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1.
Pestic Biochem Physiol ; 202: 105900, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38879291

ABSTRACT

The phytopathogenic oomycete Phytophthora litchii is the culprit behind the devastating disease known as "litchi downy blight", which causes large losses in litchi production. Although fluopimomide exhibits strong inhibitory efficacy against P. litchii, the exact mechanism of resistance is still unknown. The sensitivity of 137 P. litchii isolates to fluopimomide was assessed, and it was discovered that the median effective concentration (EC50) of the fungicide had a unimodal frequency distribution with a mean value of 0.763 ± 0.922 µg/mL. Comparing the resistant mutants to the equivalent parental isolates, the resistance mutants' survival fitness was much lower. While there was no cross-resistance between fluopimomide and other oomycete inhibitors, there is a notable positive cross-resistance between fluopimomide and fluopicolide. According to the thorough investigation, P. litchii had a moderate chance of developing fluopimomide resistance. The point mutations N771S and K847N in the VHA-a of P. litchii (PlVHA-a) were present in the fluopimomide-resistant mutants, and the two point mutations in PlVHA-a conferring fluopimomide resistance were verified by site-directed mutagenesis in the sensitive P. capsici isolate BYA5 and molecular docking.


Subject(s)
Fungicides, Industrial , Phytophthora , Point Mutation , Phytophthora/drug effects , Phytophthora/genetics , Fungicides, Industrial/pharmacology , Morpholines/pharmacology , Benzamides , Pyridines
2.
ACS Appl Mater Interfaces ; 16(19): 25498-25510, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38701230

ABSTRACT

Clean, energy-free methods of cooling are an effective way to respond to the global energy crisis. To date, cooling materials using passive daytime radiative cooling (RC) technology have been applied in the fields of energy-efficient buildings, solar photovoltaic cooling, and insulating textiles. However, RC materials frequently suffer from comprehensive damage to their microstructure, resulting in the loss of their initial cooling effect in complex outdoor environments. Here, a superhydrophobic daytime passive RC porous film with environmental tolerance (SRCP film) was fabricated, which integrated strong solar reflectivity (approximately 90%), mid-infrared emissivity (approximately 0.97), and superhydrophobicity (water contact angle (WCA) of 160° and sliding angle of 3°). This study revealed that SRCP film had an average reflectivity of 14.3% higher than SiO2 particles in the 0.3-2.5 µm wavelength region, achieving a cooling effect of 13.2 °C in ambient conditions with a solar irradiance of 946 W·m-2 and a relative humidity of 74% due to the synergistic effect of effective solar reflection and thermal infrared emission. In addition, empirical results showed that the attained films possessed outstanding environmental tolerance, maintaining high WCA (156°), stable cooling effect (8.3 °C), and low SiO2 loss (less than 5.1%) after 30 consecutive days of UV irradiation and 14 days of corrosion with acidic and alkaline solutions. More importantly, this work could be flexibly prepared by various methods without the use of any fluorine-containing reagents, which greatly widens the practical application scope.

3.
Eur J Neurol ; 31(8): e16342, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38757755

ABSTRACT

BACKGROUND AND PURPOSE: Caveolin-1 (Cav-1) is reported to mediate blood-brain barrier integrity after ischaemic stroke. Our purpose was to assess the role of circulating Cav-1 levels in predicting symptomatic intracranial haemorrhage (sICH) amongst ischaemic stroke patients after endovascular thrombectomy (EVT). METHODS: Patients with large-vessel occlusive stroke after EVT from two stroke centres were prospectively included. Serum Cav-1 level was tested after admission. sICH was diagnosed according to the Heidelberg Bleeding Classification. RESULTS: Of 325 patients (mean age 68.6 years; 207 men) included, 47 (14.5%) were diagnosed with sICH. Compared with patients without sICH, those with sICH had a lower concentration of Cav-1. After adjusting for potential confounders, multivariate regression analysis demonstrated that the increased Cav-1 level was associated with a lower sICH risk (odds ratio 0.055; 95% confidence interval 0.005-0.669; p = 0.038). Similar results were obtained when Cav-1 levels were analysed as a categorical variable. Using a logistic regression model with restricted cubic splines, a linear and negative association of Cav-1 concentration was found with sICH risk (p = 0.001 for linearity). Furthermore, the performance of the conventional risk factors model in predicting sICH was substantially improved after addition of the Cav-1 levels (integrated discrimination index 2.7%, p = 0.002; net reclassification improvement 39.7%, p = 0.007). CONCLUSIONS: Our data demonstrate that decreased Cav-1 levels are related to sICH after EVT. Incorporation of Cav-1 into clinical decision-making may help to identify patients at a high risk of sICH and warrants further consideration.


