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1.
Chempluschem ; : e202400240, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949230

RESUMEN

Lithium-ion batteries (LIBs) are widely used in electric vehicles, portable electronic devices, clean energy storage, and other fields due to their long service life, high energy density, and low self-discharge rate, which also puts forward higher requirements for the performance of lithium-ion batteries. As an anode for lithium-ion batteries, SiO materials have garnered significant attention from researchers due to its high specific capacity (2400 mAh·g-1), abundance of raw materials, and simple preparation. However, its large volume change (~ 200%) and poor electrical conductivity hinder its large-scale commercial application. Researchers employ various methods to reduce the volume change of SiO during lithium intercalation and improve its structural stability during cycling. This work mainly reviews the chemical structure and lithium storage mechanism of SiO, as well as the latest research progress on the preparation methods of SiO/C anode materials, focusing on summarizing the following preparation strategies: chemical vapor deposition, mechanical ball milling, spray drying, and in-situ reduction/oxidation methods. The obtained SiO-based anode materials' structural characteristics and electrochemical properties are compared and summarized. Finally, this review discusses the advantages and disadvantages of the current preparation methods, the future research directions, and the development prospects of SiO-based anode materials.

2.
Dev Neurosci ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955163

RESUMEN

INTRODUCTION: Neurosteroids have a variety of neurological functions, such as neurite growth, neuroprotection, myelination, and neurogenesis. P450scc, encoded by CYP11A1 gene, is the cholesterol side chain cleavage enzyme that catalyzes the first and rate limiting step in the steroidogenesis. In this study, we examine the dendritic morphology in developing hippocampal neurons of Cyp11a1 null mice at P15, a critical period for synapse formation and maturation. METHODS: Knockout mice were maintained until P15 with hormone administration. The Golgi-Cox method stained CA1 and CA3 pyramidal neurons in the hippocampus to reveal dendritic morphology. RESULTS: We demonstrated that Cyp11a1 null mice usually die within 7 days after birth and thus collected brain samples at postnatal day 5 (P5) for examination. There were significant shrinkage of dendrite size and diminishment of dendritic branching in CA1 and CA3 pyramidal neurons in the hippocampus of Cyp11a1 null mice, suggesting a developmental delay. We wonder if this delay may catch up later in life. Since the age of P15 is a critical period for synapse formation and maturation, the Cyp11a1 null mice were rescued by receiving hormone administration until P15 that the dendritic morphology in the developing hippocampal neurons could be examined. The results indicated that the total dendritic length, number of dendritic branches, as well as dendritic arborization in the CA1 and CA3 pyramidal neurons are significantly decreased in P15 knockout mice when compared to the wild type. The spine densities were also significantly decreased. In addition, the western blot analysis revealed decrease PSD-95 expression levels in the knockout mice compared to the wild type at P15. CONCLUSION: These results suggested that Cyp11a1 deficiency impairs the dendritic structures in the developing hippocampal pyramidal neurons.

3.
Med Sci Monit ; 30: e944285, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946121

RESUMEN

BACKGROUND Thrombosis poses a grave threat to patients undergoing kidney transplants, with a heightened risk of mortality. While previous studies have established a link between COVID-19 and thrombosis, the specific association between COVID-19 and thrombosis in this patient population remains unexplored. MATERIAL AND METHODS We conducted a retrospective analysis utilizing data from 394 individuals who underwent kidney transplantation within the period of September 1, 2015, to April 1, 2023. To evaluate overall survival, we employed Kaplan-Meier analysis and utilized a logistic regression model for risk analysis. Furthermore, we developed a prediction model and assessed its accuracy through calibration curves. RESULTS Out of the 394 patients included in our study, a total of 51 individuals experienced thrombosis, resulting in 2 deaths. Our analysis revealed that COVID-19 infection significantly increased the risk of thrombosis (odds ratio [OR] 8.60, 95% confidence interval 3.13-24.74, P<0.01). Additionally, the use of cyclosporine was found to elevate the risk of death (OR 20.86, 95% CI 7.93-59.24, P<0.01) according to multifactorial analysis. Logistic models were employed to screen variables, and predictive models were constructed based on the presence of COVID-19 infection and the usage of cyclosporine. A nomogram was developed, demonstrating promising accuracy in estimating the risk of thrombosis during internal validation, with a corrected C-index of 0.869. CONCLUSIONS Our study suggests that both COVID-19 infection and the use of cyclosporine can serve as reliable predictors of thrombosis risk in patients undergoing renal transplantation. Furthermore, we developed a mortality risk prediction model based on COVID-19 in assessing thrombosis.


