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Cylindrical vector beams (CVBs) exhibit great potential for multiplexing communication, owing to their mode orthogonality and compatibility with conventional wavelength multiplexing techniques. However, the practical application of CVB multiplexing communication faces challenges due to the lack of effective spatial polarization manipulation technologies for (de)multiplexing multi-dimensional physical dimensions of CVBs. Herein, we introduce a wavelength- and polarization-sensitive cascaded phase modulation strategy that utilizes multiple coaxial metasurfaces for multi-dimensional modulation of CVBs. By leveraging the spin-dependent phase modulation mechanism, these metasurfaces enable the independent transformation of the two orthogonal polarization components of CVB modes. Combined with the wavelength sensitivity of Fresnel diffraction in progressive phase modulation, this approach establishes a high-dimensional mapping relationship among CVB modes, wavelengths, spatial positions, and Gaussian fundamental modes, thereby facilitating multi-dimensional (de)multiplexing involving CVB modes and wavelengths. As a proof of concept, we theoretically demonstrate a 9-channel multi-dimensional multiplexing system, successfully achieving joint (de)multiplexing of 3 CVB modes (1, 2, and 3) and 3 wavelengths (1550â nm, 1560â nm, and 1570â nm) with a diffraction efficiency exceeding 80%. Additionally, we show the transmission of 16-QAM signals across 9 channels with the bit-error-rates below 10-5. By combining the integrability of metasurfaces with the high-dimensional wavefront manipulation capabilities of multilevel modulation, our strategy can effectively address the diverse demands of different wavelengths and CVB modes in optical communication.
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PURPOSE: We present for the first time a novel entry point of pedicle screws (Short Rod Technique, SRT), which can avoid superior facet violation and has been verified as a safe screw placement method. The purpose of this study is to determine the clinical outcomes of SRT in posterior lumbar interbody fusion (PLIF) surgery. METHODS: We retrospectively analyzed the clinical outcomes of 89 patients who received SRT and 109 patients who received PLIF surgery with regular entry points of pedicle screws with a minimum of 2 years of follow-ups. Patients were divided into three groups according to the number of fusion segments, and the clinical outcomes of the three groups were compared. RESULTS: The length of the wound and the length of rods were significantly shorter in the each SRT group. Less intraoperative blood loss was observed in the SRT group in patients with a single segment and two segments fusions, but not in three segments fusions. Fewer degenerations of the upper adjacent segment were observed in the SRT group in patients with a single segment and three segments fusions. In addition, less postoperative wound pain related to PLIF surgery was observed in the SRT group in patients with two and three segments fusions. CONCLUSION: SRT has been validated as an effective technique with good clinical outcomes, especially for reducing the occurrence of upper ASD in PLIF surgery with a single segment and three segments. The present study provides spinal surgeons with a novel method for performing PLIF surgery.
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Parafusos Pediculares , Fusão Vertebral , Humanos , Estudos Retrospectivos , Seguimentos , Vértebras Lombares/cirurgia , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Parafusos Pediculares/efeitos adversos , Dor Pós-Operatória/etiologia , Resultado do TratamentoRESUMO
Orbital angular momentum (OAM) mode offers a promising modulation dimension for high-order shift-keying (SK) communication due to its mode orthogonality. However, the expansion of modulation order through superposing OAM modes is constrained by the mode-field mismatch resulting from the rapidly increased divergence with mode orders. Herein, we address this problem by propose a phase-difference modulation strategy that breaks the limitation of modulation orders via introducing a phase-difference degree of freedom (DoF) beyond OAM modes. Phase-difference modulation exploits the sensitivity of mode interference to phase differences, thereby providing distinct tunable parameters. This enables the generation of a series of codable spatial modes with continuous variation within the same superposed OAM modes by manipulating the interference state. Due to the inherent independence between OAM mode and phase-difference DoF, the number of codable modes increases exponentially, which facilitates establishing ultra-high-order phase shift-keying by discretizing the continuous phase difference and establishing a one-to-one mapping between coding symbols and constructed modes. We show that a phase shift-keying communication link with a modulation order of up to 4 × 104 is achieved by employing only 3 OAM modes (+1, + 2 and +3), and the decode accuracy reaches 99.9%. Since the modulation order is exponentially correlated with the OAM modes and phase differences, the order can be greatly improved by further increasing the superimposed OAM modes, which may provide new insight for high-order OAM-based SK communication.
