200 W m-1 K-1 and outstanding flexibility. Under dual-field synergistic alignment regulation, GFs are vertically aligned with excellent orientation (0.88) and high array density (33.5 mg cm-2), forming continuous thermally conductive pathways. Even at a low filler content of ∼17 wt %, GF-based TIM demonstrates extraordinarily high through-plane thermal conductivity of up to 82.4 W m-1 K-1, exceeding most CF-based TIMs and even comparable to commonly used soft indium foil. Benefiting from the low stiffness of GF, GF-based TIM shows a lower compressive modulus down to 0.57 MPa, an excellent resilience rate of 95% after compressive cycles, and diminished contact thermal resistance as low as 7.4 K mm2 W-1. Our results provide a superb paradigm for the directed assembly of thermally conductive and flexible GFs to achieve scalable and high-performance TIMs, overcoming the long-standing bottleneck of mechanical-thermal mismatch in TIM design.

9.
PLoS One ; 19(6): e0304972, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38905170

RESUMEN

Several studies have reported the efficacy of traditional Chinese medicine (TCM) for central serous chorioretinopathy (CSC), while some ophthalmologists are concerned that TCM may be a risk factor for CSC as some chinese herbs contain hormonal ingredients. This study aimed to evaluate the efficacy and safety of TCM in treating patients with CSC. Randomized controlled trials (RCTs) and observational studies of TCM for CSC were searched up to July 10, 2023 on the following biological databases without language and publication time restrictions: PubMed, Ovid Medline, Embase, Cochrane Library, The Chinese National Knowledge Infrastructure Database (CNKI), Technology Periodical Database (VIP), Wanfang, and Chinese Biomedical Literature Service System (SinoMed). Review Manager V.5.4.1 and Stata 14 software were used for data analysis. Finally, thirty-eight studies were finally included including 23 RCTs and 15 cohort studies. The meta-analysis showed that compared with the routine treatment alone, the combination of TCM can not only reduce the recurrence rate (OR = 0.29, 95% CI: 0.21,0.40; I2 = 0%) and central retinal thickness (CRT) (MD = - 35.63, 95% CI: - 45.96,-25.30; I2 = 89%) of CSC, but improve patients' best corrected visual acuity (BCVA) (SMD = 0.86, 95% CI: 0.62,1.11; I2 = 77%); additionally, it has no obvious side effects compared with routine treatment (OR = 0.72, 95% CI: 0.39,1.34; I2 = 10%). Overall, this study shows that the use of TCM does not increase the risk of CSC recurrence; on the contrary, the combination of TCM may reduce the recurrence of CSC and improve BCVA and CRT in patients with CSC compared with conventional treatment.


Asunto(s)
Coriorretinopatía Serosa Central , Medicina Tradicional China , Coriorretinopatía Serosa Central/tratamiento farmacológico , Humanos , Medicina Tradicional China/métodos , Medicamentos Herbarios Chinos/uso terapéutico , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Agudeza Visual/efectos de los fármacos
10.
J Org Chem ; 89(12): 8970-8984, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38850251

RESUMEN

Two substrate-controlled regiodivergent annulation protocols for 2,3-dioxopyrrolidines with 3-alkylidene oxindoles have been developed, which furnished a series of fused dihydropyrrolidone derivatives in high yields with excellent stereoselectivities. Plausible mechanistic pathways for both annulation reactions are proposed that [3 + 3] annulation reaction involves vinylogous Michael addition followed by intramolecular aldol cyclization, while [4 + 2] annulation reaction occurs through a vinylogous Michael addition and a subsequent intramolecular oxa-Michael cyclization.