Subject(s)
Caveolin 1 , Endovascular Procedures , Intracranial Hemorrhages , Ischemic Stroke , Thrombectomy , Humans , Caveolin 1/blood , Male , Female , Aged , Thrombectomy/adverse effects , Middle Aged , Intracranial Hemorrhages/blood , Intracranial Hemorrhages/etiology , Intracranial Hemorrhages/epidemiology , Endovascular Procedures/adverse effects , Ischemic Stroke/blood , Ischemic Stroke/surgery , Aged, 80 and over , Stroke/blood , Stroke/etiology , Stroke/surgery , Prospective Studies , Postoperative Complications/etiology , Postoperative Complications/blood , Postoperative Complications/epidemiology
4.
Materials (Basel) ; 17(7)2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38612034

ABSTRACT

In this study, the induction plasma spheroidization (IPS) technique was adopted to improve the microstructure and properties of the traditional agglomerated ZrO2-7wt%Y2O3 (YSZ) powders used in thermal barrier coating (TBC) applications. Compared with agglomerated YSZ powders, IPS-treated powder has a more desirable microstructure, and the overall performance of the spray powders for TBC preparation is significantly improved. Specifically, IPS-treated powder has a dense, solid, defect-free, and chemically uniform microstructure, and its apparent density, flowability, and powder strength are significantly improved, which is believed to substantially enhance the coating performance when prepared with this IPS-treated powder.

5.
J Inflamm Res ; 17: 1941-1956, 2024.
Article in English | MEDLINE | ID: mdl-38562657

ABSTRACT

Purpose: Sepsis-induced lung injury (SLI) is a serious complication of sepsis. PANoptosis, a novel form of inflammatory programmed cell death that is not yet to be fully investigated in SLI. Our research aims to screen and validate the signature genes of PANoptosis in SLI by bioinformatics and in vivo experiment. Methods: SLI-related datasets were downloaded from NCBI Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) of SLI were identified and intersected with the PANoptosis gene set to obtain DEGs related to PANoptosis (SPAN_DEGs). Then, Protein-Protein Interaction (PPI) network and functional enrichment analysis were conducted based on SPAN_DEGs. SVM-REF, LASSO and RandomForest three algorithms were combined to identify the signature genes. The Nomogram and ROC curves were performed to predict diagnostic value. Immune infiltration analysis, correlation analysis and differential expression analysis were used to explore the immunological characterization, correlation and expression levels of the signature genes. Finally, H&E staining and qRT-PCR were conducted for further verification in vivo experiment. Results: Twenty-four SPAN_DEGs were identified by intersecting 675 DEGs with the 277 PANoptosis genes. Four signature genes (CD14, GSDMD, IL1ß, and FAS) were identified by three machine learning algorithms, which were highly expressed in the SLI group, and had high diagnostic value in the diagnostic model. Moreover, immune infiltration analysis showed that most immune cells and immune-related functions were higher in the SLI group than those in the control group and were closely associated with the signature genes. Finally, it was confirmed that the cecum ligation and puncture (CLP) group mice showed significant pathological damage in lung tissues, and the mRNA expression levels of CD14, IL1ß, and FAS were significantly higher than the sham group. Conclusion: CD14, FAS, and IL1ß may be the signature genes in PANoptosis to drive the progression of SLI and involved in regulating immune processes.

