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1.
Int J Gen Med ; 17: 2001-2009, 2024.
Article in English | MEDLINE | ID: mdl-38736672

ABSTRACT

Background: Lipoprotein(a) [Lp(a)] is a well-established risk factor for ischaemic stroke (IS). It is unclear whether Lp(a) is associated with IS in patients with atrial fibrillation (AF). The aim of this study is to explore the association between the concentration of Lp(a) and the risk of IS in AF patients, hope to find the potential risk factor for the IS in AF patients. Methods: This study is a retrospective cohort study. The screened AF patients between January 2017 and July 2021 were matched at 1:1 by the propensity score matching (PSM) method in the Second Affiliated Hospital of Nanchang University. Associations between Lp(a) and ischaemic stroke were analysed using logistic regression models, stratified analysis and sensitivity analysis. Statistical analyses were conducted using IBM SPSS software. Results: The number of enrolled participates is 2258, which contains 1129 non-AF patients and 1129 AF patients. Among IS patients, the median Lp(a) concentration was higher than that of controls (17.03 vs. 15.36 mg/dL, P = 0.032). The Spearman rank-order correlation coefficients revealed significant positive relationships between IS and Lp(a) (P = 0.032). In addition, a significant increase in IS risk was associated with Lp(a) levels >30.00 mg/dL in unadjusted model [OR:1.263, 95% CI(1.046-1.523), P = 0.015], model 1 [OR:1.284, 95% CI(1.062,1.552), P = 0.010], model 2 [OR: 1.297, 95% CI(1.07,1.573). P = 0.008], and model 3 [OR: 1.290, 95% CI (1.064, 1.562). P = 0.009]. The stratified analysis indicated that this correlation was not affected by female sex [1.484 (1.117, 1.972), P = 0.006], age ≤ 60 [1.864 (1.067-3.254), P=0.029], hypertension [1.359 (1.074, 1.721), P = 0.011], or non-coronary heart disease (CHD) [1.388 (1.108, 1.738), P = 0.004]. Conclusion: High levels of Lp(a) were significantly related to IS in AF patients and may be a potential risk factor in the onset of an IS in AF patients.

2.
Chem Sci ; 15(18): 6884-6890, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38725491

ABSTRACT

A class of chiral-bridged biphenyl phosphine-carboxylate bifunctional ligands CB-Phos has been developed and successfully applied to Pd(0)-catalyzed single enantioselective C-H arylation and a one pot cascade reaction involving Suzuki cross-coupling and C-H arylation. The catalytic system provides a new and convenient way for the synthesis of versatile chiral dihydrophenanthridines with rich structures and broad functional group tolerance. Good to excellent yields with high enantioselectivities were generally achieved. The reaction mechanism of the cascade reaction was also preliminarily discussed.

3.
Exp Hematol Oncol ; 13(1): 52, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760861

ABSTRACT

BACKGROUND: Non-small cell lung cancer (NSCLC) is one of the predominant malignancies globally. Percutaneous thermal ablation (PTA) has gained widespread use among NSCLC patients, with the potential to elicit immune responses but limited therapeutic efficacies for advanced-stage disease. T-helper type 9 (Th9) cells are a subset of CD4+ effector T cells with robust and persistent anti-tumor effects. This study proposes to develop PTA-Th9 cell integrated therapy as a potential strategy for NSCLC treatment. METHODS: The therapeutic efficacies were measured in mice models with subcutaneously transplanted, recurrence, or lung metastatic tumors. The tumor microenvironments (TMEs) were evaluated by flow cytometry. The cytokine levels were assessed by ELISA. The signaling molecules were determined by quantitative PCR and Western blotting. The translational potential was tested in the humanized NSCLC patient-derived xenograft (PDX) model. RESULTS: We find that PTA combined with adoptive Th9 cell transfer therapy substantially suppresses tumor growth, recurrence, and lung metastasis, ultimately extending the survival of mice with NSCLC grafts, outperforming both PTA and Th9 cell transfer monotherapy. Analysis of TMEs indicates that combinatorial therapy significantly augments tumor-infiltrating Th9 cells, boosts anti-tumor effects of CD8+ T cells, and remodels tumor immunosuppressive microenvironments. Moreover, combinatorial therapy significantly strengthens the regional and circulation immune response of CD8+ T cells in mice with tumor lung metastasis and induces peripheral CD8+ T effector memory cells in mice with tumor recurrence. Mechanically, PTA reinforces the anti-tumor ability of Th9 cells primarily through upregulating interleukin (IL)-1ß and subsequently activating the downstream STAT1/IRF1 pathway, which could be effectively blocked by intercepting IL-1ß signaling. Finally, the enhanced therapeutic effect of combinatorial therapy is validated in humanized NSCLC PDX models. CONCLUSIONS: Collectively, this study demonstrates that combinatorial therapy displays robust and durable anti-tumor efficacy and excellent translational potential, offering excellent prospects for translation and emerging as a promising approach for NSCLC treatment.