11.
Cell Death Dis ; 15(6): 398, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844470

RESUMEN

In chronic kidney disease (CKD), renal fibrosis is an unavoidable result of various manifestations. However, its pathogenesis is not yet fully understood. Here, we revealed the novel role of Homeobox D10 (HOXD10) in CKD-related fibrosis. HOXD10 expression was downregulated in CKD-related in vitro and in vivo fibrosis models. UUO model mice were administered adeno-associated virus (AAV) containing HOXD10, and HOXD10 overexpression plasmids were introduced into human proximal tubular epithelial cells induced by TGF-ß1. The levels of iron, reactive oxygen species (ROS), lipid ROS, the oxidized glutathione/total glutathione (GSSG/GSH) ratio, malonaldehyde (MDA), and superoxide dismutase (SOD) were determined using respective assay kits. Treatment with AAV-HOXD10 significantly attenuated fibrosis and renal dysfunction in UUO model mice by inhibiting NOX4 transcription, ferroptosis pathway activation, and oxidative stress. High levels of NOX4 transcription, ferroptosis pathway activation and profibrotic gene expression induced by TGF-ß1/erastin (a ferroptosis agonist) were abrogated by HOXD10 overexpression in HK-2 cells. Moreover, bisulfite sequencing PCR result determined that HOXD10 showed a hypermethylated level in TGF-ß1-treated HK-2 cells. The binding of HOXD10 to the NOX4 promoter was confirmed by chromatin immunoprecipitation (ChIP) analysis and dual-luciferase reporter assays. Targeting HOXD10 may represent an innovative therapeutic strategy for fibrosis treatment in CKD.


Asunto(s)
Ferroptosis , Fibrosis , Proteínas de Homeodominio , NADPH Oxidasa 4 , Insuficiencia Renal Crónica , Ferroptosis/genética , Animales , NADPH Oxidasa 4/metabolismo , NADPH Oxidasa 4/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Humanos , Ratones , Insuficiencia Renal Crónica/patología , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/genética , Masculino , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Riñón/patología , Riñón/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo , Línea Celular
12.
Molecules ; 29(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731519

RESUMEN

Urban tailwater typically has a low carbon-to-nitrogen ratio and adding external carbon sources can effectively improve the denitrification performance of wastewater. However, it is difficult to determine the dosage of additional carbon sources, leading to insufficient or excessive addition. Therefore, it is necessary to prepare solid slow-release carbon source (SRC) materials to solve the difficulty in determining the dosage of carbon sources. This study selected two SRCs of slow-release carbon source 1 (SRC1) and slow-release carbon source 2 (SRC2), with good slow-release performance after static carbon release and batch experiments. The composition of SRC1 was: hydroxypropyl methylcellulose/disodium fumarate/polyhydroxy alkanoate (HPMC/DF/PHA) at a ratio of 3:2:4, with an Fe3O4 mass fraction of 3%. The composition of SRC2 was: HPMC/DF/PHA with a ratio of 1:1:1 and an Fe3O4 mass fraction of 3%. The fitted equations of carbon release curves of SRC1 and SRC2 were y = 61.91 + 7190.24e-0.37t and y = 47.92 + 8770.42e-0.43t, respectively. The surfaces of SRC1 and SRC2 had a loose and porous morphological structure, which could increase the specific surface area of materials and be more conducive to the adhesion and metabolism of microorganisms. The experimental nitrogen removal by denitrification with SRCs showed that when the initial total nitrogen concentration was 40.00 mg/L, the nitrate nitrogen (NO3--N) concentrations of the SRC1 and SRC2 groups on the 10th day were 2.57 and 2.66 mg/L, respectively. On the 20th day, the NO3--N concentrations of the SRC1 and SRC2 groups were 1.67 and 2.16 mg/L, respectively, corresponding to removal efficiencies of 95.83% and 94.60%, respectively. The experimental results indicated that SRCs had a good nitrogen removal effect. Developing these kinds of materials can provide a feasible way to overcome the difficulty in determining the dosage of carbon sources in the process of heterotrophic denitrification.