Asunto(s)
COVID-19 , Trasplante de Riñón , Trombosis , Humanos , Trasplante de Riñón/efectos adversos , COVID-19/complicaciones , COVID-19/epidemiología , Trombosis/etiología , Trombosis/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Incidencia , Adulto , Pronóstico , Factores de Riesgo , Receptores de Trasplantes , SARS-CoV-2 , Modelos Logísticos , Anciano , Ciclosporina/uso terapéutico , Estimación de Kaplan-Meier
4.
Artículo en Inglés | MEDLINE | ID: mdl-38946401

RESUMEN

BACKGROUND AND AIM: Liver stiffness measurements (LSMs) are promising for monitoring disease progression or regression. We assessed the prognostic significance of dynamic changes in LSM over time on liver-related events (LREs) and death in patients with chronic hepatitis B (CHB) and compensated advanced chronic liver disease (cACLD). METHODS: This retrospective study included 1272 patients with CHB and cACLD who underwent at least two measurements, including LSM and fibrosis score based on four factors (FIB-4). ΔLSM was defined as [(follow-up LSM - baseline LSM)/baseline LSM × 100]. We recorded LREs and all-cause mortality during a median follow-up time of 46 months. Hazard ratios (HRs) and confidence intervals (CIs) for outcomes were calculated using Cox regression. RESULTS: Baseline FIB-4, baseline LSM, ΔFIB-4, ΔLSM, and ΔLSM/year were independently and simultaneously associated with LREs (adjusted HR, 1.04, 95% CI, 1.00-1.07; 1.02, 95% CI, 1.01-1.03; 1.06, 95% CI, 1.03-1.09; 1.96, 95% CI, 1.63-2.35, 1.02, 95% CI, 1.01-1.04, respectively). The baseline LSM combined with the ΔLSM achieved the highest Harrell's C (0.751), integrated AUC (0.776), and time-dependent AUC (0.737) for LREs. Using baseline LSM and ΔLSM, we proposed a risk stratification method to improve clinical applications. The risk proposed stratification based on LSM performed well in terms of prognosis: low risk (n = 390; reference), intermediate risk (n = 446; HR = 3.38), high risk (n = 272; HR = 5.64), and extremely high risk (n = 164; HR = 11.11). CONCLUSIONS: Baseline and repeated noninvasive tests measurement allow risk stratification of patients with CHB and cACLD. Combining baseline and dynamic changes in the LSM improves prognostic prediction.

5.
Cancer Lett ; : 217104, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38969163

RESUMEN

Results of measurable residual disease (MRD)-testing by next-generation sequencing (NGS) correlate with relapse risk in adults with B-cell acute lymphoblastic leukemia (ALL) receiving chemotherapy or an allotransplant from a human leukocyte antigen (HLA)-identical relative or HLA-matched unrelated donor. We studied cumulative incidence of relapse (CIR) and survival prediction accuracy using a NGS-based MRD-assay targeting immunoglobulin genes after 2 courses of consolidation chemotherapy cycles in 93 adults with B-cell ALL most receiving HLA-haplotype-matched related transplants. Prediction accuracy was compared with MRD-testing using multi-parameter flow cytometry (MPFC). NGS-based MRD-testing detected residual leukemia in 28 of 65 subjects with a negative MPFC-based MRD-test. In Cox regression multi-variable analyses subjects with a positive NGS-based MRD-test had a higher 3-year CIR (Hazard Ratio [HR] = 3.37; 95% Confidence Interval [CI], 1.34-8.5; P = 0.01) and worse survival (HR = 4.87 [1.53-15.53]; P = 0.007). Some data suggest a lower CIR and better survival in NGS-MRD-test-positive transplant recipients but allocation to transplant was not random. Our data indicate MRD-testing by NGS is more accurate compared with testing by MPFC in adults with B-cell ALL in predicting CIR and survival. (Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTROPC-14005546]).

