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1.
Chem Commun (Camb) ; 60(68): 9070-9073, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39101974

RESUMEN

Intermolecular annulation reactions of 1-naphthyl-1,3-indandiones with alkenes proceed efficiently in the presence of a copper catalyst to generate spirocarbocycle compounds. Various spirocyclic molecules bearing an all-carbon quaternary center could be obtained by this novel method with good yields, excellent regioselectivity, and good functional group tolerance. A radical mechanism is proposed based on the HRMS analysis results of control experiments.

2.
Front Psychol ; 15: 1403530, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39118845

RESUMEN

Introduction: This meta-analysis investigates the relationships between the Dark Triad personality traits (narcissism, Machiavellianism, and psychopathy) and mental toughness. Previous research has shown mixed results regarding the influence of these traits on mental toughness. The objective of this meta-analysis is to synthesize existing literature and provide a comprehensive understanding of how Dark Triad traits correlate with mental toughness. Methods: A comprehensive literature search was conducted in 7 databases, Data were extracted by correlation and analyzed using a random-effects model. Results: The results yielding 27 effect sizes with a total of 12,378 participants, revealed a significant moderate positive association between narcissism and mental toughness (r = 0.327, p < 0.001), suggesting that individuals with higher levels of narcissism tend to exhibit greater mental toughness. However, no significant associations were found between Machiavellianism (r = 0.023, p = 0.719) or psychopathy (r = -0.022, p = 0.625) and mental toughness. Discussion: The findings contribute to a more nuanced understanding of the Dark Triad traits and their differential associations with adaptive psychological constructs, highlighting the unique role of narcissism in mental toughness. This meta-analysis provides valuable insights for future research and practical applications in fostering adaptive aspects of narcissism while mitigating its potential maladaptive consequences.

3.
Chem Commun (Camb) ; 60(53): 6769-6772, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38864642

RESUMEN

A practical and effective palladium-catalyzed C-H activation/alkene insertion/annulation has been reported for the synthesis of furans and cyclopropanes from cyclic 1,3-diketones or 1,3-indandione and diverse alkenes, resulting in moderate to good yields. This protocol demonstrates excellent selectivity and is well-compatible with a wide range of alkene substrates, exhibiting exceptional regioselectivities, high efficiency, and good functional group tolerance.

4.
ACS Omega ; 9(22): 23542-23554, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38854559

RESUMEN

The dynamic load resulting from the fracture of extremely thick rock layers directly influences the surrounding rock layers within stopes and roadways, thereby inducing rockburst disasters. Hence, studying the tunnel floor's impact and ground pressure induced by dynamic load disturbance under extremely thick conglomerates is crucial. This study focuses on the 23130 working face of Yuejin Coal Mine as its engineering background. Initially, through similar simulation experiments, the impact characteristics of dynamic load disturbance positions under thick conglomerates on tunnel bottom damage are investigated. Building upon this foundation, finite element numerical simulation is employed to explore the further conglomerate thickness' impact on tunnel floor damage under dynamic load disturbance. Lastly, the accuracy of similar and numerical simulation results is validated by incorporating field examples. Findings reveal that dynamic load disturbance leads to an instantaneous increase in coal and rock mass acceleration in the roof and floor of roadways, followed by a decrease to an equilibrium state, thereby subjecting the interior to high static load conditions. The thickness of conglomerate in the overlying rock layer emerges as a crucial factor affecting tunnel floor rockburst incidents. With dynamic load disturbance, as conglomerate thickness increases, the stress concentration area of the tunnel floor gradually shifts to deeper rock strata. Effective control of tunnel floor rockbursts can be achieved by implementing support measures like anchor rods and cables and managing tunnel deformation and damage under dynamic loads. Dynamic load disturbance under extremely thick conglomerates emerges as a pivotal condition for inducing tunnel floor impact damage. This study provides a theoretical foundation for the safe excavation of similar mine tunnels and for implementing rockburst prevention and control measures.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38692393