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Anti-tumor activity of Tremella fuciformis polysaccharides (TFPS) has been widely reported, but its mechanism remains poorly understood. In this study, we established an in vitro co-culture system (B16 melanoma cells and RAW 264.7 macrophage-like cells) to explore the potential anti-tumor mechanism of TFPS. Based on our results, TFPS exhibited no inhibition on the cell viability of B16 cells. However, significant apoptosis was observed when B16 cells were co-cultured with TFPS-treated RAW 264.7 cells. We further found that mRNA levels of M1 macrophage markers including iNOS and CD80 were significantly upregulated in TFPS-treated RAW 264.7 cells, while M2 macrophage markers such as Arg-1 and CD 206 remained unchanged. Besides, the migration, phagocytosis, production of inflammatory mediators (NO, IL-6 and TNF-α), and protein expression of iNOS and COX-2 were markedly enhanced in TFPS-treated RAW 264.7 cells. Network pharmacology analysis indicated that MAPK and NF-κB signaling pathways may be involved in M1 polarization of macrophages, and this hypothesis was verified by Western blot. In conclusion, our research demonstrated that TFPS induced apoptosis of melanoma cells by promoting M1 polarization of macrophages, and suggested TFPS may be applied as an immunomodulatory for cancer therapy.
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Melanoma Experimental , Camundongos , Animais , Humanos , Melanoma Experimental/patologia , Macrófagos/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Apoptose , Células RAW 264.7 , NF-kappa B/metabolismoRESUMO
Orbital angular momentum (OAM) mode multiplexing provides a new strategy for reconstructing multiple holograms, which is compatible with other physical dimensions involving wavelength and polarization to enlarge information capacity. Conventional OAM multiplexing holography usually relies on the independence of physical dimensions, and the deep holography involving spatial depth is always limited for the lack of spatiotemporal evolution modulation technologies. Herein, we introduce a depth-controllable imaging technology in OAM deep multiplexing holography via designing a prototype of five-layer optical diffractive neural network (ODNN). Since the optical propagation with dimensional-independent spatiotemporal evolution offers a unique linear modulation to light, it is possible to combine OAM modes with spatial depths to realize OAM deep multiplexing holography. Exploiting the multi-plane light conversion and in-situ optical propagation principles, we simultaneously modulate both the OAM mode and spatial depth of incident light via unitary transformation and linear modulations, where OAM modes are encoded independently for conversions among holograms. Results show that the ODNN realized light field conversion and evolution of five multiplexed OAM modes in deep multiplexing holography, where the mean square error and structural similarity index measure are 0.03 and 86%, respectively. Our demonstration explores a depth-controllable spatiotemporal evolution technology in OAM deep multiplexing holography, which is expected to promote the development of OAM mode-based optical holography and storage.
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Here we propose a polarization-dependent gradient phase modulation strategy and fabricate a local polarization-matched metasurface to add/drop polarization multiplexed cylindrical vector beams (CVBs). The two orthogonal linear polarization states in CVB multiplexing will represent as radial- and azimuthal-polarized CVBs, which means that we must introduce independent wave vectors to them for adding/dropping the polarization channels. By designing the rotation angle and geometric sizes of a meta-atom, a local polarization-matched propagation phase plasmonic metasurface is constructed, and the polarization-dependent gradient phases were loaded to perform this operation. As a proof of concept, the polarization multiplexed CVBs, carrying 150-Gbit/s quadrature phase shift keying signals, are successfully added and dropped, and the bit error rates approach 1 × 10-6. In addition to representing a route for adding/dropping polarization multiplexed CVBs, other functional phase modulation of arbitrary orthogonal linear polarization bases is expected, which might find potential applications in polarization encryption imaging, spatial polarization shaping, etc.
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Vortex beams have application potential in multiplexing communication because of their orthogonal orbital angular momentum (OAM) modes. OAM add-drop multiplexing remains a challenge owing to the lack of mode selective coupling and separation technologies. We proposed an OAM add-drop multiplexer (OADM) using an optical diffractive deep neural network (ODNN). By exploiting the effective data-fitting capability of deep neural networks and the complex light-field manipulation ability of multilayer diffraction screens, we constructed a five-layer ODNN to manipulate the spatial location of vortex beams, which can selectively couple and separate OAM modes. Both the diffraction efficiency and mode purity exceeded 95% in simulations and four OAM channels carrying 16-quadrature-amplitude-modulation signals were successfully downloaded and uploaded with optical signal-to-noise ratio penalties of â¼1â dB at a bit error rate of 3.8 × 10-3. This method can break through the constraints of conventional OADM, such as single function and poor flexibility, which may create new opportunities for OAM multiplexing and all-optical interconnection.
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Human operators have the trend of increasing physical and mental workloads when performing teleoperation tasks in uncertain and dynamic environments. In addition, their performances are influenced by subjective factors, potentially leading to operational errors or task failure. Although agent-based methods offer a promising solution to the above problems, the human experience and intelligence are necessary for teleoperation scenarios. In this paper, a truncated quantile critics reinforcement learning-based integrated framework is proposed for human-agent teleoperation that encompasses training, assessment and agent-based arbitration. The proposed framework allows for an expert training agent, a bilateral training and cooperation process to realize the co-optimization of agent and human. It can provide efficient and quantifiable training feedback. Experiments have been conducted to train subjects with the developed algorithm. The performances of human-human and human-agent cooperation modes are also compared. The results have shown that subjects can complete the tasks of reaching and picking and placing with the assistance of an agent in a shorter operational time, with a higher success rate and less workload than human-human cooperation.
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Robótica , Algoritmos , Retroalimentação , Humanos , Aprendizagem , Interface Usuário-ComputadorRESUMO
CRISPR/Cas9 is a powerful technology widely used for genome editing, with the potential to be used for correcting a wide variety of deleterious disease-causing mutations. However, the technique tends to generate more indels (insertions and deletions) than precise modifications at the target sites, which might not resolve the mutation and could instead exacerbate the initial genetic disruption. We sought to develop an improved protocol for CRISPR/Cas9 that would correct mutations without unintended consequences. As a case study, we focused on achondroplasia, a common genetic form of dwarfism defined by missense mutation in the Fgfr3 gene that results in glycine to arginine substitution at position 374 in mice in fibroblast growth factor receptor 3 (Fgfr3-G374R), which corresponds to G380R in humans. First, we designed a GFP reporter system that can evaluate the cutting efficiency and specificity of single guide RNAs (sgRNAs). Using the sgRNA selected based on our GFP reporter system, we conducted targeted therapy of achondroplasia in mice. We found that we achieved higher frequency of precise correction of the Fgfr3-G374R mutation using Cas9 protein rather than Cas9 mRNA. We further demonstrated that targeting oligos of 100 and 200 nucleotides precisely corrected the mutation at equal efficiency. We showed that our strategy completely suppressed phenotypes of achondroplasia and whole genome sequencing detected no off-target effects. These data indicate that improved protocols can enable the precise CRISPR/Cas9-mediated correction of individual mutations with high fidelity.
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Acondroplasia/terapia , Sistemas CRISPR-Cas , Marcação de Genes , Mutação , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/fisiologia , Acondroplasia/genética , Animais , Feminino , Edição de Genes , Masculino , Camundongos , Camundongos Knockout , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genéticaRESUMO
Glucose and glutamine are two essential ingredients for cell growth. Glycolysis and glutaminolysis can be linked by glutamine: fructose-6-phosphate aminotransferase (GFAT, composed of GFAT1 and GFAT2) that catalyzes the synthesis of glucosamine-6-phosphate and glutamate by using fructose-6-phosphate and glutamine as substrates. The role of mammalian target of rapamycin (MTOR, composed of MTOR1 and MTOR2) in regulating glycolysis has been explored in human cancer cells. However, whether MTOR can interact with GFAT to regulate glucosamine-6-phosphate is poorly understood. In this study, we report that GFAT1 is essential to maintain the malignant features of GBM cells. And MTOR2 rather than MTOR1 plays a robust role in promoting GFAT1 protein activity, and accelerating the progression of glucosamine-6-phosphate synthesis, which is not controlled by the PI3K/AKT signaling. Intriguingly, high level of glucose or glutamine supply promotes MTOR2 protein activity. In turn, up-regulating glycolytic and glutaminolytic metabolisms block MTOR dimerization, enhancing the release of MTOR2 from the MTOR complex. As a transcriptional factor, C-MYC, directly targeted by MTOR2, promotes the relative mRNA expression level of GFAT1. Notably, our data reveal that GFAT1 immunoreactivity is positively correlated with the malignant grades of glioma patients. Kaplan-Meier assay reveals the correlations between patients' 5-year survival and high GFAT1 protein expression. Taken together, we propose that the MTOR2/C-MYC/GFAT1 axis is responsible for the modulation on the crosstalk between glycolysis and glutaminolysis in GBM cells. Under the condition of accelerated glycolytic and/or glutaminolytic metabolisms, the MTOR2/C-MYC/GFAT1 axis will be up-regulated in GBM cells.
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Glioblastoma/metabolismo , Glucosamina/análogos & derivados , Glucose-6-Fosfato/análogos & derivados , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Glutamina/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Glucosamina/biossíntese , Glucose/metabolismo , Glucose-6-Fosfato/biossíntese , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/metabolismo , Multimerização Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
As a crucial protein, the herpes simplex virus 1 (HSV-1) UL2 protein has been shown to take part in various stages of viral infection, nonetheless, its exact subcellular localization and transport molecular determinants are not well known thus far. In the present study, by using live cells fluorescent microscopy assay, UL2 tagged with enhanced yellow fluorescent protein was transiently expressed in live cells and showed a completely nuclear accumulation without the presence of other HSV-1 proteins. Moreover, the nuclear transport of UL2 was characterized to be assisted by multiple transport pathways through Ran-, importin α1-, α5-, α7-, ß1- and transportin-1 cellular transport receptors. Consequently, these results will improve understanding of UL2-mediated biological functions in HSV-1 infection cycles.
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Herpes Simples/fisiopatologia , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Uracila-DNA Glicosidase/metabolismo , Proteínas Virais/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Células COS , Núcleo Celular/metabolismo , Chlorocebus aethiops , Células HEK293 , Humanos , Frações Subcelulares , Distribuição Tecidual , Uracila-DNA Glicosidase/genética , Proteínas Virais/genética , alfa Carioferinas/metabolismo , beta Carioferinas/metabolismoRESUMO
Nuclear magnetic resonance (NMR) spectroscopy has long served as an irreplaceable, versatile tool in physics, chemistry, biology, and materials sciences, owing to its ability to study molecular structure and dynamics in detail. In particular, the connectivity of chemical sites within molecules, and thereby molecular structure, becomes visible by multi-dimensional NMR. Homonuclear correlation experiments are a powerful tool for identifying coupled spins. Generally, diagonal peaks in these correlation spectra display the strongest intensities and do not offer any new information beyond the standard one-dimensional spectrum, whereas weaker, symmetrically placed cross peaks contain most of the coupling information. The cross peaks near the diagonal are often affected by the tails of strong diagonal peaks or even obscured entirely by the diagonal. In this paper, we demonstrate a homonuclear encoding approach based on imparting a discrete phase modulation of the targeted cross peaks and combine it with a site-selective sculpting scheme, capable of simplifying the patterns arising in these 2D correlation spectra. The theoretical principles of the new methods are laid out, and experimental observations are rationalized on the basis of theoretical analyses. The ensuing techniques provide a new way to retrieve 2D coupling information within homonuclear spin systems, with enhanced sensitivity, speed, and clarity.
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Chemical compositions, antioxidative, antimicrobial, anti-inflammatory, and cytotoxic activities of essential oils extracted from four common Curcuma species (Curcuma longa, Curcuma phaeocaulis, Curcuma wenyujin, and Curcuma kwangsiensis) rhizomes in P. R. China are comparatively studied. In total, 47, 49, 35, and 30 compounds are identified in C. longa, C. phaeocaulis, C. wenyujin, and C. kwangsiensis essential oils by GC/MS, and their richest compounds are ar-turmerone (21.67%), elemenone (19.41%), curdione (40.23%) and (36.47%), respectively. Moreover, C. kwangsiensis essential oils display the strongest DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity (IC50 , 3.47 µg/ml), much higher than ascorbic acid (6.50 µg/ml). C. phaeocaulis oils show the best antibacterial activities against Escherichia coli (MIC, 235.54 µg/ml), Pseudomonas aeruginosa (391.31 µg/ml) and Staphylococcus aureus (378.36 µg/ml), while C. wenyujin and C. kwangsiensis oils show optimum activities against Candida albicans (208.61 µg/ml) and Saccharomyces cerevisiae (193.27 µg/ml), respectively. C. phaeocaulis (IC50 , 4.63 µg/ml) and C. longa essential oils (73.05 µg/ml) have the best cytotoxicity against LNCaP and HepG2, respectively. C. kwangsiensis oils also exhibit the strongest anti-inflammatory activities by remarkably down-regulating expression of COX-2 and TNF-α. Therefore, due to their different chemical compositions and bioactivities, traditional Chinese Curcuma herbs should be differentially served as natural additives for food, pharmaceutical, and cosmetic.
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Curcuma/química , Óleos Voláteis/química , Animais , Anti-Infecciosos/análise , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/análise , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/análise , Antioxidantes/química , Candida albicans/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Curcuma/metabolismo , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo/efeitos dos fármacos , Edema/induzido quimicamente , Edema/metabolismo , Edema/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas , Células Hep G2 , Humanos , Camundongos , Óleos Voláteis/análise , Ésteres de Forbol/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The chemical compositions of essential oils (EOs) extracted from Curcuma kwangsiensis rhizomes collected from six natural habitats in P. R. China were evaluated using gas chromatography/mass spectrometry (GC/MS). Fifty-seven components were identified from the six EOs, and their main constituents were 8,9-dehydro-9-formyl-cycloisolongifolene (2.37 - 42.59%), germacrone (6.53 - 22.20%), and l-camphor (0.19 - 6.12%). The six EOs exhibited different DPPH radical-scavenging activities (IC50 , 2.24 - 31.03 µg/ml), with the activity of most of EOs being much higher than that of Trolox C (IC50 , 10.49 µg/ml) and BHT (IC50 , 54.13 µg/ml). Most EOs had potent antimicrobial effects against the tested bacteria and fungus. They also exhibited cytotoxicity against B16 (IC50 , 4.44 - 147.4 µg/ml) and LNCaP cells (IC50 , 73.94 - 429.25 µg/ml). The EOs showed excellent anti-inflammatory action by significantly downregulating expression of pro-inflammatory cytokines, cyclooxygenase-2, and tumor necrosis factor-α. This study provides insight into the interrelation among growth location, phytoconstituents, and bioactivities, and the results indicate the potential of C. kwangsiensis as natural nutrients, medicines, and others additives.
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Curcuma/química , Óleos Voláteis/química , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , China , Ecossistema , Sequestradores de Radicais Livres , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Concentração Inibidora 50 , Melanoma Experimental/patologiaRESUMO
The prevalence of late-life schizophrenia is increasing with high burden. It is well-documented that schizophrenia affects men and women differently in terms of symptoms. Sex hormones, which play a role in the pathology and symptoms of schizophrenia, are greatly affected by aging. To the best of our knowledge, this is a study to examine the sex differences in psychiatric symptoms and their correlation with sex hormones in participants with late-life schizophrenia. Positive and Negative Syndrome Scale (PANSS) factors were evaluated. Testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, progesterone, and prolactin were measured. Male participants with late-life schizophrenia had more severe negative symptoms than female participants (z = -2.56, P = 0.010), while female participants had more severe anxiety/depression compared to male participants (z = 2.64, P = 0.008). Testosterone levels in male participants were positively associated with negative symptoms (ß = 0.23, t = 2.27, P = 0.025), while there was no significant association between sex hormones and symptoms in female participants. In conclusion, higher testosterone levels were associated with more severe negative symptoms in male participants with late-life schizophrenia, suggesting that attention should be paid to the sex differences in late-life schizophrenia in clinical practice.
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Hormônios Esteroides Gonadais , Esquizofrenia , Caracteres Sexuais , Humanos , Masculino , Feminino , Esquizofrenia/sangue , Esquizofrenia/fisiopatologia , Idoso , Hormônios Esteroides Gonadais/sangue , Pessoa de Meia-Idade , Testosterona/sangue , Estradiol/sangue , Hormônio Luteinizante/sangue , Escalas de Graduação Psiquiátrica , Prolactina/sangue , Progesterona/sangue , Hormônio Foliculoestimulante/sangueRESUMO
BACKGROUND CONTEXT: Large annulus fibrosus (AF) defects often lead to a high rate of reherniation, particularly in the medial AF region, which has limited self-healing capabilities. The increasing prevalence of herniated discs underscores the need for effective repair strategies. PURPOSE: The objectives of this study were to design an AF repair technique to reduce solve the current problems of insufficient mechanical properties and poor sealing capacity. STUDY DESIGN: In vitro biomechanical experiments and finite element analysis. METHODS: The materials used in this study were patches and hydrogels with good biocompatibility and sufficient mechanical properties to withstand loading in the lumbar spine. Five repair techniques were assessed in this study: hydrogel filler (HF), AF patch medial barrier (MB), AF patch medial barrier and hydrogel filler (MB&HF), AF patch medial-lateral barrier (MLB), and AF patch medial-lateral barrier and hydrogel filler (MLB&HF). The repair techniques were subjected to in vitro testing (400 N axial compression and 0-500 N fatigue loading at 5Hz) and finite element analysis (400 N axial compression) to evaluate the effectiveness at repairing large AF defects. The evaluation included repair tightness, spinal stability, and fatigue resistance. RESULTS: From the in vitro testing, the failure load of the repair techniques was in the following order HF
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STUDY DESIGN: Biomechanical testings and finite element analysis. OBJECTIVES: This study aims to investigate how annulus fibrosus (AF) incision size (RIS, Ratio of incision width to AF height) and shape affect intervertebral disc (IVD) biomechanics. METHODS: A validated finite element model of lumbar spines simulated various incisions in the middle-right posterior region of the AF, with different sizes and shapes. Simulations included axial compression, flexion, extension, bending, and rotation. Parameters assessed included stability, re-herniation, and IVD degeneration by analyzing stress, height, Intradiscal pressure (IDP), and the range of motion (ROM). RESULTS: Incision increased AF stress and ROM under 3 Nm moment, with values rising as RIS increased. RIS exceeding 40% resulted in a 20% AF stress increase during compression and extension, while RIS over 50% led to over 20% AF stress increase during other motions. Incision stress also increased with higher RIS, particularly surpassing 50% RIS. IDP rose across all incision shapes. Endplate stress increased (9.9%-48.9%) with larger incisions, with average increases of 12.8%, 12.7%, 30.5%, and 22.8% for circular, oval, square, and rectangular incisions. Compression and rotation minimally affected NP pressure (<15%), while flexion (19.8%-38.8%) and bending (18.5%-43.9%) had a more pronounced effect. ROM increased with RIS (20.0% â¼ 77.4%), especially with an incision RIS exceeding 40%. CONCLUSIONS: AF injury elevates AF stress, reduces spine stability, heightens degeneration risk with increasing RIS. Reherniation risk rises when RIS exceeds 40%. Circular or oval incisions maintain spine biomechanics better than square or rectangular ones.
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OBJECTIVE: To investigate the cell viabilities of vascular smooth muscle cells and vascular endothelial cells stimulated by cigarette smoke extract(CSE) . METHODS: The CSE was prepared by smoke-bubbled phosphate buffered saline(PBS) generation.After culturing cells with different concentrations of CSE, we used the cell counting kit-8 to determine the cell viability.The expression levels of c-jun and cyclinD1 were analyzed through Western blot.The c-jun plasmid was transfected to detect the change of cyclinD1 expression. RESULTS: The smooth muscle cell viability increased when the CSE concentration ranged 0.625%-10%, whereas the endothelial cells viability decreased when exposed to the CSE concentration. After exposure to CSE for 48 hours, there was no difference in c-jun expression between toxin group and PBS group;however, the expression of p-c-jun in the smooth muscle cells significantly increased in the toxin groups than in the PBS group(P<0.05) and the expression of p-c-jun in the vascular endothelial cells significantly decreased(P<0.05) . The level of cyclinD1 significantly increased after exposed to CSE, and its expression level also increased in respond to the c-jun overexpression. CONCLUSION: CSE can enhance the proliferation of vascular smooth muscle cells and decrease in the activity of endothelial cells proliferation, which may be explained by the phosphorylation of c-jun and the expression of cyclinD1.
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Ciclina D1/metabolismo , Células Endoteliais/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Nicotiana/efeitos adversos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Células Endoteliais/metabolismo , Humanos , Miócitos de Músculo Liso/metabolismoRESUMO
Objective: The purpose of this study was to analyze the feasibility of repairing a ruptured intervertebral disc using a patch secured to the inner surface of the annulus fibrosus (AF). Different material properties and geometries for the patch were evaluated. Methods: Using finite element analysis, this study created a large box-shaped rupture in the posterior-lateral region of the AF and then repaired it with a circular and square inner patch. The elastic modulus of the patches ranged from 1 to 50 MPa to determine the effect on the nucleus pulposus (NP) pressure, vertical displacement, disc bulge, AF stress, segmental range of motion (ROM), patch stress, and suture stress. The results were compared against the intact spine to determine the most suitable shape and properties for the repair patch. Results: The intervertebral height and ROM of the repaired lumbar spine was similar to the intact spine and was independent of the patch material properties and geometry. The patches with a modulus of 2-3 MPa resulted in an NP pressure and AF stresses closest to the healthy disc, and produced minimal contact pressure on the cleft surfaces and minimal stress on the suture and patch of all models. Circular patches caused lower NP pressure, AF stress and patch stress than the square patch, but also caused greater stress on the suture. Conclusion: A circular patch with an elastic modulus of 2-3 MPa secured to the inner region of the ruptured annulus fibrosus was able to immediately close the rupture and maintain an NP pressure and AF stress similar to the intact intervertebral disc. This patch had the lowest risk of complications and produced the greatest restorative effect of all patches simulated in this study.
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A novel interlaminar elastic screw spacer technique was designed to maintain lumbar mobility in treating lumbar degenerative diseases. A validated finite element model of L4/5 was used to establish an ISES-1/2 model and an ISES-1/3 model based on different insertion points, a unilateral fixation model and a bilateral fixed model based on different fixation methods, and a Coflex-F model based on different implants. The elastic rods were used to fix screws. Under the same mechanical conditions, we compared the biomechanical characteristics to investigate the optimal entry point for ISES technology, demonstrate the effectiveness of unilateral fixation, and validate the feasibility of the ISES technique. Compared to ISES-1/3, the ISES-1/2 model had lower intradiscal pressure, facet cartilage stress, and posterior structural stress. Compared to the ISES-BF model, the ISES-UF model had lower intervertebral pressure, larger mobility, and smaller stress on the posterior structures. The ISES model had a similar intervertebral pressure and limitation of extension as the Coflex-F model. The ISES model retained greater mobility and reduced the stress on the facet cartilage and posterior structure compared with the Coflex-F model. Our study suggests that the ISES technique is a promising treatment of lumbar degenerative diseases, especially those with osteoporosis.