6.
Sci Rep ; 14(1): 15092, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956160

RESUMEN

This study investigates the deformation and damage characteristics of the surrounding rock along the top return mining roadway of an isolated island working face at different stages and reveals its damage mechanism and evolution law. Utilizing a mine in Yangquan City, Shanxi Province, China, as the engineering background, this research employs FLAC 3D numerical simulation and on-site measurements. The findings suggest that the evolution of the plastic zone along the top roadway of the 15,106 island face is largely similar during both the excavation and mining periods. The plastic zones on either side of the roadway are expanding asymmetrically and gradually merging into the plastic zone of the coal pillar. In the destructive stage, the sub-gangs of the roadway are penetrated, indicating the progression into the plastic zone. The investigation points to extensive damage on the larger side of the roadway, the development of fissures, and the significant depth of damage as primary causes of roadway deformation. Moreover, the extent of the plastic zones on both sides of the roadway correlates positively with their relative distance. Continuous monitoring reveals an ongoing increase in roadway displacement, consistent with general observations in coal mining. The results provide valuable insights for optimizing support structures in similar mining environments.

7.
Angew Chem Int Ed Engl ; : e202410979, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967363

RESUMEN

Catalytic removal of alkynes is essential in industry for producing polymer-grade alkenes from steam cracking processes. Non-noble Ni-based catalysts hold promise as effective alternatives to industrial Pd-based catalysts but suffer from low activity. Here we report embedding of single-atom Pd onto the NiGa intermetallic surface with replacing Ga atoms via a well-defined synthesis strategy to design Pd1-NiGa catalyst for alkyne semi-hydrogenation. The fabricated Pd1Ni2Ga1 ensemble sites deliver remarkably higher specific mass activity under superb alkene selectivity of >96% than the state-of-the-art catalysts under industry-relevant conditions. Integrated experimental and computational studies reveal that the single-atom Pd located synergizes with the neighbouring Ni sites to facilitate the σ-adsorption of alkyne and dissociation of hydrogen while suppress the alkene adsorption. Such synergistic effects confer the single-atom Pd on the NiGa intermetallic with a Midas touch for alkyne semi-hydrogenation, providing an effective strategy for stimulating low active Ni-based catalysts for other selective hydrogenations in industry.

8.
Clin Transplant ; 38(7): e15396, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967600

RESUMEN

INTRODUCTION: Central nervous system leukemia (CNSL) remains a serious complication in patients with acute myeloid leukemia (AML) and an ambiguous prognostic factor for those receiving allo-geneic hematopoiesis stem cell transplantation (allo-HSCT). It is unknown whether using more sensitive tools, such as multiparameter flow cytometry (MFC), to detect blasts in the cerebrospinal fluid (CSF) would have an impact on outcome. METHODS: We retrospectively analyzed the clinical outcomes of 1472 AML patients with or without cytology or MFC positivity in the CSF before transplantation. Abnormal CSF (CSF+) was detected via conventional cytology and MFC in 44 patients at any time after diagnosis. A control group of 175 CSF-normal (CSF-) patients was generated via propensity score matching (PSM) analyses according to sex, age at transplant, and white blood cell count at diagnosis. RESULTS: Compared to those in the CSF-negative group, the conventional cytology positive and MFC+ groups had comparable 8-year nonrelapse mortality (NRM) (4%, 4%, and 6%, p = 0.82), higher cumulative incidence of relapse (CIR) (14%, 31%, and 32%, p = 0.007), lower leukemia-free survival (LFS) (79%, 63%, and 64%, p = 0.024), and overall survival (OS) (83%, 63%, and 68%, p = 0.021), with no significant differences between the conventional cytology positive and MFC+ groups. Furthermore, multivariate analysis confirmed that CSF involvement was an independent factor affecting OS and LFS. CONCLUSION: Our results indicate that pretransplant CSF abnormalities are adverse factors independently affecting OS and LFS after allotransplantation in AML patients.


Asunto(s)
Citometría de Flujo , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Trasplante Homólogo , Humanos , Femenino , Masculino , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/líquido cefalorraquídeo , Leucemia Mieloide Aguda/mortalidad , Estudios Retrospectivos , Adulto , Pronóstico , Persona de Mediana Edad , Estudios de Seguimiento , Adolescente , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Tasa de Supervivencia , Adulto Joven , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/líquido cefalorraquídeo , Enfermedad Injerto contra Huésped/diagnóstico , Enfermedad Injerto contra Huésped/mortalidad , Anciano , Niño , Citología
9.
BMC Psychiatry ; 24(1): 475, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937737

RESUMEN

BACKGROUND: This study aimed to explore discrepancies in adolescents with chronic illness and their parents' perceptions of family resilience, as well as the relationship between these differences and the psychological adjustment of adolescents with chronic illness. METHODS: A cross-sectional study was conducted. A total of 264 dyads of parents (77.7% mothers, mean age 41.60 years, SD = 6.17) and adolescents (48.5% girls, mean age 12.68 years, SD = 2.11) with chronic illness were recruited through convenience sampling from three children's hospitals in Wenzhou, Hangzhou, and Shanghai, China between June 2022 and May 2023. The Chinese version of the Family Resilience Scale and the Psychological Adjustment Scale, which are commonly used measures with good reliability and validity, were employed to assess family resilience and psychological adaption, respectively. The data were analyzed using polynomial regression and response surface analysis. RESULTS: Adolescents with chronic illness reported higher family resilience than their parents (t=-2.80, p < 0.05). The correlations between family resilience and adolescents' psychological adjustment reported by the adolescents (r = 0.45-0.48) were higher than parents (r = 0.18-0.23). In the line of congruence, there were positive linear (a1 = 1.09-1.60, p < 0.001) and curvilinear (a2=-1.38∼-0.72, p < 0.05) associations between convergent family resilience and adolescents' psychological adjustment. In the line of incongruence, when adolescents reported lower family resilience than parents, adolescents had a lower level of psychological adjustment (a3=-1.02∼-0.45, p < 0.05). Adolescents' sociability decreased when the perceived family resilience of parent-adolescent dyads converged (a4 = 1.36, p < 0.01). CONCLUSION: The findings highlighted the importance of considering the discrepancies and congruence of family resilience in the parent-child dyads when developing interventions to improve the psychological adjustment of adolescents with chronic illness. Interventions aimed at strengthening family communication to foster the convergence of perceptions of family resilience in parent-adolescent dyads were warranted.


Asunto(s)
Ajuste Emocional , Padres , Resiliencia Psicológica , Humanos , Femenino , Adolescente , Masculino , Enfermedad Crónica/psicología , Estudios Transversales , Padres/psicología , Adulto , Niño , China , Adaptación Psicológica , Familia/psicología , Persona de Mediana Edad
10.
Aerosp Med Hum Perform ; 95(7): 375-380, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38915163

RESUMEN

INTRODUCTION: Modular organization in brain regions often performs specific biological functions and is largely based on anatomically and/or functionally related brain areas. The current study aimed to explore changes in whole-brain modular organization affected by flight training.METHODS: The study included 25 male flight cadets and 24 male controls. The first assessment was performed in 2019, when the subjects were university freshmen. The second assessment was completed in 2022. High spatial resolution structural imaging (T1) and resting-state functional MRI data were collected. Then, 90 cerebral regions were organized into 6 brain modules. The intensity of intra- and intermodular communication was calculated.RESULTS: Mixed-effect regression model analysis identified significantly increased interconnections between the parietal and occipital modules in the cadet group, but significantly decreased interconnections in the control group. This change was largely attributed to flight training.DISCUSSION: Pilots need to control the aircraft (e.g., attitude, heading, etc.) using the stick and pedal in response to the current state of the aircraft displayed by the instrument panel; as such, flying requires a large amount of hand-eye coordination. Day-to-day flight training appeared to intensify the connection between the parietal and occipital modules among cadets.Chen X, Jiang H, Meng Y, Xu Z, Luo C. Increased functional connectivity between the parietal and occipital modules among flight cadets. Aerosp Med Hum Perform. 2024; 95(7):375-380.