RESUMEN

BACKGROUND: Internet gaming disorder (IGD) can lead to psychological problems and cause behavioral problems in individuals. Traditional interventions have been ineffective in treating IGD. Meanwhile, mindfulness meditation (MM) is an emerging method that has proven to be effective for treating psychiatric disorders. In this study, MM was used to intervene in IGD and to explore its neural mechanism. METHODS: Eighty participants were recruited through advertisements. Eventually, 61 completed the 1-month training (MM group, n = 31; progressive muscle relaxation [PMR] group, n = 30), including a pretest, 8 training sessions, and a posttest. Regional homogeneity and degree centrality were calculated, and the tests (pre- and post-) and group (MM and PMR) analysis of variance was performed. The overlapping results were obtained as region of interest for functional connectivity (FC) analyses. Behavioral data and neurotransmitter availability maps were correlated with FC. RESULTS: Compared with PMR, MM decreased the severity of addiction and game craving in IGD. Brain imaging results showed that the FC between and within the executive control and default mode networks/reward-related regions were enhanced. Significant negative correlations were observed between FC and dopamine receptor D2, dopamine transporter, and vesicular acetylcholine transporter. Significant positive correlations were observed between FCs and serotonin and aminobutyric acid receptors. CONCLUSIONS: This study confirmed the effectiveness of MM in treating IGD. MM altered the default mode and enhanced top-down control over game cravings. These findings were revealed by the correlations between brain regions and behavioral and biochemical effects. The results show the neural mechanism of MM in reducing IGD and lay the foundation for future research.


Asunto(s)
Ansia , Red en Modo Predeterminado , Función Ejecutiva , Trastorno de Adicción a Internet , Imagen por Resonancia Magnética , Meditación , Atención Plena , Humanos , Masculino , Atención Plena/métodos , Adulto Joven , Trastorno de Adicción a Internet/terapia , Trastorno de Adicción a Internet/fisiopatología , Ansia/fisiología , Función Ejecutiva/fisiología , Adulto , Femenino , Red en Modo Predeterminado/fisiopatología , Red en Modo Predeterminado/diagnóstico por imagen , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Conectoma , Adolescente
6.
Int J Rheum Dis ; 27(4): e15131, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38563679

RESUMEN

OBJECTIVE: To evaluate the incidence and associated factors of initial and recurrent severe infections in hospitalized patients with systemic lupus erythematosus (SLE). METHODS: SLE patients that first hospitalized between 2010 and 2021 were studied retrospectively and divided into SLE with and without baseline severe infection groups. The primary outcome was the occurrence of severe infection during follow-up. Cox regression models were used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for initial and recurrent severe infections. RESULTS: Among 1051 first hospitalized SLE patients, 164 (15.6%) had severe infection on admission. During a median follow-up of 4.1 years, 113 (10.8%) patients reached severe infection outcomes, including 27 with reinfection and 86 with initial severe infection (16.5% vs. 9.7%, p = .010). Patients with baseline severe infection had a higher cumulative incidence of reinfection (p = .007). After adjusting for confounding factors, renal involvement, elevated serum creatinine, hypoalbuminemia, cyclophosphamide, and mycophenolate mofetil treatment were associated with an increased risk of severe infection, especially initial severe infection. Low immunoglobulin, anti-dsDNA antibody positivity, and cyclophosphamide use significantly increased the risk of recurrent severe infection, with adjusted HR (95% CI) of 3.15 (1.22, 8.14), 3.60 (1.56, 8.28), and 2.14 (1.01, 5.76), respectively. Moreover, baseline severe infection and low immunoglobulin had a multiplicative interaction on reinfection, with adjusted RHR (95% CI) of 3.91 (1.27, 12.09). CONCLUSION: In this cohort of SLE, patients with severe infection had a higher risk of reinfection, and low immunoglobulin, anti-dsDNA antibody positivity, and cyclophosphamide use were independent risk factors for recurrent severe infection.


