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Azobenzene (Azo) liquid-crystalline polymers are intriguing due to their unique photo-induced isomerization and supramolecular chirality. However, clarification on multicomponent chiral induction towards Azo polymers remains ambiguous and challenging. Herein, chiral solvents and amines were employed to control the chiroptical activity of achiral Azo polymers. Methyl L-/D-lactate was added as the poor solvent and chiral inducer to achieve the first chiral induction in Azo aggregates. Chiral amines were utilized for the second chiral induction based on the acid-base interactions between the carboxyl groups of polymers and amines. The chiral enhancement and inversion of Azo units could be observed through the synergistic or antagonistic effect between solvents and amines. The impacts of solvent, chemical structures, feed ratio, enantiomeric excess, and temperature on supramolecular chirality were systematically studied. Furthermore, this system displayed the chiroptical switching property and chiral recovery under reversible irradiation.
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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.
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Elastómeros , Polímeros , Polímeros/química , Amidas , Urea , Poliuretanos/químicaRESUMEN
Photoinduced atom transfer radical polymerization (ATRP) has been proved to be a versatile technique for polymer network formation. However, the slow polymerization rates of typical ATRP limited its application in the field of additive manufacturing (3D printing). In this work, we introduced carbon quantum dots (CQDs) for the first time to the ATRP in aqueous media and developed an ultrafast visible-light-induced polymerization system. After optimization, the polymerization could achieve a high monomer conversion (>90%) within 1 min, and the polydispersity index (PDI) of the polymer was lower than 1.25. This system was then applied as the first example of ATRP for the 3D printing of hydrogel through digital light processing (DLP), and the printed object exhibited good dimensional accuracy. Additionally, the excellent and stable optical properties of CQDs also provided interesting photoluminescence capabilities to the printed objects. We deduce this ATRP mediated 3D printing process would provide a new platform for the preparation of functional and stimuli-responsive hydrogel materials.
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A colloidal nanocrystal cluster (CNC) is a hierarchical nanostructure formed by clustering several nanocrystals into one nano-ensemble, which may exhibit unique optical or catalytic properties different from individual nanocrystals owing to the mutual interactions among neighboring component nanocrystals. However, there is still no universal synthetic route that could be applicable to diverse material compositions with precisely controlled hierarchical structures (i.e., nanocrystal number density, component nanocrystal size, and overall diameter of the CNC) up to now. Herein, a general and novel synthetic strategy was reported for crafting a wide range of inorganic CNCs (i.e., noble metal, semiconductor, and metal oxide) via utilizing amphiphilic star-like poly(4-vinylpyridine)-block-polystyrene diblock copolymers as nanoreactors prepared by sequential atom transfer radical polymerization. The hierarchical structure of rationally designed CNCs could be readily tailored by varying the P4VP molecular weight of star-like nanoreactors and the parameter optimization during the CNC preparation process, which was inaccessible by conventional synthetic methods.
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We reported the synthesis of a well-defined hollow polymer nanoparticle derived from star-shaped unimolecular micelles. ß-Cyclodextrin was first applied as an efficient macroinitiator to prepare a star-shaped PCL via ring-opening polymerization (ROP). Then, the star-shaped PCL was modified to be a macro-RAFT agent for photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization of S-Cl monomers. The prepared unimolecular micelles can be photocross-linked under UV irradiation after a simple nucleophilic substitution reaction, which made -Cl groups to be -N3 groups. After the selective removal of the PCL core, hollow polymer nanoparticles were achieved and exhibited to be a general nanoreactor strategy for the fabrication of nanocrystals with well-controlled architectures. Compared with unimolecular micelle templates, the nanocrystals prepared by hollow templates are absolutely pure as no polymer chains are embedded in the inorganic nanocrystals. In addition, by changing the concentration of the precursor, the structure of the nanocrystal can be changed from a normal spherical structure to a hollow structure.
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BACKGROUND The aim of this study was to evaluate the prevalence of inflammation and bone destruction of hand joints in rhupus patients through ultrasound examination. MATERIAL AND METHODS Ten rhupus patients and 33 systemic lupus erythematosus (SLE) patients with hand arthropathy were recruited in this single-center study, and the clinical features and ultrasound manifestations of these patients were analyzed. RESULTS We discovered that rhupus patients were older (47.31±4.35 years vs. 38.58±2.50 years, P=0.040), had longer duration of disease (median 72 months vs. median 12 months, P=0.040), had a higher positive rate (70% vs. 10.71%, P<0.001), and had higher titers of anti-CCP antibody (42.633±14.520 vs. 2.121±0.970, P<0.001) than SLE patients with arthropathy. More importantly, the prevalence rates of synovial hyperplasia (90% vs. 42.42%, P=0.008), synovitis (90% vs. 18.18%, P<0.001), synovial hyperplasia (70% vs. 10.71%, P<0.001), and bone destruction (70% vs. 6.06%, P<0.001) were higher in rhupus patients than in SLE patients with arthropathy. CONCLUSIONS Rhupus patients are more prone to develop synovitis, synovial hyperplasia, and bone destruction. Therefore, more attention should be paid to protection of the joints in rhupus patients.
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Artritis Reumatoide/diagnóstico por imagen , Articulaciones de la Mano/diagnóstico por imagen , Inflamación/diagnóstico por imagen , Lupus Eritematoso Sistémico/diagnóstico por imagen , Articulación de la Muñeca/diagnóstico por imagen , Adulto , Artritis Reumatoide/patología , Femenino , Articulaciones de la Mano/patología , Humanos , Inflamación/patología , Lupus Eritematoso Sistémico/patología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Ultrasonografía Doppler , Articulación de la Muñeca/patologíaRESUMEN
BACKGROUND To use a gout-specific quality of life (QoL) tool, the Gout Impact Scale (GIS), to evaluate characteristics of gout affecting QoL in subjects with gout. MATERIAL AND METHODS In this cross-sectional study, 169 individuals with gout completed the 24-item GIS and a general questionnaire regarding gout characteristics. The reliability and validity of the GIS were verified by Cronbach's a and exploratory factor analysis, respectively. The impact of gout characteristics on the QoL of subjects with gout was assessed by stepwise multiple regression analysis. RESULTS The 169 subjects with gout included 149 (88.2%) men and 20 (11.8%) women, of median age 43 years. The reliability of the GIS was appropriate (0.84-0.90), except for Gout Medication Side Effects (0.69) and Unmet Gout Treatment Need (0.59). Exploratory factor analysis showed that construct validity was acceptable, with a cumulative variance contribution rate of 5 common factors of 70.09% and factor loading >0.5 between each pair of items of the GIS. Univariate analysis showed that male sex was positively correlated with Well-being During Attack (p<0.05), and that source of medical expenses, current cigarette use and drinking were significantly correlated with Unmet Gout Treatment Need (p<0.05 each). A family history of gout, gout flares, and attack frequency were significantly correlated with total GIS, Well-being During Attack, and Gout Concern during Attack (p<0.05 each). Multivariate analysis suggested that history of gouty arthritis, acute attack and attack frequency had a considerable impact on QoL (p<0.05 each). CONCLUSIONS The GIS showed acceptable reliability and validity in identifying associations between poor QoL and gout characteristics.
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Pueblo Asiatico , Gota , Calidad de Vida , Encuestas y Cuestionarios , Adulto , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The modification of semiconductor nanostructures with metallic nanocomponents can promote the separation of electron/hole from photoexited semiconductors by forming heterojunctions, thus exhibit enhanced photocatalytic activities and potential applications. In this study, Pt-based NPs, including Pt, PtCu, and PtCuCo are employed as model co-catalysts to comparatively study their capability to enhance the photocatalytic activity of TiO2 nanosheets. It was found that each of Pt, PtCu, and PtCuCo can greatly enhance the photocatalytic activity of TiO2 toward degradation of organic dyes. Using electron spin resonance spectroscopy, we demonstrated that deposition of Pt-based NPs resulted in more production of reactive oxygen species including hydroxyl radicals, superoxide, and singlet oxygen. The enhancing effects of Pt-based NPs on generation of ROS and photocatalytic activity showed same trend: PtCuCo > PtCu > Pt. The mechanism underlying the enhancement differences in Pt-based NPs may be mainly related to electronic structure change of Pt in alloying with Cu and Co. These results are valuable for designing hybrid nanomaterials with high photocatalytic efficiency for applications in water purification and antibacterial products.
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Cobalto/química , Colorantes/análisis , Cobre/química , Nanopartículas del Metal/química , Platino (Metal)/química , Especies Reactivas de Oxígeno/análisis , Contaminantes Químicos del Agua/análisis , Catálisis , Fotólisis , Semiconductores , Titanio/químicaRESUMEN
Objective: To explore the role of leonurine in the regulation of synovial inflammation and joint destruction inRA. Methods: Fibroblast-like synoviocytes were isolated from synovial tissue from RA patients. Pro-inflammatory cytokine and MMP expression was evaluated using real-time PCR and a cytometric bead array. Cell migration and invasion in vitro were measured using the Boyden chamber method and the scratch assay, respectively. Protein expression was measured by western blotting. Nuclear factor kappa B (NF-κB) nuclear translocation was detected by immunofluorescence. The in vivo effect of leonurine was evaluated in mice with CIA. Results: Leonurine treatment significantly decreased the production of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8 and TNFα) and MMPs (MMP-1 and MMP-3) and suppressed the migration and invasion of RA fibroblast-like synoviocytes. The molecular analysis revealed that leonurine impaired TNFα-induced NF-κB signalling by inhibiting the phosphorylation and degradation of inhibitor of NF-κB alpha (IκBα) and subsequently preventing the nuclear translocation of the NF-κB p65 subunit. Leonurine also inhibited the p38 and Jun N-terminal kinase mitogen-activated protein kinases signalling pathways without affecting ERK signalling. Intraperitoneal injection of leonurine reduced synovial inflammation, joint destruction and the serum IL-1ß, IL-6 and TNFα levels in mice with CIA. Conclusion: Our findings show that leonurine reduces synovial inflammation and joint destruction in RA through the NF-κB and mitogen-activated protein kinases pathways. Leonurine has potential as a therapeutic agent for RA.
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Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Ácido Gálico/análogos & derivados , Adulto , Animales , Artritis Experimental/inducido químicamente , Artritis Experimental/metabolismo , Artritis Reumatoide/metabolismo , Citocinas/efectos de los fármacos , Femenino , Fibroblastos/metabolismo , Ácido Gálico/farmacocinética , Humanos , Mediadores de Inflamación/metabolismo , Masculino , Metaloproteinasa 1 de la Matriz/efectos de los fármacos , Metaloproteinasa 3 de la Matriz/efectos de los fármacos , Ratones , Persona de Mediana Edad , Proteínas Quinasas Activadas por Mitógenos/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Membrana Sinovial/efectos de los fármacos , Sinoviocitos/efectos de los fármacos , Sinoviocitos/patología , Factor de Transcripción ReIA/efectos de los fármacosRESUMEN
INTRODUCTION: It is unclear how tranexamic acid (TXA) affects blood loss and seizures in meningioma resections. We performed a systematic review and meta-analysis and tried to evaluate the effectiveness and safety of TXA use for patients undergoing meningioma resections. METHODS: Regards to this systematic review and meta-analysis (registered with CRD42023416693), we searched PubMed, Embase (Ovid), EBSCO, and Cochrane central library up to and including Oct 2023. Patients undergoing meningioma resections treated with TXA and placebo or no treatment were eligible for this study. This would allow delineation of the impact of TXA on blood loss, postoperative seizure, and other complication incidences. RESULTS: Four prospective cohort studies with 781 patients (390 patients in the TXA group and 391 patients in the control group) were conducted via a systematic review and meta-analysis. The results suggested that the application of TXA for patients undergoing meningioma resections reduced mean blood loss of 252 mL with 95% confidence interval (CI) -469.26 to -34.67 (P = 0.02) and I2 of 94% but did not increase postoperative seizure (risk ratio: 1.08; 95%CI: 0.54 to 2.15; P = 0.84) and other complication rates. CONCLUSIONS: This systematic review and meta-analysis suggests that the administration of TXA could reduce blood loss in patients undergoing intracerebral meningioma resection. REGISTRY INFORMATION: The systematic review protocol has been registered at PROSPERO (Registration No. CRD42023416693) on April 23, 2023.
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Pérdida de Sangre Quirúrgica , Meningioma , Convulsiones , Ácido Tranexámico , Humanos , Meningioma/cirugía , Ácido Tranexámico/uso terapéutico , Ácido Tranexámico/efectos adversos , Convulsiones/tratamiento farmacológico , Convulsiones/prevención & control , Pérdida de Sangre Quirúrgica/prevención & control , Antifibrinolíticos/uso terapéutico , Antifibrinolíticos/efectos adversos , Neoplasias Meníngeas/cirugía , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Resultado del TratamientoRESUMEN
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.
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Hipotensión , Infarto del Miocardio , Hemorragia Subaracnoidea , Humanos , Femenino , Anciano , Presión Sanguínea , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/cirugía , Estudios Retrospectivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Hipotensión/epidemiología , Complicaciones Intraoperatorias/epidemiologíaRESUMEN
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.
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Antifibrinolíticos , Neoplasias Meníngeas , Meningioma , Ácido Tranexámico , Humanos , Antifibrinolíticos/efectos adversos , Pérdida de Sangre Quirúrgica/prevención & control , Método Doble Ciego , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/tratamiento farmacológico , Meningioma/cirugía , Solución Salina , Convulsiones/inducido químicamente , Convulsiones/epidemiología , Ácido Tranexámico/efectos adversosRESUMEN
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.
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Artritis Experimental , Artritis Reumatoide , Digitoxigenina/análogos & derivados , Sinoviocitos , Humanos , Animales , Inflamación/metabolismo , Proliferación Celular , Fibroblastos , Membrana Sinovial/patología , Células Cultivadas , Janus Quinasa 2/metabolismo , Factor de Transcripción STAT3/metabolismoRESUMEN
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.
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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 (â¼10 mcg phylloquinone/d)-supplementation (â¼500 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.
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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.
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Dexmedetomidina , Delirio del Despertar , Humanos , Craneotomía/efectos adversos , Dexmedetomidina/uso terapéutico , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , VigiliaRESUMEN
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.
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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.
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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.
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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.