Asunto(s)
Imagen por Resonancia Magnética , Lóbulo Occipital , Lóbulo Parietal , Pilotos , Humanos , Masculino , Lóbulo Occipital/fisiología , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Parietal/fisiología , Adulto Joven , Adulto , Estudios de Casos y Controles , Medicina Aeroespacial
11.
Phys Med Biol ; 69(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38843812

RESUMEN

Objective. In current clinical practice for quality assurance (QA), intensity modulated proton therapy (IMPT) fields are verified by measuring planar dose distributions at one or a few selected depths in a phantom. A QA device that measures full 3D dose distributions at high spatiotemporal resolution would be highly beneficial for existing as well as emerging proton therapy techniques such as FLASH radiotherapy. Our objective is to demonstrate feasibility of 3D dose measurement for IMPT fields using a dedicated multi-layer strip ionization chamber (MLSIC) device.Approach.Our developed MLSIC comprises a total of 66 layers of strip ion chamber (IC) plates arranged, alternatively, in thexandydirection. The first two layers each has 128 channels in 2 mm spacing, and the following 64 layers each has 32/33 IC strips in 8 mm spacing which are interconnected every eight channels. A total of 768-channel IC signals are integrated and sampled at a speed of 6 kfps. The MLSIC has a total of 19.2 cm water equivalent thickness and is capable of measurement over a 25 × 25 cm2field size. A reconstruction algorithm is developed to reconstruct 3D dose distribution for each spot at all depths by considering a double-Gaussian-Cauchy-Lorentz model. The 3D dose distribution of each beam is obtained by summing all spots. The performance of our MLSIC is evaluated for a clinical pencil beam scanning (PBS) plan.Main results.The dose distributions for each proton spot can be successfully reconstructed from the ionization current measurement of the strip ICs at different depths, which can be further summed up to a 3D dose distribution for the beam. 3D Gamma Index analysis indicates acceptable agreement between the measured and expected dose distributions from simulation, Zebra and MatriXX.Significance.The dedicated MLSIC is the first pseudo-3D QA device that can measure 3D dose distribution in PBS proton fields spot-by-spot.


Asunto(s)
Terapia de Protones , Radiometría , Radiometría/instrumentación , Terapia de Protones/instrumentación , Dosis de Radiación , Dosificación Radioterapéutica , Protones , Fantasmas de Imagen , Humanos , Radioterapia de Intensidad Modulada/instrumentación
12.
Dalton Trans ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916132

RESUMEN

We have studied whether dissociation of the S2B sulfide ligand from one of its two coordinating Fe ions may affect the later parts of the reaction mechanism of nitrogenase. Such dissociation has been shown to be favourable for the E2-E4 states in the reaction mechanism, but previous studies have assumed that S2B either remains bridging or has fully dissociated from the active-site FeMo cluster. We employ combined quantum mechanical and molecular mechanical (QM/MM) calculations with two density-functional theory methods, r2SCAN and TPSSh. To make dissociation of S2B possible, we have added a proton to this group throughout the reaction. We study the reaction starting from the E4 state with N2H2 bound to the cluster. Our results indicate that half-dissociation of S2B is unfavourable in most steps of the reaction mechanism. We observe favourable half-dissociation of S2B only when NH or NH2 is bound to the cluster, bridging Fe2 and Fe6. However, the former state is most likely not involved in the reaction mechanism and the latter state is only an intermittent intermediate of the E7 state. Therefore, half-dissociation of S2B seems to play only a minor role in the later parts of the reaction mechanism of nitrogenase. Our suggested mechanism with a protonated S2B is alternating (the two N atoms of the substrate is protonated in an alternating manner) and the substrate prefers to bind to Fe2, in contrast to the preferred binding to Fe6 observed when S2B is unprotonated and bridging Fe2 and Fe6.

13.
J Agric Food Chem ; 72(26): 14620-14629, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38885170

RESUMEN

Milk fat content is a critical indicator of milk quality. Exploring the key regulatory genes involved in milk fat synthesis is essential for enhancing milk fat content. STF-62247 (STF), a thiazolamide compound, has the potential to bind with ALG5 and upregulate lipid droplets in fat synthesis. However, the effect of STF on the process of milk fat synthesis and whether it acts through ALG5 remains unknown. In this study, the impact of ALG5 on milk fat synthesis and its underlying mechanism were investigated using bovine mammary epithelial cells (BMECs) and mouse models through real-time PCR, western blotting, Oil Red O staining, and triglyceride analysis. Experimental findings revealed a positive correlation between STF and ALG5 with the ability to synthesize milk fat. Silencing ALG5 led to decreased expression of FASN, SREBP1, and PPARγ in BMECs, as well as reduced phosphorylation levels in the PI3K/AKT/mTOR signaling pathway. Moreover, the phosphorylation levels of the PI3K/AKT/mTOR signaling pathway were restored when ALG5 silencing was followed by the addition of STF. These results suggest that STF regulates fatty acid synthesis in BMECs by affecting the PI3K/AKT/mTOR signaling pathway through ALG5. ALG5 is possibly a new factor in milk fat synthesis.


Asunto(s)
Células Epiteliales , Glándulas Mamarias Animales , Leche , Transducción de Señal , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Serina-Treonina Quinasas TOR , Animales , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/genética , Leche/química , Leche/metabolismo , Ratones , Bovinos , Femenino , Células Epiteliales/metabolismo , Glándulas Mamarias Animales/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Grasas/metabolismo , PPAR gamma/metabolismo , PPAR gamma/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Ácidos Grasos/metabolismo , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/metabolismo , Triglicéridos/metabolismo
14.
ACS Appl Mater Interfaces ; 16(26): 34089-34099, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38888573

RESUMEN

Slippery liquid-infused porous surfaces (SLIPSs) have great potential to replace traditional antifouling coatings due to their efficient, green, and broad-spectrum antifouling performance. However, the lubricant dissipation problem of SLIPS severely restricts its further development and application, and the robust SLIPS continues to be extremely challenging. Here, a composite phase-change lubricant layer consisting of paraffin, silicone oil, and MXene is designed to readily construct a stable and NIR-responsive self-healing phase-change solid slippery surface (PCSSS). Collective results showed that PCSSS could rapidly achieve phase-change transformation and complete self-healing under NIR irradiation and keep stable after high-speed water flushing, centrifugation, and ultrasonic treatment. The antifouling performance of PCSSS evaluated by protein, bacteria, and algae antiadhesion tests demonstrated the adhesion inhibition rate was as high as 99.99%. Moreover, the EIS and potentiodynamic polarization experiments indicated that PCSSS had stable and exceptional corrosion resistance (|Z|0.01Hz = 3.87 × 108 Ω·cm2) and could effectively inhibit microbiologically influenced corrosion. The 90 day actual marine test reveals that PCSSS has remarkable antifouling performance. Therefore, PCSSS presents a novel, facile, and effective strategy to construct a slippery surface with the prospect of facilitating its application in marine antifouling and corrosion protection.

15.
Org Biomol Chem ; 22(26): 5428-5453, 2024 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-38884683

RESUMEN

Here we report our design and synthesis of 28 new fluorine-containing compounds as potential F-18 radiotracers for CNS imaging of sphingosine-1-phosphate receptor 1 (S1PR1), and determination of their in vitro binding potency and selectivity toward S1PR1 over other S1PR subtypes. Nine potent and selective compounds, 7c&d, 9a&c, 12b, 15b, and 18a-c with IC50 values ranging from 0.6-12.3 nM for S1PR1 and weak binding toward S1PR2, 3, 4, and 5, were further 18F-radiolabeled to produce [18F]7c&d, [18F]9a&c, [18F]12b, [18F]15b, and [18F]18a-c. Multi-step F-18 radiochemistry procedures were investigated for radiosynthesis of [18F]7c&d and [18F]9a&c, and the presumed intermediates were synthesized and authenticated by analytic HPLC. We then performed nonhuman primate (NHP) PET brain imaging studies for eight radiotracers: [18F]7c&d, [18F]9a, [18F]12b, [18F]15b, and [18F]18a-c. Three radiotracers, [18F]7c, [18F]7d, and [18F]15b, had high NHP brain uptake with standardized uptake values (SUVs) at 2 h post-injection of 2.42, 2.84, and 2.00, respectively, and good brain retention. Our ex vivo biodistribution study in rats confirmed [18F]7d had a high brain uptake with no in vivo defluorination. Radiometabolic analysis of [18F]7c and [18F]7d in rat plasma and brain samples found that [18F]7c has a more favorable metabolic profile than [18F]7d. However, the trend of increased brain uptake precludes [18F]7c as a suitable PET radiotracer for imaging S1PR1 in the brain. Further structural optmization is warranted to identify a highly S1PR1-specific radiotracer with rapid brain uptake kinetics.