Asunto(s)
Lupus Eritematoso Sistémico , Reinfección , Humanos , Estudios Retrospectivos , Ciclofosfamida/efectos adversos , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/epidemiología , Factores de Riesgo , Inmunoglobulinas , China/epidemiología
7.
Materials (Basel) ; 17(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38612090

RESUMEN

In order to study the multi-mode damage and fracture mechanisms of thin-walled tubular parts with cross inner ribs (longitudinal and transverse inner ribs, LTIRs), the Gurson-Tvergaard-Needleman (GTN) model was modified with a newly proposed stress state function. Thus, tension damage and shear damage were unified by the new stress state function, which was asymmetric with respect to stress triaxiality. Tension damage dominated the modification, which coupled with the shear damage variable, ensured the optimal prediction of fractures of thin-walled tubular parts with LTIRs by the modified GTN model. This included fractures occurring at the non-rib zone (NRZ), the longitudinal rib (LIR) and the interface between the transverse rib (TIR) and the NRZ. Among them, the stripping of material from the outer surface of the tubular part was mainly caused by the shearing of built-up material in front of the rollers under a large wall thickness reduction (ΔT). Shear and tension deformation were the causes of fractures occurring at the NRZ, while axial tension under a large TIR interval (l) mainly resulted in fractures on LIRs. Fractures at the interface between the TIR and NRZ were due to the shearing applied by rib grooves and radial tension during the formation of ribs. This study can provide guidance for the manufacturing of high-performance aluminum alloy thin-walled tubular components with complex inner ribs.

8.
Inflamm Res ; 73(6): 1047-1068, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38622285

RESUMEN

BACKGROUND: Tumor immunotherapy brings new light and vitality to breast cancer patients, but low response rate and limitations of therapeutic targets become major obstacles to its clinical application. Recent studies have shown that CD24 is involved in an important process of tumor immune regulation in breast cancer and is a promising target for immunotherapy. METHODS: In this study, singleR was used to annotate each cell subpopulation after t-distributed stochastic neighbor embedding (t-SNE) methods. Pseudo-time trace analysis and cell communication were analyzed by Monocle2 package and CellChat, respectively. A prognostic model based on CD24-related genes was constructed using several machine learning methods. Multiple quantitative immunofluorescence (MQIF) was used to evaluate the spatial relationship between CD24+PANCK+cells and exhausted CD8+T cells. RESULTS: Based on the scRNA-seq analysis, 1488 CD24-related differential genes were identified, and a risk model consisting of 15 prognostic characteristic genes was constructed by combining the bulk RNA-seq data. Patients were divided into high- and low-risk groups based on the median risk score. Immune landscape analysis showed that the low-risk group showed higher infiltration of immune-promoting cells and stronger immune reactivity. The results of cell communication demonstrated a strong interaction between CD24+epithelial cells and CD8+T cells. Subsequent MQIF demonstrated a strong interaction between CD24+PANCK+ and exhausted CD8+T cells with FOXP3+ in breast cancer. Additionally, CD24+PANCK+ and CD8+FOXP3+T cells were positively associated with lower survival rates. CONCLUSION: This study highlights the importance of CD24+breast cancer cells in clinical prognosis and immunosuppressive microenvironment, which may provide a new direction for improving patient outcomes.


