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1.
J Stroke Cerebrovasc Dis ; 33(7): 107738, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38701940

RESUMEN

OBJECTIVES: Edaravone dexborneol is neuroprotective against ischemic stroke, with free radical-scavenging and anti-inflammatory effects, but its effects in hemorrhagic stroke remain unclear. We evaluated whether edaravone dexborneol has a neuroprotective effect in intracerebral hemorrhage, and its underlying mechanisms. MATERIALS AND METHODS: Bioinformatics were used to predict the pathway of action of edaravone dexborneol. An intracerebral hemorrhage model was established using type IV collagenase in edaravone dexborneol, intracerebral hemorrhage, Sham, adeno-associated virus + edaravone dexborneol, and adeno-associated virus + intracerebral hemorrhage groups. The modified Neurological Severity Score was used to evaluate neurological function in rats. Brain water content was measured using the dry-wet weight method. Tumor necrosis factor-α, interleukin-1ß, inducible nitric oxide synthase, and γ-aminobutyric acid levels were determined by enzyme-linked immunosorbent assay. The expression levels of neurofilament light chain and γ-aminobutyric acid transaminase were determined by western blot. Nissl staining was used to examine neuronal morphology. Cognitive behavior was evaluated using a small-animal treadmill. RESULTS: Edaravone dexborneol alleviated neurological defects, improved cognitive function, and reduced cerebral edema, neuronal degeneration, and necrosis in rats with cerebral hemorrhage. The expression levels of neurofilament light chain, tumor necrosis factor-α, interleukin-1ß, inducible nitric oxide synthase, and γ-aminobutyric acid were decreased, while γ-aminobutyric acid transaminase expression was up-regulated. CONCLUSIONS: Edaravone dexborneol regulates γ-aminobutyric acid content by acting on the γ-aminobutyric acid transaminase signaling pathway, thus alleviating oxidative stress, neuroinflammation, neuronal degeneration, and death caused by excitatory toxic injury of neurons after intracerebral hemorrhage.

2.
Orphanet J Rare Dis ; 19(1): 141, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561822

RESUMEN

BACKGROUND: Klippel-Feil syndrome (KFS) is a rare congenital disorder characterized by the fusion of two or more cervical vertebrae during early prenatal development. This fusion results from a failure of segmentation during the first trimester. Although six genes have previously been associated with KFS, they account for only a small proportion of cases. Among the distinct subtypes of KFS, "sandwich fusion" involving concurrent fusion of C0-1 and C2-3 vertebrae is particularly noteworthy due to its heightened risk for atlantoaxial dislocation. In this study, we aimed to investigate novel candidate mutations in patients with "sandwich fusion." METHODS: We collected and analyzed clinical data from 21 patients diagnosed with "sandwich fusion." Whole-exome sequencing (WES) was performed, followed by rigorous bioinformatics analyses. Our focus was on the six known KFS-related genes (GDF3, GDF6, MEOX1, PAX1, RIPPLY2, and MYO18). Suspicious mutations were subsequently validated through in vitro experiments. RESULTS: Our investigation revealed two novel exonic mutations in the FGFR2 gene, which had not previously been associated with KFS. Notably, the c.1750A > G variant in Exon 13 of FGFR2 was situated within the tyrosine kinase domain of the protein, in close proximity to several established post-translational modification sites. In vitro experiments demonstrated that this certain mutation significantly impacted the function of FGFR2. Furthermore, we identified four heterozygous candidate variants in two genes (PAX1 and MYO18B) in two patients, with three of these variants predicted to have potential clinical significance directly linked to KFS. CONCLUSIONS: This study encompassed the largest cohort of patients with the unique "sandwich fusion" subtype of KFS and employed WES to explore candidate mutations associated with this condition. Our findings unveiled novel variants in PAX1, MYO18B, and FGFR2 as potential risk mutations specific to this subtype of KFS.


Asunto(s)
Síndrome de Klippel-Feil , Humanos , Síndrome de Klippel-Feil/genética , Síndrome de Klippel-Feil/complicaciones , Síndrome de Klippel-Feil/diagnóstico , Secuenciación del Exoma , Mutación/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética
3.
Molecules ; 29(8)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38675557

RESUMEN

The design and synthesis of organic photocatalysts remain a great challenge due to their strict structural constraints. However, this could be mitigated by achieving structural flexibility by constructing permanent porosity into the materials. Conjugated microporous polymers (CMPs) are an emerging class of porous materials with an amorphous, three-dimensional network structure, which makes it possible to integrate the elaborate functional groups to enhance photocatalytic performance. Here, we report the synthesis of a novel CMP, named TAPFc-TFPPy-CMP, constructed by 1,1'3,3'-tetra(4-aminophenyl)ferrocene (TAPFc) and 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) monomers. The integration of the p-type dopant 7,7,8,8-tetracyanoquinodimethane (TCNQ) into the TAPFc-TFPPy-CMP improved the light adsorption performance, leading to a decrease in the optical bandgap from 2.00 to 1.43 eV. The doped CMP (TCNQ@TAPFc-TFPPy-CMP) exhibited promising catalytic activity in photocatalytic CO2 reduction under visible light, yielding 546.8 µmol g-1 h-1 of CO with a selectivity of 96% and 5.2 µmol g-1 h-1 of CH4. This represented an 80% increase in the CO yield compared to the maternal TAPFc-TFPPy-CMP. The steady-state photoluminescence (PL) and fluorescence lifetime (FL) measurements reveal faster carrier separation and transport after the doping. This study provides guidance for the development of organic photocatalysts for the utilization of renewable energy.

5.
Zhongguo Zhong Yao Za Zhi ; 49(1): 110-122, 2024 Jan.
Artículo en Chino | MEDLINE | ID: mdl-38403344

RESUMEN

Studying the physicochemical properties and biological activities of Lycium barbarum polysaccharides(LBPs) is of great significance. The previous study had extracted LBPs(LBP-1, LBP-2, LBP-3, LBP-4, and LBP-5) by five different methods(cold water extraction, boiling water reflux extraction of the residue after cold water extraction, ultrasonic extraction with 50% ethanol, ultrasonic extraction with 25% ethanol of the residue after 50% ethanol extraction, and hot water extraction). In this study, the structures of the obtained five LBPs were characterized by UV spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Furthermore, the antioxidant, blood lipid-lowering, nitrosation-inhibting, acetylcholinesterase-inhibiting, and tyrosinase-inhibiting activities of the five LBPs were measured in vitro. The results showed that high-temperature extraction destroyed the polysaccharide structure, while ultrasound-assisted extraction ensured the structural integrity. The thermal stability and degradation behaviors differed among the five LBPs. However, the UV spectroscopic results of the five LBPs did not show significant differences, and all of the five LBPs showed the characteristic absorption peaks of proteins. LBP-3 and LBP-4 exhibited strong antioxidant activity, while LBP-3 had the strongest blood lipid-lowering activity. In addition, LBP-3 outperformed other LBPs in inhibiting nitrosation and acetylcholineste-rase, and LBP-2 showed the strongest inhibitory effect on tyrosinase. This study explored the effects of different extraction methods on the physicochemical properties and biological activities of LBPs, with a view to providing a basis for the selection of suitable extraction methods to obtain LBPs with ideal biological activities.


Asunto(s)
Medicamentos Herbarios Chinos , Lycium , Lycium/química , Monofenol Monooxigenasa , Acetilcolinesterasa , Antioxidantes/farmacología , Antioxidantes/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Polisacáridos/farmacología , Polisacáridos/química , Lípidos , Etanol , Agua
6.
Liver Int ; 44(4): 979-995, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38293784

RESUMEN

BACKGROUND & AIMS: Accumulating evidences suggest tumour microenvironment (TME) profoundly influence clinical outcome in hepatocellular carcinoma (HCC). Existing immune subtypes are susceptible to batch effects, and integrative analysis of bulk and single-cell transcriptome is helpful to recognize immune subtypes and TME in HCC. METHODS: Based on the relative expression ordering (REO) of 1259 immune-related genes, an immuno-prognostic signature was developed and validated in 907 HCC samples from five bulk transcriptomic cohorts, including 72 in-house samples. The machine learning models based on subtype-specific gene pairs with stable REOs were constructed to jointly predict immuno-prognostic subtypes in single-cell RNA-seq data and validated in another single-cell data. Then, cancer characteristics, immune landscape, underlying mechanism and therapeutic benefits between subtypes were analysed. RESULTS: An immune-related signature with 29 gene pairs stratified HCC samples individually into two risk subgroups (C1 and C2), which was an independent prognostic factor for overall survival. The machine learning models verified the immune subtypes from five bulk cohorts to two single-cell transcriptomic data. Integrative analysis revealed that C1 had poorer outcomes, higher CNV burden and malignant scores, higher sensitivity to sorafenib, and exhibited an immunosuppressive phenotype with more regulators, e.g., myeloid-derived suppressor cells (MDSCs), Mø_SPP1, while C2 was characterized with better outcomes, higher metabolism, more benefit from immunotherapy, and displayed active immune with more effectors, e.g., tumour infiltrating lymphocyte and dendritic cell. Moreover, both two single-cell data revealed the crosstalk of SPP1-related L-R pairs between cancer and immune cells, especially SPP1-CD44, might lead to immunosuppression in C1. CONCLUSIONS: The REO-based immuno-prognostic subtypes were conducive to individualized prognosis prediction and treatment options for HCC. This study paved the way for understanding TME heterogeneity between immuno-prognostic subtypes of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Transcriptoma , Microambiente Tumoral/genética , Neoplasias Hepáticas/genética , Pronóstico
7.
Heliyon ; 10(1): e23435, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38148803

RESUMEN

Background: Difficult airway remains a great challenge in patients with atlantoaxial dislocation (AAD). Preoperative evaluation and reliable prediction are required to facilitate the airway management. We aimed to screen out reliable radiological indicators for prediction of difficult laryngoscopy in patients with AAD. Methods: A retrospective nested case-control study within a single center longitudinal AAD cohort was conducted to investigate the radiological indicators. All the patients with difficult laryngoscopy from 2010 to 2021 were enrolled as the difficult laryngoscopy group. Others in the cohort without difficult laryngoscopy were randomly selected as the non-difficult laryngoscopy group by individually matching with the same gender, same surgery year, and similar age (±5 years) at a ratio of 6:1. Radiological data on preoperative lateral X-ray images between the two groups were compared. Bivariate logistic regression model was applied to screen out the independent predictive indicators and calculate the odds ratios of indicators associated with difficult laryngoscopy. Receiver operating characteristic curve and area under the curve (AUC) were used to describe the discrimination ability of indicators. Results: A total of 154 patients were finally analyzed in this study. Twenty-two patients with difficult laryngoscopy and matched with 132 controls. Four radiological parameters showed significant difference between the two groups. Among which, ΔC1C2D (the difference of the distance between atlas and axis in the neutral and extension position), owned the largest AUC. Conclusions: ΔC1C2D could be a valuable radiologic predictor for difficult laryngoscopy in patients with AAD.

8.
Int J Biol Macromol ; 258(Pt 2): 129058, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38161008

RESUMEN

High-value utilization of agricultural wastes such as rose petals promotes the development of the dual carbon economy. In this study, rose petals were pretreated by microwave-assisted deep eutectic solvent (DES). Choline chloride-ethylene glycol (ChCl-EG) was used as the basis for the addition of P-toluenesulfonic acid (TsOH) or Ferric chloride (FeCl3). Forming ternary DESs, as well as designing quaternary DESs with a synergistic effect. The effects of different types of multicomponent DES on treating anthocyanins, cellulose, and lignin in rose flowers were explored. The results showed that the highest anthocyanin extraction of 173.71 mg/g and the highest lignin removal of 40.80 % could be achieved after tetrad DES pretreatment when the molar ratio was ChCl:EG:TsOH:FeCl3 = 1:2:0.3:0.3. The interaction energy between anthocyanins and DES was calculated using density functional theory (DFT), and the maximum was -543.14 kcal/mol. This study demonstrated that DES pretreatment can provide novel insights for the utilization of roses in high-value.


Asunto(s)
Celulosa , Cloruros , Compuestos Férricos , Lignina , Antocianinas , Disolventes Eutécticos Profundos , Solventes , Microondas
9.
Materials (Basel) ; 16(22)2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-38005150

RESUMEN

Permanent deformation, or rutting, is one of several critical distresses in flexible pavements. This paper introduced a novel experimental method, a penetration test, for asphalt mixtures to quantify the effects of glass fibre geogrids embedded in asphalt under repeated loading. It was found that the evolution of permanent deformation (εp) and its strain rate have three clearly identifiable stages. It was also observed that the presence of the geogrid increased the flow number and the number of cycles to failure significantly compared to control samples. Some of the current εp fitting models were found to be valid for deformation prediction under penetration. In addition, a new simple FN calculation method was also proposed based on strain rate and it showed consistent results. In particular, geogrid type "Grid10", which has smaller aperture size (12.7 mm) had slightly better reinforcement performance regarding the rutting resistance due to its larger contact area. Overall, the test and data analysis method presented in this study could be an important reference for future investigations on geosynthetic-reinforced pavement materials.

10.
Heliyon ; 9(9): e20005, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37810090

RESUMEN

We demonstrate improved performance of quantum dot solar cells (QDSCs) by type-II InAs/GaAsSb structure. With a moderate Sb composition of 18% and high quality QDs, a high efficiency of 17.31% under AM1.5 G illumination is achieved, showing an improvement of 11.25% in efficiency relative to type-I InAs/InGaAs QDSC. This improvement can be attributed to a high fill factor (FF) of 72.37% compared to 63% of the latter because the type-II structure effectively suppresses carrier recombination losses in QDs. As Sb composition increases to 24%, the FF maintains at a high level of 72.67%, but the efficiency drops to 17% because the elevation of valence band (VB) in GaAsSb capping layer further enhances the hole confinement. And the confinement reduces external quantum efficiency (EQE) and short-circuit current density (Jsc). These results prove the potential of improving efficiency of QDSCs by type-II structure.

11.
ACS Appl Mater Interfaces ; 15(39): 46408-46416, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37748106

RESUMEN

Radioactive iodine from nuclear waste poses a huge threat to public safety and raises concerns about environmental pollution. There is thus a growing demand for developing novel adsorbents for highly effective iodine capture. In this work, we design and synthesize three novel conjugated microporous polymers, namely, TPE-PyTTA-CMP, TPE-TAPP-CMP, and TPE-TPDA-CMP, which are constructed by an imidization reaction based on octet and tetratopic linkers. The iodine vapor adsorption experiments show that the three CMPs have an excellent iodine adsorption capacity as high as 3.10, 3.67, and 4.68 g·g-1 under 348 K and ambient pressure conditions, respectively. The adsorbed iodine in the CMPs can be released into methanol in a dramatically rapid manner, and their excellent iodine adsorption performance can still be maintained after multiple cycles. In addition, the CMPs demonstrate good adsorption performance in an n-hexane solution of iodine, and the kinetic experimental data follow the pseudo-second-order model. The hierarchical porosity, extended π-conjugated skeleton, and rich electron-donor nitrogen sites of the CMPs could contribute to their excellent iodine adsorption performance. The knowledge information obtained in this work could open up new possibilities for designing novel CMPs targeting a wide range of environment-related applications.

12.
Opt Express ; 31(15): 24173-24182, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37475250

RESUMEN

Direct epitaxial growth of group III-V light sources with excellently thermal performance on silicon photonics chips promises low-cost, low-power-consumption, high-performance photonic integrated circuits. Here, we report on the achievement of ultra-high thermal stability 1.3 µm InAs/GaAs quantum dot (QD) lasers directly grown on an on-axis Si (001) with a record-high continuous-wave (CW) operating temperature of 150 °C. A GaAs buffer layer with a low threading dislocation density (TDD) of 4.3 × 106 cm-2 was first deposited using an optimized three-step growth method by molecular beam epitaxy. Then, an eight-layer QD laser structure with p-type modulation doping to enhance the temperature stability of the device was subsequently grown on the low TDD Si-based GaAs buffer layer. It is shown that the QD laser exhibits the ultra-high temperature stability with a characteristic temperature T0=∞ and T1=∞ in the wide temperature range of 10-75 °C and 10-140 °C, respectively. Moreover, a maximum CW operating temperature of up to 150 °C and a pulsed operating temperature of up to 160 °C are achieved for the QD laser. In addition, the QD laser shows a high CW saturation power of 50 mW at 85 °C and 19 mW at 125 °C, respectively.

13.
J Neurochem ; 166(2): 265-279, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37263975

RESUMEN

Studies of the intracranial vasculature in patients with ischemic stroke caused by atherosclerosis (AS) and cardiac embolism have revealed significantly different degrees of AS, plaque, and vascular stenosis. And the endothelium has a great influence on the vasculature throughout the circulatory system, especially in the brain. This study aimed to investigate the mechanistic differences in endothelial injury between atrial fibrillation (AF)- and AS-induced ischemic stroke. All target genes of AF, AS, and the vascular endothelial cell (VC) were obtained from the GeneCards database; the differential genes of AF and AS separately associated with the VC were established by a Venn diagram. A protein-protein interaction network was created, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases were used to perform genomic enrichment and functional enrichment analysis. Hub genes were selected by Maximal Clique Centrality algorithm ranking and correlation linkage in the STRING database, and then, clinical serum samples were used to verify the quantitative expressions in the AF, AF stroke, AS, and AS stroke groups. Fifty-five AF-VC-related genes and ninety-three AS-VC-related genes were screened, which differed in biological function, cellular composition, and molecular function. The genes correlation between AF and vascular endothelial cells (VCs) was KRAS and PTPN11, and those correlation between AS and VCs was IL-4, IFNG, IL-17A, and CSF-2. IL-4 and CSF-2 may be relevant proteins involved in the differences in stroke mechanisms between AF and AS, and they may act by further influencing the function of their downstream cells. This study provides a preliminary theoretical basis for investigating the differences in mechanisms of endothelial injury between AF- and AS-induced ischemic stroke.


Asunto(s)
Aterosclerosis , Fibrilación Atrial , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Fibrilación Atrial/genética , Fibrilación Atrial/complicaciones , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Isquemia Encefálica/genética , Isquemia Encefálica/complicaciones , Células Endoteliales , Interleucina-4 , Factores de Riesgo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/complicaciones , Aterosclerosis/genética , Aterosclerosis/complicaciones , Biología Computacional , Endotelio
14.
Int J Biol Macromol ; 244: 125342, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37321434

RESUMEN

This paper explored the mechanism of dissociation of hemicellulose using lactic acid (LA)-based deep eutectic solvents (DESs) synthesized with different hydrogen bond acceptors (HBAs) via simulations. Density functional theory (DFT) calculations and molecular dynamics (MD) simulations revealed that DESs synthesized with guanidine hydrochloride (GuHCl) as hydrogen bond acceptor (HBA) demonstrated better hemicellulose solubilization compared to the conventional DESs synthesized using choline chloride (ChCl) as HBA. The best interaction with hemicellulose was achieved at GuHCl:LA = 1:1. The results showed that CL- played a dominant role in the dissolution of hemicellulose by DESs. Unlike ChCl, the guanidine group in GuHCl had the delocalized π bond, which made CL- have stronger coordination ability and promoted dissolution of hemicellulose by DESs. Moreover, multivariable analysis was employed to establish the correlation between the effects of different DESs on hemicellulose and the molecular simulation results. Additionally, the influence of different HBAs functional groups and carbon chain length on the solubilization of hemicellulose by DESs were analyzed.


Asunto(s)
Disolventes Eutécticos Profundos , Ácido Láctico , Solventes/química , Enlace de Hidrógeno , Colina/química , Modelos Teóricos
15.
Comput Biol Med ; 163: 107126, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37327757

RESUMEN

Electroencephalography (EEG) emotion recognition is a crucial aspect of human-computer interaction. However, conventional neural networks have limitations in extracting profound EEG emotional features. This paper introduces a novel multi-head residual graph convolutional neural network (MRGCN) model that incorporates complex brain networks and graph convolution networks. The decomposition of multi-band differential entropy (DE) features exposes the temporal intricacy of emotion-linked brain activity, and the combination of short and long-distance brain networks can explore complex topological characteristics. Moreover, the residual-based architecture not only enhances performance but also augments classification stability across subjects. The visualization of brain network connectivity offers a practical technique for investigating emotional regulation mechanisms. The MRGCN model exhibits average classification accuracies of 95.8% and 98.9% for the DEAP and SEED datasets, respectively, highlighting its excellent performance and robustness.


Asunto(s)
Encéfalo , Emociones , Humanos , Electroencefalografía , Entropía , Redes Neurales de la Computación
16.
Anim Nutr ; 14: 101-110, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37388162

RESUMEN

This experiment aimed to study the effects of supplemental methionine sources, 2-hydroxy-4 methyl(thio) butanoic acid (HMTBa) and DL-Methionine (DL-Met), on productive performance, egg quality, and redox status of laying ducks. A total of 792 healthy 25-wk-old Longyan laying ducks with similar body weights were randomly allotted to 11 treatment groups. Each treatment group had 6 replicates of 12 ducks. The trial lasted for 16 wk. Ducks were fed a basal deficient diet (Met: 0.24%; Met + Cys: 0.51%) or supplemented with DL-Met or HMTBa at 0.05%, 0.12%, 0.19%, 0.26%, and 0.33% of diet, respectively. Compared with the basal diet, supplementation with either DL-Met or HMTBa increased the average egg weight, egg mass, and decreased feed to egg ratio during the whole trial period (P < 0.05). Albumen weight and its ratio to total egg weight were increased, but yolk and shell ratio, albumen height, Haugh unit and shell breaking strength were decreased (P < 0.05). Dietary DL-Met or HMTBa supplementation increased taurine, methionine, leucine, tryptophan and arginine content, and decreased serine and lysine content in plasma (P < 0.05). The redox status of laying ducks was improved by enhancing the glutathione peroxidase and catalase activities, glutathione content and its ratio relative to glutathione (oxidized) content and decreasing malondialdehyde content and increasing mRNA expression of superoxide dismutase-1, glutathione peroxidase-1, hemeoxygenase-1 and nuclear factor-like 2 in liver and ileum with the supplementation of DL-Met or HMTBa (P < 0.05). Liver health status measured by average area proportion lipid droplet was improved with supplementation of DL-Met or HMTBa (P < 0.05). Villus height and villus height to crypt depth ratio in the ileum and the ileal gene expression of tight junction protein and occludin were increased with DL-Met or HMTBa supplementation (P < 0.05). Taken together, these results suggested that the efficacy of dietary supplementation of HMTBa was similar to DL-Met, and it ranged from 98% to 100% for productive performance and egg albumen ratio in laying ducks (25 to 41 wk).

17.
Spine J ; 23(11): 1721-1729, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37385409

RESUMEN

BACKGROUND CONTEXT: In the setting of "sandwich deformity" (concomitant C1 occipitalization and C2-3 nonsegmentation), the C1-2 joint becomes the only mobile joint in the craniovertebral junction. Atlantoaxial dislocation develops earlier with severer symptoms in sandwich deformity, which has been hypothesized to be due to the repetitive excessive tension in the ligaments between C1 and C2. PURPOSE: To elucidate whether and how the major ligaments of the C1-2 joint are affected in sandwich deformity, and to find out the ligament most responsible for the earlier development and severer symptoms of atlantoaxial dislocation in sandwich deformity. STUDY DESIGN: A finite element (FE) analysis study. METHODS: A three-dimensional FE model from occiput to C5 was established using anatomical data from a thin-slice CT scan of a healthy volunteer. Sandwich deformity was simulated by eliminating any C0-1 and C2-3 segmental motion respectively. Flexion torque was applied, and the range of motion of each segment and the tension sustained by the major ligaments of C1-2 (including the transverse and longitudinal bands of the cruciform ligament, the alar ligaments, and the apical ligament) were analyzed. RESULTS: Tension sustained by the longitudinal band of the cruciform ligament and the apical ligament during flexion is significantly larger in the FE model of sandwich deformity. In contrast, tension in the other ligaments is not significantly changed in the sandwich deformity model compared with the normal model. CONCLUSIONS: Considering the importance of the longitudinal band of the cruciform ligament to the stability of the C1-2 joint, our findings implicate that the early onset, severe dislocation, and unique clinical manifestations of atlantoaxial dislocation in patients with sandwich deformity are mainly due to the enlarged force loaded on the longitudinal band of the cruciform ligament. CLINICAL SIGNIFICANCE: The enlarged force loaded on the longitudinal band of the cruciform ligament can add to its laxity and thus reducing its ability to restrict the cranial migration of the odontoid process. This is in accordance with our clinical experience that dislocation of the atlantoaxial joint in patients with sandwich deformity is mainly craniocaudal, which means severer cranial neuropathy, Chiari deformity, and syringomyelia, and more difficult surgical treatment.

18.
Bioresour Technol ; 385: 129401, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37380035

RESUMEN

The interactions of three deep eutectic solvents (DES) choline chloride-glycerol (ChCl-GLY), ChCl-lactic acid (ChCl-LA) and ChCl-urea (ChCl-U) with cellulose-hemicellulose and cellulose-lignin hybrid systems were investigated using the simulated computational approach. Aiming to simulate DES pretreatment of real lignocellulosic biomass in nature. DES pretreatment could disrupt the original hydrogen bonding network structure among the lignocellulosic components and reconstruct the new DES-lignocellulosic hydrogen bonding network structure. ChCl-U had the highest intensity of action on the hybrid systems, removing 78.3% of the hydrogen bonds between cellulose-4-O-methyl Gluconic acid xylan (cellulose-Gxyl) and 68.4% of the hydrogen bonds between cellulose-Veratrylglycerol-b-guaiacyl ether (cellulose-VG), respectively. The increase of urea content facilitated the interaction between DES and lignocellulosic blend system. Finally, the addition of appropriate water (DES:H2O = 1:5) and DES formed the new DES-water hydrogen bonding network structure more favorable for the interaction of DES with lignocellulose.


Asunto(s)
Disolventes Eutécticos Profundos , Lignina , Solventes/química , Lignina/química , Celulosa/química , Agua , Biomasa , Urea/química
19.
Opt Express ; 31(12): 20449-20456, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381439

RESUMEN

We report the significantly enhanced performance of InAs/GaAs quantum dot (QD) lasers on Si(001) by spatially separated co-doping, including n-doping in the QDs and p-doping in the barrier layers simultaneously. The QD lasers are a ridge waveguide of 6 × 1000 µm2 containing five InAs QD layers. Compared with p-doped alone laser, the co-doped laser exhibits a large reduction in threshold current of 30.3% and an increase in maximum output power of 25.5% at room temperature. In the range of 15°C-115°C (under 1% pulse mode), the co-doped laser shows better temperature stability with higher characteristic temperatures of threshold current (T0) and slope efficiency (T1). Furthermore, the co-doped laser can maintain stable continuous-wave ground-state lasing up to a high temperature of 115°C. These results prove the great potential of co-doping technique for enhancing silicon-based QD laser performances towards lower power consumption, higher temperature stability, and higher operating temperature, to boost the development of high-performance silicon photonic chips.

20.
Int J Biol Macromol ; 242(Pt 2): 125004, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37217061

RESUMEN

Yam (Dioscorea spp.) is a major food source in many countries due to its tuber rich in starch (60 %-89 % of the dry weight) and various important micronutrients. Orientation Supergene Cultivation (OSC) pattern is a simple and efficient cultivation mode developed in China in recent years. However, little is known about its effect on yam tuber starch. In this study, the starchy tuber yield, starch structure and physicochemical properties were compared and analyzed in detail between OSC and Traditional Vertical Cultivation (TVC) with Dioscorea persimilis "zhugaoshu", a widely cultivated variety. The results proved that OSC significantly increased tuber yield (23.76 %-31.86 %) and commodity quality (more smooth skin) compared with TVC in three consecutive years of field experiments. Moreover, OSC increased amylopectin content, resistant starch content, granule average diameter and average degree of crystallinity by 2.7 %, 5.8 %, 14.7 % and 9.5 %, respectively, while OSC decreased starch molecular weight (Mw). These traits resulted in starch with lower thermal properties (To, Tp, Tc, ΔHgel), but higher pasting properties (PV, TV). Our results indicated that cultivation pattern affected the yam production and starch physicochemical properties. It would not only provide a practical basis for OSC promotion, but also provide valuable information on how to guide the yam starch end use in food and non-food industries.


Asunto(s)
Dioscorea , Almidón , Almidón/química , Dioscorea/química , Amilopectina , Peso Molecular , Tubérculos de la Planta
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