Asunto(s)
Diseño de Fármacos , Radioisótopos de Flúor , Receptores de Esfingosina-1-Fosfato , Animales , Radioisótopos de Flúor/química , Receptores de Esfingosina-1-Fosfato/metabolismo , Ratas , Tomografía de Emisión de Positrones/métodos , Radiofármacos/síntesis química , Radiofármacos/química , Radiofármacos/farmacocinética , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Receptores de Lisoesfingolípidos/metabolismo , Humanos , Distribución Tisular , Masculino , Macaca mulatta
16.
Nanomaterials (Basel) ; 14(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38869588

RESUMEN

Diabetes is a common disease that seriously endangers human health. Continuous glucose monitoring (CGM) is important for the prevention and treatment of diabetes. Glucose-sensing photonic nanochains (PNCs) have the advantages of naked-eye colorimetric readouts, short response time and noninvasive detection of diabetes, showing immense potential in CGM systems. However, the developed PNCs cannot disperse in physiological environment at the pH of 7.4 because of their poor hydrophilicity. In this study, we report a new kind of PNCs that can continuously and reversibly detect the concentration of glucose (Cg) in physiological environment at the pH of 7.4. Polyacrylic acid (PAA) added to the preparation of PNCs forms hydrogen bonds with polyvinylpyrrolidone (PVP) in Fe3O4@PVP colloidal nanoparticles and the hydrophilic monomer N-2-hydroxyethyl acrylamide (HEAAm), which increases the content of PHEAAm in the polymer shell of prepared PNCs. Moreover, 4-(2-acrylamidoethylcarbamoyl)-3-fluorophenylboronic acid (AFPBA), with a relatively low pKa value, is used as the glucose-sensing monomer to further improve the hydrophilicity and glucose-sensing performances of PNCs. The obtained Fe3O4@(PVP-PAA)@poly(AFPBA-co-HEAAm) PNCs disperse in artificial serum and change color from yellow-green to red when Cg increases from 3.9 mM to 11.4 mM, showing application potential for straightforward CGM.

17.
BMC Oral Health ; 24(1): 673, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851679

RESUMEN

BACKGROUND: Early childhood caries (ECC) remain a serious oral health problem on a global scale. Risk-based caries management (RBCM) implemented in some parts of the world has been effective in preventing ECC. However, there is a lack of prospective research on the application of RBCM among Chinese children, and little is known about its effectiveness. The purpose of this study was to evaluate the effectiveness of RBCM in preventing caries among children aged 3-5 years in Wanzhou District, Chongqing Municipality, China. METHODS: Three- to five-year-old children from four kindergartens in Wanzhou were randomly selected for baseline dental examination and caries risk assessment (CRA) and randomly assigned to the experimental group (EG) or the control group (CG) according to the kindergarten. The EG received caries prevention measures of different intensities based on the child's caries risk level. The CG received full-mouth fluoride twice a year according to standard prevention, regardless of their caries risk. One year later, another dental examination and CRA were conducted, to observe changes in the decayed, missing, and filled teeth (dmft) index and caries risk, and to analyze potential factors that may affect the incidence of new caries. RESULTS: Complete data were collected from 291 children (EG, N = 140, 84.8%; CG, N = 181, 83.4%). A total of 25.7% of the EG and 50.3% of the CG children developed new caries, with newly added dmft scores of 0.54 ± 1.12 and 1.32 ± 1.72, respectively (P < 0.05). Multivariate logistic regression indicated that children living in rural areas, assigned to the CG, and rated as high-risk at baseline were more likely to develop new caries (P < 0.05). The proportion of children with an increased caries risk in the EG was significantly lower than that in the CG (P < 0.05). CONCLUSIONS: RBCM effectively prevented new caries in 3- to 5-year-old Wanzhou children and reduced the proportion of children at increased risk of caries. It is an effective approach for preventing ECC. CLINICAL TRIAL REGISTRATION: This trial was registered in the Chinese Clinical Trials Register. The registration number was ChiCTR230067551 (11/01/2023).