Asunto(s)
Neoplasias de la Mama , Antígeno CD24 , Microambiente Tumoral , Humanos , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/genética , Antígeno CD24/genética , Antígeno CD24/inmunología , Microambiente Tumoral/inmunología , Femenino , Pronóstico , Linfocitos T CD8-positivos/inmunología , Aprendizaje Automático , Multiómica
9.
Plant Cell Environ ; 47(7): 2510-2525, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38514902

RESUMEN

The micronutrient iron plays a crucial role in the growth and development of plants, necessitating meticulous regulation for its absorption by plants. Prior research has demonstrated that the transcription factor MxZR3.1 restricts iron absorption in apple rootstocks; however, the precise mechanism by which MxZR3.1 contributes to the regulation of iron homoeostasis in apple rootstocks remains unexplored. Here, MxMPK3-2, a protein kinase, was discovered to interact with MxZR3.1. Y2H, bimolecular fluorescence complementation and pull down experiments were used to confirm the interaction. Phosphorylation and cell semi-degradation tests have shown that MxZR3.1 can be used as a substrate of MxMPK3-2, which leads to the MxZR3.1 protein being more stable. In addition, through tobacco transient transformation (LUC and GUS) experiments, it was confirmed that MxZR3.1 significantly inhibited the activity of the MxHA2 promoter, while MxMPK3-2 mediated phosphorylation at the Ser94 site of MxZR3.1 further inhibited the activity of the MxHA2 promoter. It is tightly controlled to absorb iron during normal growth and development of apple rootstocks due to the regulatory effect of the MxMPK3-2-MxZR3.1 module on MxHA2 transcription level. Consequently, this research has revealed the molecular basis of how the MxMPK3-2-MxZR3.1 module in apple rootstocks controls iron homoeostasis by regulating the MxHA2 promoter's activity.


Asunto(s)
Homeostasis , Hierro , Malus , Proteínas de Plantas , Raíces de Plantas , Malus/metabolismo , Malus/genética , Fosforilación , Hierro/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulación de la Expresión Génica de las Plantas , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética
10.
Arthritis Rheumatol ; 76(7): 1096-1108, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38433594

RESUMEN

OBJECTIVE: The goal was to investigate the role and intracellular regulatory mechanisms of double-negative T (DNT) cells in the pathogenesis of systemic lupus erythematosus (SLE). METHODS: DNT cells were assessed in murine models, patients with SLE, and controls using flow cytometry (FCM). DNT cells from either resiquimod (R848) or vehicle-treated C57BL/6 (B6) mice were cultured with B cells from R848-treated mice to explore functions. Differential mechanistic target of rapamycin (mTOR) pathway signaling in DNT cells measured using FCM and quantitative polymerase chain reaction was validated by rapamycin inhibition. Candidate lipid metabolites detected using liquid chromatography with electrospray ionization mass spectrometry/mass spectrometry were functionally assessed in DNT cell cultures. RESULTS: DNT cells were markedly increased in both spontaneous and induced mouse lupus models and in patients with SLE. Expanded DNT cells from R848-treated B6 mice produced elevated interleukin (IL)-17A and IgG with increased germinal center B (GCB) cells. Expansion of DNT cells associated with activation of mTORC1 pathway that both IL-17A levels and the number of DNT cells exhibited dose-dependent reduction with rapamycin treatment. Lipidomics studies revealed differential patterns of lipid metabolites in T cells of R848-treated mice. Among candidate metabolites, elevated phosphatidic acid (PA) that was partially controlled by phospholipase D2 increased the expression of the mTORC1 downstream target p-S6 and positively expanded IL-17A-producing DNT cells. Similarly, elevated proportions of circulating DNT cells in patients with SLE correlated with disease activity and proteinuria, and IL-17A secretion was elevated after in vitro PA stimulation. CONCLUSION: The accumulation of PA in T cells could activate the mTORC1 pathway, promoting DNT cell expansion and IL-17A secretion, resulting in GCB cell abnormalities in lupus.


Asunto(s)
Interleucina-17 , Lupus Eritematoso Sistémico , Diana Mecanicista del Complejo 1 de la Rapamicina , Ácidos Fosfatidicos , Transducción de Señal , Animales , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/metabolismo , Interleucina-17/metabolismo , Ácidos Fosfatidicos/farmacología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones , Humanos , Ratones Endogámicos C57BL , Femenino , Modelos Animales de Enfermedad , Linfocitos T/metabolismo , Linfocitos T/inmunología
11.
Nanotechnology ; 35(26)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461553

RESUMEN

Nanofluids have excellent lubrication and high thermal conductivity. However, the agglomeration and sedimentation produced by the large surface energy of nanoparticles in base liquid threaten the long-term dispersion stability and impact the wide application of nanofluid. In this work, based on the self-assemble behavior and continuous network structure formed by low molecular weight organic gelator, the uniform clusters were formed through regulating the kinetics behavior in the gelling process. The dragging effect was demonstrated by oleic acid - sodium dodecyl sulfate (OA-SDS) bicomponent gelator and graphene oxide (GO) nanosheets. The results showed that GO nanofluids dispersed by OA-SDS were stable for more than 12 months. The well-dispersed GO nanofluid exhibited better anti-friction and anti-wear properties under both immersion and electrostatic minimum quantity lubrication conditions. Moreover, the lower contact angle, surface tension and droplet size of nanofluids after charging improved the wettability on the frictional interface. The GO adsorption film formed on the friction interface protected the tribochemical reaction film of iron oxide and prevented the occurrence of sintering of base oil.

12.
Fitoterapia ; 175: 105910, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38479619

RESUMEN

Three new indole alkaloid derivatives, fissindoalkas A-C (1-3) together with one known biogenetically related polysubstituted indole alkaloid (4) were isolated from the roots of Fissistigma oldhamii (Hemsl.) Merr. The structures of compounds 1-4 were elucidated using comprehensive spectroscopic methods. The inhibitory activities of compounds 1-4 against nitric oxide (NO) production induced by lipopolysaccharide (LPS) were evaluated in vitro using mouse macrophage RAW264.7 cells. Compounds 2 and 3 showed potent inhibitory activities on NO production with IC50 values of 2.52 ± 0.18 and 2.33 ± 0.16 µM. These results indicate that the discovery of indole alkaloid derivatives, from the roots of F. oldhamii, which show significant anti-inflammatory properties, could be of great importance to the research and for the development of novel natural anti-inflammatory agents.


Asunto(s)
Antiinflamatorios , Alcaloides Indólicos , Óxido Nítrico , Raíces de Plantas , Animales , Ratones , Células RAW 264.7 , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/química , Estructura Molecular , Óxido Nítrico/metabolismo , Raíces de Plantas/química , Alcaloides Indólicos/farmacología , Alcaloides Indólicos/aislamiento & purificación , Alcaloides Indólicos/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , China
13.
Oncol Lett ; 27(4): 161, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38449794

RESUMEN

Patients with advanced pancreatic cancer (PC) need a cost-effective treatment regimen. The present study was designed to compare the efficacy and safety of nab-paclitaxel plus S-1 (AS) and gemcitabine plus S-1 (GS) regimens in patients with chemotherapy-naïve advanced PC. In this open-label, multicenter, randomized study named AvGmPC, eligible patients with chemotherapy-naïve advanced PC were randomly assigned (1:1) to receive AS (125 mg/m2 nab-paclitaxel, days 1 and 8; 80-120 mg S-1, days 1-14) or GS (1,000 mg/m2 gemcitabine, days 1 and 8; 80-120 mg S-1, days 1-14). The treatment was administered every 3 weeks until intolerable toxicity or disease progression occurred. The primary endpoint was progression-free survival (PFS). Between December 2018 and March 2022, 101 of 106 randomized patients were treated and evaluated for analysis (AS, n=49; GS, n=52). As of the data cutoff, the median follow-up time was 11.37 months [95% confidence interval (CI), 9.31-13.24]. The median PFS was 7.16 months (95% CI, 5.19-12.32) for patients treated with AS and 6.41 months (95% CI, 3.72-8.84) for patients treated with GS (HR=0.78; 95% CI, 0.51-1.21; P=0.264). The AS regimen showed a slightly improved overall survival (OS; 13.27 vs. 10.64 months) and a significantly improved ORR (44.90 vs. 15.38%; P=0.001) compared with the GS regimen. In the subgroup analyses, PFS and OS benefits were observed in patients treated with the AS regimen who had KRAS gene mutations and high C-reactive protein (CRP) levels (≥5 mg/l). The most common grade ≥3 adverse events were neutropenia, anemia and alopecia in the two groups. Thrombocytopenia occurred more frequently in the GS group than in the AS group. While the study did not meet the primary endpoint, the response benefit observed for AS may be suggestive of meaningful clinical activity in this population. In particular, promising survival benefits were observed in the subsets of patients with KRAS gene mutations and high CRP levels, which is encouraging and warrants further investigation. This trial was retrospectively registered as ChiCTR1900024588 on July 18, 2019.

