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1.
Angew Chem Int Ed Engl ; : e202320014, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598078

RESUMO

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.

2.
Dalton Trans ; 52(33): 11571-11580, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37547989

RESUMO

Bimetallic interstitial compounds with unique geometric properties have attracted increasing attention in energy-related fields and diverse chemical transformations. Current synthesis of these compounds generally involves at least one wet-chemistry step with the use of various solvents to prepare the bimetallic precursors, and no universal protocols for different compositions are yet available. Herein, a novel synthetic strategy toward a platform of nickel-based bimetallic interstitial compounds with the formula MNi3Cx, M = Zn, In, and Ga, was developed based on a straightforward solid-state transformation, i.e., simply annealing the hydroxides of the respective metals in the presence of different carbon precursors (cyanamide, dicyandiamide, melamine, and urea) in a hydrogen stream. The key process parameters influencing the compositions of the final products are studied and the formation mechanism is discussed based on advanced characterization techniques. Powder X-ray diffraction reveals MNi3Cx as a single phase and electron microscopy shows that the MNi3Cx particles are covered with N-doped carbon shells. Extrapolation to other bimetallic interstitial compounds failed when following the above protocol, and the successful examples are linked to the formation of the corresponding bimetallic alloys in the absence of carbon precursors. When evaluated for the selective hydrogenation of dimethyl oxalate, both InNi3C0.5 and ZnNi3C0.7 show comparable high activity. While ZnNi3C0.7 delivers the highest selectivity for methyl glycolate, tunable methyl glycolate and ethylene glycol are formed on InNi3C0.5. In general, this facile solvent-free strategy affords an interesting scaffold to fabricate more advanced multi-metallic interstitial compounds with broad applications.

3.
Org Biomol Chem ; 21(20): 4276-4281, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37144980

RESUMO

An easy to prepare nickel-coordinated mesoporous graphitic carbon nitride (Ni-mpg-CN) was introduced as a heterogeneous photocatalyst, which efficiently accelerated the photocatalytic C-N cross-coupling of (hetero)aryl bromides and aliphatic amines, delivering the desired monoaminated products in good yields. In addition, the concise synthesis of the pharmaceutical tetracaine was accomplished in the final stage, further highlighting the practical applicability.

4.
Front Genet ; 14: 1027690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36777735

RESUMO

Objective: To investigate the prognostic value of arachidonate lipoxygenases 5 (ALOX5) expression and methylation, and explore the immune functions of arachidonate lipoxygenases 5 expression in low-grade glioma (LGG). Materials and Methods: Using efficient bioinformatics approaches, the differential expression of arachidonate lipoxygenases 5 and the association of its expression with clinicopathological characteristics were evaluated. Then, we analyzed the prognostic significance of arachidonate lipoxygenases 5 expression and its methylation level followed by immune cell infiltration analysis. The functional enrichment analysis was conducted to determine the possible regulatory pathways of arachidonate lipoxygenases 5 in low-grade glioma. Finally, the drug sensitivity analysis was performed to explore the correlation between arachidonate lipoxygenases 5 expression and chemotherapeutic drugs. Results: arachidonate lipoxygenases 5 mRNA expression was increased in low-grade glioma and its expression had a notable relation with age and subtype (p < 0.05). The elevated mRNA level of arachidonate lipoxygenases 5 could independently predict the disease-specific survival (DSS), overall survival (OS), and progression-free interval (PFI) (p < 0.05). Besides, arachidonate lipoxygenases 5 expression was negatively correlated with its methylation level and the arachidonate lipoxygenases 5 hypomethylation led to a worse prognosis (p < 0.05). The arachidonate lipoxygenases 5 expression also showed a positive connection with immune cells, while low-grade glioma patients with higher immune cell infiltration had poor survival probability (p < 0.05). Further, arachidonate lipoxygenases 5 might be involved in immune- and inflammation-related pathways. Importantly, arachidonate lipoxygenases 5 expression was negatively related to drug sensitivity. Conclusion: arachidonate lipoxygenases 5 might be a promising biomarker, and it probably occupies a vital role in immune cell infiltration in low-grade glioma.

5.
Nanoscale ; 14(29): 10506-10513, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35830255

RESUMO

Tuning the coordination neighbors of the metal center is emerging as an elegant approach to manipulating the performance of supported single-atom catalysts in heterogeneous catalysis. Herein, atomically dispersed Pt species with different coordination neighbors hosted on nitrogen-doped carbon (NC) and graphitic carbon nitride (C3N4) are constructed through an impregnation-activation approach. Advanced characterization techniques including X-ray electron microscopy, X-ray absorption spectroscopy, and high angle annular dark-field scanning transmission electron microscopy reveal the different nature of active sites induced by the hosts: i.e., the Pt-Nx configuration in NC but both Pt-N and Pt-O coordinations in C3N4. H2-D2 exchange experiments and electron microscopy further evidence that Pt/NC exhibits a high propensity for H2 splitting and high thermal stability of the Pt species against agglomeration, whereas Pt/C3N4 cannot dissociate H2 and the Pt atoms easily aggregate in the reductive stream. Consequently, when applied in the selective hydrogenation of 1,3-butadiene, Pt/NC exhibits higher selectivity to butenes and excellent stability, but Pt/C3N4 behaves as a nanoparticle analogue favoring deep hydrogenation. The superior selectivity patterns of the single Pt atoms over Pt nanoparticles are rationalized by the inversed adsorption strength between the H2 and 1,3-butadiene molecules at different metal sites, which is substantiated by the kinetic studies.