Asunto(s)
Cariostáticos , Índice CPO , Caries Dental , Humanos , Caries Dental/prevención & control , Caries Dental/epidemiología , Preescolar , China/epidemiología , Método Simple Ciego , Masculino , Femenino , Cariostáticos/uso terapéutico , Medición de Riesgo , Estudios Prospectivos , Susceptibilidad a Caries Dentarias , Estudios de Seguimiento , Resultado del Tratamiento , Fluoruros/uso terapéutico , Pueblos del Este de Asia
18.
Carbohydr Polym ; 340: 122254, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38857998

RESUMEN

The inherent side effects of the physico-chemical properties of native starches often severely limit their use in food and non-food industries. Plasma is a non-thermal technology that allows rapid improvement of functional properties. This review provides a comprehensive summary of the sources and mechanisms of action of cold plasma and assesses its effects on starch morphology, crystal structure, molecular chain structure and physicochemical properties. The complex relationship between structure and function of plasma-treated starch is also explored. Potential applications of plasma-modified starch are also discussed in detail. The outcome of the modification process is influenced by factors such as starch type and concentration, plasma source, intensity and duration. The properties of starch can be effectively optimised using plasma technology. Plasma-based technologies therefore have the potential to modify starch to create a range of functionalities to meet the growing market demand for clean label ingredients.

19.
Adv Sci (Weinh) ; : e2305593, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38873820

RESUMEN

Centromere protein A (CENP-A), a histone H3 variant specific to centromeres, is crucial for kinetochore positioning and chromosome segregation. However, its regulatory mechanism in human cells remains incompletely understood. A structure-activity relationship (SAR) study of the cell-cycle-arresting indole terpenoid mimic JP18 leads to the discovery of two more potent analogs, (+)-6-Br-JP18 and (+)-6-Cl-JP18. Tubulin is identified as a potential cellular target of these halogenated analogs by using the drug affinity responsive target stability (DARTS) based method. X-ray crystallography analysis reveals that both molecules bind to the colchicine-binding site of ß-tubulin. Treatment of human cells with microtubule-targeting agents (MTAs), including these two compounds, results in CENP-A accumulation by destabilizing Cdh1, a co-activator of the anaphase-promoting complex/cyclosome (APC/C) E3 ubiquitin ligase. This study establishes a link between microtubule dynamics and CENP-A accumulation using small-molecule tools and highlights the role of Cdh1 in CENP-A proteolysis.

20.
Water Res ; 260: 121860, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38878319

RESUMEN

Dissolved inorganic carbon (DIC) provides a substrate for primary production in the lotic ecosystems, yet carbon's biogeochemical origination in the lotic food webs is still poorly constrained. Here, we assembled a global dataset of isotopic composition (i.e., 13C/12C or δ13C) of DIC and periphyton (algae being the primary producers) in river waters, and carried out a field study in two catchments respectively with carbonate and silicate dominated lithologies on the Tibetan Plateau. A two-endmember mixing model based on the datasets indicated that δ13C and concentrations of DIC in the river waters were largely determined by the catchment-scale chemical weathering of different lithologies. Meanwhile, a significant correlation was obtained between δ13C-DIC and δ13C-periphyton in the datasets, strongly implying that the origination of periphyton carbon was largely regulated by the catchment lithologies. The δ13C-periphyton compositions are also affected by isotopic fractionations during algal primary production, which, in turn, were closely related to the relationships between primary productivity and DIC availability in the rivers. The study advances our understanding of the origination and transfer of carbon biogeochemically bridging the geosphere and biosphere in the lotic ecosystems.

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