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1.
Cell ; 152(5): 969-83, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23452847

RESUMO

Embedded in the nuclear envelope, nuclear pore complexes (NPCs) not only regulate nuclear transport but also interface with transcriptionally active euchromatin, largely silenced heterochromatin, as well as the boundaries between these regions. It is unclear what functional role NPCs play in establishing or maintaining these distinct chromatin domains. We report that the yeast NPC protein Nup170p interacts with regions of the genome that contain ribosomal protein and subtelomeric genes, where it functions in nucleosome positioning and as a repressor of transcription. We show that the role of Nup170p in subtelomeric gene silencing is linked to its association with the RSC chromatin-remodeling complex and the silencing factor Sir4p, and that the binding of Nup170p and Sir4p to subtelomeric chromatin is cooperative and necessary for the association of telomeres with the nuclear envelope. Our results establish the NPC as an active participant in silencing and the formation of peripheral heterochromatin.


Assuntos
Inativação Gênica , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Cromatina/química , Cromatina/metabolismo , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Nucleossomos/metabolismo , Proteínas Ribossômicas/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Telômero/metabolismo , Fatores de Transcrição/metabolismo
2.
J Am Chem Soc ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592685

RESUMO

The determination of catalytically active sites is crucial for understanding the catalytic mechanism and providing guidelines for the design of more efficient catalysts. However, the complex structure of supported metal nanocatalysts (e.g., support, metal surface, and metal-support interface) still presents a big challenge. In particular, many studies have demonstrated that metal-support interfaces could also act as the primary active sites in catalytic reactions, which is well elucidated in oxide-supported metal nanocatalysts but is rarely reported in carbon-supported metal nanocatalysts. Here, we fill the above gap and demonstrate that metal-sulfur interfaces in sulfur-doped carbon-supported metal nanocatalysts are the primary active sites for several catalytic hydrogenation reactions. A series of metal nanocatalysts with similar sizes but different amounts of metal-sulfur interfaces were first constructed and characterized. Taking Ir for quinoline hydrogenation as an example, it was found that their catalytic activities were proportional to the amount of the Ir-S interface. Further experiments and density functional theory (DFT) calculations suggested that the adsorption and activation of quinoline occurred on the Ir atoms at the Ir-S interface. Similar phenomena were found in p-chloronitrobenzene hydrogenation over the Pt-S interface and benzoic acid hydrogenation over the Ru-S interface. All of these findings verify the predominant activity of metal-sulfur interfaces for catalytic hydrogenation reactions and contribute to the comprehensive understanding of metal-support interfaces in supported nanocatalysts.

3.
Anal Chem ; 96(5): 2244-2252, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38253329

RESUMO

Tumor-derived extracellular vesicle (T-EV) microRNAs have been investigated as promising biomarkers in clinical diagnosis as well as disease progression monitoring. However, the expression profiles of microRNA in different tissues vary widely, the precise monitoring of microRNA levels in EVs originating from diseased tissues is susceptible to background interference, thus remains a challenge. Conventional assays require extensive processing, such as EV isolation and even sample lysis, which is both slow and laborious, and the cumbersome pretreatment could spoil the downstream analysis. To address this issue, we developed a generalizable strategy for T-EVs-selective activation and therefore specific amplified microRNA imaging. The conditional signal amplification is established by integrating a traditional DNA walker system with endogenously activated motif to achieve sensitized microRNA imaging in T-EVs. The preorganized endogenous activation with additional sensing criteria narrowed the scope against the complex specimens, and the amplified sensing with reduced off-target signals was supposed to be sensitive to monitor the tiny changes of microRNA expression during the disease course, which holds great potential for accurate diagnosis and prognosis.


