Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 14(1): 21212, 2024 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261579

RESUMO

The cost fluctuations associated with chemotherapy, radiotherapy, and immunotherapy, as primary modalities for treating malignant tumors, are closely related to medical decision-making and impose financial burdens on patients. In response to these challenges, China has implemented the Diagnosis-Related Group (DRG) payment system to standardize costs and control expenditures. This study collected hospitalization data from patients with malignant tumors who received chemotherapy, radiotherapy, and immunotherapy at Hospital H from 2018 to 2022. The dataset was segmented into two groups: the intervention group, treated with traditional Chinese medicine (TCM) alongside standard therapies, and the control group, treated with standard therapies alone. Changes and trends in hospitalization costs under the DRG policy were analyzed using propensity-score matching (PSM), standard deviation (SD), interquartile range (IQR), and concentration index (CI). Findings showed a decreasing trend in the standard deviation of hospitalization costs across all treatment modalities. Radiotherapy exhibited the most significant decrease, with costs reducing by 2547.37 CNY in the control group and 7387.35 CNY in the intervention group. Following the DRG implementation, the concentration indexes for chemotherapy and radiotherapy increased, while those for immunotherapy did not exhibit this pattern. Costs were more concentrated in patients who did not receive TCM treatment. In summary, DRG reform positively impacted the cost homogeneity of inpatient treatments for malignant tumors, particularly in the control group not receiving TCM treatment. The effects of DRG reform varied across different treatment modalities. Although short-term fluctuations in hospitalization costs may occur, initial evidence during the study period shows the positive impact of DRG reform on cost homogeneity.


Assuntos
Grupos Diagnósticos Relacionados , Neoplasias , Humanos , Neoplasias/terapia , Neoplasias/economia , Masculino , Feminino , Pessoa de Meia-Idade , Hospitalização/economia , China , Medicina Tradicional Chinesa/economia , Medicina Tradicional Chinesa/métodos , Imunoterapia/economia , Imunoterapia/métodos , Idoso , Custos de Cuidados de Saúde , Adulto
2.
Heliyon ; 10(18): e37735, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39328576

RESUMO

The primary aim of this study is to explore the role of AI in urban design and its potential to reduce pollution in Chinese cities. The study investigates how AI-driven urban planning tools can be applied to create more sustainable, efficient, and functional urban environments. PM2.5 and PM10 show high concentrations with peaks between 2014 and 2017, indicating simple pollution actions. Post-2017, there is a noticeable decline in pollution levels, possibly due to improved regulations or the global impact of the COVID-19 pandemic. Specific years, like 2016, show extreme spikes, possibly due to industrial activities or natural events. The overall trend suggests improved air quality and moderate to strong positive correlations exist between PM2.5 and PM10, NO2, SO2, and CO, indicating shared bases or co-occurrence. However, there is no significant correlation between PM2.5 and O3, suggesting different bases and behaviors. Bi-directional causality is observed between PM2.5 and PM10, PM2.5 and O3, PM2.5 and NO2, PM2.5 and SO2, and PM2.5 and CO. This mutual cause suggests interrelated impressive processes and shared bases. The results of the causality analysis suggest the existence of complex interactions, where high levels of pollution can predict changes in others. AI in urban design play vital role for identifying the most effective strategies for reducing pollution and helping to build more sustainable and functional urban environments in China.

