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1.
Int Immunopharmacol ; 128: 111487, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38183911

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune disease that affects joints, causing inflammation, synovitis, and erosion of cartilage and bone. Periplogenin is an active ingredient in the anti-rheumatic and anti-inflammatory herb, cortex periplocae. We conducted a study using a CIA model and an in vitro model of fibroblast-like synoviocytes (FLS) induced by Tumor Necrosis Factor-alpha (TNF-α) stimulation. We evaluated cell activity, proliferation, and migration using the CCK8 test, EDU kit, and transwell assays, as well as network pharmacokinetic analysis of periplogenin targets and RA-related effects. Furthermore, we measured inflammatory factors and matrix metalloproteinases (MMPs) expression using ELISA and qRT-PCR assays. We also evaluated joint destruction using HE and Safranin O-Fast Green Staining and examined the changes in the JAK2/3-STAT3 pathway using western blot. The results indicated that periplogenin can effectively inhibit the secretion of inflammatory factors, suppress the JAK2/3-STAT3 pathway, and impede the proliferation and migration of RA FLS. Thus, periplogenin alleviated the Synovial inflammatory infiltration of RA.


Subject(s)
Arthritis, Experimental , Arthritis, Rheumatoid , Digitoxigenin/analogs & derivatives , Synoviocytes , Humans , Animals , Inflammation/metabolism , Cell Proliferation , Fibroblasts , Synovial Membrane/pathology , Cells, Cultured , Janus Kinase 2/metabolism , STAT3 Transcription Factor/metabolism
2.
Int J Surg ; 110(2): 965-973, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38016131

ABSTRACT

BACKGROUND: Previous studies report that intraoperative hypotension worsens outcomes after aneurysmal subarachnoid hemorrhage (aSAH). However, the hypotensive harm threshold for major adverse cardiovascular events (MACE) remains unclear. METHODS: The authors included aSAH patients who had general anesthesia for aneurysmal clipping/coiling. MACE were defined by a composite of acute myocardial injury, acute myocardial infarction, and other cardiovascular complications identified by electrocardiogram and echocardiography. The authors initially used logistic regression and change-point analysis based on the second derivative to identify mean arterial pressure (MAP) of 75 mmHg as the harm threshold. Thereafter, our major exposure was MAP below 75 mmHg characterized by area, duration, and time-weighted average. The area below 75 mmHg represents the severity and duration of exposure and was defined as the sum of all areas below a specified threshold using the trapezoid rule. Time-weighted average MAP was derived by dividing area below the threshold by the duration of anesthesia. All analyses were adjusted for baseline risk factors including age greater than 70 years, female sex, severity of intracerebral hemorrhage, history of cardiovascular disease, and preoperative elevated myocardial enzymes. RESULTS: Among 1029 patients enrolled, 254 (25%) developed postoperative MACE. Patients who experienced MACE were slightly older (59±11 vs. 54±11 years), were slightly more often women (69 vs. 58%), and had a higher prevalence of cardiovascular history (65 vs. 47%). Adjusted cardiovascular risk increased nearly linearly over the entire range of observed MAP. However, there was a slight inflexion at MAP of 75 mmHg. MACE was significantly associated with area [adjusted odds ratios (aOR) 1.004 per 10 mmHg.min, 95% CI: 1.001-1.007, P =0.002), duration (aOR 1.031 per 10 min, 95% CI: 1.009-1.054, P =0.006), and time-weighted average (aOR 3.516 per 10 mmHg, 95% CI: 1.818-6.801, P <0.001) of MAP less than 75 mmHg. CONCLUSIONS: Lower blood pressures were associated with cardiovascular complications over the entire observed range, but worsened when MAP was less than 75 mmHg. Pending trial data to establish causality, it may be prudent to keep MAP above 75 mmHg in patients having surgical aSAH repairs to reduce the risk of MACE.