14.
Am J Respir Cell Mol Biol ; 70(5): 400-413, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38301267

RESUMEN

Newborns with intrauterine growth restriction (IUGR) have a higher likelihood of developing pulmonary arterial hypertension (PAH) in adulthood. Although there is increasing evidence suggesting that pericytes play a role in regulating myofibroblast transdifferentiation and angiogenesis in malignant and cardiovascular diseases, their involvement in the pathogenesis of IUGR-related pulmonary hypertension and the underlying mechanisms remain incompletely understood. To address this issue, a study was conducted using a Sprague-Dawley rat model of IUGR-related pulmonary hypertension. Our investigation revealed increased proliferation and migration of pulmonary microvascular pericytes in IUGR-related pulmonary hypertension, accompanied by weakened endothelial-pericyte interactions. Through whole-transcriptome sequencing, Ddx5 (DEAD-box protein 5) was identified as one of the hub genes in pericytes. DDX5, a member of the RNA helicase family, plays a role in the regulation of ATP-dependent RNA helicase activities and cellular function. MicroRNAs have been implicated in the pathogenesis of PAH, and microRNA-205 (miR-205) regulates cell proliferation, migration, and angiogenesis. The results of dual-luciferase reporter assays confirmed the specific binding of miR-205 to Ddx5. Mechanistically, miR-205 negatively regulates Ddx5, leading to the degradation of ß-catenin by inhibiting the phosphorylation of Gsk3ß at serine 9. In vitro experiments showed the addition of miR-205 effectively ameliorated pericyte dysfunction. Furthermore, in vivo experiments demonstrated that miR-205 agomir could ameliorate pulmonary hypertension. Our findings indicated that the downregulation of miR-205 expression mediates pericyte dysfunction through the activation of Ddx5. Therefore, targeting the miR-205/Ddx5/p-Gsk3ß/ß-catenin axis could be a promising therapeutic approach for IUGR-related pulmonary hypertension.


Asunto(s)
Proliferación Celular , ARN Helicasas DEAD-box , Epigénesis Genética , Retardo del Crecimiento Fetal , Glucógeno Sintasa Quinasa 3 beta , Hipertensión Pulmonar , MicroARNs , Pericitos , Ratas Sprague-Dawley , Animales , Femenino , Humanos , Masculino , Ratas , beta Catenina/metabolismo , beta Catenina/genética , Movimiento Celular/genética , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Retardo del Crecimiento Fetal/metabolismo , Retardo del Crecimiento Fetal/genética , Retardo del Crecimiento Fetal/patología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Hipertensión Pulmonar/genética , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , MicroARNs/genética , MicroARNs/metabolismo , Pericitos/metabolismo , Pericitos/patología
15.
Materials (Basel) ; 17(4)2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38399022