6.
Clin Neurol Neurosurg ; 239: 108248, 2024 04.
Article in English | MEDLINE | ID: mdl-38507987

ABSTRACT

BACKGROUND: The trajectory of early neurological changes in patients with acute ischemic stroke has been understudied. This study aimed to investigate the association between longitudinal trajectories of stroke severity and 90-day functional outcomes in patients with acute ischemic stroke receiving endovascular treatment. METHODS: We enrolled patients from a prospective, multicenter, randomized controlled trial. The stroke severity was assessed with the National Institute of Health Stroke Scale at the pre-procedure, 24 hours, and seven days after the procedure. Group-based trajectory modeling (GBTM) was used to identify trajectories of stroke severity. Multivariable logistic regression was performed to explore the association between stroke severity markers and 90-day functional outcomes. RESULTS: Of 218 enrolled patients, 127 (58.3%) had poor functional outcomes at 90 days. We identified three trajectories of stroke severity in the GBTM: stable symptom (38.1%), symptom deterioration (17.0%), and symptom improvement (44.9%). In multivariable analyses, trajectories of stroke severity were associated with an increased risk of poor functional outcomes (symptom improvement versus symptom deterioration: odds ratio, 0.007; 95% confidence interval, 0.001-0.040; P <0.001). Reclassification indexes revealed that trajectories of stroke severity would increase the predictive ability for poor functional outcomes at 90 days. CONCLUSION: After endovascular treatment, patients would follow one of three distinct trajectories of stroke severity. Symptom deterioration trajectory was associated with an increased risk of poor functional outcomes at 90 days. TRIAL REGISTRATION NUMBER: NCT04973332.


Subject(s)
Brain Ischemia , Endovascular Procedures , Ischemic Stroke , Stroke , Humans , Ischemic Stroke/surgery , Ischemic Stroke/complications , Brain Ischemia/surgery , Brain Ischemia/complications , Prospective Studies , Thrombectomy/methods , Treatment Outcome , Stroke/surgery , Stroke/diagnosis , Endovascular Procedures/methods
7.
J Neurosurg ; : 1-7, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38552231

ABSTRACT

OBJECTIVE: The benefit-to-risk ratio of periprocedural heparin in patients treated with endovascular thrombectomy (EVT) after intravenous thrombolysis (IVT) remains unclear. This study aimed to evaluate the potential effects of periprocedural heparin on clinical outcomes of EVT after IVT. METHODS: The authors retrospectively analyzed patients from multicenter studies treated with EVT after IVT in the anterior circulation. The endpoints were unfavorable outcome (defined as modified Rankin Scale score ≥ 3 at 90 days), 90-day mortality, symptomatic intracranial hemorrhage (SICH), successful recanalization, and early neurological deterioration. Patients were divided into two groups based on whether they were treated with heparin (heparin-treated group) or not (untreated group), and the efficacy and safety outcomes were compared using multivariable logistic regression models and propensity score-matching methods. RESULTS: Among the 322 included patients (mean age 67.4 years, 54.3% male), 32% of patients received periprocedural heparin. In multivariable analyses, the administration of periprocedural heparin was a significant predictor for unfavorable outcome (OR 2.821, 95% CI 1.15-7.326; p = 0.027), SICH (OR 24.925, 95% CI 2.363-780.262; p = 0.025), and early neurological deterioration (OR 5.344, 95% CI 1.299-28.040; p = 0.029). Regarding successful recanalization and death, no significant differences between the groups were found after propensity score matching. CONCLUSIONS: The results showed that periprocedural heparin is associated with an increased risk of unfavorable outcomes and SICH in patients treated with EVT after IVT. Further studies are warranted to evaluate the utility and safety of periprocedural heparin.

8.
Angew Chem Int Ed Engl ; 63(20): e202403092, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38415808

ABSTRACT

The hydrogenolysis of oxygenates such as alcohols and ethers is central to the biomass valorization and also a valuable transformation in organic synthesis. However, a mild and efficient catalyst system for the hydrogenolysis of a large variety of alcohols and ethers with various functional groups is still underdeveloped. Here, we report an aluminum metaphosphate-supported Pt nanoparticles (Pt/Al(PO3)3) for the hydrogenolysis of a wide variety of primary, secondary, and tertiary alkyl and benzylic alcohols, and dialkyl, aryl alkyl, and diaryl ethers, including biomass-derived furanic compounds, under mild conditions (0.1-1 atm of H2, as low as 70 °C). Mechanistic studies suggested that H2 induces formation of the surface Brønsted acid sites via its cleavage by supported Pt nanoparticles. Accordingly, the high efficiency and the wide applicability of the catalyst system are attributed to the activation and cleavage of C-O bonds by the hydrogen-induced Brønsted acid sites with the assistance of Lewis acidic Al sites on the catalyst surface. The high efficiency of the catalyst implies its potential application in energy-efficient biomass valorization or fine chemical synthesis.

9.
Front Public Health ; 12: 1148705, 2024.
Article in English | MEDLINE | ID: mdl-38327578

ABSTRACT

Objectives: The present study analyzed the impact of the COVID-19 pandemic on the prevalence and incidence of new leprosy cases, as well as the diversity, distribution, and temporal transmission of Mycobacterium leprae strains at the county level in leprae-endemic provinces in Southwest China. Methods: A total of 219 new leprosy cases during two periods, 2018-2019 and 2020-2021, were compared. We genetically characterized 83 clinical isolates of M. leprae in Guizhou using variable number tandem repeats (VNTRs) and single nucleotide polymorphisms (SNPs). The obtained genetic profiles and cluster consequences of M. leprae were compared between the two periods. Results: There was an 18.97% decrease in the number of counties and districts reporting cases. Considering the initial months (January-March) of virus emergence, the number of new cases in 2021 increased by 167% compared to 2020. The number of patients with a delay of >12 months before COVID-19 (63.56%) was significantly higher than that during COVID-19 (48.51%). Eighty-one clinical isolates (97.60%) were positive for all 17 VNTR types, whereas two (2.40%) clinical isolates were positive for 16 VNTR types. The (GTA)9, (TA)18, (TTC)21 and (TA)10 loci showed higher polymorphism than the other loci. The VNTR profile of these clinical isolates generated five clusters, among which the counties where the patients were located were adjacent or relatively close to each other. SNP typing revealed that all clinical isolates possessed the single SNP3K. Conclusion: COVID-19 may have a negative/imbalanced impact on the prevention and control measures of leprosy, which could be a considerable fact for official health departments. Isolates formed clusters among counties in Guizhou, indicating that the transmission chain remained during the epidemic and was less influenced by COVID-19 preventative policies.


Subject(s)
COVID-19 , Leprosy , Humans , Mycobacterium leprae/genetics , Pandemics , DNA, Bacterial/genetics , COVID-19/epidemiology , Leprosy/epidemiology , Leprosy/microbiology , China/epidemiology
10.
Pestic Biochem Physiol ; 198: 105747, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38225090

ABSTRACT

Ametoctradin is mainly used to treat plant oomycetes diseases, but the mechanism and resistance risk of ametoctradin in Phytophthora sojae remain unknown. This study determined the ametoctradin sensitivity of 106 P. sojae isolates and found that the frequency distribution of the median effective concentration (EC50) of ametoctradin was unimodal with a mean value of 0.1743 ± 0.0901 µg/mL. Furthermore, ametoctradin-resistant mutants had a substantially lower fitness index compared with that of wild-type isolates. Although ametoctradin did not show cross-resistance to other fungicides, negative cross-resistance to amisulbrom was found. In comparison to sensitive isolates, the control efficacy of ametoctradin to resistant mutants was lower, implying a low to moderate ametoctradin resistance risk in P. sojae. All ametoctradin-resistant mutants contained a S33L point mutation in PsCytb. A system with overexpression of PsCytb in the nucleus was established. When we ectopically overexpressed S33L-harboring PsCytb, P. sojae developed ametoctradin resistance. We hypothesized that the observed negative resistance between ametoctradin and amisulbrom could be attributed to conformational changes in the binding cavity of PsCytb at residues 33 and 220.


Subject(s)
Phytophthora , Triazoles , Point Mutation , Pyrimidines , Plant Diseases/genetics
11.
Comput Biol Med ; 170: 107959, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38215619

ABSTRACT

The severity evaluation of Parkinson's disease (PD) is of great significance for the treatment of PD. However, existing methods either have limitations based on prior knowledge or are invasive methods. To propose a more generalized severity evaluation model, this paper proposes an explainable 3D multi-head attention residual convolution network. First, we introduce the 3D attention-based convolution layer to extract video features. Second, features will be fed into LSTM and residual backbone networks, which can be used to capture the contextual information of the video. Finally, we design a feature compression module to condense the learned contextual features. We develop some interpretable experiments to better explain this black-box model so that it can be better generalized. Experiments show that our model can achieve state-of-the-art diagnosis performance. The proposed lightweight but effective model is expected to serve as a suitable end-to-end deep learning baseline in future research on PD video-based severity evaluation and has the potential for large-scale application in PD telemedicine. The source code is available at https://github.com/JackAILab/MARNet.


Subject(s)
Data Compression , Parkinson Disease , Telemedicine , Humans , Parkinson Disease/diagnosis , Software
12.
Mol Neurobiol ; 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38200351

ABSTRACT

Alzheimer's disease (AD) is the most common neurodegenerative disease, with sporadic form being the predominant type. Neuroinflammation plays a critical role in accelerating pathogenic processes in AD. Mesenchymal stem cell (MSC)-derived small extracellular vesicles (MSC-sEVs) regulate inflammatory responses and show great promise for treating AD. Induced pluripotent stem cell (iPSC)-derived MSCs are similar to MSCs and exhibit low immunogenicity and heterogeneity, making them promising cell sources for clinical applications. This study examined the anti-inflammatory effects of MSC-sEVs in a streptozotocin-induced sporadic mouse model of AD (sAD). The intracisternal administration of iPSC-MSC-sEVs alleviated NLRP3/GSDMD-mediated neuroinflammation, decreased amyloid deposition and neuronal apoptosis, and mitigated cognitive dysfunction. Furthermore, it explored the role of miR-223-3p in the iPSC-MSC-sEVs-mediated anti-inflammatory effects in vitro. miR-223-3p directly targeted NLRP3, whereas inhibiting miR-223-3p almost completely reversed the suppression of NLRP3 by MSC-sEVs, suggesting that miR-223-3p may, at least partially, account for MSC-sEVs-mediated anti-inflammation. Results obtained suggest that intracisternal administration of iPSC-MSC-sEVs can reduce cognitive impairment by inhibiting NLRP3/GSDMD neuroinflammation in a sAD mouse model. Therefore, the present study provides a proof-of-principle for applying iPSC-MSC-sEVs to target neuroinflammation in sAD.

13.
Neurol Sci ; 45(5): 2047-2055, 2024 May.
Article in English | MEDLINE | ID: mdl-37973627

ABSTRACT

BACKGROUND: Huntington's disease (HD) is a rare progressive neurological disorder, and telemedicine has the potential to improve the quality of care for patients with HD. Deutetrabenazine (DTBZ) can reduce chorea symptoms in HD; however, there is limited experience with this medication in Asian countries. METHODS: Retrospective and prospective studies were employed to explore the feasibility and reliability of a video-based telemedicine system for HD patient care. Reliability was demonstrated through consistency between selected-item scores (SIS) and total motor scores (TMS) and the agreement of scores obtained from hospital and home videos. Finally, a single-centre real-world DTBZ management study was conducted based on the telemedicine system to explore the efficacy of DTBZ in patients with HD. RESULTS: There were 77 patients included in the retrospective study, and a strong correlation was found between SIS and TMS (r = 0.911, P < 0.0001), indicating good representativeness. There were 32 patients enrolled in the prospective study. The reliability was further confirmed, indicated by correlations between SIS and TMS (r = 0.964, P < 0.0001) and consistency of SIS derived from the in-person and virtual visits (r = 0.969, P < 0.0001). There were 17 patients included in the DTBZ study with a mean 1.41 (95% confidence interval, 0.37-2.46) improvement in chorea score and reported treatment success. CONCLUSIONS: A video-based telemedicine system is a feasible and reliable option for HD patient care. It may also be used for drug management as a supplementary tool for clinical visits.


Subject(s)
Chorea , Huntington Disease , Telemedicine , Tetrabenazine/analogs & derivatives , Humans , Huntington Disease/complications , Huntington Disease/drug therapy , Chorea/drug therapy , Prospective Studies , Retrospective Studies , Reproducibility of Results
14.
Nutr Metab Cardiovasc Dis ; 34(1): 112-120, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37798237

ABSTRACT

BACKGROUND AND AIM: Stroke incidence rates are rising among young adults. Liver fibrosis has recently been recognized as a risk factor for cardiovascular events and stroke in the general population. It remains unclear whether liver fibrosis influences the prognosis of stroke. We aimed to evaluate the association between liver fibrosis and stroke recurrence in young stroke patients. METHODS AND RESULTS: Young adults with first-ever ischemic stroke were enrolled from a prospective stroke registry and were followed up for stroke recurrence. Liver fibrosis was evaluated by Fibrosis-4 (FIB-4) score and was stratified into three categories. Cox regression analysis was performed to assess the relationship between liver fibrosis and stroke recurrence. Over a median follow-up of 3.1 (1.7-4.6) years, 72 (11.6%) recurrent strokes occurred among 621 patients. According to the FIB-4 score, 73 (11.7%) patients had indeterminate fibrosis, while 11 (1.8%) had advanced fibrosis. Univariate Cox analysis revealed that patients with a high FIB-4 score were more likely to experience stroke recurrence than those with a low FIB-4 score (hazard ratio 3.748, 95% confidence interval 1.359-10.332, P = 0.011). After adjusting for potential confounders in the multivariate analysis, FIB-4 score remained an independent risk factor. CONCLUSIONS: Young stroke patients with advanced liver fibrosis were at a greater risk of stroke recurrence. Evaluating liver fibrosis may provide valuable information for stroke risk stratification, and the FIB-4 score could serve as a useful tool.


Subject(s)
Ischemic Stroke , Stroke , Young Adult , Humans , Follow-Up Studies , Recurrence , Stroke/diagnosis , Stroke/epidemiology , Liver Cirrhosis/diagnosis , Liver Cirrhosis/epidemiology , Risk Factors , Fibrosis
15.
Cell Signal ; 114: 110996, 2024 02.
Article in English | MEDLINE | ID: mdl-38040402

ABSTRACT

BACKGROUND: Proteasome 26S subunit, non-ATPase 7 (PSMD7) is a deubiquitinating enzyme that is involved in the stability of ubiquitinated proteins and participates in the development of multiple types of cancer. The roles of PSMD7 and its potential mechanisms in bladder cancer (BC) remain elusive. METHODS: In this study, we identified that PSMD7 was overexpressed in BC tissues based on gene expression omnibus (GEO) database and TNMplot web. To investigate the functional role of PSMD7, two BC cell lines, T24 and 5637, were selected. The cells were transfected with vectors containing short hairpin RNAs against PSMD7 or plasmids containing full-length PSMD7 to knockdown or overexpress PSMD7. RESULTS: Our results revealed that silencing PSMD7 inhibited cell proliferation, cycle progression, migration, invasion, and promoted cell apoptosis, whereas PSMD7 overexpression led to the opposite effects in the BC cells. Mechanically, PSMD7 influenced the protein expression but not the mRNA expression of the Ras-related protein Rab-1 A (RAB1A). PSMD7 combined with RAB1A and negatively regulated its ubiquitination, indicating that PSMD7 enhanced the stability of RAB1A through post-transcriptional modification. Moreover, the rescue experiment demonstrated that RAB1A was an important downstream effector molecule of PSMD7. Besides, the negative regulation of silencing PSMD7 on tumor growth was confirmed in mice. CONCLUSIONS: Our study substantiated a novel mechanism by which PSMD7 stabilized RAB1A to accelerate the progression of BC.


Subject(s)
MicroRNAs , Urinary Bladder Neoplasms , Animals , Mice , Cell Line, Tumor , Cell Movement , Cell Proliferation/genetics , Deubiquitinating Enzymes/genetics , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , RNA, Small Interfering , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/pathology , Humans
16.
Dalton Trans ; 52(47): 17767-17775, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37981810

ABSTRACT

Herein we report the synthesis, isolation and polymerisation activity of two new zinc compounds based on a 2,6-diisopropylphenyl (Dipp) ß-diiminate (NacNac) ligand framework with zinc also ligated by an amidate (2-pyridonate or 6-methyl-2-pyridonate) unit. The compounds crystallised as either monomeric (6-Me-2-pyridonate derivative) or dimeric (2-pyridonate) species, although both were found to be monomeric in solution via1H DOSY NMR spectroscopy, which was supported by DFT calculations. These observations suggest that both complexes initiate ring-opening polymerisation (ROP) through a single-site monometallic mechanism. High molecular weight poly ε-caprolactone (PCL) was achieved via exogenous initiator-free ROP conditions with both catalysts. An increase in the 2-pyridonate initiator steric bulk (6-Me- vs. 6-H-) resulted in an improved catalytic activity, facilitating complete monomer conversion within 1 h at 60 °C. Pyridonate end-groups were observed by MALDI-ToF mass spectrometry, contrasting with previous observations for DippNacNac-Zn acetate complexes (where no acetate end groups are observed), instead this more closely resembles the reactivity of DippNacNac-Zn alkoxide complexes in ROP (where RO end groups are observed). Additional major signals in the MALDI-ToF spectra were consistent with cyclic PCL species, which are attributed to back-biting ring-closing termination steps occuring in a process facilitated by the pyridonate unit being an effective leaving group. To the best of our knowledge, these complexes represent the first examples of pyridonate, and indeed amidate, initated ROP.

17.
Biosens Bioelectron ; 240: 115660, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37683503

ABSTRACT

Endoplasmic reticulum (ER) stress can induce reactive oxygen (ROS) generation which is directly associated with the emergence of atherosclerosis. Foam cells could promote atherogenesis by inducing ER stress. To understand hypochlorite (ClO-) levels in foam cells under ER stress, novel ER-targeted ClO- activatable ratiometric fluorescence probes Rx-NE and Rx-NCE were designed using a classical rhodamine dye and coumarin dye bridge moiety as the fluorescent skeleton. Both Rx-NE and Rx-NCE demonstrated ratiometric detection capabilities for ClO-, with Rx-NCE showing better sensitivity compared to Rx-NE. The probe Rx-NCE could detect the upregulation of ClO- in foam cells under ER stress and clearly outline delineation of the boundary of atherosclerotic plaques by dual-color imaging. Importantly, the hypochlorite-activated ratiometric probe Rx-NCE had been innovatively applied to the distinction of atherosclerotic blood vessels in atherosclerosis-bearing transgenic (tg) (flk1: eGFP) zebrafish. The probe Rx-NCE is of significant value for investigating the pathological role of ER stress and atherosclerotic diseases, as well as offering new insights into the identification of atherosclerosis.


Subject(s)
Atherosclerosis , Biosensing Techniques , Animals , Fluorescent Dyes , Hypochlorous Acid , Zebrafish , Atherosclerosis/diagnostic imaging , Endoplasmic Reticulum Stress
19.
Neoplasma ; 70(3): 361-374, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37498069

ABSTRACT

Hepatocellular carcinoma (HCC) is a malignant tumor, which seriously threatens the life of patients. LncRNA SLC7A11-AS1 was reported to be abnormally expressed in HCC. Here, the functions and relative molecular regulatory mechanism of SLC7A11-AS1 in HCC were investigated. Nude mice and HCC cells were used as the experimental subjects. Knockdown or overexpression of exogenous genes was conducted in HCC cells. RT-qPCR, IHC, and western blot were employed to evaluate the abundance of genes and proteins. The malignant behaviors were evaluated using CCK-8, clone formation, wound-healing, and Transwell. The locations of SLC7A11-AS1 and KLF9 in cells were determined by FISH and IF assays. The total m6A level was evaluated by dot-blot assay. m6A modification of SLC7A11-AS1 was detected using RNA MeRIP. The interactions among molecules were validated by RIP, ChIP, dual luciferase reporter assay, and co-IP. SLC7A11-AS1 was elevated apparently in HCC cells and HCC tissues from mice. SLC7A11-AS1 silencing could suppress HCC progression, which was validated in in vivo and in vitro experiments. Furthermore, METTL3 mediated m6A modification of SLC7A11-AS1 to elevate its expression. In addition, SLC7A11-AS1 downregulated KLF9 expression by affecting STUB1-mediated ubiquitination degradation and KLF9 enhanced PHLPP2 expression to inactivate the AKT pathway. Eventually, rescue experiments revealed that KLF9 knockdown abolished SLC7A11-AS1 silencing-mediated suppression of HCC progression in vivo and in vitro. Our results unveiled that m6A-modified SLC7A11-AS1 promoted HCC progression by regulating the STUB1/KLF9/PHLPP2/AKT axis, indicating that targeting SLC7A11-AS1 might alleviate HCC progression.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , MicroRNAs , RNA, Long Noncoding , Animals , Mice , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Liver Neoplasms/pathology , Mice, Nude , MicroRNAs/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Humans
20.
Org Lett ; 25(31): 5880-5884, 2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37498083

ABSTRACT

Bromo-functionalized B1-polycyclic aromatic hydrocarbons (PAHs) with LUMOs of less than -3.0 eV were synthesized and used in cross-couplings to form donor-acceptor materials. These materials spanned a range of S1 energies, with a number showing thermally activated delayed fluorescence and significant emission in the near-infrared region of the spectrum. These B1-PAHs represent a useful family of acceptors that can be readily synthesized and functionalized.

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