6.
J Integr Neurosci ; 19(1): 101-109, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32259890

RESUMO

Medicinal plant breviscapine is shown to exhibit a protective role in tissue damage after cerebral hemorrhage. The effects of breviscapine on neurological deficit score, brain tissue water content, brain pathological tissue changes, blood-brain barrier bidirectional regulation, and inflammatory factors after cerebral hemorrhage in rats were observed. Western blot and real-time quantitative polymerase chain reaction were performed to explore how Periostin and nuclear factor kappa-B pathway-related factors protein expression contribute to the protective effects of breviscapine on brain injury. Breviscapine inhalation could reduce neurological deficit scores and brain tissue water content. Hematoxylin-eosin staining showed that breviscapine could improve the pathological changes of brain tissue and alleviate brain damage. Breviscapine reduced the abnormal increase of Evans blue content caused by a cerebral hemorrhage, and could significantly inhibit the levels of inflammatory factors interleukin-6 and tumor necrosis factor-α. Also, breviscapine significantly inhibited the expressions of Periostin and nuclear factor kappa-B pathway-related factors after cerebral hemorrhage, and alleviate brain damage by down-regulating Periostin expression and inhibiting nuclear factor kappa-ß signaling pathway.


Assuntos
Encéfalo/efeitos dos fármacos , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patologia , Flavonoides/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Moléculas de Adesão Celular/metabolismo , Hemorragia Cerebral/prevenção & controle , Mediadores da Inflamação/metabolismo , NF-kappa B/metabolismo , Plantas Medicinais , Ratos Sprague-Dawley , Transdução de Sinais
7.
ACS Nano ; 13(12): 14337-14347, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31769965

RESUMO

Despite the excellent catalytic properties of individual nanoparticles and atomic clusters, the current capabilities to assemble them into a complex system are insufficient for many practical applications. An objective of this work is to develop a fabrication technology that allows for the simultaneous control of the nanoparticle surface chemistry, elemental distribution, microscale geometry, and large-scale assembly. Using a cellulose structure derived from wood, we fabricate hierarchical porous cellulose scaffolds combining with cerium-doped TiO2. This hybrid material serves as the support for atomically dispersed Pt catalysts and is used to successfully decompose ethylene at 0 °C. The fabrication concept developed in this work would allow mitigating the conflict between the required large active surfaces and the difficulties in handling nanopowders in environmental catalysis, including food preservation and indoor air purification. We thus discover a promising route to manufacture multifunctional materials with complex structures by combining a controllable chemical synthesis with the nature-designed wood scaffold.

8.
Onco Targets Ther ; 12: 7297-7306, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686844

RESUMO

INTRODUCTION: Reactive oxygen species (ROS) are major contributors to cancer and involved in numerous tumor proliferation signaling pathways. Mitochondria are the major ROS-producing organelles, and ROS are produced from the synthesis of adenosine triphosphate and cell metabolism. METHODS: A novel mitochondria-targeted peptide, namely KRSH, was synthesized and characterized. KRSH consists of four amino acids; lysine and arginine contain positively charged groups that help KRSH target the mitochondria, while tyrosine and cysteine neutralize excessive endogenous ROS, thereby inhibiting tumorigenesis. RESULTS: The results indicated that KRSH is specifically inhibiting the growth of HeLa and MCF-7 cancer cell lines. However, MCF10A cells can resist the effects of KRSH even in a relative higher concentration. The dichloro-dihydro-fluorescein diacetate and MitoSOXTM Red assay suggested that KRSH drastically decreased the level of ROS in cancer cells. The mitochondrial depolarization assay indicated that treatment with KRSH at a dose of 50 nM may decrease the mitochondrial membrane potential leading to apoptosis of HeLa and MCF-7 cells. CONCLUSION: In other studies, investigating rat liver mitochondria, the uptake of KRSH may reach 80% compared with that for mitoquinone. Therefore, KRSH was designed as a superior peptide antioxidant and a mitochondria-targeting anticancer agent.