Assuntos
Vesículas Extracelulares , MicroRNAs , MicroRNAs/análise , DNA/metabolismo , Vesículas Extracelulares/química , Prognóstico , Biomarcadores Tumorais/metabolismo
4.
J Chem Inf Model ; 64(7): 2817-2828, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37167092

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease with a broad spectrum of histologic manifestations. The rapidly growing prevalence and the complex pathologic mechanisms of NAFLD pose great challenges for treatment development. Despite tremendous efforts devoted to drug development, there are no FDA-approved medicines yet. Here, we present NAFLDkb, a specialized knowledge base and platform for computer-aided drug design against NAFLD. With multiperspective information curated from diverse source materials and public databases, NAFLDkb presents the associations of drug-related entities as individual knowledge graphs. Practical drug discovery tools that facilitate the utilization and expansion of NAFLDkb have also been implemented in the web interface, including chemical structure search, drug-likeness screening, knowledge-based repositioning, and research article annotation. Moreover, case studies of a knowledge graph repositioning model and a generative neural network model are presented herein, where three repositioning drug candidates and 137 novel lead-like compounds were newly established as NAFLD pharmacotherapy options reusing data records and machine learning tools in NAFLDkb, suggesting its clinical reliability and great potential in identifying novel drug-disease associations of NAFLD and generating new insights to accelerate NAFLD drug development. NAFLDkb is freely accessible at https://www.biosino.org/nafldkb and will be updated periodically with the latest findings.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Reprodutibilidade dos Testes , Desenvolvimento de Medicamentos
5.
J Fluoresc ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478263

RESUMO

As a non-invasive body fluid, urine pH is one of the important biomarkers for diseases such as the kidneys. Therefore, rapid and accurate detection of urine pH is of great clinical significance. A novel fluorescent probe (SPPH-Cl) was developed based on Brooker's merocyanine skeleton for pH detection. The pKa of SPPH-Cl was adjusted to 6.55 using a phenolic hydroxyl ortho substitution strategy, therefore, the fluorescence response range of SPPH-Cl to pH covers the urine physiological pH range (4.6-8.0). SPPH-Cl has excellent water solubility, stable recoverability, wide anti-interference capability, and sensitive reactions to pH fluctuations in pure aqueous solutions. SPPH-Cl has succeeded in applying to monitor the pH of volunteer urine samples based on a standard curve established in artificially simulated urine, and the detection results have accuracy comparable to pH meters. Therefore, this work provided a powerful molecule tool for detecting pH in urine samples.

6.
Crit Care ; 28(1): 115, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594724

RESUMO

BACKGROUND: Sepsis-induced myocardial injury is a serious complication of sepsis. QT prolongation is a proarrhythmic state which reflects myocardial injury in a group of heterogeneous disorders. However, the study on the clinical value of QT prolongation in sepsis is limited. METHODS: We aimed to investigate the clinical characteristics and predictors of new-onset QT prolongation in sepsis and its impact on the outcome in a multicenter retrospective cohort study. Electrocardiographic and clinical data were collected from patients with sepsis from the wards and intensive care units of four centers after exclusion of QT-influencing medications and electrolyte abnormalities. Clinical outcomes were compared between patients with and without QT prolongation (QTc > 450 ms). Multivariate analysis was performed to ascertain whether QT prolongation was an independent predictor for 30-day mortality. The factors predicting QT prolongation in sepsis were also analyzed. RESULTS: New-onset QT prolongation occurred in 235/1024 (22.9%) patients. The majority demonstrated similar pattern as type 1 long QT syndrome. Patients with QT prolongation had a higher 30-day in-hospital mortality (P < 0.001), which was also associated with increased tachyarrhythmias including paroxysmal atrial fibrillation or tachycardia (P < 0.001) and ventricular arrhythmia (P < 0.001) during hospitalization. QT prolongation independently predicted 30-day mortality (P = 0.044) after multivariate analysis. History of coronary artery disease (P = 0.001), septic shock (P = 0.008), acute respiratory (P < 0.001), heart (P = 0.021) and renal dysfunction (P = 0.013) were independent predictors of QT prolongation in sepsis. CONCLUSIONS: New-onset QT prolongation in sepsis was associated with increased mortality as well as atrial and ventricular arrhythmias, which was predicted by disease severity and organ dysfunction.


Assuntos
Síndrome do QT Longo , Sepse , Humanos , Estudos Retrospectivos , Fatores de Risco , Hospitalização , Eletrocardiografia , Síndrome do QT Longo/etiologia , Síndrome do QT Longo/tratamento farmacológico , Sepse/complicações
7.
Ann Clin Microbiol Antimicrob ; 23(1): 33, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622723

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) is a major threat to children's health, particularly in respiratory infections. Accurate identification of pathogens and AMR is crucial for targeted antibiotic treatment. Metagenomic next-generation sequencing (mNGS) shows promise in directly detecting microorganisms and resistance genes in clinical samples. However, the accuracy of AMR prediction through mNGS testing needs further investigation for practical clinical decision-making. METHODS: We aimed to evaluate the performance of mNGS in predicting AMR for severe pneumonia in pediatric patients. We conducted a retrospective analysis at a tertiary hospital from May 2022 to May 2023. Simultaneous mNGS and culture were performed on bronchoalveolar lavage fluid samples obtained from pediatric patients with severe pneumonia. By comparing the results of mNGS detection of microorganisms and antibiotic resistance genes with those of culture, sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: mNGS detected bacterial in 71.7% cases (86/120), significantly higher than culture (58/120, 48.3%). Compared to culture, mNGS demonstrated a sensitivity of 96.6% and a specificity of 51.6% in detecting pathogenic microorganisms. Phenotypic susceptibility testing (PST) of 19 antibiotics revealed significant variations in antibiotics resistance rates among different bacteria. Sensitivity prediction of mNGS for carbapenem resistance was higher than penicillins and cephalosporin (67.74% vs. 28.57%, 46.15%), while specificity showed no significant difference (85.71%, 75.00%, 75.00%). mNGS also showed a high sensitivity of 94.74% in predicting carbapenem resistance in Acinetobacter baumannii. CONCLUSIONS: mNGS exhibits variable predictive performance among different pathogens and antibiotics, indicating its potential as a supplementary tool to conventional PST. However, mNGS currently cannot replace conventional PST.


Assuntos
Antibacterianos , Pneumonia , Humanos , Criança , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Farmacorresistência Bacteriana/genética , Sequenciamento de Nucleotídeos em Larga Escala , Carbapenêmicos , Sensibilidade e Especificidade , Líquido da Lavagem Broncoalveolar
8.
BMC Urol ; 24(1): 117, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851678

RESUMO

BACKGROUND: This study investigated the relaxation effect of PGE2 on the ureter and its role in promoting calculi expulsion following calculi development. METHODS: By using immunofluorescence and Western blot, we were able to locate EP receptors in the ureter. In vitro experiments assessed the impact of PGE2, receptor antagonists, and agonists on ureteral relaxation rate. We constructed a model of ureteral calculi with flowable resin and collected ureteral tissue from postoperative side of the ureter after obstruction surgery. Western blot analysis was used to determine the protein expression levels of EP receptors and the PGE2 terminal synthase mPGES-1. Additionally, PGE2 was added to smooth muscle cells to observe downstream cAMP and PKA changes. RESULTS: The expression of EP2 and EP4 proteins in ureteral smooth muscle was verified by Western blot analysis. According to immunofluorescence, EP2 was primarily found on the cell membrane, while EP4 was found in the nucleus. In vitro, PGE2 induced concentration-dependent ureteral relaxation. Maximum diastolic rate was 70.94 ± 4.57% at a concentration of 30µM. EP2 antagonists hindered this effect, while EP4 antagonists did not. Obstructed ureters exhibited elevated mPGES-1 and EP2 protein expression (P < 0.01). Smooth muscle cells treated with PGE2 displayed increased cAMP and phosphorylated PKA. CONCLUSIONS: PGE2 binding to EP2 induces ureteral relaxation through the cAMP-PKA pathway. This will provide a new theoretical basis for the development of new therapeutic approaches for the use of PGE2 in the treatment of ureteral stones.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico , AMP Cíclico , Dinoprostona , Receptores de Prostaglandina E Subtipo EP2 , Ureter , Cálculos Ureterais , Receptores de Prostaglandina E Subtipo EP2/metabolismo , AMP Cíclico/metabolismo , Dinoprostona/metabolismo , Dinoprostona/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Animais , Ureter/metabolismo , Transdução de Sinais/fisiologia , Masculino , Relaxamento Muscular/efeitos dos fármacos , Relaxamento Muscular/fisiologia
9.
Nucleic Acids Res ; 50(D1): D93-D101, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34850139

RESUMO

Circular RNAs (circRNAs), which are single-stranded RNA molecules that have individually formed into a covalently closed continuous loop, act as sponges of microRNAs to regulate transcription and translation. CircRNAs are important molecules in the field of cancer diagnosis, as growing evidence suggests that they are closely related to pathological cancer features. Therefore, they have high potential for clinical use as novel cancer biomarkers. In this article, we present our updates to CircNet (version 2.0), into which circRNAs from circAtlas and MiOncoCirc, and novel circRNAs from The Cancer Genome Atlas database have been integrated. In total, 2732 samples from 37 types of cancers were integrated into CircNet 2.0 and analyzed using several of the most reliable circRNA detection algorithms. Furthermore, target miRNAs were predicted from the full-length circRNA sequence using three reliable tools (PITA, miRanda and TargetScan). Additionally, 384 897 experimentally verified miRNA-target interactions from miRTarBase were integrated into our database to facilitate the construction of high-quality circRNA-miRNA-gene regulatory networks. These improvements, along with the user-friendly interactive web interface for data presentation, search, and visualization, showcase the updated CircNet database as a powerful, experimentally validated resource, for providing strong data support in the biomedical fields. CircNet 2.0 is currently accessible at https://awi.cuhk.edu.cn/∼CircNet.


Assuntos
Biomarcadores Tumorais/genética , Bases de Dados Genéticas , Neoplasias/genética , RNA Circular/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , RNA Circular/classificação
10.
BMC Anesthesiol ; 24(1): 54, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321405

RESUMO

BACKGROUND: Anaesthetic methods and drugs with rapid onset, rapid recovery and better postoperative analgesia are more suitable for rapid recovery in obstetric anaesthesia. We formulated the following hypothesis: a combination of mepivacaine and ropivacaine could provide a longer analgesic effect and have more advantages in terms of rapid-recovery indicators. METHODS: A total of 180 pregnant women scheduled to undergo elective caesarean sections were randomly assigned to three surgical groups, which received 2% mepivacaine (Group M), 2% mepivacaine + 0.75% ropivacaine (Group MR) (Volume 1:1) or 0.75% ropivacaine (Group R) through an epidural catheter. The situation of postoperative analgesia and other indicators of rapid recovery were recorded. RESULTS: One hundred and fifty patients were included in the final analysis. Their demographic data were similar. The visual analogue scale (VAS) scores of Group MR and Group R were lower than Group M at 1 and 2 h after surgery both at rest and with movement (P < 0.05), and the time to first ambulation in Group MR (17.38 ± 2.06 h) and Group M (17.20 ± 2.09 h) was shorter than that in Group R (22.18 ± 1.74 h) (P < 0.05). CONCLUSION: Application of 2% mepivacaine combined with 0.75% ropivacaine for epidural anaesthesia can provide longer postoperative analgesia and earlier ambulation, these effect may be more suitable than that of 2% mepivacaine or 0.75% ropivacaine alone for caesarean section. TRIAL REGISTRATION: This study was registered at Chinese Clinical Trial Registry (Registration number: ChiCTR 2300078288; date of registration: 04/12/2023).


Assuntos
Anestesia Epidural , Mepivacaína , Humanos , Feminino , Gravidez , Ropivacaina , Anestésicos Locais , Amidas , Cesárea , Método Duplo-Cego , Estudos Prospectivos , Anestesia Epidural/métodos , Dor Pós-Operatória
11.
Ecotoxicol Environ Saf ; 272: 116080, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350215

RESUMO

BACKGROUND: Serum prostate-specific antigen (PSA) is a primary metric for diagnosis and prognosis of prostate cancer (PCa). Exposure to heavy metals, such as lead, cadmium, mercury, and zinc can impact PSA levels in PCa patients. However, it is unclear whether this effect also occurs in men without PCa, which may lead to the overdiagnosis of PCa. METHOD: Data on a total of 5089 American men who had never been diagnosed with PCa were obtained from the National Health and Nutrition Examination Survey performed from 2003-2010. The relationship between serum PSA levels (dependent variable) and concentrations of lead (µmol/L), cadmium (nmol/L), and mercury (µmol/L) were investigated with dietary zinc intake being used as a potential modifier or covariate in a weighted linear regression model and a generalized additive model. A series of bootstrapping analyses were performed to evaluate sensitivity and specificity using these models. RESULTS: Regression analyses suggested that, in general, lead, cadmium, or mercury did not show an association with PSA levels, which was consistent with the results of the bootstrapping analyses. However, in a subgroup of participants with a high level of dietary zinc intake (≥14.12 mg/day), a significant positive association between cadmium and serum PSA was identified (1.06, 95% CI, P = 0.0268, P for interaction=0.0249). CONCLUSIONS: With high-level zinc intake, serum PSA levels may rise in PCa-free men as the exposure to cadmium increases, leading to a potential risk of an overdiagnosis of PCa and unnecessary treatment. Therefore, environmental variables should be factored in the current diagnostic model for PCa that is solely based on PSA measurements. Different criteria for PSA screening are necessary based on geographical variables. Further investigations are needed to uncover the biological and biochemical relationship between zinc, cadmium, and serum PSA levels to more precisely diagnose PCa.


Assuntos
Mercúrio , Metais Pesados , Masculino , Humanos , Estados Unidos , Antígeno Prostático Específico , Cádmio , Inquéritos Nutricionais , Zinco
12.
J Formos Med Assoc ; 123(1): 55-61, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37666718

RESUMO

AIM: Ropeginterferon alfa-2b is a novel mono-pegylated proline-interferon. Its biweekly dosing schema has demonstrated tolerability and clinical efficacy for treating chronic hepatitis in previous clinical studies. This trial evaluates the pharmacokinetics of 400 µg ropeginterferon alfa-2b in patients with chronic hepatitis C virus (HCV) and provides the data to support the clinical utility of ropeginterferon alfa-2b at 400 µg. METHODS: Seventeen patients with chronic HCV genotype 2 were enrolled to receive a single injection of 400 µg ropeginterferon alfa-2b plus 14-day treatment of ribavirin. Pharmacokinetics, safety, and HCV RNA reduction/clearance were assessed. RESULTS: Tmax was 154.003 h and T1/2 was 114.273 h. The Cmax was 29.823 ng mL-1. AUClast was 9364.292 h∗ng mL-1 and AUCinf was 11084.317 h∗ng mL-1. All adverse events were mild or moderate, and there were no serious adverse events. A 1000-fold reduction in the geometric mean of HCV RNA was observed 14 d after the single injection of ropeginterferon alfa-2b. Two patients achieved clearance of HCV RNA, and the other five patients had HCV RNA levels lower than 200 IU mL-1. CONCLUSION: Ropeginterferon alfa-2b at 400 µg led to PK exposures associated with safety and notable clinical activity in patients with chronic HCV. This study suggests that ropeginterferon alfa-2b at 400 µg is an acceptable dosing regimen for treating chronic HCV and also provides supporting data for the clinical use of ropeginterferon alfa-2b at a higher starting dose for other indications.


Assuntos
Hepatite C Crônica , Polietilenoglicóis , Humanos , Antivirais/uso terapêutico , Quimioterapia Combinada , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Resultado do Tratamento , RNA Viral
13.
Arch Orthop Trauma Surg ; 144(6): 2839-2847, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38739153

RESUMO

INTRODUCTION: The choice between a cementless taper wedge stem and a fit-and-fill stem in total Hip arthroplasty (THA) for various proximal femoral morphological types has not been thoroughly evaluated. This study aimed to compare the risk of stem-related complications between these two stem types in Dorr type A, B, and C femurs. MATERIALS AND METHODS: From January 2015 through April 2021, we retrospectively reviewed 1995 cementless THA procedures. We stratified all procedures into three groups: Dorr type A (N = 360, 18.0%), B (N = 1489, 74.7%) and C (N = 146, 7.3%). The primary outcome domain was stem-related complications, including stem subsidence ≥ 3 mm, intraoperative fracture, periprosthetic fracture and aseptic stem loosening. We performed multivariate regression analysis to compare the risk of stem-related complication between the two stem types. Other factors included age, sex, body mass index, diagnosis, age-adjusted Charlson comorbidity index, stem alignment and canal fill ratio. RESULTS: The incidence of stem-related complications in the taper wedge and fit-and-fill stem groups was 4.4% (N = 15) and 6.5% (N = 107), respectively. Fit-and-fill stems showed an increased risk of stem-related complications (aOR: 9.903, 95% CI: 1.567-62.597) only in Dorr type C femurs. No significant difference in risk was observed in Dorr type A and B femurs. Furthermore, the canal fill ratio at the lesser trochanter, 2 cm and 7 cm below the lesser trochanter, did not exhibit an association with stem-related complications in any Dorr type. CONCLUSIONS: Concerning the risk of stem-related complications, the taper wedge stem was a better choice in Dorr type C femurs. However, there was no difference in risk between the taper wedge stem and fit-and-fill stem in Dorr type A and B femurs.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Complicações Pós-Operatórias , Desenho de Prótese , Humanos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Masculino , Feminino , Prótese de Quadril/efeitos adversos , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Falha de Prótese , Fêmur/cirurgia , Fatores de Risco , Adulto , Idoso de 80 Anos ou mais
14.
J Am Chem Soc ; 145(3): 1803-1810, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36638321

RESUMO

The interfacial interaction in supported catalysts is of great significance for heterogeneous catalysis because it can induce charge transfer, regulate electronic structure of active sites, influence reactant adsorption behavior, and eventually affect the catalytic performance. It has been theoretically and experimentally elucidated well in metal/oxide catalysts and oxide/metal inverse catalysts, but is rarely reported in carbon-supported catalysts due to the inertness of traditional carbon materials. Using an example of a graphdiyne-supported cuprous oxide nanocluster catalyst (Cu2O NCs/GDY), we herein demonstrate the strong electronic interaction between them and put forward a new type of electronic oxide-graphdiyne strong interaction, analogous to the concept of electronic oxide/metal strong interactions in oxide/metal inverse catalysts. Such electronic oxide-graphdiyne strong interaction can not only stabilize Cu2O NCs in a low-oxidation state without aggregation and oxidation under ambient conditions but also change their electronic structure, resulting in the optimized adsorption energy for reactants/intermediates and thus leading to improved catalytic activity in the Cu(I)-catalyzed azide-alkyne cycloaddition reaction. Our study will contribute to the comprehensive understanding of interfacial interactions in supported catalysts.

15.
Mol Cell Biochem ; 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37943469

RESUMO

Survival of olfactory mucosal mesenchymal stem cells (OM-MSCs) remains the low level in the cerebral microenvironment during intracerebral hemorrhage (ICH). This article aims to reveal the differential expression profile of ICH-stimulated OM-MSCs based on whole transcriptome sequence analysis. OM-MSCs were isolated from 6-week C57BL/6 mice. Morphology and surface markers of OM-MSCs were investigated by light microscope and flow cytometry, respectively. OM-MSCs were incubated with 20 U/mL thrombin for 24 h to mimic ICH-induced injury in vitro. Total RNA was extracted for whole transcriptome sequencing and qPCR. OM-MSCs were characterized by negative for CD45 and CD34, and positive for CD44, CD90 and CD29. Thrombin led to decrease in cell viability and increase in senescence and apoptosis in OM-MSCs. In total, 736 lncRNAs (upregulated: 393; downregulated: 343), 21 miRNAs (upregulated: 7; downregulated: 14) and 807 mRNAs (upregulated: 422; downregulated: 385) were identified. GO and KEGG pathways were enriched in protein heterodimerization activity, trans-synaptic signaling, membrane pathway, alcohol metabolic process, organic hydroxy compound biosynthesis process, secondary alcohol metabolic process, alcoholism, neutrophil extracellular trap formation, systemic lupus erythematosus, metabolic process, steroid biosynthesis and drug metabolism-cytochrome P450. 200 lncRNA-miRNA-mRNA were predicted in thrombin-induced OM-MSCs. Based on qPCR, we validated COMMD1B, MOAP1, lncRNA CAPN15, lncRNA ALDH1L2, miR-3473b and miR-1964-3p were upregulated in thrombin-stimulated OM-MSCs, and GM20431, lncRNA GAPDH and miR-122b-3p were downregulated. Our findings provide novel understanding for thrombin-induced injury in OM-MSCs. Differently-expressed RNAs can be the targets of improving therapeutic application of OM-MSCs.

16.
Environ Sci Technol ; 57(48): 20349-20359, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37942774

RESUMO

Both ozone (O3) and UV/O3 treatment processes can effectively remove organic matter in the flocculated membrane filtration concentrate from landfill leachate, but the ozonation byproducts (OBPs) generated in the processes remain unknown. Using electrospray ionization-coupled Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS), this study investigated the molecular characteristics of unknown OBPs and their formation mechanisms during the treatment of flocculated nanofiltration concentrate (FNFC) using the O3 and UV/O3 processes. The results showed that after being treated by the O3 and UV/O3 processes, the average value of the oxygen-to-carbon ratio (O/Cavg) in the FNFC organic matter increased substantially from 0.49 to 0.61-0.64 and 0.63-0.71, respectively, with an O3 dosage of 13.4-54.4 mg/min. The main OBPs were CHO and CHON compounds, which were mainly produced through oxygenation (+O2/+O3 and -H2+O2), oxidative deamination (-NH3+O2), decyclopropyl (-C3H4), and deisopropyl (-C3H6) reactions. The hydroxyl radical (•OH) can intensify these reactions, resulting in an abundance of OBPs with a high oxidation degree and low molecular weight. OBPs at five m/z values were fragmented and analyzed with tandem mass spectrometry, and abundant hydroxyl groups, carboxyl groups, and carbonyl groups were tentatively identified, presenting a potential toxicity to aquatic organisms. Due to the high molecular diversity of the OBPs in FNFC, their lower ΔGCoxo compared to natural fulvic acid, and potential toxicity, their impact on the water environment should be given more attention.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Ozônio/análise , Poluentes Químicos da Água/análise , Oxirredução , Espectrometria de Massas em Tandem , Radical Hidroxila , Purificação da Água/métodos
17.
Environ Sci Technol ; 57(20): 7709-7720, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37154621

RESUMO

To achieve carbon neutrality (i.e., net zero carbon emissions) by 2060, China must make significant changes in its socioeconomic systems, including appropriately allocating emissions responsibility. Traditional methods of delineating responsibilities (such as production-based and consumption-based accounting) can lead to double counting when applied simultaneously and therefore difficulty in determining responsibilities of different agents. An alternative approach based on economic welfare gains from environmental externalities has been refined, ensuring that the responsibilities of consumers and producers add up to the total emissions. The application of this approach to 48 countries and 31 Chinese provinces reveals that regions with less elastic supply and demand, such as Hebei in China and Russia, have higher responsibilities. Furthermore, larger externalities associated with unitary product value shift the burden of obligations from producers to consumers. Regions with high levels of wealth and carbon-intensive imports, such as Zhejiang and Guangdong in China, as well as the United States, typically have higher consumer-based accounting (CBA) emissions than production-based accounting (PBA) emissions and, as a result, redistributed responsibilities between PBA and CBA emissions. The new distribution results vary significantly from PBA or CBA emissions, indicating opportunities for more comprehensive and accessible policy goals.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/análise , China , Federação Russa , Desenvolvimento Econômico
18.
Bioorg Med Chem ; 82: 117234, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36906964

RESUMO

Cancer with low survival rates is the second main cause of death among all diseases in the world and consequently, effective antineoplastic agents are urgently needed. Allosecurinine is a plant-derived indolicidine securinega alkaloid shown bioactivity. The object of this study is to investigate synthetic allosecurinine derivatives with considerable anticancer capacity against nine human cancer cell lines as well as mechanism of action. We synthesized twenty-three novel allosecurinine derivatives and evaluated their antitumor activity against nine cancer cell lines for 72 h by MTT and CCK8 assays. FCM was applied to analyze the apoptosis, mitochondrial membrane potential, DNA content, ROS production, CD11b expression. Western blot was selected to analyze the protein expression. Structure-activity relationships were established and potential anticancer lead BA-3 which induced differentiation of leukemia cells towards granulocytosis at low concentration and apoptosis at high concentration was identified. Mechanism studies showed that mitochondrial pathway mediated apoptosis within cancer cells with cell cycle blocking was induced by BA-3. In addition, western blot assays revealed that BA-3 induced expression of the proapoptotic factor Bax, p21 and reduced the levels of antiapoptotic protein such as Bcl-2, XIAP, YAP1, PARP, STAT3, p-STAT3, and c-Myc. Collectively, BA-3 was a lead compound for oncotherapy at least in part, through the STAT3 pathway. These results were an important step in further studies on allosecurinine-based antitumor agent development.


Assuntos
Alcaloides , Antineoplásicos , Compostos Heterocíclicos de Anel em Ponte , Neoplasias , Humanos , Antineoplásicos/farmacologia , Azepinas/farmacologia , Compostos Heterocíclicos de Anel em Ponte/farmacologia , Lactonas/farmacologia , Apoptose , Alcaloides/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
19.
Bioorg Chem ; 140: 106748, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37562314

RESUMO

The practical and facile Mn(OAc)2-promoted [3+2] cycloaddition reaction of enaminones with isocyanoacetate was developed, that delivered a diversity of 3-aroyl pyrrole-2-carboxylic esters with broad substrates scope. The most of the newly synthesized compounds exhibit moderate antiproliferative activity against four cancer cells. Notably, compound 2n demonstrate the most potent activity with average IC50 values of 5.61 µM against four distinct cancer cell lines. Moreover, 2n exhibit favorable anti-migration activity and drug-like properties. The further investigation suggests that compound 2n possesses the ability to inhibit ERK5 activity and exhibits effective binding with the ERK5 protein, making it a promising candidate as a lead compound for a new class of ERK5 inhibitors discovery.


Assuntos
Antineoplásicos , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Pirróis/farmacologia , Pirróis/química , Ciclização , Ésteres/química , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Estrutura Molecular
20.
Chem Biodivers ; 20(9): e202300006, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37565513

RESUMO

This study investigated the impact of ultrasonic extraction (UE) on the structure and in vitro antibacterial activity of polysaccharides from sugarcane leaves (SLW). Native sugarcane leaf polysaccharides were treated with ultrasound (480 W) for 3 h to yield sugarcane leaf polysaccharides (SLU). Compared to SLW (33.59 kDa), the molecular weight of SLU (13.08 kDa) was significantly decreased, while the monosaccharide composition of SLU was unchanged. The results of SEM and XRD indicated that UE significantly changed the surface morphology of SLW and destroyed its inner crystalline structure. In vitro experiments showed that SLU had stronger antibacterial activity. These findings revealed that UE treatment could alter the tertiary structure of SLW but had no impact on its primary structure. Furthermore, the antibacterial activity of SLW could be greatly enhanced after UE treatment. As a bioactive additive, SLU has great application potential in functional foods, cosmetics, and pharmaceuticals.


Assuntos
Saccharum , Ultrassom , Polissacarídeos/farmacologia , Polissacarídeos/química , Antioxidantes/química , Folhas de Planta , Antibacterianos/farmacologia , Ondas Ultrassônicas
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