13.
J Am Chem Soc ; 146(23): 15833-15842, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38819396

RESUMEN

Ruthenium(II) complexes are known to form η6-arene complexes with benzene-containing compounds through π-coordination, a property extensively utilized to initiate reactions not typically observed with free arenes. A prime example is nucleophilic aromatic substitution, where ruthenium-complexed aryl halides undergo nucleophilic attack, allowing the direct synthesis of diverse aromatic compounds by displacing halides with nucleophiles. However, this activation relies on the electron-withdrawing effect of the Ru(II) species, as well as is hindered by the resistance of η6-arenes to arene exchange. In the previous pursuit of catalysis, the emphasis of ligand design has centered on promoting arene exchange. In this study, we extended the ruthenium activation strategy to umpolung substitution reactions of phenols. The amination proceeds through a direct condensation between phenols and amines, with a key intermediate identified as [bis(η5-phenoxo)Ru], which is in situ generated from a commercially available ruthenium catalyst. In comparison with the well-studied cyclopentadienyl (Cp) type ligands, we demonstrated that an η5-phenoxo motif, as a superior alternative to Cp, contributes to the amination of phenols in two crucial ways: its less electron-donating nature enhances the withdrawing effect of the ruthenium unit, facilitating substitution on the phenol complex; its distinctive behavior in arene exchange allows for conducting the amination with a catalytic amount of metal. Additionally, hydrogen bonding, wherein the phenoxo serves as the acceptor, was found to be important for the substitution. The versatility of this ruthenium-catalyzed amination was validated by performing reactions with a diverse array of phenols exhibiting various electronic properties, in combination with a wide range of primary amines. This work exemplifies the expansion of the scope of π-coordination activation in catalysis through innovative ligand development.

14.
JCI Insight ; 9(11)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713533

RESUMEN

Activation of brown adipose tissue (BAT) thermogenesis increases energy expenditure and alleviates obesity. Here we discover that histone methyltransferase suppressor of variegation 4-20 homolog 2 (Suv420h2) expression parallels that of Ucp1 in brown and beige adipocytes and that Suv420h2 knockdown significantly reduces - whereas Suv420h2 overexpression significantly increases - Ucp1 levels in brown adipocytes. Suv420h2 knockout (H2KO) mice exhibit impaired cold-induced thermogenesis and are prone to diet-induced obesity. In contrast, mice with specific overexpression of Suv420h2 in adipocytes display enhanced cold-induced thermogenesis and are resistant to diet-induced obesity. Further study shows that Suv420h2 catalyzes H4K20 trimethylation at eukaryotic translation initiation factor 4E-binding protein 1 (4e-bp1) promoter, leading to downregulated expression of 4e-bp1, a negative regulator of the translation initiation complex. This in turn upregulates PGC1α protein levels, and this upregulation is associated with increased expression of thermogenic program. We conclude that Suv420h2 is a key regulator of brown/beige adipocyte development and thermogenesis.


Asunto(s)
Adipocitos Beige , Tejido Adiposo Pardo , N-Metiltransferasa de Histona-Lisina , Ratones Noqueados , Obesidad , Termogénesis , Proteína Desacopladora 1 , Animales , Termogénesis/genética , Ratones , Adipocitos Beige/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Obesidad/metabolismo , Obesidad/genética , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 1/genética , Tejido Adiposo Pardo/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Adipocitos Marrones/metabolismo , Masculino , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Metabolismo Energético , Ratones Endogámicos C57BL
15.
BMC Genomics ; 25(1): 525, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807041

RESUMEN

BACKGROUND: The Rh blood group system is characterized by its complexity and polymorphism, encompassing 56 different antigens. Accurately predicting the presence of the C antigen using genotyping methods has been challenging. The objective of this study was to evaluate the accuracy of various genotyping methods for predicting the Rh C and to identify a suitable method for the Chinese Han population. METHODS: In total, 317 donors, consisting 223 D+ (including 20 with the Del phenotype) and 94 D- were randomly selected. For RHC genotyping, 48C and 109bp insertion were detected on the Real-time PCR platform and -292 substitution was analyzed via restriction fragment length polymorphism (RFLP). Moreover, the promoter region of the RHCE gene was sequenced to search for other nucleotide substitutions between RHC and RHc. Agreement between prediction methods was evaluated using the Kappa statistic, and comparisons between methods were conducted via the χ2 test. RESULTS: The analysis revealed that the 48C allele, 109bp insertion, a specific pattern observed in RFLP results, and wild-type alleles of seven single nucleotide polymorphisms (SNPs) were in strong agreement with the Rh C, with Kappa coefficients exceeding 0.8. However, there were instances of false positives or false negatives (0.6% false negative rate for 109bp insertion and 5.4-8.2% false positive rates for other methods). The 109bp insertion method exhibited the highest accuracy in predicting the Rh C, at 99.4%, compared to other methods (P values≤0.001). Although no statistical differences were found among other methods for predicting Rh C (P values>0.05), the accuracies in descending order were 48C (94.6%) > rs586178 (92.7%) > rs4649082, rs2375313, rs2281179, rs2072933, rs2072932, and RFLP (92.4%) > rs2072931 (91.8%). CONCLUSIONS: None of the methods examined can independently and accurately predict the Rh C. However, the 109bp insertion test demonstrated the highest accuracy for predicting the Rh C in the Chinese Han population. Utilizing the 109bp insertion test in combination with other methods may enhance the accuracy of Rh C prediction.


