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1.
J Stroke Cerebrovasc Dis ; : 107769, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38750835

RESUMO

OBJECTIVE: To investigate the relationship between short-term glycemic variability in patients with T2DM and the vulnerability of intracranial atherosclerotic plaques using HR-MR-VWI. MATERIALS AND METHODS: In total, 203 patients with acute ischemic stroke (AIS)/transient ischemia (TIA) combined with T2DM were enrolled. All of them underwent HR-MR-VWI during the period between July 2020 and July 2023. 203 patients were divided into groups with higher (1,5-AG≤30.7µmol/L) and lower (1,5-AG>30.7µmol/L) short-term glycemic variability. Patients were also divided into the T1WI and non-T1WI hyperintensity groups. Associated factors(FBG, HbA1c, and 1,5-AG)for the T1WI hyperintensity were analyzed by binary logistic regression. We used the area under the curve (AUC), while the sensitivity and specificity were calculated at the optimal threshold. The Delong test was employed to compare the quality of the AUC of the predictors. RESULTS: The group with higher short-term glycemic variability had a higher incidence of the hyperintensity on T1WI, higher degree of enhancement, higher degree of stenosis and smaller lumen area (P<0.05). The T1WI hyperintensity group had higher HbA1c levels, higher hemoglobin levels and lower 1,5-AG levels(P<0.05). 1,5-AG (OR=0.971, 95% CI: 0.954∼0.988, P=0.001), HbA1c (OR=1.305, 95% CI: 1.065∼1.598, P=0.01) and male sex (OR=2.048, 95% CI: 1.016∼4.128, P=0.045)/(OR=2.102, 95% CI: 1.058∼4.177, P=0.034) were independent risk factors for the hyperintensity on T1WI. 1,5-AG demonstrated enhanced performance and yielded the highest AUC of the receiver operator characteristic curve (AUC=0.726), with sensitivity and specificity values of 0.727 and 0.635 respectively. CONCLUSION: 1,5-AG, HbA1c and male sex are independent predictors of intracranial plaques with T1WI hyperintensity, the greater short-term glycemic variability, the higher incidence of vulnerable plaques.

2.
Sci Rep ; 14(1): 9337, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653762

RESUMO

Soil water-holding capacity decreases due to long-term mineral fertilizer application. The objective of this study was to determine how replacing mineral fertilizer with maize straw affected the soil water retention curve, soil water content, soil water availability, and soil equivalent pore size. Replacement treatments in which 25% (S25), 50% (S50), 75% (S75), and 100% (S100) of 225 kg ha-1 nitrogen from mineral fertilizer (CK) was replaced with equivalent nitrogen from maize straw were conducted for five years in the Loess Plateau of China. The Gardner model was used to fit the soil water retention curve and calculate the soil water constant and equivalent pore size distribution. The results indicated that the Gardner model fitted well. Replacing nitrogen from mineral fertilizer with nitrogen from straw increased soil specific water capacity, soil readily available water, soil delayed available water, soil available water, soil capillary porosity, and soil available water porosity over time. S25 increased field capacity and wilting point from the fourth fertilization year. S50 enhanced soil readily available water, soil delayed available water, soil available water, and soil available water porosity from the fifth fertilization year, whereas S25 and S75 increased these from the third fertilization year or earlier. Soil specific water capacity, soil readily available water, soil delayed available water, soil available water, soil capillary porosity, and soil available water porosity could better reflect soil water-holding capacity and soil water supply capacity compared with field capacity and wilting point.

3.
Front Microbiol ; 15: 1343302, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357342

RESUMO

Introduction: To investigate the effects of different drip irrigation periods on soil microbial communities and functions. Methods: Increasing drip irrigation amount at the seedling (S), jointing (J), bell (B), tasseling (T) and grain filling (G) stages of maize were studied using no increase in irrigation amount as control (CK). Principal component analysis was conducted to comprehensively evaluate soil microbial quality following the different drip irrigation treatments. In addition, the characteristics of the community structure and the potential functional composition of soil bacteria and fungi were comparatively analyzed by combining amplicon sequencing and functional prediction methods. Results: The results indicated that MBNT15 was the most important genus for the classification of soil bacterial samples, Saitozyma was the most important genus for the classification of soil fungal samples, and fungi were more important than bacteria for the classification of soil microbial samples. Compared with fungal communities, bacterial communities exhibited high levels of functional diversity. The proportion of metabolism was the highest in the prediction of bacterial primary functions, and carbohydrate metabolism and amino acid metabolism were important functions in the prediction of bacterial secondary functions. BugBase phenotype prediction results showed that soil bacteria under B treatment had a higher number of aerobic bacteria and greater resistance to disease and stress. The J treatment had the highest number of bacteria with biofilm forms, and the J, S, and G treatments contained more potentially pathogenic bacteria but fewer stress-tolerant bacteria compared with the CK treatment. The number of Saprotroph was the largest and the number of Symbiotroph was the least. The relative abundances of Saprotroph, Pathotroph and Symbiotroph were 68.60%~74.33%, 15.76%~20.60% and 9.16%~11.13%, respectively. Discussion: The findings provide a reference for conserving water resources, improving maize yield, and predicting soil microbial metabolic potential and function by reflecting the richness of the soil microbial community structure in maize fields.

4.
Small ; 20(1): e2304502, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37649185

RESUMO

Reduced graphene oxide (rGO) has garnered extensive attention as electrodes, sensors, and membranes, necessitating the efficient reduction of graphene oxide (GO) for optimal performance. In this work, a swift reduction of GO that involves bringing GO foam in contact with semi-molten metals like tin (Sn) and lithium (Li) is presented. These findings reveal that the electrical resistance of GO foam is significantly diminished by its interaction with these metals, even in dry air. Taking inspiration from this technique, Sn foil is employed to encase the GO foam, followed by a calcination in 15 vol% H2 /Ar environment at 235 °C to fabricate the rGO, which demonstrates a remarkably lower electrical resistivity of 0.42 Ω cm when compared to the chemically reduced GO via hydrazine hydrate (650 Ω cm). The reduction mechanism entails the migration of Sn on GO and its subsequent reaction with oxygen functional groups. SnO/Sn(OH)2 formed from the reaction can be subsequently reversed through reduction by H2 to Sn. Utilizing this rGO as the host material for a sulfur cathode, a lithium-sulfur battery is constructed that displays a specific capacity of 1146 mAh g-1 and maintains a capacity retention of 68.4% after 300 cycles at a rate of 0.2 C.

5.
Langmuir ; 39(51): 19016-19026, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38085956

RESUMO

With excellent properties such as great flexibility, outstanding chemical resistance, and superb mechanical strength, two-part polyurethane (2K PU) adhesives have been widely applied in many applications, including those in transportation and construction. Despite the extensive use, their adhesion to nonpolar polymer substrates still needs to be improved and has been widely studied. The incorporation of silane molecules and the use of plasma treatment on substrate surfaces are two popular methods to increase the adhesion of 2K PU adhesives, but their detailed adhesion enhancement mechanisms are still largely unknown. In this research, sum frequency generation (SFG) vibrational spectroscopy was used to probe the influence of added or coated silanes on the interfacial structure at the buried polypropylene (PP)/2K PU adhesive interface in situ. How plasma treatment on PP could improve adhesion was also investigated. To achieve maximum adhesion, two methods to involve silanes were studied. In the first method, silanes were directly mixed with the 2K PU adhesive before use. In the second method, silane molecules were spin-coated onto the PP substrate before the PU adhesive applied. It was found that the first method could not improve the 2K PU adhesion to PP, while the second method could substantially enhance such adhesion. SFG studies demonstrated that with the second method silane molecules chemically reacted at the interface to connect PP and 2K PU adhesive to improve the adhesion. With the first method, silane molecules could not effectively diffuse to the interface to enhance adhesion. In this research, plasma treatment was also found to be a useful method to improve the adhesion of the 2K PU adhesive to nonpolar polymer materials.

6.
Materials (Basel) ; 16(14)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37512394

RESUMO

Copper-coated graphite and copper mixture powders were deposited on AZ31B magnesium alloy and 6061 T6 aluminum alloy substrates under different process parameters by a solid-state cold spray technique. The microstructure of the copper-coated graphite and copper composite coatings was visually examined using photographs taken with an optical microscope and a scanning electron microscope. The surface roughness of the coatings was investigated with a 3D profilometer. The thickness of the coatings was determined through the analysis of the microstructure images, while the adhesion of the coatings was characterized using the scratch test method. The results indicate that the surface roughness of the coatings sprayed on the two different substrates gradually decreases as gas temperature and gas pressure increase. Additionally, the thickness and adhesion of the coatings deposited on the two different substrates both increase with an increase in gas temperature and gas pressure. Comparing the surface roughness, thickness, and adhesion of the coatings deposited on the two different substrates, the surface roughness and adhesion of the coatings on the soft substrate are greater than those of the coatings on the hard substrate, while the thickness of the coatings is not obviously affected by the hardness of the substrate. Furthermore, it is noteworthy that the surface roughness, thickness, and adhesion of the copper-coated graphite and copper composite coatings sprayed on the two different substrates exhibit a distinct linear relationship with particle velocity.

7.
BMC Genomics ; 24(1): 354, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365511

RESUMO

BBX proteins play important roles in all of the major light-regulated developmental processes. However, no systematic analysis of BBX gene family regarding the regulation of photoperiodic microtuber formation has been previously performed in yam. In this study, a systematic analysis on the BBX gene family was conducted in three yam species, with the results, indicating that this gene plays a role in regulating photoperiodic microtuber formation. These analyses included identification the BBX gene family in three yam species, their evolutionary relationships, conserved domains, motifs, gene structure, cis-acting elements, and expressional patterns. Based on these analyses, DoBBX2/DoCOL5 and DoBBX8/DoCOL8 showing the most opposite pattern of expression during microtuber formation were selected as candidate genes for further investigation. Gene expression analysis showed DoBBX2/DoCOL5 and DoBBX8/DoCOL8 were highest expressed in leaves and exhibited photoperiod responsive expression patterns. Besides, the overexpression of DoBBX2/DoCOL5 and DoBBX8/DoCOL8 in potato accelerated tuber formation under short-day (SD) conditions, whereas only the overexpression of DoBBX8/DoCOL8 enhanced the accelerating effect of dark conditions on tuber induction. Tuber number was increased in DoBBX8/DoCOL8 overexpressing plants under dark, as well as in DoBBX2/DoCOL5 overexpressing plants under SD. Overall, the data generated in this study may form the basis of future functional characterizations of BBX genes in yam, especially regarding their regulation of microtuber formation via the photoperiodic response pathway.


Assuntos
Dioscorea , Dioscorea/genética , Dioscorea/metabolismo , Perfilação da Expressão Gênica , Família Multigênica , Fotoperíodo , Ritmo Circadiano , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
8.
Small ; 19(36): e2300286, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37162459

RESUMO

Lithium-sulfur (Li-S) battery has been considered as a strong contender for commercial aerospace battery, but the commercialization requires Ah-level pouch cells with both efficient discharge at high rates and ultra-high energy density. In this paper, the application of lithium-sulfur batteries for powering drones by using the cathode of highly dispersed sulfur nanoparticles with well-controlled particle sizes have been realized. The sulfur nanoparticles are prepared by a precipitation method in an eco-friendly and efficient way, and loaded on graphene oxide-cetyltrimethylammonium bromide by molecular grafting to realize a large-scale fabrication of sulfur-based cathodes with superior electrochemical performance. A button cell based on the cathode exhibits an excellent discharge capacity of 62.8 mAh cm-2 at a high sulfur loading of 60 mg cm-2 (i.e., 1046.7 mAh g-1 ). The assembled miniature pouch cell (PCmini) shows a discharge capacity of 130 mAh g-1 , while the formed Ah-level pouch cell (PCAh) achieves energy density of 307 Wh kg-1 at 0.3C and 92 Wh kg-1 at 4C. Especially, a four-axis propeller drone powered by the PC has successfully completed a long flight (>3 min) at high altitudes, demonstrating the practical applicability as aviation batteries.

9.
J Clin Neurosci ; 111: 1-5, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37032584

RESUMO

BACKGROUND AND OBJECTIVES: Insulin resistance (IR) plays an important role in the pathogenesis of cerebral small vessel disease (CSVD); however, little is known about the relationship between IR and the incidence of cerebral microbleeds (CMBs) in Asian populations. The aim of this study is to investigate the relationship between CMBs and IR in Chinese patients with CSVD. METHODS: This retrospective study included 240 patients with CSVD. Patients were categorized by the homeostatic model assessment of insulin resistance (HOMA-IR): Quartile 1 (≤1.26), Quartile 2 (1.27-1.92), Quartile 3 (1.93-2.89), and Quartile 4 (>2.89). The medical record of each patient was reviewed, and demographic, clinical and laboratory information was abstracted. All patients completed an MRI scan, and CMBs were defined as round or ovoid hypointense lesions on SWI sequence. RESULTS: CMBs were present in 82 (34.17%) of the 240 patients that were included in the study (mean age, 71 years; male, 54.89%). After adjustment for potential confounding variables, insulin resistance was associated with the presence of CMBs (adjusted odds ratio 2.298, 95% confidence interval 1.017-5.194 for Q4:Q1; P = 0.046). According to receiver operating characteristic analysis, the best discriminating factor for CMBs was a HOMA-IR level ≥2.215 (area under the curve 0.595; sensitivity 51.2%; specificity 65.2%). CONCLUSIONS: IR is significantly associated with the presence of CMBs, suggesting the potential role of IR as a predictive marker for CMBs in patients with CSVD.


Assuntos
Hemorragia Cerebral , Doenças de Pequenos Vasos Cerebrais , Resistência à Insulina , Idoso , Humanos , Masculino , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/complicações , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , População do Leste Asiático , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Feminino
10.
Chemistry ; 29(35): e202300366, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37051734

RESUMO

Selective and sensitive detection of inorganic pyrophosphate (PPi) are of great significance both for clinical applications and fundamental research. In this work, a ratiometric fluorescent probe was developed by decorating a porphyrin-based metal-organic framework (PCN-224) with sulfur nanodots (S-dots). The red-fluorescence of PCN-224 was significantly promoted (more than 6-fold) by S-dots through inhibiting molecular motion of porphyrin ligand, which also provided active sites for the detection of Cu2+ and PPi. Cu2+ could selectively quench the red-fluorescence of PCN-224 through coordination with porphyrin ligand, and the competition reaction between PPi and Cu2+ resulted in the decomposing of coordination and recovery of red-fluorescence. The blue-fluorescence from S-dots was deemed as effective reference, which provided a built-in correction in complex environments. Based on these photophysical properties, a ratiometric fluorescence assay was developed for the quantitative detection of Cu2+ and PPi, with a limit of detection of 0.11 and 2.66 µM, respectively. The accuracy and practical applications of assays were also demonstrated by detection in tap water and human serum samples.


Assuntos
Estruturas Metalorgânicas , Pontos Quânticos , Humanos , Estruturas Metalorgânicas/química , Difosfatos/química , Fluorescência , Ligantes , Bioensaio , Corantes Fluorescentes/química , Espectrometria de Fluorescência , Limite de Detecção , Pontos Quânticos/química
11.
Micromachines (Basel) ; 14(3)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985063

RESUMO

In this paper, we report a simple, rapid, low-cost, biocompatible, and detachable microfluidic chip fabrication method for customized designs based on Parafilm®. Here, Parafilm® works as both a bonding agent and a functional membrane. Its high ultimate tensile stress (3.94 MPa) allows the demonstration of high-performance actuators such as microvalves and micropumps. By laser ablation and the one-step bonding of multiple layers, 3D structured microfluidic chips were successfully fabricated within 2 h. The consumption time of this method (~2 h) was 12 times less than conventional photolithography (~24 h). Moreover, the shear stress of the PMMA-Parafilm®-PMMA specimens (0.24 MPa) was 2.13 times higher than that of the PDMS-PDMS specimens (0.08 MPa), and 0.56 times higher than that of the PDMS-Glass specimens (0.16 MPa), showing better stability and reliability. In this method, multiple easily accessible materials such as polymethylmethacrylate (PMMA), PVC, and glass slides were demonstrated and well-incorporated as our substrates. Practical actuation devices that required high bonding strength including microvalves and micropumps were fabricated by this method with high performance. Moreover, the biocompatibility of the Parafilm®-based microfluidic devices was validated through a seven-day E. coli cultivation. This reported fabrication scheme will provide a versatile platform for biochemical applications and point-of-care diagnostics.

12.
Polymers (Basel) ; 15(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36987196

RESUMO

In this work, KH550 (γ-aminopropyl triethoxy silane)-modified hexagonal boron nitride (BN) nanofillers were synthesized through a one-step ball-milling route. Results show that the KH550-modified BN nanofillers synthesized by one-step ball-milling (BM@KH550-BN) exhibit excellent dispersion stability and a high yield of BN nanosheets. Using BM@KH550-BN as fillers for epoxy resin, the thermal conductivity of epoxy nanocomposites increased by 195.7% at 10 wt%, compared to neat epoxy resin. Simultaneously, the storage modulus and glass transition temperature (Tg) of the BM@KH550-BN/epoxy nanocomposite at 10 wt% also increased by 35.6% and 12.4 °C, respectively. The data calculated from the dynamical mechanical analysis show that the BM@KH550-BN nanofillers have a better filler effectiveness and a higher volume fraction of constrained region. The morphology of the fracture surface of the epoxy nanocomposites indicate that the BM@KH550-BN presents a uniform distribution in the epoxy matrix even at 10 wt%. This work guides the convenient preparation of high thermally conductive BN nanofillers, presenting a great application potential in the field of thermally conductive epoxy nanocomposites, which will promote the development of electronic packaging materials.

13.
Diagnostics (Basel) ; 13(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36832291

RESUMO

(1) Background: Symptomatic intracranial artery atherosclerosis (sICAS) is an important cause of acute ischaemic stroke (AIS) and is associated with a high risk of stroke recurrence. High-resolution magnetic resonance vessel wall imaging (HR-MR-VWI) is an effective method for evaluating atherosclerotic plaque characteristics. Soluble lectin-like oxidised low-density lipoprotein receptor-1 (sLOX-1) is closely associated with plaque formation and rupture. We aim to explore the correlation between sLOX-1 levels and culprit plaque characteristics, based on HR-MR-VWI, with stroke recurrence in patients with sICAS. (2) Methods: A total of 199 patients with sICAS underwent HR-MR-VWI between June 2020 and June 2021 in our hospital. The culprit vessel and plaque characteristics were assessed according to HR-MR-VWI, and sLOX-1 levels were measured by ELISA (enzyme linked immunosorbent assay). Outpatient follow-up was performed 3, 6, 9, and 12 months after discharge. (3) Results: sLOX-1 levels were significantly higher in the recurrence group than in the non-recurrence group (p < 0.001). The culprit plaque thickness, degree of stenosis and plaque burden were higher in the recurrence group than in the non-recurrence group (p = 0.003, p = 0.014 and p = 0.010, respectively). The incidence of hyperintensity on T1WI, positive remodelling and significant enhancement (p < 0.001, p = 0.003 and p = 0.027, respectively) was higher in the recurrence group than in the non-recurrence group. Kaplan-Meier curves showed that patients with sLOX-1 levels > 912.19 pg/mL and hyperintensity on T1WI in the culprit plaque had a higher risk of stroke recurrence (both p < 0.001). Multivariate Cox regression analysis showed that sLOX-1 > 912.19 pg/mL (HR = 2.583, 95%CI 1.142, 5.846, p = 0.023) and hyperintensity on T1WI in the culprit plaque (HR = 2.632, 95% CI 1.197, 5.790, p = 0.016) were independent risk factors for stroke recurrence. sLOX-1 levels were significantly associated with the culprit plaque thickness (r = 0.162, p = 0.022), degree of stenosis (r = 0.217, p = 0.002), plaque burden (r = 0.183, p = 0.010), hyperintensity on T1WI (F = 14.501, p < 0.001), positive remodelling (F = 9.602, p < 0.001), and significant enhancement (F = 7.684, p < 0.001) (4) Conclusions: sLOX-1 levels were associated with vulnerability of the culprit plaque and can be used as a supplement to HR-MR-VWI to predict stroke recurrence.

14.
Genes (Basel) ; 14(2)2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36833202

RESUMO

Chrysanthemum morifolium Ramat. 'Huaihuang' is a traditional Chinese medicinal plant. However, a black spot disease caused by Alternaria sp., a typical necrotrophic fungus, has a serious damaging influence on the field growth, yield, and quality of the plant. 'Huaiju 2#' being bred from 'Huaihuang', shows resistance to Alternaria sp. bHLH transcription factor has been widely studied because of their functions in growth development, signal transduction, and abiotic stress. However, the function of bHLH in biotic stress has rarely been studied. To characterize the resistance genes, the CmbHLH family was surveyed in 'Huaiju 2#'. On the basis of the transcriptome database of 'Huaiju 2#' after Alternaria sp. inoculation, with the aid of the Chrysanthemum genome database, 71 CmbHLH genes were identified and divided into 17 subfamilies. Most (64.8%) of the CmbHLH proteins were rich in negatively charged amino acids. CmbHLH proteins are generally hydrophilic proteins with a high aliphatic amino acid content. Among the 71 CmbHLH proteins, five CmbHLHs were significantly upregulated by Alternaria sp. infection, and the expression of CmbHLH18 was the most significant. Furthermore, heterologous overexpression of CmbHLH18 could improve the resistance of Arabidopsis thaliana to necrotrophic fungus Alternaria brassicicola by enhancing callose deposition, preventing spores from entering leaves, reducing ROS accumulation, increasing the activities of antioxidant enzymes and defense enzymes, and promoting their gene expression levels. These results indicate that the five CmbHLHs, especially CmbHLH18, may be considered candidate genes for resistance to necrotrophic fungus. These findings not only increase our understanding of the role CmbHLHs play in biotic stress but also provide a basis by using CmbHLHs to breed a new variety of Chrysanthemum with high resistance to necrotrophic fungus.


Assuntos
Arabidopsis , Chrysanthemum , Alternaria/genética , Fatores de Transcrição/genética , Melhoramento Vegetal , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas
15.
Langmuir ; 39(9): 3273-3285, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36808974

RESUMO

One-part (1K) polyurethane (PU) adhesive has excellent bulk strength and environmental resistance. It is therefore widely used in many fields, such as construction, transportation, and flexible lamination. However, when contacting non-polar polymer materials, the poor adhesion of 1K PU adhesive may not be able to support its outdoor applications. To solve this problem, plasma treatment of the non-polar polymer surface has been utilized to improve adhesion between the polymer and 1K PU adhesive. The detailed mechanisms of adhesion enhancement of the 1K PU adhesive caused by plasma treatment on polymer substrates have not been studied extensively because adhesion is a property of buried interfaces which are difficult to probe. In this study, sum frequency generation (SFG) vibrational spectroscopy was used to investigate the buried PU/polypropylene (PP) interfaces in situ nondestructively. Fourier-transform infrared spectroscopy, the X-ray diffraction technique, and adhesion tests were used as supplemental methods to SFG in the study. The 1K PU adhesive is a moisture-curing adhesive and usually needs several days to be fully cured. Here, time-dependent SFG experiments were conducted to monitor the molecular behaviors at the buried 1K PU adhesive/PP interfaces during the curing process. It was found that the PU adhesives underwent rearrangement during the curing process with functional groups gradually becoming ordered at the interface. Stronger adhesion between the plasma-treated PP substrate and the 1K PU adhesive was observed, which was achieved by the interfacial chemical reactions and a more rigid interface. Annealing the samples increased the reaction speed and enhanced the bulk PU strength with higher crystallinity. In this research, molecular mechanisms of adhesion enhancement of the 1K PU adhesive caused by the plasma treatment on PP and by annealing the PU/PP samples were elucidated.

16.
Clin Neurol Neurosurg ; 225: 107586, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36641992

RESUMO

OBJECTIVE: Cerebral small vessel disease (CSVD) is one of the main contributing factors to vascular cognitive impairment (VCI), with an increasing incidence rate. However, the genesis of CSVD cognitive impairment remains unknown. Inflammation and metabolic disorders are considered important pathogenesis of CSVD. In addition to acting as the key regulator of aerobic glycolysis, pyruvate kinase muscle isozyme 2 (PKM2) is a proinflammatory mediator transcriptional activator that can promote an inflammatory response. This study explored whether serum PKM2 is associated with cognitive impairment in CSVD patients. METHODS: The demographic data, history of risk factors, laboratory data, and cognitive function scale assessment of 219 CSVD patients were analyzed, and the correlation between the CSVD clinical data and neuroimaging parameters with serum PKM2 was further explored. The serum PKM2 level was determined by enzyme-linked immunosorbent assay using the collected serum samples. Insulin resistance (IR) was assessed with reference to the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). HOMA-IR was calculated using the formula HOMA-IR = fasting plasma glucose (FPG, mmol/L) × fasting insulin (FINS, µU/mL)/22.5. A binomial logistic regression model was referred to infer the risk factors for VCI, and the ability of serum PKM2 to diagnose VCI was assessed by using a ROC curve. RESULTS: Serum PKM2 level was positively correlated with HOMA-IR (r = 0.206, P = 0.002), negatively correlated with MMSE and MOCA on the cognitive scale in CSVD patients, and higher in CSVD patients with white matter hyperintensities (WMH) (P < 0.001). When compared with patients without cognitive impairment, the serum PKM2 levels were elevated in cases with suspected dementia, mild dementia, mild to moderate dementia, and moderate to severe dementia, and the differences were statistically significant (P < 0.05). Serum PKM2 levels were correlated with cognitive screening test scores in CSVD. CONCLUSION: The present findings indicated that the serum PKM2 level was positively correlated with HOMA-IR, WMH, and enlarged perivascular spaces and negatively correlated with cognitive function in CSVD patients.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Demência , Resistência à Insulina , Humanos , Piruvato Quinase , Cognição , Disfunção Cognitiva/etiologia , Demência/complicações , Doenças de Pequenos Vasos Cerebrais/complicações
17.
Eur Radiol ; 33(2): 970-980, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36066731

RESUMO

OBJECTIVES: To develop a clot-based radiomics model using CT imaging radiomic features and machine learning to identify cardioembolic (CE) stroke before mechanical thrombectomy (MTB) in patients with acute ischemic stroke (AIS). MATERIALS AND METHODS: This retrospective four-center study consecutively included 403 patients with AIS who sequentially underwent CT and MTB between April 2016 and July 2021. These were grouped into training, testing, and external validation cohorts. Thrombus-extracted radiomic features and basic information were gathered to construct a machine learning model to predict CE stroke. The radiological characteristics and basic information were used to build a routine radiological model. A combined radiomics and radiological features model was also developed. The performances of all models were evaluated and compared in the validation cohort. A histological analysis helped further assess the proposed model in all patients. RESULTS: The radiomics model yielded an area under the curve (AUC) of 0.838 (95% confidence interval [CI], 0.771-0.891) for predicting CE stroke in the validation cohort, significantly higher than the radiological model (AUC, 0.713; 95% CI, 0.636-0.781; p = 0.007) but similar to the combined model (AUC, 0.855; 95% CI, 0.791-0.906; p = 0.14). The thrombus radiomic features achieved stronger correlations with red blood cells (|rmax|, 0.74 vs. 0.32) and fibrin and platelet (|rmax|, 0.68 vs. 0.18) than radiological characteristics. CONCLUSION: The proposed CT-based radiomics model could reliably predict CE stroke in AIS, performing better than the routine radiological method. KEY POINTS: • Admission CT imaging could offer valuable information to identify the acute ischemic stroke source by radiomics analysis. • The proposed CT imaging-based radiomics model yielded a higher area under the curve (0.838) than the routine radiological method (0.713; p = 0.007). • Several radiomic features showed significantly stronger correlations with two main thrombus constituents (red blood cells, |rmax|, 0.74; fibrin and platelet, |rmax|, 0.68) than routine radiological characteristics.


Assuntos
AVC Embólico , AVC Isquêmico , Trombose , Humanos , AVC Isquêmico/diagnóstico por imagem , Estudos Retrospectivos , Trombose/complicações , Trombose/diagnóstico por imagem , Fibrina , Tomografia Computadorizada por Raios X
19.
J Stroke Cerebrovasc Dis ; 31(9): 106624, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35933933

RESUMO

AIM: In the current study we aim the identification of the culprit plaque characteristics of intracranial arteries using high-resolution magnetic resonance vessel wall imaging (HR-MR-VWI). Moreover, we target the evaluation of the predictive value of culprit plaque characteristics for short-term stroke recurrence combined with ESRS. MATERIALS AND METHODS: We conducted a prospective cohort study on 342 patients diagnosed with symptomatic intracranial atherosclerotic stenosis (sICAS), out of which 243 were men and 99 were women with an average age of 64 ± 12 years. 184 cases of anterior circulation ischemia (ACIS) and 158 cases of posterior circulation ischemia (PCIS) were included in the study. All of them underwent HR-MR-VWI during the period between February 2020 and June 2021 in the Second Affiliated Hospital of Nantong University, Nantong, China. The culprit vessel and culprit plaque characteristics were assessed based on HR-MR-VWI images, and the patients' ESRS were obtained from the electronic medical records of the hospital. Concerning the obtained results from the 6-month follow-up, the patients were divided into the non-recurrence group and the recurrence group, and the differences in the above-mentioned features between the two groups were compared. The univariate Cox regression analysis combined with ESRS was performed to screen out the independent risk factors associated with recurrent stroke with P < 0.1. Receiver operating characteristic curves (ROC curves) were plotted to analyze the predictive performance of the culprit plaque characteristics, ESRS and combined variables for stroke recurrence. We used the area under the curve (AUC) ROC, while the sensitivity and specificity were calculated at the optimal threshold. The Delong test was employed to compare the quality of the AUC of the predictors. RESULTS: A total of 15.5% (53/342) of patients had a stroke recurrence within six months, with statistically significant differences (P < 0.05) between the two groups regarding the ESRS, medical history of diabetes mellitus, myocardial infarction, data for previous acute ischemic stroke (AIS) or transient ischemic attack(TIA), history of peripheral vascular disease, and serum brain natriuretic peptide level. In the patients with ACIS, the incidence of hyperintensity on the T1-weighted imaging (T1WI) was significantly different between the recurrence and the non-recurrence groups (P < 0.05). In the patients with PCIS, statistically significant differences between the recurrence and the non-recurrence group were detected in the culprit plaque burden, degree of enhancement, and incidence of hyperintensity on T1WI (P < 0.05). The ESRS (hazard ratios [HR], 1.598, 95% confidence interval [CI], 1.193-2.141, P = 0.002) ,degree of enhancement (HR = 1.764, 95% CI 0.985-3.087, P = 0.047) and hyperintensity on T1WI (HR = 2.745, 95% CI 1.373-5.488, P = 0.004) proved to be independent risk factors for stroke recurrence. The ESRS predicted stroke recurrence with AUC = 0.618 (95% CI 0.564-0.670), while the best cut-off value was 2 points. Furthermore, the registered sensitivity and specificity were 60.4% and 58.5%, respectively. Regarding the degree of enhancement in the culprit plaque, the prediction of stroke recurrence was with AUC = 0.628 (95% CI 0.574-0.679) as well as with sensitivities and specificities of 58.5% and 64.4%, respectively. Regarding the hyperintensity on T1WI in culprit plaque, the prediction of stroke recurrence was with AUC = 0.678 (95% CI 0.626-0.727) as well as with sensitivities and specificities of 66.0% and 70.0%, respectively. The ESRS combined with the degree of enhancement predicted stroke recurrence with an AUC = 0.685 (95CI% 0.633-0.734), while the recorded sensitivity and specificity were 56.6% and 73.4%, respectively. The ESRS combined with hyperintensity on the T1WI predicted stroke recurrence with an AUC = 0.745 (95CI% 0.696-0.791). The recorded sensitivity and specificity were 64.2% and 76.8%, respectively. The AUC quality of the ESRS combined with hyperintensity on T1WI was higher than that of other indices (P < 0.05). CONCLUSIONS: The hyperintensity on T1WI of the culprit plaque in intracranial arteries combined with ESRS demonstrated better predictive ability for short-term stroke recurrence. We consider this of high importance for clinical application since it provides an easier way of obtaining data for precise diagnosis.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Placa Aterosclerótica , Acidente Vascular Cerebral , Idoso , Feminino , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Placa Amiloide/complicações , Placa Aterosclerótica/complicações , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/etiologia
20.
J Stroke Cerebrovasc Dis ; 31(10): 106634, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35963212

RESUMO

OBJECTIVE: To investigate the correlation between annular plaque calcification in the carotid sinus and perioperative hemodynamic disorder (HD) in carotid angioplasty and stenting (CAS). METHODS: The clinical data of 49 patients undergoing CAS due to narrowing of the carotid sinus were retrospectively analyzed. All patients had preoperative carotid computed tomography angiography (CTA) and were divided into HD and non-HD groups based on the occurrence of HD in the perioperative period of CAS. HD was defined as persistent bradycardia (heart rate < 60 beats per min) or persistent hypotension (systolic blood pressure < 90 mmHg) in the perioperative period and lasting for at least 1 h. The baseline data, including the degree of carotid artery stenosis, plaque length, plaque thickness, calcified plaque morphologies (i.e., plaque circumferential angle: < 90° defined as dotted calcification; 90°-180° defined as arcuate calcification; > 180° defined as annular calcification), contralateral carotid artery conditions, balloon diameter, and stent types, were compared between the two groups. Binary logistic regression was used to analyze the risk factors for the occurrence of HD. RESULTS: Among the 49 patients undergoing CAS, 14 (28.57%) developed perioperative HD, and 35 did not. Annular calcification was more common in the patients in the HD group than in the non-HD group. No significant differences in the probabilities of dotted and arcuate calcifications were found between the two groups (p > 0.05). The duration of continuous dopamine consumption in the HD group was 9-71 h. The average hospital stay of the HD group (10.14 ± 4.17 days) was significantly longer than that of the non-HD group (6.57 ± 1.9 days; p < 0.001). Patients in the HD group had significantly more pronounced lumen stenosis (p = 0.033) and longer plaque length (p = 0.034) than those in the non-HD group. After adjusting for age and sex, multivariate regression analysis showed that the presence of annular plaque calcification was an independent predictor of HD (odds ratio: 7.68, 95% confidence interval: 1.46-40.37, p = 0.016). CONCLUSIONS: The occurrence of annular plaque calcification in the carotid sinus was an independent risk factor for perioperative HD in CAS. Preoperative carotid CTA assists with the early identification of high-risk patients who may develop HD.


Assuntos
Angioplastia com Balão , Calcinose , Estenose das Carótidas , Placa Aterosclerótica , Angioplastia/efeitos adversos , Angioplastia com Balão/efeitos adversos , Calcinose/etiologia , Seio Carotídeo , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/terapia , Dopamina , Hemodinâmica , Humanos , Placa Aterosclerótica/etiologia , Estudos Retrospectivos , Fatores de Risco , Stents/efeitos adversos , Resultado do Tratamento
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