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1.
Elife ; 132024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365286

RESUMEN

Biofilms are complex bacterial communities characterized by a high persister prevalence, which contributes to chronic and relapsing infections. Historically, persister formation in biofilms has been linked to constraints imposed by their dense structures. However, we observed an elevated persister frequency accompanying the stage of cell adhesion, marking the onset of biofilm development. Subsequent mechanistic studies uncovered a comparable type of toxin-antitoxin (TA) module (TA-like system) triggered by cell adhesion, which is responsible for this elevation. In this module, the toxin HipH acts as a genotoxic deoxyribonuclease, inducing DNA double strand breaks and genome instability. While the second messenger c-di-GMP functions as the antitoxin, exerting control over HipH expression and activity. The dynamic interplay between c-di-GMP and HipH levels emerges as a crucial determinant governing genome stability and persister generation within biofilms. These findings unveil a unique TA system, where small molecules act as the antitoxin, outlining a biofilm-specific molecular mechanism influencing genome stability and antibiotic persistence, with potential implications for treating biofilm infections.


Asunto(s)
Antibacterianos , Biopelículas , GMP Cíclico , Inestabilidad Genómica , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Antibacterianos/farmacología , Genoma Bacteriano , Sistemas Toxina-Antitoxina/genética , Antitoxinas/metabolismo , Antitoxinas/genética , Regulación Bacteriana de la Expresión Génica , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética
2.
J Phys Chem Lett ; 15(43): 10749-10756, 2024 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-39422347

RESUMEN

Using time-dependent density functional theory and nonadiabatic molecular dynamics, we systematically investigated the effect of A-site doping on the CO2 activation and charge carrier lifetimes in SrTiO3(STO). Our simulations revealed that A-site doping significantly enhances the chemical adsorption of CO2 on SrTiO3 surfaces, which is beneficial for promoting CO2 activation. Moreover, we found that A-site doping can efficiently stabilize the lowest unoccupied molecular orbital (LUMO) of CO2 near the conduction band minimum of STO, promoting the photogenerated electron transfer from the conduction band of STO to the CO2 LUMO. Importantly, A-site doping causes a significant nonadiabatic coupling reduction and prolongs the charge recombination time by a factor of 1.86 compared to the pristine STO. Our study clarifies the influencing mechanism of A-site doping on CO2 activation and charge carrier lifetimes and suggests important principles for the design of high-performance photocatalytic semiconductors.

3.
JACS Au ; 4(9): 3427-3435, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39328750

RESUMEN

The utilization of structure distortion to modulate the electronic structure and alter catalytic properties of metallic nanomaterials is a well-established practice, but accurately identifying and comprehensively understanding these distortions present significant challenges. Ligand-stabilized metal nanoclusters with well-defined structures serve as exemplary model systems to illustrate the structure chemistry of nanomaterials, among which few studies have investigated nanocluster models that incorporate structural distortions. In this work, a novel copper hydride nanocluster, Cu42(PPh3)8(RS)4(CF3COO)10(CH3O)4H10 (Cu42; PPh3 is triphenylphosphine and RSH is 2,4-dichlorophenylthiol), with a highly twisted structure has been synthesized in a simple way. Structural analysis reveals Cu42 comprises two Cu25 units that are conjoined in a nearly orthogonal manner. The dramatic distortion in the metal framework, which is driven by multiple interactions from the surface ligands, endows the cluster with a rich array of uncoordinated metal sites on the surface. The resulting cluster, as envisioned, exhibits remarkable activity in catalyzing carbonylation of anilines. The findings from this study not only provides atomically precise insights into the structural distortions that are pertinent to nanoparticle catalysts but also underscores the potential of structurally distorted NCs as a burgeoning generation of catalysts with precise structures and outstanding performances that can be tailored for specific functions.

4.
Nutr Metab (Lond) ; 21(1): 28, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796446

RESUMEN

Metabolic syndrome (MetS) is a cluster of clinical syndromes that is closely associated with an elevated risk of developing atherosclerotic cardiovascular disease. In a series of animal experiments and clinical trials, crocus sativus and its component crocin have demonstrated promising hypoglycemic effects. However, there is currently insufficient evidence regarding their impact on cardiometabolic parameters. Our study aimed to assess the impact of Crocus sativus and crocin on glycemic control in individuals with metabolic syndrome and associated disorders, as well as their potential effects on improving cardiometabolic parameters. We searched Cochrane Library, PubMed, Embase, and Web of Science databases to ascertain the pertinent randomized controlled trials (RCTs) until December 30, 2023. Q-test and I2 statistics were utilized to evaluate heterogeneity among the included studies. Data were merged using a random-effects model and presented as (WMD) with a 95% confidence interval (CI). The current comprehensive review and meta-analysis, encompassing 13 RCTs involving a total of 840 patients diagnosed with metabolic syndrome and associated disorders, demonstrates that Crocus sativus was superior to placebo on Hemoglobin A1c(HbA1c) (WMD: -0.31;95% CI [-0.44,-0.19]. P = 0.002) and systolic blood pressure(SBP) (WMD:-7.49;95% CI [-11.67,-3.30]. P = 0.99) respectively. Moreover, Crocus sativus improved fasting blood glucose (FBG) (WMD:-7.25;95% CI [-11.82, -2.57]. P = 0.002) when used crocin and on other chronic diseases. Crocus sativus reduced the total cholesterol (TC) among the metabolic syndromepatients (WMD:-13.64;95%CI [-26.26, -1.03]. P = 0.03). We demonstrated that Crocus sativus exerts beneficial effects on glycemic control and cardiometabolic parameters in individuals with metabolic syndrome and related disorders.

5.
Phytomedicine ; 130: 155753, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795693

RESUMEN

BACKGROUND: Meningeal lymphatic vessels (mLVs) have great potential to be the therapeutic target for ß Amyloid protein (Aß) clearing in Alzheimer's disease (AD), but the regulatory methods of the mLVs are limited. The lymphatic valve, marked by FOXC2, is the fundamental structure for maintaining stable lymphatic drainage function. Preliminary evidence suggested that borneol (BO) as the classical phytochemicals could enhance the expression of FOXC2 in the mLVs of healthy mice. PURPOSE: This study aims to explore the regulatory ability of BO on lymphatic valves of mLVs in the AD model mice. STUDY DESIGN: We used the intracerebroventricular injection of Aß42 oligomers to construct the AD-like symptoms model induced by toxic protein deposition. We administered BO nano micelles(BO-Ms) orally before and after to simulate the AD prevention and treatment strategy. METHODS: Herein, this study characterized the efficacy and pathways of BO-Ms for regulating mLVs in AD model by Rt-PCR, WB and confocal microscopy, and determined the effects of BO-Ms on Aß clearance, behavior and safety of AD mice. RESULTS: The AD modeling process severely impaired the expression of lymphatic valves. However, after oral administering BO-Ms for prevention and treatment, an increase in the lymphatic valves of the transverse sinus was observed, which derived from the up-regulation of the transcription factor (FOXC2 and Akt) and the down-regulation of the transcription inhibitors (FOXO1 and PRDM1). Furthermore, the effects of BO-Ms on the lymphatic valves could enhance the lymphatic drainage of the mLVs in AD-like mice, promoting the clearance of toxicity aggregates, protecting neurons, and alleviating AD-like symptoms. Simultaneously, continuous oral BO-Ms for 30 days didn't show any significant organ toxicity. The most important thing was that the preventive effect of BO administration was superior to therapeutic administration in all data. CONCLUSION: In summary, our research indicated that BO is a promoter of lymphatic valve formation in the mLVs, and could prevent or repair damage caused by toxic Aß42. BO was the only bioactive natural product with the ability to regulate mLVs valves. Thus, BO has the potential to become phytochemicals for alleviating AD symptoms by enhancing the drainage function of mLVs.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Canfanos , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead , Animales , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/prevención & control , Enfermedad de Alzheimer/tratamiento farmacológico , Ratones , Canfanos/farmacología , Factores de Transcripción Forkhead/metabolismo , Masculino , Vasos Linfáticos/efectos de los fármacos , Meninges/efectos de los fármacos , Ratones Endogámicos C57BL
6.
Int J Mol Sci ; 25(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38612395

RESUMEN

Originally discovered in C. elegans, LIN28 is an evolutionarily conserved zinc finger RNA-binding protein (RBP) that post-transcriptionally regulates genes involved in developmental timing, stem cell programming, and oncogenesis. LIN28 acts via two distinct mechanisms. It blocks the biogenesis of the lethal-7 (let-7) microRNA (miRNA) family, and also directly binds messenger RNA (mRNA) targets, such as IGF-2 mRNA, and alters downstream splicing and translation events. This review focuses on the molecular mechanism of LIN28 repression of let-7 and current strategies to overcome this blockade for the purpose of cancer therapy. We highlight the value of the LIN28/let-7 pathway as a drug target, as multiple oncogenic proteins that the pathway regulates are considered undruggable due to their inaccessible cellular location and lack of cavities for small molecule binding.


Asunto(s)
MicroARNs , Animales , Caenorhabditis elegans/genética , Carcinogénesis , Transformación Celular Neoplásica , MicroARNs/genética , ARN Mensajero , Humanos
7.
Plant Commun ; 5(6): 100921, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38616491

RESUMEN

CRISPR-Cas-based genome editing holds immense promise for advancing plant genomics and crop enhancement. However, the challenge of low editing activity complicates the identification of editing events. In this study, we introduce multiple single transcript unit surrogate reporter (STU-SR) systems to enhance the selection of genome-edited plants. These systems use the same single guide RNAs designed for endogenous genes to edit reporter genes, establishing a direct link between reporter gene editing activity and that of endogenous genes. Various strategies are used to restore functional reporter genes after genome editing, including efficient single-strand annealing (SSA) for homologous recombination in STU-SR-SSA systems. STU-SR-base editor systems leverage base editing to reinstate the start codon, enriching C-to-T and A-to-G base editing events. Our results showcase the effectiveness of these STU-SR systems in enhancing genome editing events in the monocot rice, encompassing Cas9 nuclease-based targeted mutagenesis, cytosine base editing, and adenine base editing. The systems exhibit compatibility with Cas9 variants, such as the PAM-less SpRY, and are shown to boost genome editing in Brassica oleracea, a dicot vegetable crop. In summary, we have developed highly efficient and versatile STU-SR systems for enrichment of genome-edited plants.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Genoma de Planta , Oryza , Edición Génica/métodos , Oryza/genética , Genes Reporteros , ARN Guía de Sistemas CRISPR-Cas/genética
8.
Curr Med Imaging ; 20: 1-8, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38389370

RESUMEN

BACKGROUND: Pulmonary embolism (PE) is a relatively rare vascular complication of acute pancreatitis (AP), and its mortality rate is high. To our knowledge, relevant literature reports still need to be summarized. In this study, we analyzed the clinical characteristics, treatment, and prognosis of five patients with AP complicated by PE and summarized and reviewed the relevant literature. METHODS: Clinical data of patients with AP complicated by PE treated in Taizhou Hospital of Zhejiang Province between January 2017 and September 2022 were retrospectively collected. Combined with the relevant literature, the clinical characteristics, treatment, and prognoses of patients with AP combined with PE were analyzed and summarized. RESULTS: Five patients were eventually enrolled in this study. Among the five patients with AP complicated by PE, all (100%) had symptoms of malaise, primarily chest tightness, shortness of breath, and dyspnea. All patients (100%) had varied degrees of elevated D-dimer levels and a significant decrease in the pressure of partial oxygen (PO2) and pressure of arterial oxygen to fractional inspired oxygen concentration ratio (PaO2/FiO2). Computed tomographic angiography (CTA) or pulmonary ventilation/perfusion imaging revealed a pulmonary artery filling defect in these patients. One patient (20%) had left calf muscular venous thrombosis before the occurrence of PE. Four patients (80%) were treated with lowmolecular- weight heparin (LMWH), and one patient (20%) was treated with rivaroxaban during hospitalization; all continued oral anticoagulant therapy after discharge. All patients (100%) were cured and discharged. No patients showed recurrence of AP or PE. CONCLUSION: PE is a rare but life-threatening complication of AP. However, once diagnosed, early treatment with anticoagulation or radiological interventional procedures is effective, and the prognosis is good. Core Tips: Pulmonary embolism (PE) is a rare but life-threatening complication of acute pancreatitis (AP). Its early diagnosis and timely anticoagulation or radiological intervention can reduce mortality. However, only nine cases have been reported in the English literature thus far, and they are all case reports. Our study is the first systematic analysis of patients with AP combined with PE with a review of the relevant literature. Our patients and those reported in the literature were discharged with good prognoses under treatment such as anticoagulation and vascular intervention. These cases remind clinicians that, in patients with AP, especially those with risk factors for venous thrombosis, it is necessary to monitor the D-dimer level dynamically. Clinicians should pay attention to AP patients' symptoms and related examinations to reduce the chance of a missed diagnosis or misdiagnosis of PE.


Asunto(s)
Pancreatitis , Embolia Pulmonar , Trombosis de la Vena , Humanos , Enfermedad Aguda , Anticoagulantes/uso terapéutico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Oxígeno , Pancreatitis/complicaciones , Pancreatitis/diagnóstico por imagen , Pancreatitis/tratamiento farmacológico , Pronóstico , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico por imagen , Estudios Retrospectivos , Trombosis de la Vena/complicaciones , Trombosis de la Vena/tratamiento farmacológico
9.
J Biochem Mol Toxicol ; 38(1): e23519, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37665680

RESUMEN

Immunotherapy has developed rapidly in recent years. This study aimed to establish a prognostic signature for immune-related genes (IRGs) and explore related potential immunotherapies. The RNA-seq transcriptome profiles and clinicopathological information of patients were obtained from The Cancer Genome Atlas. Differentially expressed IRGs in tumors and normal tissues were screened and a risk score signature was constructed to predict the prognosis in patients with hepatocellular carcinoma (HCC). Receiver operating characteristic curves, survival analyses, and correlation analyses were used to explore the clinical application of this model. We further analyzed the differences in clinical characteristics, immune infiltration, somatic mutations, and treatment sensitivity between the high- and low-risk populations characterized by the prognostic models. The immune cell infiltration score and immune-related pathway activity were calculated using the single sample gene set enrichment analysis (ssGSEA) set enrichment analysis. Gene ontology (GO), Kyoto encyclopedia of genes and genomes, and GSEA were used to explore the underlying mechanisms. We constructed a nine-IRG formula to predict the prognosis in HCC patients. The higher the risk score, the higher the malignancy of the tumor and the worse the prognosis. There were significant differences in immune related processes between the high- and low-risk groups. TP53 and CTNNB1 mutations were significantly different between different risk groups. The expression of model gene was closely related to the sensitivity of tumor cells to chemotherapeutic drugs. This risk score model, which is helpful for the individualized treatment of patients with different risk factors, could be a reliable prognostic tool for HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Factores de Riesgo , Expresión Génica , Ontología de Genes
10.
Discov Med ; 35(179): 982-987, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38058063

RESUMEN

BACKGROUND: The Haptoglobin (Hp) genotypes have been linked to immune diseases and play a significant role in metabolic diseases. This study aimed to analyze the correlation between Hp gene polymorphism and the severity of hepatitis B accompanied by liver steatosis. METHODS: A total of 182 with Hepatitis B and concurrent hepatic steatosis were included in the study. Clinical biochemical indices for each participant were recorded. DNA was extracted from peripheral blood leukocytes for globin genotyping. Of these participants, 128 underwent biopsy from which histological data were collected. RESULTS: Subjects with hepatitis B and hepatic steatosis carrying the Hp 2-2 genotype exhibited elevated alanine transaminase (ALT), c-glutamyl transferase (GGT), and aspartate amino transferase (AST) levels. In contrast, high-density lipoprotein (HDL) levels and the copy number of Hepatitis B Virus (HBV)-DNA were significantly reduced in those with the Hp 2-2 genotype (p < 0.05). Furthermore, individuals processing the Hp 2-2 genotype demonstrated a heightened hepatitis score and advanced fibrosis stage (p < 0.05). Notably, the Hp 2-2 genotype was independently associated with increased inflammation (odds ratio (OR) = 7.059, p < 0.001) and progressive fibrosis (OR = 3.05, p < 0.022). CONCLUSIONS: The Hp 2-2 genotype is significantly associated with increased severity in cases of hepatitis B with coexisting hepatic steatosis.


Asunto(s)
Hígado Graso , Hepatitis B Crónica , Hepatitis B , Humanos , Haptoglobinas/genética , Haptoglobinas/metabolismo , Hígado Graso/genética , Hígado Graso/complicaciones , Hepatitis B/complicaciones , Hepatitis B/genética , Hepatitis B/metabolismo , Genotipo , Fibrosis , Hígado/patología , ADN/metabolismo , Cirrosis Hepática
11.
Phys Chem Chem Phys ; 25(47): 32622-32631, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38009229

RESUMEN

By performing nonadiabatic molecular dynamics combined with ab initio time-domain density functional theory, we have explored the effects of the charge density of a sulfur vacancy on charge trapping and recombination in antimony trisulfide (Sb2S3). The simulations demonstrate that, compared to an antimony vacancy, the sulfur vacancy generates a high charge density trap state within the band gap. This state acts as the recombination center and provides new channels for charge carrier relaxation. Filling the sulfur vacancy with electron donors elevates the defect state to the Fermi level due to the introduced extra electrons. In contrast, the electron acceptor lowers the charge density of the sulfur vacancy by capturing its local electrons, eliminating the charge recombination center and extending the photo-generated charge carrier lifetime. Additionally, compared with electron injection, hole injection can also decrease the charge density of the trap state via neutralizing its local electronic states, eliminate the trap state within the band gap, and suppress nonradiative electron-hole recombination. This study is expected to shed new light on the blocking recombination centers and provide valuable insights into the design of high-performance solar cells.

12.
iScience ; 26(10): 107850, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37752951

RESUMEN

The atomically precise metal electrocatalysts for driving CO2 reduction reactions are eagerly pursued as they are model systems to identify the active sites, understand the reaction mechanism, and further guide the exploration of efficient and practical metal nanocatalysts. Reported herein is a nanocluster-based electrocatalyst for CO2 reduction, which features a clear geometric and electronic structure, and more importantly excellent performance. The nanocatalysts with the molecular formula of [Ag17Cu10(dppm)4(PhC≡C)20H4]3+ have been obtained in a facile way. The unique metal framework of the cluster, with silver, copper, and hydride included, and dedicated surface structure, with strong (dppm) and labile (alkynyl) ligands coordinated, endow the cluster with excellent performance in electrochemical CO2 reduction reaction to CO. With the atomically precise electrocatalysts in hand, not only high reactivity and selectivity (Faradaic efficiency for CO up to 91.6%) but also long-term stability (24 h), are achieved.

13.
J Gastroenterol Hepatol ; 38(11): 1942-1948, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37403267

RESUMEN

BACKGROUND AND AIM: The relationship between Helicobacter pylori (H. pylori) and fast plasma glucose (FPG) on nondiabetes populations is still inconclusive. Nowadays, not only the high infection rate of H. pylori but also the high FPG level is threatening the Chinese people. METHODS: A retrospective cohort study has been established to analyze the relationship between H. pylori infection and FPG level, 18 164 individuals performed healthy examination in Taizhou Hospital Health Examination Center from 2017 to 2022 were included, and hematological indicators, body parameters, and H. pylori detection by 13 C-urea breath test were collected from patients. The follow-up intervals were greater than 12 months. RESULTS: H. pylori infection was regarded as an independent risk factor for elevated FPG after multivariate logistic regression. Additionally, the average interval time were 33.6 ± 13.3 months. Mean changed FPG values in the persistent infection group were higher than in the subgroup of persistent negative (P = 0.029) as well as eradication infection (P = 0.007). The aforementioned changes began to appear after 2 years of follow-up. Similarly, when compared with the subgroup of persistent infection, mean changed triglyceride/high density lipoprotein (TG/HDL) values were much lower in the subgroup of persistent negative (P = 0.008) and eradication infection (P = 0.018), but the differences appeared after 3 years of follow-up. CONCLUSIONS: H. pylori infection is an independent risk factor for elevated FPG in non-diabetes mellitus (DM) individuals. Persistent H. pylori infection causes an increase in FPG level and TG/HDL, which may be a risk factor for diabetes mellitus.


Asunto(s)
Diabetes Mellitus , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Glucemia , Estudios Retrospectivos , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/diagnóstico , Pueblos del Este de Asia , Infección Persistente , Diabetes Mellitus/epidemiología , Diabetes Mellitus/etiología , Triglicéridos , Ayuno
14.
Phys Chem Chem Phys ; 25(28): 18866-18873, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37403608

RESUMEN

Monoclinic bismuth vanadate (BiVO4) has emerged as an excellent optically active photoanode material due to its unique physical and chemical properties. Experiments reported that the low concentration of oxygen vacancies enhances the photoelectrochemical (PEC) activity of BiVO4, but the high concentration of oxygen vacancies decreases the charge carrier lifetime. Using time-domain density functional theory and molecular dynamics, we have demonstrated that the distribution of oxygen vacancies has strong effects on the static electronic structure and nonadiabatic (NA) coupling of the BiVO4 photoanode. The localized oxygen vacancies create charge recombination centers within the band gap and enhance the NA coupling between the VBM and the CBM, resulting in fast charge and energy losses. By contrast, the discrete oxygen vacancies can eliminate the charge recombination centers and decrease the NA coupling between the VBM and the CBM, enhancing the PEC activity of monoclinic BiVO4. Our study suggests that the PEC performance of a photoanode can be improved by changing the distribution of oxygen vacancies.

15.
J Phys Chem Lett ; 14(25): 5867-5875, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37341497

RESUMEN

Focusing on LaFeO3, we investigated the effects of magnetic ordering on carrier relaxation using time-domain density functional theory and nonadiabatic molecular dynamics. The results show that the hot energy and carrier relaxation occur on a sub-2 ps time scale due to the strong intraband nonadiabatic coupling, and the corresponding time scales are distinct depending on the magnetic ordering of LaFeO3. Importantly, the energy relaxation is slower than hot carrier relaxation, guaranteeing photogenerated hot carriers can be effectively relaxed to the band edge before cooling. Following hot carrier relaxation, the charge recombination occurs on the nanosecond scale due to the small interband nonadiabatic coupling and short pure-dephasing times. In addition, the A-AFM system has the longest carrier lifetimes because of its weakest nonadiabatic coupling. Our study suggests that the carrier lifetime can be controlled by changing the magnetic ordering of perovskite oxides and provides valuable principles for the design of high-performance photoelectrodes.

16.
Inorg Chem ; 62(23): 9005-9013, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37252689

RESUMEN

Manipulating the interfacial/surface structure of ligand-stabilized atomically precise metal nanoclusters (NCs) is one of the central tasks in nanoscience because surface motifs are directly related to key properties of nanomaterials. Although great progress has been made in engineering the surface of gold and silver nanoclusters, parallel studies on lighter copper analogues hitherto remain unexplored. In this work, we report the design, synthesis, and structure of a new class of copper nanoclusters featuring virtually identical kernels but different surface motifs. The four Cu29 nanoclusters share the same Cu13 kernel with unprecedented anticuboctahedral architecture. Finely modulating synthetic parameters endows the Cu13 core with diverse surface structures, thus affording the Cu29 series with labile surface coatings. More interestingly, the slight surface modification results in distinct optical and catalytic properties of the cluster compounds, highlighting the importance of the surface structure in shaping the behaviors of copper nanomolecules. This work not only exemplifies the efficiency of surface engineering for controlling properties of well-defined copper nanoclusters but also provides a new family of Cu materials with a clear molecular structure and controlled surface motifs that hold great promise in studying structure-property relationships.

17.
ISA Trans ; 141: 132-142, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37121822

RESUMEN

As an essential research task in artificial intelligence (AI), the estimation of 3D human poses has important application value in virtual reality, medical diagnosis, athlete training and other fields. However, human pose recovery and retargeting require the acquisition of detailed visual data containing private information, which has led to increasing concerns about user privacy and security. Therefore, we build a lightweight framework, called Human Motion Parameters Prediction (HMPP), which can infer the 3D mesh and 3D skeletal joint points of the human body while protecting the privacy of the user. The proposed method successfully reduces or suppresses privacy attributes while ensuring important features to perform human pose estimation. The 2D and 3D joints are used for supervision to improve the interpretability of the model at each stage. In addition, the prediction of the camera's internal parameters is added so that the model can be augmented with projection supervision, thereby using more 2D datasets for training and improving the generalization ability of the model. Finally, the predicted motion parameters are used for 3D reconstruction and motion retargeting. Experiments show that our approach can achieve excellent evaluation results on multiple datasets and avoid inadvertently compromising private and sensitive data.


Asunto(s)
Inteligencia Artificial , Privacidad , Humanos , Movimiento (Física)
18.
Immunopharmacol Immunotoxicol ; 45(5): 539-548, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36891829

RESUMEN

The A20 protein is considered to have a potent anti-inflammatory effect, but its mechanism of action in the regulation of ferroptosis and inflammation after stroke is still unknown. In this study, the A20-knockdown BV2 cell line (sh-A20 BV2) was constructed at first, and the oxygen-glucose deprivation/re-oxygenation (OGD/R) cell model was constructed. Both the BV2 and sh-A20 BV2 cells were treated with the ferroptosis inducer erastin for 48 h, the ferroptosis-related indicators were detected by western blot. The mechanism of ferroptosis was explored by western blot and immunofluorescence. Under OGD/R pressure, the oxidative stress level of sh-A20 BV2 cells was inhibited, but the secretion of the inflammatory factors TNF-α, IL-1ß, and IL-6 was significantly upregulated. And sh-A20 BV2 cells had higher expression levels of GPX4 and NLRP3 proteins under OGD/R induction. Western blot further confirmed that sh-A20 BV2 cells inhibited OGD/R-induced ferroptosis. Under the effect of erastin of the ferroptosis inducer (0-1000 nM), sh-A20 BV2 cells had higher cell viability than wild-type BV2 cells and significantly inhibited the accumulation of ROS and the level of oxidative stress damage. It was confirmed that A20 could promote the activation of the IκBα/NFκB/iNOS pathway. It was confirmed by an iNOS inhibitor that iNOS inhibition could reverse the resistance effect of BV2 cells to OGD/R-induced ferroptosis after A20 knockdown. In conclusion, this study demonstrated that inhibition of A20 mediates a stronger inflammatory response while enhancing microglial resistance by knocking down A20 in BV2 cells.


Asunto(s)
Ferroptosis , Accidente Cerebrovascular , Humanos , Microglía/metabolismo , FN-kappa B/metabolismo , Línea Celular
19.
World J Gastrointest Oncol ; 15(2): 225-239, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36908317

RESUMEN

Colorectal cancer (CRC) is the second deadliest cancer and the third-most common malignancy in the world. Surgery, chemotherapy, and targeted therapy have been widely used to treat CRC, but some patients still develop resistance to these treatments. Ferroptosis is a novel non-apoptotic form of cell death. It is an iron-dependent non-apoptotic cell death characterized by the accumulation of lipid reactive oxygen species and has been suggested to play a role in reversing resistance to anticancer drugs. This review summarizes recent advances in the prognostic role of ferroptosis in CRC and the mechanism of action in CRC.

20.
Dalton Trans ; 52(11): 3371-3377, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36810425

RESUMEN

An effective strategy is developed to synthesize a novel and stable layered Cu nanocluster using a one-pot reduction method. The cluster, with a molecular formula of [Cu14(tBuS)3(PPh3)7H10]BF4 which has been unambiguously characterized by single crystal X-ray diffraction analysis, exhibits different structures from previously reported analogues with core-shell geometries. In the absence of chiral ligands, the cluster displays intrinsic chirality owing to the non-covalent ligand-ligand interactions (e.g., C-H⋯Cu interactions and C-H⋯π interactions) to lock the central copper core. The interlacing of chiral-cluster enantiomers forms a large cavity, which lays the foundation for a series of potential applications such as drug filling and gas adsorption. Moreover, the C-H⋯H-C interactions of phenyl groups between different cluster moieties promote the formation of a dextral helix and realization of the self-assembly of nanostructures.

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