9.
Medicine (Baltimore) ; 98(17): e15443, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31027147

RESUMO

RATIONALE: Plasmacytoma as the 1st presentation of skull tumors is a rare disorder. When it is combined with brain trauma or dramatic changes in intracranial pressure, patients are more prone to misdiagnosis. PATIENT CONCERNS: A 67-year-old woman complaining of a headache presented with a history of head trauma for the past 1 hour. Emergency head computed tomography initially suggested an epidural hematoma. DIAGNOSIS: Emergency surgery was performed to remove the intracranial hematoma, but a tumor-like mass was found during surgery, and pathologic assessment confirmed plasmacytoma. Surgery was difficult because of bleeding. The tumor was radically removed. INTERVENTIONS AND OUTCOMES: The patient underwent whole-brain radiotherapy and chemotherapy. She died 40 months after the surgery. LESSONS: Epidural lesions found after a head injury may be assumed to be an epidural hematoma, leading to unnecessary surgery. Diseases such as hematomas, meningiomas, eosinophilic granulomas, bone metastases, and osteosarcomas must be considered.


Assuntos
Traumatismos Craniocerebrais/diagnóstico , Hematoma Epidural Craniano/diagnóstico , Plasmocitoma/diagnóstico , Neoplasias Cranianas/diagnóstico , Idoso , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/terapia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Hematoma Epidural Craniano/cirurgia , Humanos , Plasmocitoma/patologia , Plasmocitoma/terapia , Neoplasias Cranianas/patologia , Neoplasias Cranianas/terapia
10.
J Mol Neurosci ; 64(1): 129-139, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29243061

RESUMO

Curcumin, a polyphenolic compound extracted from Curcuma longa, has drawn attention for its effective bioactivities against ischemia-induced injury. This study aimed to evaluate the neuroprotective effect of curcumin and investigate the underlying mechanism that mediates autophagy and inflammation in an animal model of middle cerebral artery occlusion (MCAO) in rats. Curcumin was delivered to Sprague Dawley male rats at a dose of 200 mg/kg curcumin by intraperitoneal injection 30 min after ischemia-reperfusion (I/R). LY294002, a specific inhibitor of the PI3K/Akt/mTOR pathway, as well as anisomycin, an activator of TLR4/p38/MAPK, was administered by ventricle injection 30 min before MCAO. The same volume of saline was given as a control. Brain infarction and neurological function were determined 24 h post-MCAO. Immunoblotting and immunofluorescence were used to detect alterations in autophagy-relevant proteins Akt, p-Akt, mTOR, p-mTOR, LC3-II, and LC3-I, and inflammation-related proteins TLR4, p-38, p-p38, and IL-1 in the ipsilateral hemisphere. Cerebral I/R injury resulted in significant alterations of LC3-II/LC3-I, IL-1, TLR4, and p-p38. Curcumin in MCAO rats significantly improved brain damage and neurological function by upregulating p-Akt and p-mTOR and downregulating LC3-II/LC3-I, IL-1, TLR4, p-38, and p-p38. However, these protective effects against ischemia could be suppressed when LY294002 or anisomycin was included. Curcumin exerts neuroprotective effects by attenuating autophagic activities through mediating the PI3K/Akt/mTOR pathway, while also suppressing an inflammatory reaction by regulating the TLR4/p38/MAPK pathway. Furthermore, this study indicates that curcumin could be an effective therapy for patients afflicted with ischemia.


Assuntos
Anti-Inflamatórios/farmacologia , Autofagia/efeitos dos fármacos , Curcumina/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Curcumina/administração & dosagem , Curcumina/uso terapêutico , Interleucina-1/genética , Interleucina-1/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(11): 1312-1315, 2016 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30641622

RESUMO

Objective To observe the clinical efficacy of Wuling Powder (WP) combined ventricu- loperitoneal shunt surgery in patients with idiopathic normal-pressure hydrocephalus (INPH). Methods Totally 56 INPH patients were randomly assigned to the control group and the treatment group, 28 in each group. All patients received ventriculoperitoneal shunt surgery. Three days after surgery patients in the treatment group took WP, while those in the control group took placebo decoction (one dose per day, once in the morning and once in the evening, 7 days as one course, a total of 6 courses after surgery). Mini- Mental State Examination (MMSE) score, the steps to turn around 180°, and Evan's index were tested be- fore surgery and 3 months after surgery. Adverse reactions were recorded in the two groups. Clinical effica- cy was assessed after 3 months of surgery. Results At month 3 after surgery 21 patients (80. 8%) were cured and 3 patients (11. 5%) were improved in the treatment group, with statistical difference when com- pared with the control group [14 cured (51. 9%) and 11 improved (40. 7%) ; P <0. 05]. Compared with be- fore surgery in the same group, levels of MMSE score increased and the steps to turn around 1800 were obviously reduced in the two groups at month 3 after surgery (both P <0. 05). Compared with the control group at month 3 after surgery, levels of MMSE score increased and the steps to turn around 1800 were ob- viously reduced in the treatment group (both P <0. 05). Conclusion In treating INPH patierts, WP com- bined ventriculoperitoneal shunt surgery was superior to the effect of using ventriculoperitoneal- shunt sur- gery alone.


Assuntos
Medicamentos de Ervas Chinesas , Hidrocefalia de Pressão Normal , Derivação Ventriculoperitoneal , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Hidrocefalia de Pressão Normal/tratamento farmacológico , Hidrocefalia de Pressão Normal/cirurgia , Próteses e Implantes , Resultado do Tratamento
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