4.
Front Nutr ; 11: 1400063, 2024.
Article in English | MEDLINE | ID: mdl-38751743

ABSTRACT

The present study demonstrated the digestion behavior and fermentation characteristics of a sulfated polysaccharide from Sargassum fusiforme (SFSP) in the simulated digestion tract environment. The results showed that the molecular weight of two components in SFSP could not be changed by simulated digestion, and no free monosaccharide was produced. This indicates that most of SFSP can reach the colon as prototypes. During the fermentation with human intestinal flora in vitro, the higher-molecular-weight component of SFSP was utilized, the total sugar content decreased by 16%, the reducing sugar content increased, and the galactose content in monosaccharide composition decreased relatively. This indicates that SFSP can be selectively utilized by human intestinal flora. At the same time, SFSP also changed the structure of intestinal flora. Compared with the blank group, SFSP significantly increased the abundance of Bacteroidetes and decreased the abundance of Firmicutes. At the genus level, the abundances of Bacteroides and Megamonas increased, while the abundances of Shigella, Klebsiella, and Collinsella decreased. Moreover, the concentrations of total short-chain fatty acids (SCFAs), acetic, propionic and n-butyric acids significantly increased compared to the blank group. SFSP could down-regulate the contents of trimethylamine, piperidone and secondary bile acid in fermentation broth. The contents of nicotinic acid, pantothenic acid and other organic acids were increased. Therefore, SFSP shows significant potential to regulate gut microbiota and promote human health.

5.
Clin Lung Cancer ; 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38705833

ABSTRACT

BACKGROUND: Immune checkpoint inhibitors have revolutionized non-small cell lung cancer (NSCLC) treatment but may pose greater technical challenges for surgery. This study aims to assess the feasibility and oncological effectiveness of video-assisted thoracoscopic surgery (VATS) for resectable stage III NSCLC after neoadjuvant immunochemotherapy. METHODS: Initial stage IIIA-IIIB NSCLC patients with neoadjuvant immunochemotherapy undergoing either VATS or open lobectomy at 6 medical centers during 2019-2023 were retrospectively identified. Perioperative outcomes and 2-year survival was analyzed. Propensity-score matching (PSM) was employed to balance patient baseline characteristics. RESULTS: Among the total 143 patients, PSM yielded 62 cases each for VATS and OPEN groups. Induction-related adverse events were comparable between the 2 groups. VATS showed a 14.5% conversion rate. Notably, VATS decreased numeric rating scales for postoperative pain, shortened chest tube duration (5[4-7] vs. 6[5-8] days, P = .021), reduced postoperative comorbidities (21.0% vs. 37.1%, P = .048), and dissected less N1 lymph nodes (5[4-6] vs. 7[5-9], P = .005) compared with thoracotomy. Even when converted, VATS achieves perioperative outcomes equivalent to thoracotomy. Additionally, over a median follow-up of 29.5 months, VATS and thoracotomy demonstrated comparable 2-year recurrence-free survival (77.20% vs. 73.73%, P = .640), overall survival (87.22% vs. 88.00%, P = .738), cumulative incidences of cancer-related death, and recurrence patterns. Subsequent subgroup comparisons and multivariate Cox analysis likewise revealed no statistical difference between VATS and thoracotomy. CONCLUSION: VATS is a viable and effective option for resectable stage III NSCLC patients following neoadjuvant immunochemotherapy, leading to decreased surgical-related pain, earlier chest tube removal, reduced postoperative complications, and similar survival outcomes compared to thoracotomy.

6.
Cell Rep Med ; : 101531, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38697105

ABSTRACT

The clinical applications of immunocytokines are severely restricted by dose-limiting toxicities. To address this challenge, here we propose a next-generation immunocytokine concept involving the design of LH05, a tumor-conditional anti-PD-L1/interleukin-15 (IL-15) prodrug. LH05 innovatively masks IL-15 with steric hindrance, mitigating the "cytokine sink" effect of IL-15 and reducing systemic toxicities associated with wild-type anti-PD-L1/IL-15. Moreover, upon specific proteolytic cleavage within the tumor microenvironment, LH05 releases an active IL-15 superagonist, exerting potent antitumor effects. Mechanistically, the antitumor efficacy of LH05 depends on the increased infiltration of CD8+ T and natural killer cells by stimulating the chemokines CXCL9 and CXCL10, thereby converting cold tumors into hot tumors. Additionally, the tumor-conditional anti-PD-L1/IL-15 can synergize with an oncolytic virus or checkpoint blockade in advanced and metastatic tumor models. Our findings provide a compelling proof of concept for the development of next-generation immunocytokines, contributing significantly to current knowledge and strategies of immunotherapy.

7.
Nat Commun ; 15(1): 3137, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605004

ABSTRACT

Laser Sintering (LS) is a type of Additive Manufacturing (AM) exploiting laser processing of polymeric particles to produce 3D objects. Because of its ease of processability and thermo-physical properties, polyamide-12 (PA-12) represents ~95% of the polymeric materials used in LS. This constrains the functionality of the items produced, including limited available colours. Moreover, PA-12 objects tend to biofoul in wet environments. Therefore, a key challenge is to develop an inexpensive route to introduce desirable functionality to PA-12. We report a facile, clean, and scalable approach to modification of PA-12, exploiting supercritical carbon dioxide (scCO2) and free radical polymerizations to yield functionalised PA-12 materials. These can be easily printed using commercial apparatus. We demonstrate the potential by creating coloured PA-12 materials and show that the same approach can be utilized to create anti-biofouling objects. Our approach to functionalise materials could open significant new applications for AM.

8.
Sci Total Environ ; 927: 172136, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38569946

ABSTRACT

To achieve the collaborative elimination of N2O and carbon of potent greenhouse pollutants from automotive mobile sources, a chemical kinetic model is developed to accurately track the heterogeneous process of carbon-catalyzed N2O reduction based on density functional theory, with experimental data used to validate the model's reliability. The influence of carbon structure, site density, and surface chemical properties on N2O catalytic reduction can be analyzed within this system. Results reveal that the free-edge site of carbon accurately describes the catalytic reduction process of N2O. Adsorption of N2O to carbon edges in O-down, N-down, or parallel orientations exhibits an exothermic process with energy barriers. The N2O with O-down reduction pathway predominates due to the limitations imposed by the unitary carbon site. As the number of active carbon atoms at carbon edges increases, the N2O reaction mode tends towards parallel and N-down pathways, resulting in a significant enhancement of N2O conversion rates and a reduction in catalytic temperatures, with the lowest achievable temperature being 300 K. Furthermore, the triplet carbon structure exhibits higher efficiency in N2O catalytic reduction compared to the singlet carbon structure, achieving a remarkable N2O conversion rate of 93.8 % within the typical temperature exhaust window of diesel engines. This study supplies a breakthrough for carbon materials as catalysts for achieving high N2O conversion rates at low cost, which is important for the collaborative catalytic elimination of N2O and carbon black pollutants.

9.
Talanta ; 274: 126068, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38599119

ABSTRACT

Water is a fundamental element for life. The highly selective and sensitive sensing of water is always attractive for mankind in activities such as physiological processes study and extraterrestrial life exploration. Fluorescent MOFs with precise channels and functional groups might specifically recognize water molecules with hydrogen-bond interaction or coordination effects and work as water sensors. As a proof of concept, herein, an amino functionalized Zn-MOF (named as complex 1) with pores that just right for water molecules to form hydrogen bond bridges is revealed for highly selective and sensitive fluorescent sensing of water. The single-crystal X-ray diffraction analysis indicates that the 3D framework of complex 1 is functionalized with free amino groups in the channels. Hydrogen bonds formed in the channel along b-axis as water bridges to connect two adjacent NH2bdc ligands and result in the restriction of intramolecular motions (RIM) which could responsible for the selective turn-on fluorescence response to water. Complex 1 exhibits high sensitive to trace amount of water in organic solvents and could be used for water detection in a wide range water contents. Take advantages of complex 1, portable sensors (complex 1@PMMA) were prepared and used in the highly sensitive water sensing.