3.
Sci Total Environ ; : 176603, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39349199

RESUMO

Studies have found that PM2.5 can damage the brain, accelerate cognitive impairment, and increase the risk of developing a variety of neurodegenerative diseases. However, the potential molecular mechanisms by which PM2.5 causes learning and memory problems are yet to be explored. In this study, we evaluated the neurotoxic effects in mice after 12 weeks of PM2.5 exposure, and found that this exposure resulted in learning and memory disorders, pathological brain damage, and M1 phenotype polarization on microglia, especially in the hippocampus. The severity of this damage increased with increasing PM2.5 concentration. Proteomic analysis, as well as validation results, suggested that PM2.5 exposure led to abnormal glucose metabolism in the mouse brain, which is mainly characterized by significant expression of hexokinase, phosphofructokinase, and lactate dehydrogenase. We therefore administered the glycolysis inhibitor 2-deoxy-d-glucose (2-DG) to the mice exposed to PM2.5, and showed that inhibition of glycolysis by 2-DG significantly alleviated PM2.5-induced hippocampal microglia M1 phenotype polarization, and reduced the release of inflammatory factors, improved synaptic structure and related protein expression, which alleviated the cognitive impairment induced by PM2.5 exposure. In summary, our study found that abnormal glucose metabolism-mediated inflammatory polarization of microglia played a role in learning and memory disorders in mice exposed to PM2.5. This study provides new insights into the neurotoxicity caused by PM2.5 exposure, and provides some theoretical references for the prevention and control of cognitive impairment induced by PM2.5 exposure.

4.
Nat Commun ; 15(1): 7826, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39244599

RESUMO

Enantioselective transformations of hydrocarbons to three-dimensional chiral molecules remain a significant challenge in synthetic chemistry. This study uses asymmetric paired oxidative and reductive catalysis to promote the enantioselective alkylarylation of olefins through the functionalization of C(sp3)-H bonds in alkanes. This asymmetric photoelectrocatalytic approach enables the facile construction of a wide range of enantioenriched α-aryl carbonyls with excellent enantioselectivity (up to 96% ee) from readily accessible starting materials. Notably, aryl bromides, aryl iodides, and even aryl chlorides were compatible with the developed catalytic system. Mechanistic studies reveal that alkanes and electrophiles are simultaneously activated on the electrodes.

5.
Front Public Health ; 12: 1420867, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39220456

RESUMO

Introduction: China is a large agricultural nation with the majority of the population residing in rural areas. The allocation of health resources in rural areas significantly affects the basic rights to life and health for rural residents. Despite the progress made by the Chinese government in improving rural healthcare, there is still room for improvement. This study aims to assess the spatial spillover effects of rural health resource allocation efficiency in China, particularly focusing on township health centers (THCs), and examine the factors influencing this efficiency to provide recommendations to optimize the allocation of health resources in rural China. Methods: This study analyzed health resource allocation efficiency in Chinese rural areas from 2012 to 2021 by using the super-efficiency SBM model and the global Malmquist model. Additionally, the spatial auto-correlation of THC health resource allocation efficiency was verified through Moran test, and three spatial econometric models were constructed to further analyze the factors influencing efficiency. Results: The key findings are: firstly, the average efficiency of health resource allocation in THCs was 0.676, suggesting a generally inefficient allocation of health resources over the decade. Secondly, the average Malmquist productivity index of THCs was 0.968, indicating a downward trend in efficiency with both non-scale and non-technical efficient features. Thirdly, Moran's Index analysis revealed that efficiency has a significant spatial auto-correlation and most provinces' values are located in the spatial agglomeration quadrant. Fourthly, the SDM model identified several factors that impact THC health resource allocation efficiency to varying degrees, including the efficiency of total health resource allocation, population density, PGDP, urban unemployment rate, per capita disposable income, per capita healthcare expenditure ratio, public health budget, and passenger traffic volume. Discussion: To enhance the efficiency of THC healthcare resource allocation in China, the government should not only manage the investment of health resources to align with the actual demand for health services but also make use of the spatial spillover effect of efficiency. This involves focusing on factors such as total healthcare resource allocation efficiency, population density, etc. to effectively enhance the efficiency of health resource allocation and ensure the health of rural residents.