RESUMEN

In order to further explore the forming limits of thin-wall tube necking and thickening, and obtain sufficient thickness of the tube in the thickening area, local electric pulse-assisted forming experiments were carried out to study the effects of current intensity and feed speed on the necking and thickening forming of thin-wall tube. The experimental results show that with the increase in current intensity, the temperature in the forming area of the tube increases, and the forming load for necking and thickening decreases. However, with the increase in feed speed, the overall forming load for necking and thickening increases in general, and the smaller feed speed is more conducive to forming. Taking into account the forming efficiency and electrode loss, the corresponding forming process window is obtained for the manufacturing of good parts. That is, during the necking stage, the current intensity shall not be less than 300 A, and the feed speed shall not exceed 10 mm/min. During the thickening stage, the current intensity should not be less than 1400 A, and the feed speed should not exceed 1 mm/min. The target part is finally formed, with an average wall thickness of 5.984 mm in the thickening zone and a thickening rate of 303.2%.

16.
Nat Genet ; 56(3): 505-516, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38347217

RESUMEN

Dwarfing rootstocks have transformed the production of cultivated apples; however, the genetic basis of rootstock-induced dwarfing remains largely unclear. We have assembled chromosome-level, near-gapless and haplotype-resolved genomes for the popular dwarfing rootstock 'M9', the semi-vigorous rootstock 'MM106' and 'Fuji', one of the most commonly grown apple cultivars. The apple orthologue of auxin response factor 3 (MdARF3) is in the Dw1 region of 'M9', the major locus for rootstock-induced dwarfing. Comparing 'M9' and 'MM106' genomes revealed a 9,723-bp allele-specific long terminal repeat retrotransposon/gypsy insertion, DwTE, located upstream of MdARF3. DwTE is cosegregated with the dwarfing trait in two segregating populations, suggesting its prospective utility in future dwarfing rootstock breeding. In addition, our pipeline discovered mobile mRNAs that may contribute to the development of dwarfed scion architecture. Our research provides valuable genomic resources and applicable methodology, which have the potential to accelerate breeding dwarfing rootstocks for apple and other perennial woody fruit trees.


Asunto(s)
Malus , Malus/genética , Haplotipos/genética , Raíces de Plantas/genética , Fitomejoramiento , Fenotipo
17.
Nanoscale ; 16(9): 4620-4627, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38323483

RESUMEN

Construction of a built-in electric field has been identified as an attractive improvement strategy for photoelectrochemical (PEC) water splitting by facilitating the carrier extraction from the inside to the surface. However, the promotion effect of the electric field is still restrained by the confined built-in area. Herein, we construct a microscale built-in electric field via gradient oxygen doping. The octahedral configuration of the synthesized CdIn2S4 (CIS) provides a structural basis, which enables the subsequent oxygen doping to reach a depth of ∼100 nm. Accordingly, the oxygen-doped CIS (OCIS) photoanode exhibits a microscale built-in electric field with band bending. Excellent PEC catalytic activity with a photocurrent density of 3.69 mA cm-2 at 1.23 V vs. RHE is achieved by OCIS, which is 3.1 times higher than that of CIS. Combining the results of thorough characterization and theoretical calculations, accelerating migration and separation of charge carriers have been determined as the reasons for the improvement. Meanwhile, the recombination risk at the doping centers has also been reduced to the minimum via optimal experiments. This work provides a new-generation idea for constructing a built-in electric field from the view point of bulky configuration towards PEC water splitting.

18.
Biomicrofluidics ; 18(1): 011303, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38362304

RESUMEN

The robust identification and quantification of various biomarkers is of utmost significance in clinical diagnostics and precision medicine. Fluorescent immunoassays are widely used and considered as a gold standard for biomarker detection due to their high specificity and accuracy. However, current commercial immunoassay tests suffer from limited detection sensitivity and complicated, labor-intensive operation procedures, making them impractical for point-of-care diagnosis, particularly in resource-limited regions. Recently, microfluidic immunoassay devices integrated with plasmonic nanostructures have emerged as a powerful tool for sensitive detection of biomarkers, addressing specific issues, such as integration schemes, easy operation, multiplexed detection, and sensitivity enhancement. In this paper, we provide a discussion on the recent advances in the plasmonic nanostructures integrated with microfluidic devices for fluorescent immunoassays. We shed light on the nanofabrication strategies and various fluidic designs for rapid, sensitive, and highly efficient sensing of antigens. Finally, we share our perspectives on the potential directions of these integrated devices for practical applications.