Asunto(s)
Pueblo Asiatico , Técnicas de Genotipaje , Polimorfismo de Nucleótido Simple , Sistema del Grupo Sanguíneo Rh-Hr , Humanos , Sistema del Grupo Sanguíneo Rh-Hr/genética , Pueblo Asiatico/genética , Técnicas de Genotipaje/métodos , China , Genotipo , Alelos , Polimorfismo de Longitud del Fragmento de Restricción , Frecuencia de los Genes , Regiones Promotoras Genéticas , Pueblos del Este de Asia
16.
Theranostics ; 14(6): 2427-2441, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38646649

RESUMEN

Background: MER proto-oncogene tyrosine kinase (MerTK) is a key receptor for efferocytosis, a process for the clearance of apoptotic cells. MerTK is mainly expressed in macrophages and immature dendritic cells. There are very limited reports focused on MerTK biology in aortic endothelial cells (ECs). It remains unclear for the role of blood flow patterns in regulating MerTK-mediated efferocytosis in aortic ECs. This study was designed to investigate whether endothelial MerTK and EC efferocytosis respond to blood flow patterns during atherosclerosis. Methods: Big data analytics, RNA-seq and proteomics combined with our in vitro and in vivo studies were applied to reveal the potential molecular mechanisms. Partial carotid artery ligation combined with AAV-PCSK9 and high fat diet were used to set up acute atherosclerosis in 4 weeks. Results: Our data showed that MerTK is sensitive to blood flow patterns and is inhibited by disturbed flow and oscillatory shear stress in primary human aortic ECs (HAECs). The RNA-seq data in HAECs incubated with apoptotic cells showed that d-flow promotes pro-inflammatory pathway and senescence pathway. Our in vivo data of proteomics and immunostaining showed that, compared with WT group, MerTK-/- aggravates atherosclerosis in d-flow areas through upregulation of endothelial dysfunction markers (e.g. IL-1ß, NF-κB, TLR4, MAPK signaling, vWF, VCAM-1 and p22phox) and mitochondrial dysfunction. Interestingly, MerTK-/-induces obvious abnormal endothelial thickening accompanied with decreased endothelial efferocytosis, promoting the development of atherosclerosis. Conclusions: Our data suggests that blood flow patterns play an important role in regulating MerTK-mediated efferocytosis in aortic ECs, revealing a new promising therapeutic strategy with EC efferocytosis restoration to against atherosclerosis.


Asunto(s)
Aorta , Aterosclerosis , Células Endoteliales , Fagocitosis , Tirosina Quinasa c-Mer , Tirosina Quinasa c-Mer/metabolismo , Tirosina Quinasa c-Mer/genética , Aterosclerosis/metabolismo , Aterosclerosis/patología , Aterosclerosis/fisiopatología , Humanos , Células Endoteliales/metabolismo , Animales , Aorta/metabolismo , Aorta/patología , Ratones , Apoptosis , Proto-Oncogenes Mas , Masculino , Ratones Endogámicos C57BL , Dieta Alta en Grasa , Células Cultivadas , Eferocitosis
18.
Orthop Surg ; 16(6): 1336-1343, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38654387

RESUMEN

OBJECTIVE: The reported date in the repeat surgical intervention for adolescent lumbar disc herniation (ALDH) after percutaneous endoscopic lumbar discectomy (PELD) was quite scarce. This study aims to introduce cases of repeat surgeries after PELD for ALDH and assess the incidence, chief causes, repeat surgery methods, and surgical outcomes of repeat surgeries after PELD for ALDH. METHODS: A retrospective multicenter observational study was conducted on patients undergoing repeat surgeries after PELD for ALDH at four tertiary referral hospitals from January 2014 through August 2022. The incidence of repeat surgeries, chief causes, strategies for repeat surgeries, and timing of repeat surgeries were recorded and analyzed. The clinical outcomes were evaluated by the Numeric Rating Scales (NRS) scores and the modified MacNab criteria. Statistical analyses were performed with the Wilcoxon signed-rank test. RESULTS: A total of 23 patients who underwent repeat surgeries after PELD for ALDH were included. The chief causes were re-herniation (homo-lateral re-herniation at the same level, new disc herniation of adjacent level). The repeat surgery methods were revision PELD, micro-endoscopic discectomy (MED), open discectomy and instrumented lumbar inter-body fusion. The NRS scores decreased significantly in follow-up evaluations and these scores demonstrated significant improvement at the last follow-up (p < 0.002). For the modified MacNab criteria, at the last follow-up, 18 patients (78.26%) had an excellent outcome, and the overall success rate was 86.95%. CONCLUSION: This study's data suggest that young patients who underwent repeat surgery improved significantly compared to baseline. The chief cause was re-herniation. Revision PELD was the main surgical procedure, which provides satisfactory clinical results in young patients who underwent repeat surgeries.