10.
Int J Biol Macromol ; 265(Pt 1): 130911, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38492693

ABSTRACT

In this study, the solubilization and structural changes of lignin in naked oat stems were investigated under subcritical water autohydrolysis systems (170-210 °C, 0.68-1.85 MPa). In this system, Hemicellulose was preferentially hydrolyzed in the liquid water at elevated temperatures, leading to the production of acetic acid and glucuronic acid, which acidified the reaction system. Under acidic and high-temperature conditions, lignin primarily underwent degradation and condensation reactions. At autohydrolysis temperatures below 190 °C and autohydrolysis pressures below 1.22 MPa, lignin degradation was predominant, realizing a maximum lignin removal of 47.8 % and breakage of numerous ß-O-4 bonds from lignin. At autohydrolysis temperatures above 190 °C and autohydrolysis pressures above 1.22 MPa, lignin condensation dominated, with an increase in the amount of organic acids generated upon hemicellulose degradation, leading to condensation reactions with the degraded low-molecular-weight lignin. The degree of lignin condensation was positively correlated with the temperature of the reaction system. This study provides essential insights into the dynamic changes in the structure of lignin in both the hydrolysis residue and hydrolysis solution during subcritical water autohydrolysis.


Subject(s)
Lignin , Water , Lignin/chemistry , Avena , Organic Chemicals , Temperature , Hydrolysis
11.
Eur J Cardiothorac Surg ; 65(4)2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38530978

ABSTRACT

OBJECTIVES: Immune checkpoint blockades (ICB) have been proven to improve prognosis of non-small cell lung cancer in the neoadjuvant setting, while whether its perioperative use could bring extra benefit remained unidentified. We aimed to demonstrate the prognostic benefit of perioperative ICB over preoperative-only use and investigate who could benefit from this 'sandwich ICB therapy'. METHODS: Patients undergoing neoadjuvant therapy followed by surgery from 2018 to 2022 were retrospectively reviewed, and were divided into 4 groups based on the perioperative regimens: pre-ICB + post-computed tomography (CT), pre-ICB-only, pre-CT + post-ICB and pre-CT-only. Treatment-related adverse events, surgical outcomes, therapeutic response, recurrence-free survival and overall survival were compared. RESULTS: Of 214 enrolled patients with preoperative therapy, 108 underwent immunochemotherapy and 106 underwent platinum-based chemotherapy. Compared with preoperative chemotherapy, preoperative immunochemotherapy was demonstrated with significantly higher major pathologic response (57/108 vs 12/106) and pathologic complete response (35/108 vs 4/106) rates with comparable adverse events. Regarding survival, perioperative ICB significantly improved the recurrence-free survival [versus pre-CT-only hazard ratio (HR) 0.15; 95% CI 0.09-0.27; versus pre-ICB-only HR 0.36; 95% CI 0.15-0.88] and overall survival (versus pre-CT-only HR 0.24; 95% CI 0.08-0.68). In patients without major pathologic response, perioperative ICB was observed to decrease the risk of recurrence (HR 0.31; 95% CI 0.11-0.83) compared with preoperative ICB, and was an independent prognostic factor (P < 0.05) for recurrence-free survival. CONCLUSIONS: Perioperative ICB showed promising efficacy in improving pathological response and survival outcomes of resectable non-small cell lung cancer. For patients without major pathologic response after resection followed by preoperative ICB, sequential ICB treatment could be considered.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/surgery , Immune Checkpoint Inhibitors/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/surgery , Retrospective Studies , Prognosis , Neoadjuvant Therapy
12.
Int J Biol Macromol ; 265(Pt 2): 130898, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38508556

ABSTRACT

Anti-infection hydrogels have recently aroused enormous attraction, particularly in the treatment of chronic wounds. Herein, silver nanoparticle@catechol formaldehyde resin microspheres (Ag@CFRs) were fabricated by one-step hydrothermal method and subsequently encapsulated in hydrogels which were developed by Schiff base reaction between aldehyde groups in oxidized hyaluronic acid and amino groups in carboxymethyl chitosan. The developed polysaccharide hydrogel exhibited microporous structure, high swelling capacity, favorable mechanical strength, enhanced tissue adhesion and photothermal activities. Additionally, the hydrogel not only ensured long-term and high-efficiency antibacterial performance (99.9 %) toward E. coli and S. aureus, but also realized superior cytocompatibility in vitro. Moreover, based on the triple antibacterial strategies endowed by chitosan, silver nanoparticles and the photothermal properties of catechol microspheres, the composite hydrogel exhibited excellent anti-infection function, significantly downregulated inflammatory factors (TNF-α and IL-1ß) and promoted in vivo infected-wound healing. These results demonstrated that the polysaccharide hydrogel containing Ag@CFRs has great potential for infected-wounds repair.


Subject(s)
Chitosan , Metal Nanoparticles , Hydrogels/pharmacology , Silver , Escherichia coli , Microspheres , Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Catechols/pharmacology , Anti-Inflammatory Agents , Polysaccharides/pharmacology
13.
JCI Insight ; 9(6)2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38376927

ABSTRACT

Radiotherapy induces a type I interferon-mediated (T1IFN-mediated) antitumoral immune response that we hypothesized could be potentiated by a first-in-class ataxia telangiectasia mutated (ATM) inhibitor, leading to enhanced innate immune signaling, T1IFN expression, and sensitization to immunotherapy in pancreatic cancer. We evaluated the effects of AZD1390 or a structurally related compound, AZD0156, on innate immune signaling and found that both inhibitors enhanced radiation-induced T1IFN expression via the POLIII/RIG-I/MAVS pathway. In immunocompetent syngeneic mouse models of pancreatic cancer, ATM inhibitor enhanced radiation-induced antitumoral immune responses and sensitized tumors to anti-PD-L1, producing immunogenic memory and durable tumor control. Therapeutic responses were associated with increased intratumoral CD8+ T cell frequency and effector function. Tumor control was dependent on CD8+ T cells, as therapeutic efficacy was blunted in CD8+ T cell-depleted mice. Adaptive immune responses to combination therapy provided systemic control of contralateral tumors outside of the radiation field. Taken together, we show that a clinical candidate ATM inhibitor enhances radiation-induced T1IFN, leading to both innate and subsequent adaptive antitumoral immune responses and sensitization of otherwise resistant pancreatic cancer to immunotherapy.


Subject(s)
Ataxia Telangiectasia , Interferon Type I , Pancreatic Neoplasms , Pyridines , Quinolones , Animals , Mice , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/radiotherapy , Pancreatic Neoplasms/pathology , Immunity
14.
Front Oncol ; 14: 1319819, 2024.
Article in English | MEDLINE | ID: mdl-38347841

ABSTRACT

Background: Extramammary Paget's disease (EMPD) is a rare cutaneous malignancy, commonly affecting the external genitalia and perianal area of the elderly with unclear pathogenesis. Metabolomics provides a novel perspective for uncovering the metabolic mechanisms of a verity of cancers. Materials and methods: Here, we explored the metabolome of EMPD using an untargeted strategy. In order to further investigate the potential relationship between metabolites and gene expression, we re-analyzed the gene expression microarray data (GSE117285) using differential expression analysis and functional enrichment analyses. Results: Results showed that a total of 896 metabolites were identified and 87 metabolites including 37 upregulated and 50 downregulated significantly in EMPD were sought out. In the following feature selection analyses, four metabolites, namely, cyclopentyl fentanyl-d5, LPI 17:0, guanosine-3',5'-cyclic monophosphate, kynurenine (KYN, high in EMPD) were identified by both random forest and support vector machine analyses. We then identified 1,079 dysfunctional genes: 646 upregulated and 433 downregulated in EMPD. Specifically, the tryptophan-degrading enzyme including indoleamine-2,3-dioxygenase-1 (IDO1) and tryptophan 2,3-dioxygenase (TDO2) were also increased. Generally, cancers exhibit a high expression of IDO1 and TDO2 to catabolize tryptophan, generating abundant KYN. Moreover, we also noticed the abnormal activation of sustaining proliferative signaling in EMPD. Conclusion: In conclusion, this study was the first to reveal the metabolome profile of EMPD. Our results demonstrate that IDO1/TDO2-initialized KYN metabolic pathway may play a vital role in the development and progression of EMPD, which may serve as a potential therapeutic target for treating EMPD.

15.
Angew Chem Int Ed Engl ; : e202318782, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38354089

ABSTRACT

High performance solution-processable deep-blue emitters with a Commission International de l'Eclairage (CIE) coordinate of CIEy ≤ 0.08 are highly desired in ultrahigh-definition display. Although, deep-blue materials with hybridized local and charge-transfer (HLCT) excited-state feature are promising candidates, their rigidity and planar molecular structures limit their application in solution-processing technique. Herein, four novel deep-blue solution-processable HLCT emitters were first proposed by attaching rigid imide aliphatic rings as functional units onto the HLCT emitting core. The functional units not only improve solubility, enhance thermal properties and morphological stability of the emitting core, but also promote photoluminescence efficiency, balance charge carrier transport, and inhibit aggregation-caused quenching effect due to the weak electron-withdrawing property as well as steric hindrance. The corresponding solution-processable organic light-emitting diodes (OLEDs) substantiate an unprecedented maximum external quantum efficiency (EQEmax) of 11.5% with an emission peak at 456 nm and excellent colour purity (full width at half maximum = 56 nm and CIEy = 0.09). These efficiencies represent the state-of-the-art device performance among the solution-processable blue OLEDs based on the "hot exciton" mechanism. This simple strategy opens up a new avenue for designing highly efficient solution-processable deep-blue organic luminescent materials.

17.
RSC Adv ; 14(9): 6374-6384, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38380238

ABSTRACT

The radical (co)polymerization of long-chain α-olefins (C4+) to produce high molecular weight (Mw) polymers is of great importance. However, this process is currently faced with significant challenges due to the presence of less reactive allylic radicals during radical (co)polymerization, leading to oligomers or polymers with extremely low Mw (less than 1 × 104 g mol-1). Using copolymerization of 1-octene with methyl acrylate (MA) as a proof-of-concept for addressing this challenge, we present a feasible method for synthesizing high Mw α-olefin copolymers via scandium trifluoromethanesulfonate (Sc(OTf)3)-mediated radical copolymerization. In this case, copolymers of 1-octene and MA (poly(1-octene-alt-MA)) with a Mw exceeding 3 × 104 g mol-1 were successfully synthesized in the presence of Sc(OTf)3. Meanwhile, the presence of alternating 1-octene-MA sequential structures was observed. To further enhance the Mw of poly(1-octene-alt-MA), a difunctional comonomer, 1,7-octadiene, was introduced to copolymerize with 1-octene and MA. The results indicate that the incorporation of difunctional comonomer leads to a significant increase in the Mw of the copolymers synthesized. The addition of 1 mol% of 1,7-octadiene resulted in a copolymer with a remarkably high Mw of up to 13.45 × 104 g mol-1 while still maintaining a high degree of the alternating 1-octene-MA sequence (41%). The influence of polymerization parameters on the molecular weight were also investigated. Increasing the monomer concentration, reducing the dosage of initiator, and lowering the polymerization temperature have been found to be advantageous in enhancing the molecular weight. This approach has also been successfully applied to the synthesis of high molecular weight alternating copolymers of other long-chain α-olefins, including 1-hexene, 1-decene and 1-tetradecane, with methyl acrylate. In summary, this study provides a feasible method for converting "less activated" α-olefins into high Mw olefin copolymers. This approach holds significant potential for the production of value-added polyolefins, thus offering promising prospects for future applications.

18.
Int J Biol Macromol ; 261(Pt 2): 129834, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38302029

ABSTRACT

The unique stere-complex crystal formed by poly(ʟ-lactide)/poly(ᴅ-lactide) (PLLA/PDLA) has a significant impact on properties of poly-lactide materials and is considered an effective means to improve the barrier properties of poly-lactide (PLA). In this work, poly-lactide films with different aggregate structures were prepared and the relationship of aggregate structure and barrier properties were explored. The results show that the crystal structure including crystallinity and crystal forms can be controlled by adjusting the isothermal crystallization time and crystallization temperature during the molding process. PLLA/PDLA composite films contain both homochiral crystallites and stereo-complex crystallites, and there is a synergistic crystallization effect between the two of them, which provides the composite films with high crystallinity and excellent barrier properties. Compared to the PLLA with homochiral crystallites, the PLLA/PDLA composite film with only stereo-complex crystallites exhibits higher barrier properties. The linear correlation between the crystallinity and the barrier properties is weak due to the changes in crystallization behavior and then the structure of poly-lactide caused by stereo-complexation. The linear correlation between the crystallinity and the barrier properties of the blend film is strong in the low crystallinity but weak at high crystallinity. Compared to homochiral crystallites, stereo-complex crystallites exhibits lower crystallinity dependence. It has been proven that different crystal forms have different design ideas for preparing high-barrier films, but the stereo-complexation resulting from the intermolecular forces between PLLA and PDLA having complementary chemical structure, is an effective method for enhancing the barrier performances of poly-lactide sustainably.


Subject(s)
Dioxanes , Polyesters , Crystallization , Polyesters/chemistry
19.
Lipids Health Dis ; 23(1): 21, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38254149

ABSTRACT

BACKGROUND: Moyamoya disease (MMD) has attracted the attention of scholars because of its rarity and unknown etiology. METHODS: Data for this study were sourced from the Second Affiliated Hospital of Nanchang University. Regression analyses were conducted to examine the association in Lipoprotein [Lp(a)] and MMD. R and IBM SPSS were conducted. RESULTS: A cohort comprising 1012 MMD patients and 2024 controls was established through the propensity score matching method. Compared with controls, MMD patients showed higher median Lp(a) concentrations [18.5 (9.6-37.8) mg/dL vs. 14.9 (7.8-30.5) mg/dL, P < 0.001]. The odds ratios and 95% confidence intervals for Lp(a) were calculated in three models: unadjusted model, model 1 (adjusted for body mass index and systolic blood pressure), and model 2 (adjusted for model 1 plus triglyceride, C-reactive protein, homocysteine, and low-density lipoprotein cholesterol). Results were [1.613 (1.299-2.002), P < 0.001], [1.598 (1.286-1.986), P < 0.001], and [1.661 (1.330-2.074), P < 0.001], respectively. Furthermore, age, sex, or hypertension status had nothing to do with this relationship. CONCLUSIONS: Positive relationship exists between Lp(a) and MMD.


Subject(s)
Lipoprotein(a) , Moyamoya Disease , Humans , Moyamoya Disease/genetics , Body Mass Index , C-Reactive Protein
20.
Materials (Basel) ; 17(2)2024 Jan 06.
Article in English | MEDLINE | ID: mdl-38255461

ABSTRACT

Benefitting from lightweight, high strength, long life, and green recyclability, continuous fiber reinforced thermoplastic composite (CFTPC) pipes have attracted extensive interest, especially in the on-orbit additive manufacturing of structural components. However, the preparation of CFTPC pipes remains challenging due to the on-orbit limited space and high processing temperature of thermoplastic resin. Here, we report an effective approach for high performance carbon fiber/polyether-ether-ketone (CF/PEEK) thin-walled pipes via bidirectional reinforcement using the pultrusion-winding technique. The continuous fabrication of thin-walled pipes can be achieved, but the limitation by the size of core mold is also broken. The compressive and shear performance of CF/PEEK pipes with different layer designs have been studied based on experiments and simulations. With the increase in axial prepreg tape layer, the resultant CF/PEEK pipes exhibit greatly improved axial compression strength. The finite element analysis indicates that the maximum axial stress is decreased due to the axial enhancement. The flexural strength is greatly proved with pultrusion-winding cycles. The simulation confirms that the circumferential strain is effectively reduced. The high performance of bidirectional reinforced CF/PEEK pipes and the facile controllability of this approach highlight their suitability for utilization in on-orbit manufacturing of large-scale structures.

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