19.
J Biomol Struct Dyn ; : 1-12, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38174403

RESUMEN

Staphylococcus aureus is one of the most frequently food-contaminated incidence of healthcare-associated Gram-positive bacteria. The antibacterial function and mechanism of phenolic compounds from dandelion are still unclear. Herein, this work aims to screen one of dandelion phenolic extracts with the strongest antibacterial function from its organ such as flower, stem, leaf and root, and to reveal its antibacterial mechanism. The results indicated dandelion flower phenolic extract (DFPE) containing the highest content of caffeic acid, followed by luteolin and luteolin-7-O-glucoside. They, especially caffeic acid and luteolin-7-O-glucoside, played a key role in making the bacterial cellular-membrane ruptured against the bacteria. The leakage of the intracellular substances (adenosine triphosphate and Na+-K+ ATPase) was further confirmed. Conventional hydrogen bond, pi-anion, pi-alkyl were involved in the interaction between caffeic acid or luteolin-7-O-glucoside and Na+-K+ ATPase. Additionally, the dynamic equilibrium of the liganded ATPase complex were achieved after 105 ns, and the lower values from the radius of gyration and solvent accessible surface area in the complex demonstrated the highly tight and compact structure of the liganded protein. The highest free binding energy (ΔGbind = -47.80 kJ/mol) between Na+-K+ ATPase and luteolin-7-O-glycloside was observed. Overall, DFPE can be used as an effective anti-bacterial agent due to the contribution of its bioactive ingredients such as caffeic acid and luteolin-7-O-glucoside for membrane-breaking.Communicated by Ramaswamy H. Sarma.

20.
Genes Genomics ; 46(2): 161-170, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38148455

RESUMEN

BACKGROUND: Myocardial ischemia/reperfusion (I/R) injury is closely related with cardiovascular diseases; however, the underlying pathogenic mechanisms remain not fully understood. This study sought to investigate the effect and mechanisms of PIM3 implicated in myocardial I/R injury using a rat model of myocardial I/R injury and a cell model of oxygen-glucose deprivation/reoxygenation (OGD/R) induction. METHODS: The morphology changes were detected by HE staining while cell viability was accessed by the CCK-8 method. The characteristics of ferroptosis were evaluated by ROS production, MDA content, SOD level, iron content, TfR1, FTH1, and GPX4 expression. RESULTS: Myocardial I/R operation increased myocardial tissue damage in rats, while OGD/R treatment reduced the viability of H9c2 cells. Both myocardial I/R operation and OGD/R stimulation increased ferroptosis, as demonstrated by elevated ROS, MDA, iron content, decreased SOD level, upregulation of TfR1, and downregulation of FTH1 and GPX4. Additionally, myocardial I/R modeling or OGD/R treatment enhanced the expression of PIM3. Silencing of PIM3 inhibited ferroptosis, which resulted in alleviated myocardial I/R-induced damage and improved H9c2 cell survival. CONCLUSIONS: Our findings highlight a vital role of PIM3 in myocardial I/R injury, indicating that PIM3-targeting ferroptosis may be a promising target for the development of novel therapies of myocardial I/R injury-associated diseases.


Asunto(s)
Enfermedad de la Arteria Coronaria , Ferroptosis , Daño por Reperfusión Miocárdica , Animales , Ratas , Ferroptosis/genética , Hierro , Daño por Reperfusión Miocárdica/genética , Especies Reactivas de Oxígeno , Superóxido Dismutasa
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