Assuntos
Alocação de Recursos , China , Humanos , Serviços de Saúde Rural/estatística & dados numéricos , População Rural/estatística & dados numéricos , Alocação de Recursos para a Atenção à Saúde , Eficiência Organizacional/estatística & dados numéricos , Análise Espacial , Modelos Econométricos
6.
Chem Biol Drug Des ; 104(3): e14629, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39327238

RESUMO

Paeoniflorin (PF) is one of the active constituents of the traditional Chinese medicine Paeoniae Radix Rubra and has been actively explored in the pharmaceutical area due to its numerous pharmacological effects. However, severe difficulties such as limited bioavailability and low permeability limit its utilization. Therefore, this study developed and synthesized 25 derivatives of PF, characterized them by 1H NMR, 13C NMR, and HR-MS, and evaluated their antioxidant activity. Firstly, the antioxidant capacity of PF derivatives was investigated through DPPH radical scavenging experiment, ABTS radical scavenging experiment, reducing ability experiment, and O2 .- radical scavenging experiment. PC12 cells are routinely used to evaluate the antioxidant activity of medicines, therefore we utilize it to establish a cellular model of oxidative stress. Among all derivatives, compound 22 demonstrates high DPPH radical scavenging capacity, ABTS radical scavenging ability, reduction ability, and O2 .- radical scavenging ability. The results of cell tests reveal that compound 22 has a non-toxic effect on PC12 cells and a protective effect on H2O2-induced oxidative stress models. This might be due to the introduction of 2, 5-difluorobenzene sulfonate group in PF, which helps in scavenging free radicals under oxidative stress. Western blot and molecular docking indicated that compound 22 may exert antioxidant activity by activating Nrf2 protein expression. As noted in the study, compound 22 has the potential to be a novel antioxidant.


Assuntos
Antioxidantes , Glucosídeos , Simulação de Acoplamento Molecular , Monoterpenos , Glucosídeos/farmacologia , Glucosídeos/química , Glucosídeos/síntese química , Glucosídeos/metabolismo , Células PC12 , Monoterpenos/química , Monoterpenos/farmacologia , Monoterpenos/síntese química , Animais , Ratos , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peróxido de Hidrogênio , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/síntese química
7.
Artigo em Inglês | MEDLINE | ID: mdl-39190518

RESUMO

Self-supervised learning (SSL) is a challenging task in sleep stage classification (SSC) that is capable of mining valuable representations from unlabeled data. However, traditional SSL methods typically focus on single-view learning and do not fully exploit the interactions among information across multiple views. In this study, we focused on a multi-domain view of the same EEG signal and developed a self-supervised multi-view representation learning framework via time series and time-frequency contrasting (MV-TTFC). In the MV-TTFC framework, we built-in a cross-domain view contrastive learning prediction task to establish connections between the temporal view and time-frequency (TF) view, thereby enhancing the information exchange between multiple views. In addition, to improve the quality of the TF view inputs, we introduced an enhanced multisynchrosqueezing transform, which can create high energy concentration TF image views to compensate for the inaccurate representations in traditional TF processing techniques. Finally, integrating temporal, TF, and fusion space contrastive learning effectively captured the latent features in EEG signals. We evaluated MV-TTFC based on two real-world SSC datasets (SleepEDF-78 and SHHS) and compared it with baseline methods in downstream tasks. Our method exhibited state-of-the-art performance, achieving accuracies of 78.64% and 81.45% with SleepEDF-78 and SHHS, respectively, and macro F1-scores of 70.39% with SleepEDF-78 and 70.47% with SHHS.

8.
J Extracell Vesicles ; 13(7): e12470, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39001700

RESUMO

Extracellular vesicles (EVs) have emerged as a promising tool for clinical liquid biopsy. However, the identification of EVs derived from blood samples is hindered by the presence of abundant plasma proteins, which impairs the downstream biochemical analysis of EV-associated proteins and nucleic acids. Here, we employed optimized asymmetric flow field-flow fractionation (AF4) combined with density cushion ultracentrifugation (UC) to obtain high-purity and intact EVs with very low lipoprotein contamination from human plasma and serum. Further proteomic analysis revealed more than 1000 EV-associated proteins, a large proportion of which has not been previously reported. Specifically, we found that cell-line-derived EV markers are incompatible with the identification of plasma-EVs and proposed that the proteins MYCT1, TSPAN14, MPIG6B and MYADM, as well as the traditional EV markers CD63 and CD147, are plasma-EV markers. Benefiting from the high-purity of EVs, we conducted comprehensive miRNA profiling of plasma EVs and nanosized particles (NPs), as well as compared plasma- and serum-derived EVs, which provides a valuable resource for the EV research community. Overall, our findings provide a comprehensive assessment of human blood EVs as a basis for clinical biopsy applications.