Subject(s)
Hypotension , Myocardial Infarction , Subarachnoid Hemorrhage , Humans , Female , Aged , Blood Pressure , Subarachnoid Hemorrhage/complications , Subarachnoid Hemorrhage/surgery , Retrospective Studies , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Hypotension/epidemiology , Intraoperative Complications/epidemiology
3.
J Clin Anesth ; 92: 111285, 2024 02.
Article in English | MEDLINE | ID: mdl-37857168

ABSTRACT

STUDY OBJECTIVES: Tranexamic acid (TXA) is an antifibrinolytic that is widely used to reduce surgical bleeding. However, TXA occasionally causes seizures and the risk might be especially great after neurosurgery. We therefore tested the hypothesis that TXA does not meaningfully increase the risk of postoperative seizures within 7 days after intracranial tumor resections. DESIGN: Randomized, double-blind, placebo-controlled, non-inferiority trial. SETTING: Beijing Tiantan Hospital, Capital Medical University. PATIENTS: 600 patients undergoing supratentorial meningioma resection were included from October 2020 to August 2022. INTERVENTIONS: Patients were randomly assigned to a single dose of 20 mg/kg of TXA after induction (n = 300) or to the same volume of normal saline (n = 300). MEASUREMENT: The primary outcome was postoperative seizures occurring within 7 days after surgery, analyzed in both the intention-to-treat and per-protocol populations. Non-inferiority was defined by an upper limit of the 95% confidence interval for the absolute difference being <5.5%. Secondary outcomes included incidence of non-epileptic complication within 7 days, changes in hemoglobin concentration, estimated intraoperative blood loss. Post hoc analyses included the types and timing of seizures, oozing assessment, and a sensitivity analysis for the primary outcome in patients with pathologic diagnosis of meningioma. MAIN RESULTS: All 600 enrolled patients adhered to the protocol and completed the follow-up for the primary outcome. Postoperative seizures occurred in 11 of 300 (3.7%) of patients randomized to normal saline and 13 of 300 (4.3%) patients assigned to tranexamic acid (mean risk difference, 0.7%; 1-sided 97.5% CI, -∞ to 4.3%; P = 0.001 for noninferiority). No significant differences were observed in any secondary outcome. Post hoc analysis indicated similar amounts of oozing, calculated blood loss, recurrent seizures, and timing of seizures. CONCLUSION: Among patients having supratentorial meningioma resection, a single intraoperative dose of TXA did not significantly reduce bleeding and was non-inferior with respect to postoperative seizures after surgery. REGISTRY INFORMATION: This trial was registered at clinicaltrials.gov (NCT04595786) on October 22, 2020, by Dr.Yuming Peng.


Subject(s)
Antifibrinolytic Agents , Meningeal Neoplasms , Meningioma , Tranexamic Acid , Humans , Antifibrinolytic Agents/adverse effects , Blood Loss, Surgical/prevention & control , Double-Blind Method , Meningeal Neoplasms/surgery , Meningeal Neoplasms/drug therapy , Meningioma/surgery , Saline Solution , Seizures/chemically induced , Seizures/epidemiology , Tranexamic Acid/adverse effects
4.
J Phys Chem Lett ; 14(46): 10361-10368, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37948649

ABSTRACT

Functional nanomaterials made by chiral induction have attracted extensive attention because of their intriguing characteristics and potential applications. However, the precise and controllable fabrication of chiral nanomaterials still remains challenging but is highly desired. In this study, chiral unimolecular micelles with different molecular weights and chiroptical activities were prepared by photoinduced atom transfer radical polymerization (photoATRP). Through nanoconfined growth, the chiral plasmonic nanoparticle assemblies with predesigned size and morphology were prepared using chiral unimolecular micelles as nanoreactors. The controllability over chiral assemblies and the size effect on chiroptical properties were also investigated. Furthermore, chiral complexes with absorption asymmetry and circularly polarized luminescence (glum = 4.25 × 10-4) were easily constructed via mixing of organic fluorescent molecules and chiral templates based on intermolecular hydrogen bonds. Such results indicated that our unimolecular-micelle-based templates enable the controllable preparation of both inorganic and organic chiral nanostructures with tailored dimensions, sizes, compositions, and optical activities.

5.
ACS Omega ; 8(35): 32159-32167, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37692212

ABSTRACT

Traditional transparent polymer nanocomposites combined with functional fluorescent inorganic nanofillers are promising for many advanced optical applications. However, the aggregation of the incorporated functional nanoparticles results in light scattering and will decrease the transparency of nanocomposites, which will restrain the application of the transparent nanocomposites. Herein, a robust synthesis strategy was proposed to modify upconversion nanoparticles (UCNPs) with polymethyl methacrylate (PMMA) to form UCNP@PMMA core@shell nanocomposites though metal-free photoinduced surface-initiated atom transfer radical polymerization (photo-SI-ATRP), and thus, the dispersity of UCNP@PMMA and the interface compatibility between the surface of UCNPs and the bulk PMMA matrix was greatly improved. The obtained PMMA nanocomposites possess high transparency and show strong upconversion photoluminescence properties, which promises great opportunities for application in 3D display and related optoelectronic fields. This strategy could also be applied to fabricate other kinds of functional transparent polymer nanocomposites with inorganic nanoparticles uniformly dispersed.

6.
Trials ; 24(1): 607, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37743486

ABSTRACT

INTRODUCTION: Postoperative delirium (POD) is a common complication, and it has a high incidence in neurosurgery patients. Awake craniotomy (AC) has been widely performed in patients with glioma in eloquent and motor areas. Most of the surgical procedure is frontotemporal craniotomy, and the operation duration has been getting longer. Patients undergoing AC are high-risk populations for POD. Dexmedetomidine (Dex) administration perioperatively might help to reduce the incidence of POD. The purpose of this study is to investigate the effect of Dex on POD in patients undergoing AC. METHODS: The study is a prospective, single-center, double-blinded, paralleled-group, randomized controlled trial. Patients undergoing elective AC will be randomly assigned to the Dex group and the control group. Ten minutes before urethral catheterization, patients in the Dex group will be administered with a continuous infusion at a rate of 0.2 µg/kg/h until the end of dural closure. In the control group, patients will receive an identical volume of normal saline in the same setting. The primary outcome will be the cumulative incidence and severity of POD. It will be performed by using the confusion assessment method in the first 5 consecutive days after surgery. Secondary outcomes include quality of intraoperative awareness, stimulus intensity of neurological examination, pain severity, quality of recovery and sleep, and safety outcomes. DISCUSSION: This study is to investigate whether the application of Dex could prevent POD in patients after undergoing AC and will provide strong evidence-based clinical practice on the impact of intraoperative interventions on preventing POD in AC patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05195034. Registered on January 18, 2022.


Subject(s)
Dexmedetomidine , Emergence Delirium , Humans , Craniotomy/adverse effects , Dexmedetomidine/therapeutic use , Prospective Studies , Randomized Controlled Trials as Topic , Wakefulness
7.
PLoS One ; 18(8): e0290725, 2023.
Article in English | MEDLINE | ID: mdl-37651373

ABSTRACT

INTRODUCTION: Tranexamic acid (TXA) has been proven to prevent thrombolysis and reduce bleeding and blood transfusion requirements in various surgical settings. However, the optimal dose of TXA that effectively reduce intraoperative bleeding and blood product infusion in patients undergoing neurosurgical resection of meningioma with a diameter ≥ 5 cm remains unclear. METHODS: This is a single-center, randomized, double-blinded, paralleled-group controlled trial. Patients scheduled to receive elective tumor resection with meningioma diameter ≥ 5 cm will be randomly assigned the high-dose TXA group, the low-dose group, and the placebo. Patients in the high-dose TXA group will be administered with a loading dose of 20 mg/kg TXA followed by continuous infusion TXA at a rate of 5 mg/kg/h. In the low-dose group, patients will receive the same loading dose of TXA followed by a continuous infusion of normal saline. In the control group, patients will receive an identical volume of normal saline. The primary outcome is the estimated intraoperative blood loss calculated using the following formula: collected blood volume in the suction canister (mL)-the volume of flushing (mL) + the volume from the gauze tampon (mL). Secondary outcomes include calculated intraoperative blood loss, intraoperative coagulation function assessed using thromboelastogram (TEG), intraoperative cell salvage use, blood product infusion, and other safety outcomes. DISCUSSION: Preclinical studies suggest that TXA could reduce intraoperative blood loss, yet the optimal dose was controversial. This study is one of the early studies to evaluate the impact of intraoperative different doses infusion of TXA on reducing blood loss in neurological meningioma patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05230381. Registered on February 8, 2022.