Asunto(s)
Discectomía Percutánea , Endoscopía , Desplazamiento del Disco Intervertebral , Vértebras Lumbares , Reoperación , Humanos , Desplazamiento del Disco Intervertebral/cirugía , Adolescente , Estudios Retrospectivos , Masculino , Femenino , Vértebras Lumbares/cirugía , Discectomía Percutánea/métodos , Endoscopía/métodos , Adulto Joven
19.
Adv Mater ; 36(26): e2403803, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38598181

RESUMEN

Aqueous zinc-ion batteries are attractive post-lithium battery technologies for grid-scale energy storage because of their inherent safety, low cost and high theoretical capacity. However, their practical implementation in wide-temperature surroundings persistently confronts irregular zinc electrodeposits and parasitic side reactions on metal anode, which leads to poor rechargeability, low Coulombic efficiency and short lifespan. Here, this work reports lamellar nanoporous Cu/Al2Cu heterostructure electrode as a promising anode host material to regulate high-efficiency and dendrite-free zinc electrodeposition and stripping for wide-temperatures aqueous zinc-ion batteries. In this unique electrode, the interconnective Cu/Al2Cu heterostructure ligaments not only facilitate fast electron transfer but work as highly zincophilic sites for zinc nucleation and deposition by virtue of local galvanic couples while the interpenetrative lamellar channels serving as mass transport pathways. As a result, it exhibits exceptional zinc plating/stripping behaviors in aqueous hybrid electrolyte of diethylene glycol dimethyl ether and zinc trifluoromethanesulfonate at wide temperatures ranging from 25 to -30 °C, with ultralow voltage polarizations at various current densities and ultralong lifespan of >4000 h. The outstanding electrochemical properties enlist full cell of zinc-ion batteries constructed with nanoporous Cu/Al2Cu and ZnxV2O5/C to maintain high capacity and excellent stability for >5000 cycles at 25 and -30 °C.

20.
Small ; : e2311509, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587968

RESUMEN

Developing robust non-platinum electrocatalysts with multifunctional active sites for pH-universal hydrogen evolution reaction (HER) is crucial for scalable hydrogen production through electrochemical water splitting. Here ultra-small ruthenium-nickel alloy nanoparticles steadily anchored on reduced graphene oxide papers (Ru-Ni/rGOPs) as versatile electrocatalytic materials for acidic and alkaline HER are reported. These Ru-Ni alloy nanoparticles serve as pH self-adaptive electroactive species by making use of in situ surface reconstruction, where surface Ni atoms are hydroxylated to produce bifunctional active sites of Ru-Ni(OH)2 for alkaline HER, and selectively etched to form monometallic Ru active sites for acidic HER, respectively. Owing to the presence of Ru-Ni(OH)2 multi-site surface, which not only accelerates water dissociation to generate reactive hydrogen intermediates but also facilitates their recombination into hydrogen molecules, the self-supported Ru90Ni10/rGOP hybrid electrode only takes overpotential of as low as ≈106 mV to deliver current density of 1000 mA cm-2, and maintains exceptional stability for over 1000 h in 1 m KOH. While in 0.5 m H2SO4, the Ru90Ni10/rGOP hybrid electrode exhibits acidic HER catalytic behavior comparable to commercially available Pt/C catalyst due to the formation of monometallic Ru shell. These electrochemical behaviors outperform some of the best Ru-based catalysts and make it attractive alternative to Pt-based catalysts toward highly efficient HER.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA