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1.
Heliyon ; 10(12): e32998, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38988566

RESUMEN

The development of novel drugs from basic science to clinical practice requires several years, much effort, and cost. Drug repurposing can promote the utilization of clinical drugs in cancer therapy. Recent studies have shown the potential effects of lomitapide on treating malignancies, which is currently used for the treatment of familial hypercholesterolemia. We systematically review possible functions and mechanisms of lomitapide as an anti-tumor compound, regarding the aspects of apoptosis, autophagy, and metabolism of tumor cells, to support repurposing lomitapide for the clinical treatment of tumors.

2.
Heliyon ; 10(11): e32630, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38961923

RESUMEN

Background and Purpose: Sex differences in acute ischemic stroke have been widely investigated, but the difference in acute ischemic stroke patients who received intravenous thrombolysis is not well understood. The current study was to investigate the issue based on a prospective cohort. Methods: From the Intravenous Thrombolysis Registry for Chinese Ischemic Stroke within 4.5h onset (INTRECIS) cohort, a total of 953 eligible patients with acute ischemic stroke were enrolled in final analysis. Based on 3-month modified Rankin scale score (mRS), patients were classified into good outcome group (mRS 0-1) and poor outcome group (mRS 2-6). Univariate and multivariate logistic regression analyses were used to identify predictive factors for clinical outcome in male or female patients. Results: Of the 953 patients treated with intravenous thrombolysis, 314 (32.9 %) were women. At day 90, we found no significant gender differences in good outcome (72.5 % vs 65.6 %, adjusted p = 0.414). We got the same results after propensity score matching (69.5 % vs 63.4 %, adjusted p = 0.637). Furthermore, we found that initial National Institute of Health Stroke Scale (NIHSS) score (odd ratio [OR] 0.877; 95 % CI 0.847-0.909, p < 0.001) and serum creatinine (OR 0.993; 95 % CI 0.986-1.000, p = 0 0.043) were found to be independent risk factors for poor outcome in male patients, while initial NIHSS score (OR 0.879; 95 % CI 0.839-0.920, p < 0.001), age (OR 0.970; 95 % CI 0.946-0.995, p = 0.017), systolic blood pressure (OR 0.984; 95 % CI 0.972-0.996, p = 0.007) and small artery occlusion (OR 2.718; 95 % CI 1.065-6.936, p = 0.036) in female patients. Conclusions: In this study, we found no gender difference in clinical outcome of thrombolysed stroke patients, but a difference in risk factors predicting outcome in male vs female patients was identified for the first time.

3.
Sci Rep ; 14(1): 15562, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38971863

RESUMEN

Systolic blood pressure variability (SBPV) is associated with outcome in acute ischemic stroke. Remote ischemic conditioning (RIC) has been demonstrated to be effective in stroke and may affect blood pressure. Relationship between SBPV and RIC treatment after stroke warrants investigation. A total of 1707 patients from per-protocol analysis set of RICAMIS study were included. The SBPV was calculated based on blood pressure measured at admission, Day 7, and Day 12. (I) To investigate the effect of SBPV on efficacy of RIC in stroke, patients were divided into High and Low categories in each SBPV parameter. Primary outcome was excellent functional outcome at 90 days. Compared with Control, efficacy of RIC in each category and interaction between categories were investigated. (II) To investigate the effect of RIC treatment on SBPV, SBPV parameters were compared between RIC and Control groups. Compared with Control, a higher likelihood of primary outcome in RIC was found in high category (max-min: adjusted risk difference [RD] = 7.2, 95% CI 1.2-13.1, P = 0.02; standard deviation: adjusted RD = 11.5, 95% CI 1.6-21.4, P = 0.02; coefficient of variation: adjusted RD = 11.2, 95% CI 1.4-21.0, P = 0.03). Significant interaction of RIC on outcomes were found between High and Low standard deviations (adjusted P < 0.05). No significant difference in SBPV parameters were found between treatment groups. This is the first report that Chinese patients with acute moderate ischemic stroke and presenting with higher SBPV, who were non-cardioemoblic stroke and not candidates for intravenous thrombolysis or endovascular therapy, would benefit more from RIC with respect to functional outcomes at 90 days, but 2-week RIC treatment has no effect on SBPV during hospital.


Asunto(s)
Presión Sanguínea , Precondicionamiento Isquémico , Accidente Cerebrovascular Isquémico , Humanos , Masculino , Femenino , Presión Sanguínea/fisiología , Anciano , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/fisiopatología , Persona de Mediana Edad , Precondicionamiento Isquémico/métodos , Resultado del Tratamiento , Sístole/fisiología
4.
CNS Neurosci Ther ; 30(7): e14868, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39014552

RESUMEN

BACKGROUND: Systolic blood pressure (SBP) was a predictor of early neurological deterioration (END) in stroke. We performed a secondary analysis of ARAMIS trial to investigate whether baseline SBP affects the effect of dual antiplatelet versus intravenous alteplase on END. METHODS: This post hoc analysis included patients in the as-treated analysis set. According to SBP at admission, patients were divided into SBP ≥140 mmHg and SBP <140 mmHg subgroups. In each subgroup, patients were further classified into dual antiplatelet and intravenous alteplase treatment groups based on study drug actually received. Primary outcome was END, defined as an increase of ≥2 in the NIHSS score from baseline within 24 h. We investigated effect of dual antiplatelet vs intravenous alteplase on END in SBP subgroups and their interaction effect with subgroups. RESULTS: A total of 723 patients from as-treated analysis set were included: 344 were assigned into dual antiplatelet group and 379 into intravenous alteplase group. For primary outcome, there was more treatment effect of dual antiplatelet in SBP ≥140 mmHg subgroup (adjusted RD, -5.2%; 95% CI, -8.2% to -2.3%; p < 0.001) and no effect in SBP <140 mmHg subgroup (adjusted RD, -0.1%; 95% CI, -8.0% to 7.7%; p = 0.97), but no significant interaction between subgroups was found (adjusted p = 0.20). CONCLUSIONS: Among patients with minor nondisabling acute ischemic stroke, dual antiplatelet may be better than alteplase with respect to preventing END within 24 h when baseline SBP ≥140 mmHg.


Asunto(s)
Presión Sanguínea , Fibrinolíticos , Inhibidores de Agregación Plaquetaria , Accidente Cerebrovascular , Activador de Tejido Plasminógeno , Humanos , Masculino , Femenino , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Anciano , Activador de Tejido Plasminógeno/uso terapéutico , Activador de Tejido Plasminógeno/administración & dosificación , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Fibrinolíticos/uso terapéutico , Fibrinolíticos/administración & dosificación , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/complicaciones , Anciano de 80 o más Años , Método Doble Ciego , Accidente Cerebrovascular Isquémico/tratamiento farmacológico
5.
Ann Clin Transl Neurol ; 11(7): 1703-1714, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38831636

RESUMEN

OBJECTIVE: We performed a post hoc exploratory analysis of Remote Ischemic Conditioning for Acute Moderate Ischemic Stroke (RICAMIS) to determine whether hypertension history and baseline systolic blood pressure (SBP) affect the efficacy of remote ischemic conditioning (RIC). METHODS: Based on the full analysis set of RICAMIS, patients were divided into hypertension versus non-hypertension group, or <140 mmHg versus ≥140 mmHg group. Each group was further subdivided into RIC and control subgroups. The primary outcome was modified Rankin Scale (mRS) 0-1 at 90 days. Efficacy of RIC was compared among patients with hypertension versus nonhypertension history and SBP of <140 mmHg versus ≥140 mmHg. Furthermore, the interaction effect of treatment with hypertension and SBP was assessed. RESULTS: Compared with control group, RIC produced a significantly higher proportion of patients with excellent functional outcome in the nonhypertension group (RIC vs. control: 65.7% vs. 57.0%, OR 1.45, 95% CI 1.06-1.98; p = 0.02), but no significant difference was observed in the hypertension group (RIC vs. control: 69.1% vs. 65.2%, p = 0.17). Similar results were observed in SBP ≥140 mmHg group (RIC vs. control: 68.0% vs. 61.2%, p = 0.009) and SBP <140 mmHg group (RIC vs. control: 65.6% vs. 64.7%, p = 0.77). No interaction effect of RIC on primary outcome was identified. INTERPRETATION: Hypertension and baseline SBP did not affect the neuroprotective effect of RIC, but they were associated with higher probability of excellent functional outcome in patients with acute moderate ischemic stroke who received RIC treatment.


Asunto(s)
Presión Sanguínea , Hipertensión , Precondicionamiento Isquémico , Accidente Cerebrovascular Isquémico , Humanos , Hipertensión/terapia , Hipertensión/fisiopatología , Masculino , Femenino , Anciano , Persona de Mediana Edad , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/fisiopatología , Presión Sanguínea/fisiología , Precondicionamiento Isquémico/métodos , Anciano de 80 o más Años
6.
Appl Environ Microbiol ; : e0054324, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38864627

RESUMEN

In the field of chiral amine synthesis, ω-amine transaminase (ω-ATA) is one of the most established enzymes capable of asymmetric amination under optimal conditions. However, the applicability of ω-ATA toward more non-natural complex molecules remains limited due to its low transamination activity, thermostability, and narrow substrate scope. Here, by employing a combined approach of computational virtual screening strategy and combinatorial active-site saturation test/iterative saturation mutagenesis strategy, we have constructed the best variant M14C3-V5 (M14C3-V62A-V116S-E117I-L118I-V147F) with improved ω-ATA from Aspergillus terreus (AtATA) activity and thermostability toward non-natural substrate 1-acetylnaphthalene, which is the ketone precursor for producing the intermediate (R)-(+)-1-(1-naphthyl)ethylamine [(R)-NEA] of cinacalcet hydrochloride, showing activity enhancement of up to 3.4-fold compared to parent enzyme M14C3 (AtATA-F115L-M150C-H210N-M280C-V149A-L182F-L187F). The computational tools YASARA, Discovery Studio, Amber, and FoldX were applied for predicting mutation hotspots based on substrate-enzyme binding free energies and to show the possible mechanism with features related to AtATA structure, catalytic activity, and stability in silico analyses. M14C3-V5 achieved 71.8% conversion toward 50 mM 1-acetylnaphthalene in a 50 mL preparative-scale reaction for preparing (R)-NEA. Moreover, M14C3-V5 expanded the substrate scope toward aromatic ketone compounds. The generated virtual screening strategy based on the changes in binding free energies has successfully predicted the AtATA activity toward 1-acetylnaphthalene and related substrates. Together with experimental data, these approaches can serve as a gateway to explore desirable performances, expand enzyme-substrate scope, and accelerate biocatalysis.IMPORTANCEChiral amine is a crucial compound with many valuable applications. Their asymmetric synthesis employing ω-amine transaminases (ω-ATAs) is considered an attractive method. However, most ω-ATAs exhibit low activity and stability toward various non-natural substrates, which limits their industrial application. In this work, protein engineering strategy and computer-aided design are performed to evolve the activity and stability of ω-ATA from Aspergillus terreus toward non-natural substrates. After five rounds of mutations, the best variant, M14C3-V5, is obtained, showing better catalytic efficiency toward 1-acetylnaphthalene and higher thermostability than the original enzyme, M14C3. The robust combinational variant acquired displayed significant application value for pushing the asymmetric synthesis of aromatic chiral amines to a higher level.

7.
8.
Mol Neurobiol ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850351

RESUMEN

Microglia are the most important immune cells in the central nervous system (CNS), which can defend against external pathogens and stimuli. Dysregulation of microglia releases excessive proinflammatory cytokines and leads to neuroinflammation, which is fundamental to the pathophysiology of multiple neurological diseases. However, the molecular mechanisms underlying the regulation of proinflammatory cytokines in microglia are still not well-understood. Here, we identified that inhibitor of DNA binding protein 2 (Id2) was a negative regulator of tumor necrosis factor-α (TNFα) in cultured microglia. Knockdown of Id2 significantly increased the expression of TNFα in microglia, while overexpression of Id2 inhibited TNFα expression. Furthermore, by interacting with the p65 subunit of nuclear factor kappa-B (NF-κB), Id2 suppressed the transcription activation of NF-κB and inhibited TNFα expression. Interestingly, in lipopolysaccharides (LPS)-treated microglia, Id2 increased and underwent a cytoplasmic relocation. Immunoprecipitation and immunostaining results showed that by binding to the LIM domain of Id2, a scaffold protein PDZ and LIM 5 (PDLIM5) involved in the Id2 cytoplasmic relocation, which inactivated Id2 and resulted in higher TNFα expression in LPS-treated microglia. Collectively, our data delineate a novel effect of Id2 on TNFα regulation in microglia, which may shed a light on the proinflammatory cytokines regulating in microglia associated neuroimmune disorders.

9.
Neurotherapeutics ; : e00382, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38852008

RESUMEN

BACKGROUND: The ARAIS trial didn't demonstrate argatroban significantly improve functional outcome at 90 days in acute ischemic stroke. We conducted post hoc analysis of ARAIS to investigate whether baseline neurological deficit was associated with outcomes. METHODS: Patients without endovascular therapy who met screening criteria as protocol and completed argatroban treatment were enrolled and classified into two subgroups according to NIHSS score at admission. Primary outcome was excellent functional outcome at 90 days, defined as mRS score of 0 to 1. Early neurological deterioration (END), defined as an increase of ≥4 in the NIHSS score from baseline within 48 hours, was investigated as secondary outcome. Compared with alteplase alone, we investigated treatment effect of argatroban plus alteplase on outcomes in subgroups and interaction with subgroups. RESULTS: A total of 675 patients from full analysis set were included: 390 were assigned into NIHSS score <10 subgroup and 285 into NIHSS score ≥10 subgroup. For primary outcome, there was similar treatment effect between argatroban plus alteplase and alteplase alone in NIHSS score ≥10 subgroup (adjusted RD, 5.8%; 95% CI, -6.0% to 17.5%; P = 0.33) and in NIHSS score <10 subgroup (adjusted RD, -1.4%; 95% CI, -9.9% to 7.1%; P = 0.75), and no significant interaction (P = 0.43). Occurrence of early neurological deterioration within 48 hours were significantly lower in NIHSS score ≥10 subgroup, compared with NIHSS score <10 subgroup (P = 0.006). CONCLUSION: Among patients with NIHSS score ≥10, argatroban plus alteplase could safely reduce END within 48 hours.

10.
Natl Sci Rev ; 11(7): nwae174, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38887544

RESUMEN

Chemically modified superatoms have emerged as promising candidates in the new periodic table, in which Au13 and its doped M n Au13- n have been widely studied. However, their important counterpart, Ag13 artificial element, has not yet been synthesized. In this work, we report the synthesis of Ag13 nanoclusters using strong chelating ability and rigid ligands, that fills the gaps in the icosahedral superatomic metal clusters. After further doping Ag13 template with different degrees of Au atoms, we gained insight into the evolution of their optical properties. Theoretical calculations show that the kernel metal doping can modulate the transition of the excited-state electronic structure, and the electron transfer process changes from local excitation (LE) to charge transfer (CT) to LE. This study not only enriches the families of artificial superatoms, but also contributes to the understanding of the electronic states of superatomic clusters.

11.
Front Genet ; 15: 1385293, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818040

RESUMEN

Background: Varicose veins (VV) are a common chronic venous disease that is influenced by multiple factors. It affects the quality of life of patients and imposes a huge economic burden on the healthcare system. This study aimed to use integrated analysis methods, including Mendelian randomization analysis, to identify potential pathogenic genes and drug targets for VV treatment. Methods: This study conducted Summary-data-based Mendelian Randomization (SMR) analysis and colocalization analysis on data collected from genome-wide association studies and cis-expression quantitative trait loci databases. Only genes with PP.H4 > 0.7 in colocalization were chosen from the significant SMR results. After the above analysis, we screened 12 genes and performed Mendelian Randomization (MR) analysis on them. After sensitivity analysis, we identified four genes with potential causal relationships with VV. Finally, we used transcriptome-wide association studies and The Drug-Gene Interaction Database data to identify and screen the remaining genes and identified four drug targets for the treatment of VV. Results: We identified four genes significantly associated with VV, namely, KRTAP5-AS1 [Odds ratio (OR) = 1.08, 95% Confidence interval (CI): 1.05-1.11, p = 1.42e-10] and PLEKHA5 (OR = 1.13, 95% CI: 1.06-1.20, p = 6.90e-5), CBWD1 (OR = 1.05, 95% CI: 1.01-1.11, p = 1.42e-2) and CRIM1 (OR = 0.87, 95% CI: 0.81-0.95, p = 3.67e-3). Increased expression of three genes, namely, KRTAP5-AS1, PLEKHA5, and CBWD1, was associated with increased risk of the disease, and increased expression of CRIM1 was associated with decreased risk of the disease. These four genes could be targeted for VV therapy. Conclusion: We identified four potential causal proteins for varicose veins with MR. A comprehensive analysis indicated that KRTAP5-AS1, PLEKHA5, CBWD1, and CRIM1 might be potential drug targets for varicose veins.

12.
J Hazard Mater ; 472: 134498, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38733782

RESUMEN

Advanced oxidation processes for the treatment of organic pollutants in wastewater suffer from difficulties in mineralization, potential risks of dissolved residues, and high oxidant consumption. In this study, radical-initiated polymerization is dominated in an UV/peroxydisulfate (PDS) process to eliminate organic pollutant of pharmaceutical metoprolol (MTP). Compared with an ideal degradation-based UV/PDS process, the present process can save four fifths of PDS consumption at the same dissolved organic carbon removal of 47.3%. Simultaneously, organic carbon can be recovered from aqueous solution by separating solid polymers at a ratio of 50% of the initial chemical oxygen demand. The chemical structure of products was analyzed to infer the transformation pathways of MTP. Unlike previous studies on simple organic pollutants that the polymerization can occur independently, the polymerization of MTP is dependent on the partial degradation of MTP, and the main monomer in polymerization is a dominant degradation product (4-(2-methoxyethyl)-phenol, denoted as DP151). The separated solid polymers are formed by repeated oxidation and coupling of DP151 or its derivatives through a series of intermediate oligomers. This proof-of-concept study demonstrates the advantage of polymerization-dominated mechanism on dealing with large organic molecules with complex structures, as well as the potential of UV/PDS process for simultaneous organic pollution reduction and organic carbon recovery from aqueous solution.

13.
BMC Pediatr ; 24(1): 307, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711038

RESUMEN

BACKGROUND: Anorectal malformation is a common congenital problem occurring in 1 in 5,000 births and has a spectrum of anatomical presentations, requiring individualized surgical treatments for normal growth. Delayed extubation or reintubation may result in a longer intensive care unit (ICU) stay and hospital stay, increased mortality, prolonged duration of mechanical ventilation, increased tracheostomy rate, and higher hospital costs. Extensive studies have focused on the role of risk factors in early extubation during major infant surgery such as Cardiac surgery, neurosurgery, and liver surgery. However, no study has mentioned the influencing factors of delayed extubation in neonates and infants undergoing angioplasty surgery. MATERIALS AND METHODS: We performed a retrospective study of neonates and infants who underwent anorectal malformation surgery between June 2018 and June 2022. The principal goal of this study was to observe the incidence of delayed extubation in pediatric anorectal malformation surgery. The secondary goals were to identify the factors associated with delayed extubation in these infants. RESULTS: We collected data describing 123 patients who had anorectal malformations from 2019 to 2022. It shows that 74(60.2%) in the normal intubation group and 49(39.8%) in the longer extubation. In the final model, anesthesia methods were independently associated with delayed extubation (P < 0.05). CONCLUSION: We found that the anesthesia method was independently associated with early extubation in neonates and infants who accepted pediatric anorectal malformation surgery.


Asunto(s)
Extubación Traqueal , Malformaciones Anorrectales , Humanos , Estudios Retrospectivos , Factores de Riesgo , Femenino , Masculino , Recién Nacido , Lactante , Factores de Tiempo , Malformaciones Anorrectales/cirugía , Perineo/cirugía
14.
High Alt Med Biol ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743636

RESUMEN

Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, and Jian Huang. Nitric oxide ameliorates the effects of hypoxia in mice by regulating oxygen transport by hemoglobin. High Alt Med Biol. 00:00-00, 2024.-Hypoxia is a common pathological and physiological phenomenon in ischemia, cancer, and strenuous exercise. Nitric oxide (NO) acts as an endothelium-derived relaxing factor in hypoxic vasodilation and serves as an allosteric regulator of hemoglobin (Hb). However, the ultimate effects of NO on the hematological system in vivo remain unknown, especially in extreme environmental hypoxia. Whether NO regulation of the structure of Hb improves oxygen transport remains unclear. Hence, we examined whether NO altered the oxygen affinity of Hb (Hb-O2 affinity) to protect extremely hypoxic mice. Mice were exposed to severe hypoxia with various concentrations of NO, and the survival time, exercise capacity, and other physical indexes were recorded. The survival time was prolonged in the 5 ppm NO (6.09 ± 1.29 minutes) and 10 ppm NO (6.39 ± 1.58 minutes) groups compared with the 0 ppm group (4.98 ± 1.23 minutes). Hypoxia of the brain was relieved, and the exercise exhaustion time was prolonged when mice inhaled 20 ppm NO (24.70 ± 6.87 minutes vs. 20.23 ± 6.51 minutes). In addition, the differences in arterial oxygen saturation (SO2%) (49.64 ± 7.29% vs. 42.90 ± 4.30%) and arteriovenous SO2% difference (25.14 ± 8.95% vs. 18.10 ± 6.90%) obviously increased. In ex vivo experiments, the oxygen equilibrium curve (OEC) left shifted as P50 decreased from 43.77 ± 2.49 mmHg (0 ppm NO) to 40.97 ± 1.40 mmHg (100 ppm NO) and 38.36 ± 2.78 mmHg (200 ppm NO). Furthermore, the Bohr effect of Hb was enhanced by the introduction of 200 ppm NO (-0.72 ± 0.062 vs.-0.65 ± 0.051), possibly allowing Hb to more easily offload oxygen in tissue at lower pH. The crystal structure reveals a greater distance between Asp94ß-His146ß in nitrosyl -Hb(NO-Hb), NO-HbßCSO93, and S-NitrosoHb(SNO-Hb) compared to tense Hb(T-Hb, 3.7 Å, 4.3 Å, and 5.8 Å respectively, versus 3.5 Å for T-Hb). Moreover, hydrogen bonds were less likely to form, representing a key limitation of relaxed Hb (R-Hb). Upon NO interaction with Hb, hydrogen bonds and salt bridges were less favored, facilitating relaxation. We speculated that NO ameliorated the effects of hypoxia in mice by promoting erythrocyte oxygen loading in the lung and offloading in tissues.

15.
Macromol Rapid Commun ; 45(13): e2400022, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38704741

RESUMEN

The preparation of self-healing polyurethane elastomers (PUEs) incorporating dynamic bonds is of considerable practical significance. However, developing a PUE with outstanding mechanical properties and high self-healing efficiency poses a significant challenge. Herein, this work has successfully developed a series of self-healing PUEs with various outstanding properties through rational molecular design. These PUEs incorporate m-xylylene diisocyanate and reversible dimethylglyoxime as hard segment, along with polytetramethylene ether glycol as soft segment. A significant amount of dynamic oxime-carbamate and hydrogen bonds are formed in hard segment. The microphase separated structure of the PUEs enables them to be colorless with a transparency of >90%. Owing to the chemical composition and multiple dynamic interactions, the PUEs are endowed with ultra-high tensile strength of 34.5 MPa, satisfactory toughness of 53.9 MJ m-3, and great elastic recovery both at low and high strains. The movement of polymer molecular chains and the dynamic reversible interactions render a self-healing efficiency of 101% at 70 °C. In addition, this self-healing polyurethane could still maintain high mechanical properties after recycling. This study provides a design strategy for the preparation of a comprehensive polyurethane with superior overall performance, which holds wide application prospects in the fields of flexible displays and solar cells.


Asunto(s)
Carbamatos , Elastómeros , Enlace de Hidrógeno , Oximas , Poliuretanos , Resistencia a la Tracción , Poliuretanos/química , Oximas/química , Elastómeros/química , Carbamatos/química , Estructura Molecular , Elasticidad
16.
Angew Chem Int Ed Engl ; : e202407887, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802322

RESUMEN

Circularly polarized light (CPL) detection is of great significance in various applications such as drug identification, sensing and imaging. Atomically precise chiral metal nanoclusters with intense circular dichroism (CD) signals are promising candidates for CPL detection, which can further facilitate device miniaturization and integration. Herein, we report the preparation of a pair of optically active chiral silver nanoclusters [Ag7(R/S-DMA)2(dpppy)3] (BF4)3 (R/S-Ag7) for direct CPL detection. The crystal structure and molecular formula of R/S-Ag7 clusters are confirmed by single-crystal X-ray diffraction and high-resolution mass spectrometry. R/S-Ag7 clusters exhibit strong CD spectra and CPL both in solution and solid states. When used as the photoactive materials in photodetectors, R/S-Ag7 enables effective discrimination between left-handed circularly polarized and right-handed circularly polarized light at 520 nm with short response time, high responsivity and considerable discrimination ratio. This study is the first report on using atomically precise chiral metal nanoclusters for CPL detection.

17.
J Pharm Biomed Anal ; 246: 116198, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38754154

RESUMEN

With the aging of the population, the prevalence of osteoporosis (OP) is rising rapidly, making it an important public health concern. Early screening and effective treatment of OP are the primary challenges facing the management of OP today. Quanduzhong capsule (QDZ) is a single preparation composed of Eucommia ulmoides Oliv., which is included in the Pharmacopoeia of the People's Republic of China. It is used to treat OP in clinical practice, but its mechanisms are unclear. This study involved 30 patients with OP, 30 healthy controls (HC), and 28 OP patients treated with QDZ to identify potential biomarkers for the early diagnosis of OP and to investigate the potential mechanism of QDZ in treating OP. The serum samples were analyzed using targeted amino acid metabolomics. Significant differences in amino acid metabolism were identified between the OP cohort and the HC group, as well as between OP patients before and after QDZ treatment. Compared with HC, the serum levels of 14 amino acids in OP patients changed significantly. Kynurenine, arginine, citrulline, methionine, and their combinations are expected to be potential biomarkers for OP diagnosis. Notably, QDZ reversed the changes in levels of 10 amino acids in the serum of OP patients and significantly impacted numerous metabolic pathways during the treatment of OP. This study focuses on screening potential biomarkers for the early detection of OP, which offers a new insight into the mechanism study of QDZ in treating OP.


Asunto(s)
Aminoácidos , Biomarcadores , Medicamentos Herbarios Chinos , Metabolómica , Osteoporosis , Humanos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Biomarcadores/sangre , Metabolómica/métodos , Osteoporosis/sangre , Osteoporosis/tratamiento farmacológico , Femenino , Persona de Mediana Edad , Masculino , Aminoácidos/sangre , Anciano , Cápsulas , Eucommiaceae , Estudios de Casos y Controles , Adulto
18.
ACS Nano ; 18(22): 14583-14594, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38722840

RESUMEN

Direct photosynthesis of hydrogen peroxide (H2O2) from water and oxygen represents an intriguing alternative to the current indirect process involving the reduction and oxidation of quinones. However, limited light utilization and sluggish charge transfer largely impede overall photocatalytic efficiency. Herein, we present a heavily doped carbon nitride (CNKLi) nanocrystal for efficient and selective photoproduction of H2O2 via a two-electron oxygen reduction reaction (ORR) pathway. CNKLi induces metal-to-ligand charge transfer (MLCT) and electron trapping, which broadens the light absorption to the visible-near-infrared (vis-NIR) spectrum and prolongs the photoelectron lifetime to the microsecond time scale with an exceptional charge diffusion length of ∼1200 nm. Near-unit photoutilization with an apparent quantum yield (AQY) of 100% for H2O2 generation is achieved below 420 nm. Impressively, CNKLi exhibits an appreciable AQY of 16% at 700 nm, which reaches the absorption capacity (∼16%), thus suggesting a near-unit photon utilization <700 nm. In situ characterization and theoretical calculations reveal the facilitated charge transfer from K+ to the heptazine ring skeleton. These findings provide an approach to improve the photosynthetic efficiency of direct H2O2 preparation in the vis-NIR region and expand applications for driving kinetically slow and technologically desirable oxidations or high-value chemical generation.

19.
J Am Chem Soc ; 146(22): 15640-15647, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38771765

RESUMEN

Single-atom catalysts (SACs) have been widely investigated and have emerged as a transformative approach in electrocatalysis. Despite their clear structure, the origin of their exceptional activity remains elusive. Herein, we elucidate a common phenomenon of the hybridization state transition of metal centers, which is responsible for the activity origin across various SACs for different reactions. Focusing on N-doped carbon-supported Ni SAC (NiN4 SAC) for CO2 reduction reaction (CO2RR), our comprehensive computations successfully clarify the hybridization state transition under working conditions and its relation with the activity. This transition, triggered by the reaction intermediates and applied potential, converts the Ni center from the inert dsp2 hybridization state to the active d2sp3 hybridization state. Importantly, the calculated activity and selectivity of the CO2RR over the d2sp3-hybridized Ni center are consistent with the experimental results, offering strong support for the proposed hypothesis. This work suggests a universal principle of electronic structure evolution in SACs that could revolutionize catalyst design, which also introduces a new paradigm for manipulating electronic states to enhance catalytic performance, with implications for various reactions and catalyst platforms.

20.
Plant Dis ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587799

RESUMEN

Salvia splendens is a popular ornamental plant in China with extensive potentials, including value in traditional Chinese medicine and in environmental restoration function (Li et al. 2008). In September 2019, leaf blight disease was observed on road side plants of S. splendens in Bayi park, Nanchang city, Jiangxi province, China. The typical symptoms appeared as irregular necrotic spots or leaf blight, accompanied by extensive scorch necrosis or ultimately defoliation. Small segments cut from diseased leaves were surface sterilized in a 2% sodium hypochlorite solution for 2 min and rinsed three times with sterile distilled water. Then, the samples were placed on potato dextrose agar (PDA) plates incubated at 25°C in darkness. Pure cultures were obtained by the hyphal tip method. Morphologically, all 11 colonies were identical to each other on PDA. Two strains, YZU 191468 and YZU 191481, were selected for further study and deposited in the Fungal Herbarium of Yangtze University (YZU), Jingzhou, Hubei, China. The 7-day-old colonies were circular, 53 to 56 mm in diameter, and consisted of white mycelium with a buff margin, and were cinnamon colored in the center of the reverse side. To examine conidial morphology, the mycelium was transferred onto potato carrot agar (PCA) and incubated at 23°C with a period of 8 h light/16 h dark for 7 days. Conidia were normally solitary or two in a chain, ellipsoid or long ellipsoid, beakless, 10 to 23×30 to 60 µm in size (n=50). Based on morphology, the isolates were consistent with Stemphylium lycopersici (Yamamoto 1960). To confirm the identification, genomic DNA was extracted from both isolates and used to amplify the internal transcribed spacer rDNA region (ITS), glyceraldehydes-3-phosphate dehydrogenase (GAPDH) and calmodulin (CAL) genes with primer pairs ITS5/ITS4, gpd1/gpd2, and CALDF1/CALDR2, respectively (Woudenberg et al. 2017). Sequences were deposited in GenBank with accession numbers OP564983 and OP564984 (ITS), OP892529 and OP892530 (GAPDH), OP584970 and OP584971 (CAL). A neighbor-joining tree was constructed with Mega 7.0 based on the combined dataset with 1,000 bootstrap replicates. The resulting phylogenetic tree showed that the strains from S. splendens clustered with S. lycopersici (CBS 122639 and CBS 124980) supported with 100% bootstrap values. The molecular analyses confirmed that the species causing leaf blight symptoms was S. lycopersici. To test pathogenicity, healthy leaves of S. splendens were surface sterilized and inoculated by mycelium blocks (6 mm in diameter) and spore suspension (1×106 spore/mL) of representative strains YZU 191468 and YZU 191481, respectively. Controls were inoculated with blocks of PDA and sterile water. Each strain was inoculated on three leaves of a plant. One clean plant was used as control. The test was replicated three times. After inoculation, the plants were covered with plastic bags and incubated in a greenhouse (25℃, 80 % relative humidity, 8 h light/16 h dark). After 5 days, the inoculated leaves exhibited dark brown spots with white mycelium, followed by withering of necrotic tissues. There were no symptoms observed on the controls. The fungal isolates inoculated leaves had the same morphological characteristics as the strains used for inoculation. S. lycopersici has been found on eggplant and Zinnia elegans in China (He et al. 2019; Yang et al. 2017). To the best of our knowledge, this is the first report of S. lycopersici causing leaf blight on S. splendens in China. This finding offers a new reference for the management and control of S. splendens leaf diseases in China.

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