Subject(s)
Meningeal Neoplasms , Meningioma , Tranexamic Acid , Humans , Blood Loss, Surgical/prevention & control , Tranexamic Acid/therapeutic use , Meningioma/surgery , Saline Solution , Meningeal Neoplasms/surgery , Brain , Randomized Controlled Trials as Topic
8.
Polymers (Basel) ; 15(13)2023 Jun 22.
Article in English | MEDLINE | ID: mdl-37447426

ABSTRACT

Anisotropic thermally conductive composites are very critical for precise thermal management of electronic devices. In this work, in order to prepare a composite with significant anisotropic thermal conductivity, polyamide 12/styrene-acrylic copolymer-boron nitride (PA12/SA-BN) composites with macro and micro double anisotropic structures were fabricated successfully using 3D printing and micro-shear methods. The morphologies and thermally conductive properties of composites were systematically characterized via SEM, XRD, and the laser flash method. Experimental results indicate that the through-plane thermal conductivity of the composite is 4.2 W/(m·K) with only 21.4 wt% BN, which is five times higher than that of the composite with randomly oriented BN. Simulation results show that the macro-anisotropic structure of the composite (caused by the selective distribution of BN) as well as the micro-anisotropic structure (caused by the orientation structure of BN) both play critical roles in spreading heat along the specified direction. Therefore, as-obtained composites with double anisotropic structures possess great potential for the application inefficient and controllable thermal management in various fields.

9.
Curr Dev Nutr ; 7(7): 101959, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37408980

ABSTRACT

Enzyme-linked i2mmunosorbent assays (ELISAs) that measure circulating phylloquinone have become commercially available, but their validity is uncertain. The objective of this study was to compare plasma phylloquinone concentrations measured using two commercially available ELISAs with concentrations measured using a validated high-performance liquid chromatography (HPLC) assay in 108 samples obtained from participants in a depletion (∼10 mcg phylloquinone/d)-supplementation (∼500 mcg phylloquinone/d) study. The geometric mean of plasma phylloquinone measured with ELISA A was 0.70 nmol/L, 37% lower than that measured with HPLC. The mean of the ELISA B measures was 12.4 nmol/L, >700% higher than the HPLC measures. Plasma phylloquinone measured using HPLC was significantly lower during phylloquinone depletion than supplementation (0.4 ± 0.1 compared with 1.2 ± 0.2 nmol/L; P < 0.001). Neither of the two ELISAs detected any significant difference in plasma phylloquinone concentrations between depletion and supplementation (ELISA A, P = 0.76; ELISA B, P = 0.29). These findings reinforce the need to validate plasma phylloquinone assays as they become available. Curr Dev Nutr 2023;x:xx.

10.
Plants (Basel) ; 12(12)2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37375960

ABSTRACT

Circular RNAs (circRNAs) serve as covalently closed single-stranded RNAs and have been proposed to influence plant development and stress resistance. Grapevine is one of the most economically valuable fruit crops cultivated worldwide and is threatened by various abiotic stresses. Herein, we reported that a circRNA (Vv-circPTCD1) processed from the second exon of the pentatricopeptide repeat family gene PTCD1 was preferentially expressed in leaves and responded to salt and drought but not heat stress in grapevine. Additionally, the second exon sequence of PTCD1 was highly conserved, but the biogenesis of Vv-circPTCD1 is species-dependent in plants. It was further found that the overexpressed Vv-circPTCD1 can slightly decrease the abundance of the cognate host gene, and the neighboring genes are barely affected in the grapevine callus. Furthermore, we also successfully overexpressed the Vv-circPTCD1 and found that the Vv-circPTCD1 deteriorated the growth during heat, salt, and drought stresses in Arabidopsis. However, the biological effects on grapevine callus were not always consistent with those of Arabidopsis. Interestingly, we found that the transgenic plants of linear counterpart sequence also conferred the same phenotypes as those of circRNA during the three stress conditions, no matter what species it is. Those results imply that although the sequences are conserved, the biogenesis and functions of Vv-circPTCD1 are species-dependent. Our results indicate that the plant circRNA function investigation should be conducted in homologous species, which supports a valuable reference for further plant circRNA studies.

11.
Curr Dev Nutr ; 7(3): 100049, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37181928

ABSTRACT

Background: Evidence suggests that natural metabolites produced by intestinal microorganisms may have beneficial or harmful effects on osteoarthritis (OA). This could include menaquinones, which are bacterially-synthesized, biologically-active vitamin K forms abundant in the intestinal microbiome. Objectives: The overall goal of this study was to evaluate the association of intestinally-derived menaquinones with obesity-related OA. Methods: This case-control study used data and biospecimens derived from a subgroup of Johnston County Osteoarthritis Study participants. Fecal menaquinone concentrations and microbial composition were determined in 52 obese participants with hand and knee OA and 42 age- and sex-matched obese participants without OA. The inter-relationships among fecal menaquinones were evaluated using principal component analysis. The differences in alpha and beta diversities and microbial composition across menaquinone clusters were evaluated using ANOVA. Results: The samples were clustered into the following 3 groups: cluster 1 characterized by higher fecal menaquinone-9 and -10 concentrations, cluster 2 characterized by lower overall menaquinone concentrations, and cluster 3 characterized by higher menaquinone-12 and -13 concentrations. Overall, fecal menaquinone clusters did not differ between participants with or without OA (P = 0.707). Microbial diversity did not differ across the fecal menaquinone clusters (all F-test P > 0.12). However, the relative abundance of bacterial taxa differed among clusters, with higher abundance of Coprococcus, Prevotella, and Eggerthella in cluster 2 than in cluster 1; higher abundance of Oscillospira, Dorea, Eubacterium, and Bacteroides in cluster 3 than in cluster 1; and higher abundance of Prevotella, Sutterella, and Dorea in cluster 3 than in cluster 2 (all P < 0.001). Conclusion: Menaquinones were variable and abundant in the human gut, but the fecal menaquinone clusters did not differ with OA status. Although the relative abundance of specific bacterial taxa differed among fecal menaquinone clusters, the relevance of these differences with respect to vitamin K status and human health is uncertain.

12.
J Phys Chem Lett ; 14(21): 5077-5084, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37227451

ABSTRACT

Highly ordered TiO2 nanotube arrays (TNTAs) and their heterostructure nanocomposites by structural engineering design were utilized as heterogeneous photocatalysts for highly efficient broadband photoinduced controlled radical polymerization (photoCRP), including photoATRP and PET-RAFT. Highly efficient broadband UV-visible light responsive photoCRP was achieved by combining the acceleration effects of electron transfer derived from the distinctive highly ordered nanotube structure of TNTAs and the localized surface plasmon resonance (LSPR) effect combined with the formation of the Schottky barrier via modification of Au nanoparticles. This polymerization system was capable to polymerize acrylate and methacrylate monomers with high conversion, "living" chain-ends, tightly regulated molecular weights, and outstanding temporal control properties. The heterogeneous nature of the photocatalysts enabled simple separation and effective reusability in subsequent polymerizations. These results highlight the modular design of highly efficient catalysts to optimize the controlled radical polymerization process.

13.
J Immunol Res ; 2023: 2340538, 2023.
Article in English | MEDLINE | ID: mdl-37252680

ABSTRACT

Dysregulation of microRNAs (miRNAs) is associated with the pathogenesis of rheumatoid arthritis (RA). Our previous studies confirmed that Duanteng Yimu decoction (DTYMT) effectively inhibits RA fibroblast-like synoviocyte (FLS) proliferation. In this study, we investigated the influence of DTYMT on miR-221 in RA individuals. Hematoxylin-eosin (HE) staining was performed to assess histopathological alterations in collagen-induced arthritis (CIA) mice. The expression of miR-221-3p and TLR4 in PBMC, FLS, and cartilage was measured by RT-qPCR. In the in vitro experiments, DTYMT-containing serum was incubated with FLS-transfected miR-221 mimic or inhibitor. CCK-8 was performed to determine FLS proliferation, and the secretion of IL-1ß, IL-6, IL-18, and TNF-α was quantified by ELISA assay. In addition, the regulation of miR-221 expression on FLS apoptosis was assessed using flow cytometry. Finally, western blot was employed to reflect TLR4/MyD88 protein levels. HE results showed that DTYMT effectively reduced synovial hyperplasia in the joints of CIA mice. RT-qPCR assay of FLS and cartilage of the model group showed that miR-221-3p and TLR4 significantly increased compared with those in the normal group. All outcomes were improved by DTYMT. The miR-221 mimic reversed the inhibitory effect of DTYMT-containing serum on FLS proliferation, the release of IL-1ß, IL-18, IL-6, and TNF-α, and FLS apoptosis, as well as TLR4/MyD88 protein levels. The results showed that miR-221 promotes the activity of RA-FLS by activating TLR4/MyD88 signaling, and DTYMT treats RA by reducing miR-221 in CIA mice.


Subject(s)
Arthritis, Experimental , Arthritis, Rheumatoid , MicroRNAs , Synoviocytes , Animals , Mice , Interleukin-18/metabolism , Toll-Like Receptor 4/metabolism , Hyperplasia/drug therapy , Hyperplasia/metabolism , Hyperplasia/pathology , Interleukin-6/metabolism , Tumor Necrosis Factor-alpha/metabolism , Leukocytes, Mononuclear/metabolism , Myeloid Differentiation Factor 88/metabolism , Cell Proliferation , Arthritis, Rheumatoid/metabolism , Synoviocytes/metabolism , MicroRNAs/metabolism , Arthritis, Experimental/pathology , Fibroblasts/metabolism , Synovial Membrane/pathology , Cells, Cultured
14.
Heliyon ; 9(5): e15867, 2023 May.
Article in English | MEDLINE | ID: mdl-37206012

ABSTRACT

Background: Rheumatoid arthritis (RA) is a chronic immune disease characterised by synovitis and cartilage destruction. Currently, many patients experience poor remission after new antirheumatic drug treatments. Duanteng-Yimu Tang (DTYMT), a traditional Chinese medicine, is effective in the treatment of RA. In this research, we designed to investigate the anti-RA effects of DTYMT and explore its potential mechanisms. Methods: Network pharmacology was adopted to explore the main pathways of DTYMT in patients with RA. Collagen-induced arthritis models of male DBA/1 mice were established, and their histopathological changes were observed by hematoxylin-eosin staining and micro-CT. qRT-PCR was performed to detect the expression of Foxp3 and RORγt in the serum and synovial tissue and IL-17, IL-1ß, TNF-α, and IL-10 mRNA in vivo. The proliferation and invasion of synovial cells were analyzed using Cell Counting Kit-8 and transwell assays, respectively. The ratio of T helper 17 (Th17) to regulatory T (Treg) cells was analyzed by flow cytometry. Results: Network pharmacology analysis revealed that Th17 cell differentiation may be the key pathway of DTYMT in RA. DTYMT ameliorated joint damage, inhibited RORγt expression, and increased Foxp3 expression in CIA mice. DTYMT significantly decreased IL-1ß, IL-17, and TNF-α mRNA levels, and increased IL-10 mRNA levels in IL-6-induced cells. Additionally, DTYMT inhibited Th17 cell differentiation and promoted Treg cell production, thus improving the Treg/Th17 imbalance. DTYMT also inhibited the proliferation, migration, and invasion of RA fibroblast-like synovial cells. Conclusions: These results indicate that DTYMT could regulate the Treg/Th17 cell balance, which is a possible mechanism of DTYMT in treating RA.

15.
Nanomaterials (Basel) ; 13(6)2023 Mar 19.
Article in English | MEDLINE | ID: mdl-36985998

ABSTRACT

FeCoNiCrMo0.2 high entropy alloy has many excellent properties, such as high strength, high wear resistance, high corrosion resistance, and high ductility. To further improve the properties of this coating, FeCoNiCrMo high entropy alloy (HEA) coatings, and two composite coatings, FeCoNiCrMo0.2 + WC and FeCoNiCrMo0.2 + WC + CeO2, were prepared on the surface of 316L stainless steel by laser cladding technology. After adding WC ceramic powder and CeO2 rare earth control, the microstructure, hardness, wear resistance, and corrosion resistance of the three coatings were carefully studied. The results show that WC powder significantly improved the hardness of the HEA coating and reduced the friction factor. The FeCoNiCrMo0.2 + 32%WC coating showed excellent mechanical properties, but the distribution of hard phase particles in the coating microstructure was uneven, resulting in unstable distribution of hardness and wear resistance in each region of the coating. After adding 2% nano-CeO2 rare earth oxide, although the hardness and friction factor decreased slightly compared with the FeCoNiCrMo0.2 + 32%WC coating, the coating grain structure was finer, which reduced the porosity and crack sensitivity of the coating, and the phase composition of the coating did not change; there was a uniform hardness distribution, a more stable friction coefficient, and the flattest wear morphology. In addition, under the same corrosive environment, the value of polarization impedance of the FeCoNiCrMo0.2 + 32%WC + 2%CeO2 coating was greater, the corrosion rate was relatively low, and the corrosion resistance was better. Therefore, based on various indexes, the FeCoNiCrMo0.2 + 32%WC + 2%CeO2 coating has the best comprehensive performance and can extend the service life of 316L workpieces.

16.
Plant Sci ; 329: 111623, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36750140

ABSTRACT

High temperature stress is one of the primary abiotic stresses that restrict fruit tree production. Grapevine (Vitis vinifera) with high economic value throughout the world is a cultivated fruit crop, and its growth and development is often influenced by high temperature stress. Studying the heat stress-response mechanism of grapevine has great significance for understanding the acclimation to heat stress. In this study, we identified a series of heat stress responsive miRNAs and analyzed their function during the heat tolerance response. CK (control group, 25 °C) and heat treatment stress (TS, 45 °C) small RNA (sRNA) libraries were constructed and sequenced by high-throughput sequencing in 'Thompson seedless' grapevine. 873 known-miRNAs and 86 novel-miRNAs were identified, of which 88 known and three novel miRNAs were expressed differentially under heat stress. 322 genes were predicted to be targeted by the miRNAs. Eight selected miRNAs and its targets were confirmed by real time quantitative PCR (RT - qPCR), indicating that these "miRNA - target" were responsive to heat stress. In addition, most of the predicted target genes were negatively regulated by corresponding miRNAs. Gene function and pathway analyses indicated that these genes probably play crucial roles in heat stress tolerance. Vvi-miR167b transiently overexpression in grapevine leaves decreased target gene vvARF6, vvARF6-like and vvARF8 expression. The function of vvi-miR167 was verified by ectopic transformation in Arabidopsis thaliana, and the heat tolerance in transgenic lines was enhanced significantly, suggesting that the vvi-miR167 plays a positive regulatory role in grape thermostability. Comparison of miRNA expression patterns between heat treatment stress and CK can help elucidate the heat stress response and resistance mechanisms in grapes. In conclusion, these results gave us useful information to better understand the heat stress-response during domestication as well as for breeding new cultivars with heat stress resistance in fruit trees.


Subject(s)
MicroRNAs , Vitis , MicroRNAs/genetics , Gene Expression Regulation, Plant , Plant Breeding , Base Sequence , Heat-Shock Response , High-Throughput Nucleotide Sequencing/methods , Vitis/genetics
17.
BMJ Open ; 13(1): e063976, 2023 01 23.
Article in English | MEDLINE | ID: mdl-36690404

ABSTRACT

INTRODUCTION: Postoperative delirium (POD) is a common surgical complication. The incidence is 19% in neurological procedures, and advanced age is a risk factor for neurological procedures. Many studies have shown that dexmedetomidine (DEX) reduced the incidence of delirium after non-cardiac surgery in elderly patients. However, there are few studies focus on the effect of DEX on POD in elderly patients undergoing neurosurgery. METHODS AND ANALYSIS: This is a randomised, double-blinded, paralleled-group and controlled trial. Patients older than 65 years and scheduled for elective craniotomy will be randomly assigned to the DEX group and the control group. After endotracheal intubation, patients in the DEX group will be administered with continuous DEX infusion at rate of 0.4 µg/kg/hour until the surgical haemostasis. In the control group, patients will receive the identical volume of normal saline in the same setting. The primary outcome is the incidence of POD during the first 5 days. Delirium will be evaluated through a combination of three methods, including the Richmond Agitation Sedation Scale (RASS), the confusion assessment method for ICU (CAM-ICU) and the 3 min diagnostic interview for CAM (3D-CAM). The RASS, CAM-ICU and 3D-CAM will be evaluated two times per day (08:00-10:00 and 18:00-20:00 hours) during the first postoperative 5 days. Secondary outcomes include pain severity score, quality of recovery, quality of sleep, cognitive function, psychological health state, intraoperative data, physiological status, length of stay in ICU and hospital, hospitalisation costs, non-delirium complications, and 30-day all-cause mortality. ETHICS AND DISSEMINATION: The protocol (V.4.0) has been approved by the medical ethics committee of Beijing Tiantan Hospital, Capital Medical University (KY2021-194-03). The findings of the study will be disseminated in a peer-reviewed journal and at a scientific conference. TRIAL REGISTRATION NUMBER: NCT05168280.


Subject(s)
Dexmedetomidine , Emergence Delirium , Humans , Aged , Dexmedetomidine/therapeutic use , Emergence Delirium/chemically induced , Double-Blind Method , Intensive Care Units , Craniotomy , Randomized Controlled Trials as Topic
18.
Neuropsychopharmacology ; 48(6): 929-935, 2023 05.
Article in English | MEDLINE | ID: mdl-36635595

ABSTRACT

Chronic inflammation has been implicated in the pathophysiology of major depressive disorder (MDD). Activating the resolution of inflammation through ω-3 fatty acid supplementation may prove to be a successful therapeutic strategy for the treatment of MDD. Patients with MDD, body mass index >25 kg/m2, and plasma high-sensitivity C-reactive protein ≥3 µg/mL (n = 61) were enrolled in a 12-week randomized trial consisting of 4 parallel arms: EPA 1, 2, and 4 g/d, and placebo. The supplement contained EPA and DHA in a 3.9:1 ratio. Depression symptoms were assessed using the IDS-C30 scale. Plasma fatty acids and pro-resolving lipid mediators (SPMs) were measured in 42 study completers at baseline and at the end of treatment by liquid chromatography/mass spectrometry. The response rate (≥50% reduction in IDS-30 score) was higher in the 4 g/d EPA arm than placebo (Cohen d = 0.53). In the 4 g/d EPA arm, responders had significantly greater increases in 18-hydroxyeicosapentaenoic acid (18-HEPE) and 13-hydroxydocosahexaenoic acid (13-HDHA) than non-responders (p < 0.05). Within the 4 g/d EPA arm, the increase in 18-HEPE was significantly associated with reductions in plasma hs-CRP concentrations (p < 0.05) and IDS-C30 scores (p < 0.01). In summary, response rates were greater among patients with MDD randomized to EPA 4 g/d supplementation and in those who showed a greater ability to activate the synthesis of 18-HEPE. The inverse association of 18-HEPE with both systemic inflammation and symptoms of depression highlights the activation of the resolution of inflammation as a likely mechanism in the treatment of MDD with ω-3 fatty acid supplementation.


Subject(s)
Depressive Disorder, Major , Fatty Acids, Omega-3 , Humans , Depressive Disorder, Major/drug therapy , Eicosapentaenoic Acid/therapeutic use , Docosahexaenoic Acids/therapeutic use , Inflammation , Dietary Supplements , C-Reactive Protein
19.
ACS Macro Lett ; 12(1): 26-32, 2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36541821

ABSTRACT

Targeting sustainable and eco-friendly polymer synthesis, we demonstrate here a synergistically catalyzed atom transfer radical polymerization (ATRP) induced and controlled by interplay between ball milling (BM) and piezoelectric nanoparticles (piezoNPs). BM-induced electron transfer can be achieved through piezoNPs deformation under impact force, serving as an external stimulus to mediate polymerization. The ppm level of copper loading is sufficient in fabrication of a polymer with well-defined molecular weight and low polydispersity. High-molecular-weight polymers ranging from 33 to 74 kDa were prepared successfully through DMSO-assisted grinding. Besides, its good performance on availability of water as liquid-assisted grinding additive, the recyclability of piezoNPs, and the formation of cross-linker-free composite resin make our ATRP approach a green and practical option alongside the existent heat-, electro-, and photo-induced methods.

20.
Macromol Rapid Commun ; 44(3): e2200693, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36250510

ABSTRACT

Multiple and two-way reversible shape memory polymers (M/2W-SMPs) are highly promising for many fields due to large deformation, lightweight, strong recovery stress, and fast response rates. Herein, a semi-crystalline block poly(urethane-urea-amide) elastomers (PUUAs) are prepared by the copolymerization of isocyanate-terminated polyurethane (OPU) and amino-terminated oligomeric polyamide-1212 (OPA). PUUAs, composed of OPA as stationary phase and PTMEG as reversible phase, exhibit excellent rigidity, flexibility, and resilience, and cPUUA-C7 -S25 exhibits the best tensile property with strength of 10.3 MPa and elongation at break of 360.2%. Besides, all the PUUAs possess two crystallization/melting temperatures and a glass transition temperature, which endow PUUAs with multiple and reversible two-way shape memory effect (M/2W-SME). Physically crosslinked PUUA-C0 -S25 exhibits excellent dual and triple shape memory, and micro chemically crosslinked cPUUA-C7 -S25 further shows quadruple shape memory behavior. Additionally, both PUUA-C0 -S25 and cPUUA-C7 -S25 have 2W-SME. Intriguingly, cPUUA-C7 -S25 can achieve a higher temperature (up to 165 °C) SME, which makes it suitable for more complex and changeable applications. Based on the advantages of M/2W-SME, a temperature-responsive application scenario where PUUAs can transform spontaneously among different shapes is designed. These unique M/2W-SME and high-temperature SME will enable the applications of high-temperature sensors, actuators, and aerospace equipment.


Subject(s)
Elastomers , Polymers , Polymers/chemistry , Amides , Urea , Polyurethanes/chemistry
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