Assuntos
Vesículas Extracelulares , Ultracentrifugação , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/química , Ultracentrifugação/métodos , Proteômica/métodos , MicroRNAs/sangue , Fracionamento por Campo e Fluxo/métodos , Biomarcadores/sangue , Biópsia Líquida/métodos , Centrifugação com Gradiente de Concentração/métodos
9.
Plast Reconstr Surg Glob Open ; 12(7): e6005, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39050033

RESUMO

Background: Due to their minimal trauma and relative safety, blood products are becoming increasingly popular in medical aesthetics. In recent years, research on the application of blood products has also been increased. This article will summarize the research progress of emerging blood products in plastic surgery in recent years. Methods: We searched the PubMed database for literature related to the application of blood preparation in plastic surgery over the past 5 years and summarized them. Results: Commonly used in plastic surgery are platelet-rich plasma, platelet-rich fibrin, concentrated growth factor, platelet-poor plasma, and mesenchymal stem cells derived from blood products. They can be used for wound repair and skin and autologous fat transplantation, and can be combined with laser therapy and facial rejuvenation. Conclusions: Understanding the application pathways of blood products in plastic surgery and their respective advantages and disadvantages can help us better choose and use them.

10.
Nat Commun ; 15(1): 5245, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898017

RESUMO

The simultaneous activation of reactants on the anode and cathode via paired electrocatalysis has not been extensively demonstrated. This report presents a paired oxidative and reductive catalysis based on earth-abundant iron/nickel cocatalyzed C-C functionalization of ubiquitous alcohols. A variety of alcohols (i.e., primary, secondary, tertiary, or unstrained cyclic alcohols) can be activated at very low oxidation potential of (~0.30 V vs. Ag/AgCl) via photoelectrocatalysis coupled with versatile electrophiles. This reactivity yields a wide range of structurally diverse molecules with broad functional group compatibility (more than 50 examples).

11.
Inorg Chem ; 63(21): 9983-9991, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38757519

RESUMO

Electrocatalytic CO2 reduction reaction (CO2RR) to ethanol has been widely researched for potential commercial application. However, it still faces limited selectivity at a large current density. Herein, Mo4+-doped CuS nanosheet-assembled hollow spheres are constructed to address this issue. Mo4+ ion doping modifies the local electronic environments and diversifies the binding sites of CuS, which increases the coverage of linear *COL and produces bridge *COB for subsequent *COL-*COH coupling toward ethanol production. The optimal Mo9.0%-CuS can electrocatalyze CO2 to ethanol with a faradaic efficiency of 67.5% and a partial current density of 186.5 mA cm-2 at -0.6 V in a flow cell. This work clarifies that doping high valence transition metal ions into Cu-based sulfides can regulate the coverage and configuration of related intermediates for ethanol production during the CO2RR in a flow cell.

12.
Forensic Sci Int Genet ; 71: 103056, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38678763

RESUMO

Domestic dogs are helpers in outdoor human work and companions for families; thus, individual canine identification and parentage testing are crucial in certain fields, including forensics and breeding programs. In this study, a six-dye fluorescent labeling multiplex amplification system containing 29 canine short tandem repeats (STRs) and the sex-determining marker DAmel was developed. The system was called the Tronfo Canine 30-plex STR Kit and was further validated according to the Scientific Working Group on DNA Analysis Methods and the Organization of Scientific Area Committees for Wildlife Forensics guidelines, including tests for PCR conditions, precision, species specificity, sensitivity, stability, repeatability and reproducibility, a population study, and a study of 16 paternity test cases. The results indicated that the novel canine STR assay was accurate, specific, reproducible, stable, and robust. Complete profiles were obtained with 31.25 pg of canine DNA. Additionally, 500 unrelated canine individuals were investigated using this novel system, and the combined power of discrimination and exclusion values were 0.999999999999999999 and 0.999996451039850, respectively. These results suggest that the Tronfo Canine 30-plex STR Kit is highly polymorphic, informative, and suitable for individual canine identification and parentage testing.


Assuntos
Repetições de Microssatélites , Animais , Cães/genética , Reprodutibilidade dos Testes , Especificidade da Espécie , Reação em Cadeia da Polimerase , Masculino , Impressões Digitais de DNA , Reação em Cadeia da Polimerase Multiplex , Feminino , Genética Forense/métodos
13.
Heliyon ; 10(7): e28608, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586331

RESUMO

Apoptosis is the primary cause of cell death in the differentiation of Adipose-derived stromal cells (ADSCs) into neurons. However, the relationship between endoplasmic reticulum stress (ERS) and death receptor-mediated apoptosis in ADSC-induced neuronal differentiation is not clear. ADSCs were isolated and induced to differentiate into neurons using ß-mercaptoethanol. The expression of neuron-specific enolase (NSE), GRP94, CHOP, Fas/FasL, TNFR1/TNF-α, DR5/TRAIL, Caspase8, and Caspase3 in ADSCs was examined using immunocytochemistry and Western blotting before induction, during pre-induction, and after induction. Transmission electron microscopy (TEM) was used to observe changes in the morphology of the endoplasmic reticulum (ER), and the MTT assay was employed to measure cell viability in the uninduced and induced groups. Additionally, the number of apoptotic cells during the induction process was measured using flow cytometry with Annexin V/PI. With increasing induction time, the positive expression rates of CHOP, Fas/FasL, Caspase8, Caspase-3, and NSE gradually increased, while the positive expression rate of GRP94 decreased. TNFR1/TNF-α and DR5/TRAIL peaked at 5 h post-induction and then decreased at 8 h. TEM revealed swelling and expansion of the ER, vacuolar changes, and degranulation in cells. The MTT assay showed a gradual decrease in the absorbance of surviving cells in all groups. Flow cytometry indicated an increasing rate of apoptosis in cells. Therefore, ERS in the normal culture and growth of ADSCs, manifesting as enhanced unfolded protein response (UPR), maintains the normal survival of ADSCs. However, in the process of ADSC-induced differentiation into neurons, ERS and death receptor-mediated apoptosis are significant causes of cell death.

14.
Forensic Sci Int ; 356: 111961, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377671

RESUMO

With the increasing importance of X-chromosome (Chr-X) genotyping in kinship identification, the exploitation of X chromosome genetic marker multiplex kits is increasing. The Human X-InDels amplification kit is a novel developed system which contained 38 X-chromosomal Insertion/deletion markers (X-InDels) and Amelogenin. Herein, we investigated the genetic diversity of the 38 X-InDels in the Tibetan ethnic minority (n = 792) from seven regions and evaluated the application potential of this novel panel. The rs16368 was the least variable locus, whereas the most polymorphic locus was the rs59605609 in Tibetan population. We confirmed three linkage groups with the haplotype diversities ranged from 0.5032 to 0.5976. The overall combined power of discrimination (PD) in males and females were 0.999999999582066 and 0.999999999999993, respectively. And the overall combined mean exclusion chance (MEC) values were not lower than 0.999125526990159. In addition, we explored the genetic relationships among the Tibetans in seven different regions via series of population comparison analyses, finding that the genetic relationship between the Ngari Tibetan and Chamdo Tibetan was the farthest, which was consistent with geographical distribution.


Assuntos
População do Leste Asiático , Etnicidade , Genética Populacional , Masculino , Feminino , Humanos , Frequência do Gene , Tibet/epidemiologia , Etnicidade/genética , Genética Forense , Grupos Minoritários , Cromossomo X , Estruturas Genéticas , China/epidemiologia
15.
Anal Biochem ; 688: 115476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38286351

RESUMO

The aim of this work was to develop a fast, simple, and reliable UPLC-MS3 method for the sensitive detection of acetochlor in biological samples. In MS3 mode, the ion transition m/z 270.1 â†’ 224.1→148.1 was chosen for quantification with butachlor as the internal standard. In the UPLC system, separation was performed on a UPLC column (2.1 × 50 mm ID, 1.7 µm) with 0.1 % FA in water and acetonitrile as mobile phases. After simple protein precipitation via acetonitrile, the method was well validated with good linearity (0.5-20 ng/mL, r > 0.995), accuracy (-3.70 %-2.98 %), and precision (<15 %). The selectivity and sensitivity were improved obviously in MS3 mode than that in MRM mode. The developed UPLC-MS3 method was successfully applied to the cellular pharmacokinetics study of acetochlor in MCF-7 cells.


Assuntos
Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem , Toluidinas , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Acetonitrilas
16.
J Sep Sci ; 47(2): e2300802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286730

RESUMO

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG-related Nano-drug delivery systems. A high through-put and selective ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method coupled with collision-induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study. The countless precursor ions of PEG1K are dissociated in the source to generate numerous product ions which have different numbers of subunits. The transition of [M+H]+ precursor ions → product ions at m/z 177.1 (four subunits)→89.1 (two subunits) was selected to determine PEG1K due to its high sensitivity. The UHPLC-MS/MS method coupled with CID in the source showed good linearity over the range of 0.1-10 µg/mL. Intra-day and inter-day accuracies and precisions of the assay were all within ± 12.39%. The assay was successfully applied to a cellular pharmacokinetic study of PEG1K in human breast cancer cells. The cytotoxicity of PEG1K polymers was also studied and the results indicated that the cytotoxicity of PEG1K was not significant in the range of 5-1200 µg/mL.


Assuntos
Polímeros , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Polímeros/toxicidade , Polímeros/análise , Polietilenoglicóis/química , Íons
17.
J Chromatogr Sci ; 62(3): 241-248, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36617938

RESUMO

ß-nicotinamide mononucleotide (NMN) has a good effect on delaying aging, repairing DNA and ameliorating metabolic disease. Biosynthesis with nicotinamide riboside kinase (NRK) takes a large part in NMN manufacture, but there is no available NMN quality standard and analytical method at present. In this study, we developed a specific high-performance liquid chromatography method for the assessment of NMN-related substances, including NMN and its potential impurities from NRK biological production and storage. Forced degradation study was performed under acid, base, oxidative, photolytic and thermal conditions. The separation of related substances was achieved on an Elite Hypersil ODS column using phosphate buffer-methanol gradient at a flow rate of 1.0 mL/min. The detection wavelength was maintained at 260 nm. The resolutions among all related substances were better than 1.5. Significant degradation was observed in basic and thermal conditions. All related substances showed good linearity with a coefficient of determination (R2) higher than 0.999. The accuracy values of all related substances were between 91.2% and 108.6%. Therefore, the validated analytical method is appropriate for inspecting the quality of NMN in its NRK biosynthetic manufacture and storage, thus further helping to unify NMN quality standards and facilitate related studies on NMN.


Assuntos
Mononucleotídeo de Nicotinamida , Mononucleotídeo de Nicotinamida/metabolismo , Cromatografia Líquida de Alta Pressão
18.
Adv Mater ; 36(13): e2311575, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38152896

RESUMO

Carbonaceous electrocatalysts offer advantages over metal-based counterparts, being cost-effective, sustainable, and electrochemically stable. Their high surface area increases reaction kinetics, making them valuable for environmental applications involving contaminant removal. However, their rational synthesis is challenging due to the applied high temperatures and activation steps, leading to disordered materials with limited control over doping. Here, a new synthetic pathway using carbon oxide precursors and tin chloride as a p-block metal salt melt is presented. As a result, highly porous oxygen-rich carbon sheets (with a surface area of 1600 m2 g-1) are obtained at relatively low temperatures (400 °C). Mechanistic studies reveal that Sn(II) triggers reductive deoxygenation and concomitant condensation/cross-linking, facilitated by the Sn(II) → Sn(IV) transition. Due to their significant surface area and oxygen doping, these materials demonstrate exceptional electrocatalytic activity in the nitrate-to-ammonia conversion, with an ammonia yield rate of 221 mmol g-1 h-1 and a Faradic efficiency of 93%. These results surpass those of other carbon-based electrocatalysts. In situ Raman studies reveal that the reaction occurs through electrochemical hydrogenation, where active hydrogen is provided by water reduction. This work contributes to the development of carbonaceous electrocatalysts with enhanced performance for sustainable environmental applications.

19.
Neuropsychiatr Dis Treat ; 19: 2657-2671, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38077236

RESUMO

Background: Post-stroke depression (PSD) is one of the most common complications of stroke. Electroacupuncture (EA) is an effective traditional Chinese medicine treatment for PSD, which is widely used in clinical settings. EA has a significant therapeutic effect against PSD, but the mechanism is still unclear. This study aimed to determine whether EA ameliorates depression-like behaviors in PSD rats by regulating the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)-mediated mitochondrial function. Methods: Middle cerebral artery occlusion (MCAO) and chronic unpredictable mild stress (CUMS) were used to develop a PSD rat model. To elucidate the role of AMPK in EA treatment, compound C, a selective inhibitor of AMPK, was injected into the lateral ventricle of rats before EA treatment. EA treatment was performed for 14 consecutive days for 30 min per day after PSD modeling. A modified Zea-Longa five-point scale scoring system was used to determine neurologic function in MCAO rats. Behavioral tests were conducted to evaluate depression-like phenotypes in rats. Depression-like behaviors were tested by sucrose preference test (SPT), novelty suppressed feeding test (NSFT), and open-field test (OFT). The structure and morphology of the prefrontal cortex were observed by histopathological hematoxylin-eosin (HE) and Nissl staining. The mitochondrial morphology and function were analyzed by colorimetry, chemiluminescence, Western blotting, and quantitative real-time polymerase chain reaction (qRT-PCR). Results: EA treatment successfully ameliorated depression-like behaviors, upregulated AMPK expression, and improved mitochondrial function. However, AMPK inhibition by Compound C exacerbated depression-like behaviors and aggravated neuronal and mitochondrial injury in PSD rats. Conclusion: EA treatment improved depression-like behaviors in PSD rats and promoted mitochondrial function by activating AMPK.

20.
J Am Chem Soc ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923566

RESUMO

It remains a challenge to design a catalyst with high selectivity at a large current density toward CO2 electrocatalytic reduction (CO2ER) to a single C1 liquid product of methanol. Here, we report the design of a catalyst by integrating MnO2 nanosheets with Pd nanoparticles to address this challenge, which can be implemented in membrane electrode assembly (MEA) electrolyzers for the conversion of CO2ER to methanol. Such a strategy modifies the electronic structure of the catalyst and provides additional active sites, favoring the formation of key reaction intermediates and their successive evolution into methanol. The optimal catalyst delivers a Faradaic efficiency of 77.6 ± 1.3% and a partial current density of 250.8 ± 4.3 mA cm-2 for methanol during CO2ER in an MEA electrolyzer by coupling anodic oxygen evolution reaction with a full-cell energy efficiency achieving 29.1 ± 1.2% at 3.2 V. This work opens a new avenue to the control of C1 intermediates for CO2ER to methanol with high selectivity and activity in an MEA electrolyzer.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA