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1.
Ambio ; 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38564103

ABSTRACT

When accounting for the social-ecological impact of an ecological restoration program, both objective environmental contexts and people's subjective perceptions are required. While this kind of environmental impact assessment lacks a comprehensive perspective. We use the difference-in-differences model to evaluate the effect of the greenness of the landscape after ecological migration in the Qilian Mountains in China; and analysis of variance and fixed effects models are used to evaluate the effects of such ecological restoration programs on local people's perceptions. The results show that the ecological migration program in the Qilian Mountains has been successful at not only significantly improving remotely sensed greenness at the landscape scale, but also at enhancing immigrants' environmental perceptions. These findings demonstrate the environmental impacts of ecological migration from a social-ecological perspective, and can provide methodological implications for landscape planning to support a better understanding of ecological restoration programs in the drylands.

2.
Lung Cancer ; 189: 107451, 2024 03.
Article in English | MEDLINE | ID: mdl-38354535

ABSTRACT

OBJECTIVES: Canakinumab, an interleukin-1 beta inhibitor, previously showed reduced lung cancer incidence and mortality (CANTOS). Here, we compare the efficacy/safety of canakinumab versus placebo in patients with advanced non-small cell lung cancer (NSCLC) who had progressed after platinum-based doublet chemotherapy (PDC) and immunotherapy. MATERIALS AND METHODS: CANOPY-2, a randomized, double-blind, phase 3 trial, enrolled adult patients with stage IIIB/IV NSCLC, without EGFR or ALK alterations, who had received one prior PDC regimen and one prior programmed death-1/programmed death-ligand 1 inhibitor and experienced subsequent disease progression. Patients were randomized to canakinumab plus docetaxel or placebo plus docetaxel. RESULTS: A total of 237 patients were randomly allocated: 120 (51 %) to canakinumab and 117 (49 %) to placebo, stratified by histology and prior lines of therapy. Three patients in the placebo arm did not receive study treatment. The trial did not meet its primary endpoint of overall survival: median 10.6 months (95 % confidence interval [CI], 8.2-12.4) for the canakinumab arm and 11.3 months (95 % CI, 8.5-13.8) for the placebo arm (hazard ratio, 1.06 [95 % CI, 0.76-1.48]; one-sided P-value = 0.633). AEs (any grade) were reported in 95 % of patients in the canakinumab group and in 98 % of patients in the placebo group. Grade 3-4 AEs were experienced by 62 % and 64 % of patients in the canakinumab and placebo groups, respectively, and grade 5 AEs were experienced by 8 % and 5 %. Prespecified, post-hoc subgroup analyses showed that patients with undetected circulating tumor DNA (ctDNA) and/or lower levels (< 10 mg/L) of C-reactive protein (CRP) achieved longer progression-free and overall survival than those with detected ctDNA or higher (≥ 10 mg/L) CRP levels. There was no association with treatment arm. CONCLUSION: Adding canakinumab to docetaxel did not provide additional benefit for patients with advanced NSCLC who had progressed after PDC and immunotherapy. CLINICAL REGISTRATION: NCT03626545.


Subject(s)
Antibodies, Monoclonal, Humanized , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Adult , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Docetaxel/therapeutic use , Lung Neoplasms/drug therapy , Immunotherapy
3.
BMC Musculoskelet Disord ; 25(1): 129, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38347518

ABSTRACT

OBJECTIVE: To study the biomechanical characteristics of each tissue structure when using different 3D printing Cage in osteoporotic patients undergoing interbody fusion. METHODS: A finite element model of the lumbar spine was reconstructed and validated with regarding a range of motion and intervertebral disc pressure from previous in vitro studies. Cage and pedicle screws were implanted and part of the lamina, spinous process, and facet joints were removed in the L4/5 segment of the validated mode to simulate interbody fusion. A 280 N follower load and 7.5 N·m moment were applied to different postoperative models and intact osteoporotic model to simulate lumbar motion. The biomechanical characteristics of different models were evaluated by calculating and analyzing the range of motion of the fixed and cephalic adjacent segment, the stress of the screw-rod system, the stress at the interface between cage and L5 endplate, and intervertebral disc pressure of the adjacent segment. RESULTS: After rigid fixation, the range of motion of the fixed segment of model A-C decreased significantly, which was much smaller than that of the osteoporotic model. And with the increase of the axial area of the interbody fusion cages, the fixed segment of model A-C tended to be more stable. The range of motion and intradiscal pressure of the spinal models with different interbody fusion cages were higher than those of the complete osteoporosis model, but there was no significant difference between the postoperative models. On the other hand, the L5 upper endplate stress and screw-rod system stress of model A-C show a decreasing trend in different directions of motion. The stress of the endplate is the highest during flexion, which can reach 40.5 MPa (model A). The difference in endplate stress between models A-C was the largest during lateral bending. The endplate stress of models A and B was 150.5% and 140.9% of that of model C, respectively. The stress of the screw-rod system was the highest during lateral bending (model A, 102.0 MPa), which was 108.4%, 102.4%, 110.4%, 114.2% of model B and 158.5%, 110.1%, 115.8%, 125.4% of model C in flexion, extension, lateral bending, and rotation, respectively. CONCLUSIONS: For people with osteoporosis, no matter what type of cage is used, good immediate stability can be achieved after surgery. Larger cage sizes provide better fixation without significantly increasing ROM and IDP in adjacent segments, which may contribute to the development of ASD. In addition, larger cage sizes can disperse endplate stress and reduce stress concentration, which is of positive significance in preventing cage subsidence after operation. The cage and screw rod system establish a stress conduction pathway on the spine, and a larger cage greatly enhances the stress-bearing capacity of the front column, which can better distribute the stress of the posterior spine structure and the stress borne by the posterior screw rod system, reduce the stress concentration phenomenon of the nail rod system, and avoid exceeding the yield strength of the material, resulting in the risk of future instrument failure.


Subject(s)
Osteoporosis , Pedicle Screws , Spinal Fusion , Humans , Finite Element Analysis , Spinal Fusion/methods , Biomechanical Phenomena , Range of Motion, Articular , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Osteoporosis/surgery
4.
Metab Brain Dis ; 39(4): 625-633, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38416338

ABSTRACT

Selenium-containing agents showed novel anticancer activity by triggering pro-oxidative mechanism. Studies confirmed that methylseleninic acid (MeSe) displayed broad-spectrum anti-tumor activity against kinds of human cancers. However, the anticancer effects and mechanism of MeSe against human glioma growth have not been explored yet. Herein, the present study showed that MeSeA dose-dependently inhibited U251 and U87 human glioma cells growth in vitro. Flow cytometry analysis indicated that MeSe induced significant U251 cells apoptosis with a dose-dependent manner, followed by the activation of caspase-7, caspase-9 and caspase-3. Immunofluorescence staining revealed that MeSe time-dependently caused reactive oxide species (ROS) accumulation and subsequently resulted in oxidative damage, as convinced by the increased phosphorylation level of Ser428-ATR, Ser1981-ATM, Ser15-p53 and Ser139-histone. ROS inhibition by glutathione (GSH) effectively attenuated MeSe-induced ROS generation, oxidative damage, caspase-3 activation and cytotoxicity, indicating that ROS was an upstream factor involved in MeSe-mediated anticancer mechanism in glioma. Importantly, MeSe administration in nude mice significantly inhibited glioma growth in vivo by inducing apoptosis through triggering oxidative damage. Taken together, our findings validated the possibility that MeSe as a selenium-containing can act as potential tumor chemotherapy agent for therapy of human glioma.


Subject(s)
Apoptosis , Glioma , Mice, Nude , Organoselenium Compounds , Oxidative Stress , Reactive Oxygen Species , Humans , Glioma/drug therapy , Glioma/metabolism , Glioma/pathology , Apoptosis/drug effects , Organoselenium Compounds/pharmacology , Organoselenium Compounds/therapeutic use , Animals , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Oxidative Stress/drug effects , Mice , Antineoplastic Agents/pharmacology , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Xenograft Model Antitumor Assays , Cell Proliferation/drug effects , Mice, Inbred BALB C
5.
Heliyon ; 9(8): e18430, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37533976

ABSTRACT

Background: Exposure to Migraine may be one of the risk factors for the onset of rheumatoid arthritis (RA), while the relationship between the two is debatable. In this study, the connection between migraine and the risk of RA was investigated using a systematic review and meta-analysis of the pertinent literature. Methods: Up to July 2022, the PubMed, EMBASE, Web of Science (WOS), and scopus databases were employed to search for observational studies on the risk of RA in migraineurs. The effect sizes were pooled using a random-effects model or a fixed-effects model. Results: Out of 2345 records, 5 studies (3 case and control studies and 2 cohort studies) were identified and included in the meta-analysis. According to a pooled analysis, migraine sufferers had a higher chance of developing RA (pooled adjusted effect estimate: 1.94, 95% confidence interval: 1.74-2.17; p < 0.01). Conclusions: Migraine can be legitimately regarded as a risk factor for RA since this study demonstrated a relationship between migraine and RA. This conclusion should be treated with caution due to low power and precision. Rigorous design and larger sample sizes of studies are needed to verify the findings.

6.
BMC Musculoskelet Disord ; 24(1): 695, 2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37649054

ABSTRACT

OBJECTIVE: This study aimed to compare the biomechanical properties of lumbar interbody fusion involving two types of cages. The study evaluated the effectiveness of the cage spanning the ring apophysis, regardless of the endplate's integrity. METHODS: A finite element model of the normal spine was established and validated in this study. The validated model was then utilized to simulate Lateral Lumbar Interbody Fusion (LLIF) with posterior pedicle screw fixation without posterior osteotomy. Two models of interbody fusion cage were placed at the L4/5 level, and the destruction of the bony endplate caused by curetting the cartilaginous endplate during surgery was simulated. Four models were established, including Model 1 with an intact endplate and long cage spanning the ring apophysis, Model 2 with endplate decortication and long cage spanning the ring apophysis, Model 3 with an intact endplate and short cage, and Model 4 with endplate decortication and short cage. Analyzed were the ROM of the fixed and adjacent segments, screw rod system stress, interface stress between cage and L5 endplate, trabecular bone stress on the upper surface of L5, and intervertebral disc pressure (IDP) of adjacent segments. RESULTS: There were no significant differences in ROM and IDP between adjacent segments in each postoperative model. In the short cage model, the range of motion (ROM), contact pressure between the cage and endplate, stress in L5 cancellous bone, and stress in the screw-rod system all exhibited an increase ranging from 0.4% to 79.9%, 252.9% to 526.9%, 27.3% to 133.3%, and 11.4% to 107%, respectively. This trend was further amplified when the endplate was damaged, resulting in a maximum increase of 88.6%, 676.1%, 516.6%, and 109.3%, respectively. Regardless of the integrity of the endplate, the long cage provided greater support strength compared to the short cage. CONCLUSIONS: Caution should be exercised during endplate preparation and cage placement to maintain the endplate's integrity. Based on preoperative X-ray evaluation, the selection of a cage that exceeds the width of the pedicle by at least 5 mm (ensuring complete coverage of the vertebral ring) has demonstrated remarkable biomechanical performance in lateral lumbar interbody fusion procedures. By opting for such a cage, we expect a reduced occurrence of complications, including cage subsidence, internal fixation system failure, and rod fracture.


Subject(s)
Fractures, Bone , Pedicle Screws , Humans , Finite Element Analysis , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Cancellous Bone
7.
Leukemia ; 37(8): 1709-1718, 2023 08.
Article in English | MEDLINE | ID: mdl-37420006

ABSTRACT

Aberrant innate immune signaling has been identified as a potential key driver of the complex pathophysiology of myelodysplastic neoplasms (MDS). This study of a large, clinically and genetically well-characterized cohort of treatment-naïve MDS patients confirms intrinsic activation of inflammatory pathways in general mediated by caspase-1, interleukin (IL)-1ß and IL-18 in low-risk (LR)-MDS bone marrow and reveals a previously unrecognized heterogeneity of inflammation between genetically defined LR-MDS subgroups. Principal component analysis resolved two LR-MDS phenotypes with low (cluster 1) and high (cluster 2) levels of IL1B gene expression, respectively. Cluster 1 contained 14/17 SF3B1-mutated cases, while cluster 2 contained 8/8 del(5q) cases. Targeted gene expression analysis of sorted cell populations showed that the majority of the inflammasome-related genes, including IL1B, were primarily expressed in the monocyte compartment, consistent with a dominant role in determining the inflammatory bone marrow environment. However, the highest levels of IL18 expression were found in hematopoietic stem and progenitor cells (HSPCs). The colony forming activity of healthy donor HSPCs exposed to monocytes from LR-MDS was increased by the IL-1ß-neutralizing antibody canakinumab. This work reveals distinct inflammatory profiles in LR-MDS that are of likely relevance to the personalization of emerging anti-inflammatory therapies.


Subject(s)
Myelodysplastic Syndromes , Humans , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/metabolism , Hematopoietic Stem Cells/metabolism , Bone Marrow/metabolism , Signal Transduction , Gene Expression Profiling
9.
Front Chem ; 11: 1163178, 2023.
Article in English | MEDLINE | ID: mdl-37153526

ABSTRACT

A self-assembled tetrahedral cage results from two C 3-symmetry building blocks, namely, homooxacalix[3]arene tricarboxylate and uranyl cation, as demonstrated by X-ray crystallography. In the cage, four metals coordinate at the lower rim with the phenolic and ether oxygen atoms to shape the macrocycle with appropriate dihedral angles for tetrahedron formation, whereas four additional uranyl cations further coordinate at the upper-rim carboxylates to finalize the assembly. Counterions dictate the filling and porosity of the aggregates, whereas potassium induces highly porous structures, and tetrabutylammonium yields compact, densely packed frameworks. The tetrahedron metallo-cage complements our previous report (Pasquale et al., Nat. Commun., 2012, 3, 785) on uranyl-organic frameworks (UOFs) from calix[4]arene and calix[5]arene carboxylates (octahedral/cubic and icosahedral/dodecahedral giant cages, respectively) and completes the assembly of all five Platonic solids from just two chemical components.

10.
J Orthop Surg Res ; 18(1): 366, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37198649

ABSTRACT

BACKGROUND: Pelvic parameters have been taken into consideration for the evaluation of the outcomes of bracing in AIS. To discuss the stress required to correct the pelvic deformity related to Lenke5 adolescent idiopathic scoliosis (AIS) by finite element analysis, and provide a reference for the shaping of the pelvic region of the brace. METHODS: An three-dimensional (3D) corrective force on the pelvic area was defined. Computed tomography images were used to reconstruct a 3D model of Lenke5 AIS. Computer-aided engineering software Abaqus was used to implement finite element analysis. By adjusting the magnitude and position of corrective forces, coronal pelvic coronal plane rotation (PCPR) and Cobb angle (CA) of lumbar curve in the coronal plane, horizontal pelvic axial plane rotation, and apical vertebra rotation (AVR) were minimized to achieve the best effect on the spine and pelvic deformity correction. The proposed corrective conditions were divided into three groups: (1) forces applied on X-axis; (2) forces applied both in the X- and Y-axis; and (3) forces applied along the X-, Y-, and Z-axis at the same time. RESULTS: In three groups, CA correction reduced by 31.5%, 42.5%, and 59.8%, and the PCPR changed to 12°, 13°, and 1° from 6.5°, respectively. The best groups of correction forces should simultaneously locate on the sagittal, transverse, and coronal planes of the pelvis. CONCLUSIONS: For Lenke5 AIS, 3D correction forces can sufficiently reduce scoliosis and pelvic asymmetrical state. Force applied along the Z-axis is vital to correct the pelvic coronal pelvic tilt associated with Lenke5 AIS.


Subject(s)
Kyphosis , Scoliosis , Humans , Adolescent , Scoliosis/diagnostic imaging , Finite Element Analysis , Retrospective Studies , Spine , Dioctyl Sulfosuccinic Acid , Thoracic Vertebrae
11.
Cancer Immunol Res ; 11(6): 777-791, 2023 06 02.
Article in English | MEDLINE | ID: mdl-37040466

ABSTRACT

High levels of IL1ß can result in chronic inflammation, which in turn can promote tumor growth and metastasis. Inhibition of IL1ß could therefore be a promising therapeutic option in the treatment of cancer. Here, the effects of IL1ß blockade induced by the mAbs canakinumab and gevokizumab were evaluated alone or in combination with docetaxel, anti-programmed cell death protein 1 (anti-PD-1), anti-VEGFα, and anti-TGFß treatment in syngeneic and humanized mouse models of cancers of different origin. Canakinumab and gevokizumab did not show notable efficacy as single-agent therapies; however, IL1ß blockade enhanced the effectiveness of docetaxel and anti-PD-1. Accompanying these effects, blockade of IL1ß alone or in combination induced significant remodeling of the tumor microenvironment (TME), with decreased numbers of immune suppressive cells and increased tumor infiltration by dendritic cells (DC) and effector T cells. Further investigation revealed that cancer-associated fibroblasts (CAF) were the cell type most affected by treatment with canakinumab or gevokizumab in terms of change in gene expression. IL1ß inhibition drove phenotypic changes in CAF populations, particularly those with the ability to influence immune cell recruitment. These results suggest that the observed remodeling of the TME following IL1ß blockade may stem from changes in CAF populations. Overall, the results presented here support the potential use of IL1ß inhibition in cancer treatment. Further exploration in ongoing clinical studies will help identify the best combination partners for different cancer types, cancer stages, and lines of treatment.


Subject(s)
Interleukin-1beta , Neoplasms , Tumor Microenvironment , Animals , Mice , Cell Line, Tumor , Docetaxel/pharmacology , Immunity , Immunotherapy , Neoplasms/drug therapy , Interleukin-1beta/antagonists & inhibitors
12.
Sci Transl Med ; 15(689): eabm8729, 2023 03 29.
Article in English | MEDLINE | ID: mdl-36989374

ABSTRACT

In the context of cancer, clonal hematopoiesis of indeterminate potential (CHIP) is associated with the development of therapy-related myeloid neoplasms and shorter overall survival. Cell-free DNA (cfDNA) sequencing is becoming widely adopted for genomic screening of patients with cancer but has not been used extensively to determine CHIP status because of a requirement for matched blood and tumor sequencing. We present an accurate classification approach to determine the CH status from cfDNA sequencing alone, applying our model to 4324 oncology clinical cfDNA samples. Using this method, we determined that 30.3% of patients in this cohort have evidence of CH, and the incidence of CH varies by tumor type. Matched RNA sequencing data show evidence of increased inflammation, especially neutrophil activation, within the tumors and tumor microenvironments of patients with CH. In addition, patients with CH had evidence of neutrophil activation systemically, pointing to a potential mechanism of action for the worse outcomes associated with CH status. Neutrophil activation may be one of many mechanisms, however, because patients with estrogen receptor-positive breast cancer harboring TET2 frameshift mutations had worse outcomes but similar neutrophil frequencies to patients without CH. Together, these data show the feasibility of detecting CH through cfDNA sequencing alone and an application of this method, demonstrating increased inflammation in patients with CH both systemically and in the tumor microenvironment.


Subject(s)
Cell-Free Nucleic Acids , Neoplasms , Humans , Clonal Hematopoiesis/genetics , Cell-Free Nucleic Acids/genetics , Hematopoiesis/genetics , Neoplasms/pathology , Inflammation , Sequence Analysis, DNA , Mutation/genetics , Tumor Microenvironment
13.
BMC Musculoskelet Disord ; 24(1): 85, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36726086

ABSTRACT

OBJECTIVE: To study the biomechanical characteristics of various tissue structures of different sizes of 3D printed Cage in lumbar interbody fusion. METHODS: A finite element model of normal spine was reconstructed and verified. Pedicle screws and Cage of different sizes were implanted in the L4/5 segment to simulate lumbar interbody fusion. The range of motion of the fixed and cephalic adjacent segment, the stress of the screw-rod system, the stress at the interface between cage and L5 endplate, and intervertebral disc pressure of the adjacent segment were calculated and analyzed. RESULTS: The range of motion and intervertebral disc pressure of the adjacent segment of each postoperative model were larger than those of the intact model, but there was not much difference between them. The stress of cage-endplate interface was also larger than that of the intact model. However, the difference is that the stress of the endplate and the screw-rod system has a tendency to decrease with the increase of the axial area of cage. CONCLUSIONS: Cage with larger axial area in lumbar interbody fusion can reduce the stress of internal fixation system and endplate, but will not increase the range of motion and intervertebral disc pressure of adjacent segment. It has a certain effect in preventing the cage subsidence, internal fixation system failure and screw rod fracture.


Subject(s)
Pedicle Screws , Spinal Fusion , Humans , Finite Element Analysis , Biomechanical Phenomena , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Range of Motion, Articular , Printing, Three-Dimensional
14.
J Environ Manage ; 335: 117514, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36841000

ABSTRACT

Ecological restoration is an important approach to improving landscape sustainability. However, ecological restoration in drylands is strongly limited by water resources. Therefore, a technical route for ecological restoration in drylands that creates sustainable landscapes based on those water constraints is needed. In this study, we develop a spatially explicit framework named "Constraint-Pattern-Benefit" to plan ecological restoration patterns in Inner Mongolia, China. Based on a prediction of the ecosystem service (ES) increase under limited evapotranspiration as a water constraint, we constructed 5 landscape sustainability-related strategies with 100 ecological restoration scenarios, which considered fragmentation of restoration locations, distance to city, water consumption, and the allocation scale to determine the spatial arrangement of ecological restoration. Results show that the ES increase potential of ecological restoration under water constraints is distributed in the center of Inner Mongolia. The multi-objective scenario simultaneously achieves 59.1% water yield, 74.2% soil conservation, 57.2% sand fixation, and 52.8% carbon sequestration with 50% restored landscape. Considering the indicators of fragmentation, water consumption, and distance to city decreases the restored landscape fragmentation from 0.44 to 0.26, improves the restoration efficiency by 14.41%, and increases the beneficiary population by 35.5%, respectively. Small-scale allocation can further increase the ES realization efficiency, which is on average 4.8% higher at the city scale than at the provincial scale. Moreover, this approach focuses on the sustainable effect of the spatial arrangement on dryland landscapes at different scales, which provides methodological support for improving the sustainability of drylands.


Subject(s)
Conservation of Natural Resources , Ecosystem , Water , China , Soil
15.
BMC Musculoskelet Disord ; 23(1): 1122, 2022 Dec 23.
Article in English | MEDLINE | ID: mdl-36550443

ABSTRACT

BACKGROUND: At present, research on spinal shortening is mainly focused on the safe distance of spinal shortening and the mechanism of spinal cord injury, but there is no research on the biomechanical characteristics of different shortening distances. The purpose of this study was to study the biomechanical characteristics of spine and internal fixation instruments at different shortening distances by the finite element (FE) method. METHODS: An FE model of lumbar L1-S was established and referred to the previous in vitro experiments to verify the rationality of the model by verifying the Intradiscal pressure (IDP) and the range of motion (ROM) of the motion segment. Five element models of spinal shortening were designed under the safe distance of spinal shortening, and the entire L3 vertebra and both the upper and lower intervertebral discs were resected. Model A was not shortened, while models B-E were shortened by 10%, 20%, 30% and 50% of the vertebral body, respectively. Constraining the ROM of the sacrum in all directions, a 7.5 N ·m moment and 280 N follower load were applied on the L1 vertebra to simulate the motion of the lumbar vertebrae in three planes. The ROM of the operated segments, the Von Mises stress (VMS) of the screw-rod system, the VMS of the upper endplate at the interface between the titanium cage and the L4 vertebral body, and the ROM and the IDP of the adjacent segment (L5/S) were recorded and analysed. RESULTS: All surgical models showed good stability at the operated segments (L1-5), with the greatest constraint in posterior extension (99.3-99.7%), followed by left-right bending (97.9-98.7%), and the least constraint in left-right rotation (84.9-86.3%) compared with the intact model. The VMS of the screw-rod system and the ROM and IDP of the distal adjacent segments of models A-E showed an increasing trend, in which the VMS of the screw-rod system of model E was the highest under flexion (172.5 MPa). The VMS of the endplate at the interface between the cage and L4 upper endplate of models A-E decreased gradually, and these trend were the most obvious in flexion, which were 3.03, 2.95, 2.83, 2.78, and 2.61 times that of the intact model, respectively. CONCLUSION: When performing total vertebrae resection and correcting the spinal deformity, if the corrected spine has met our needs, the distance of spinal shortening should be minimized to prevent spinal cord injury, fracture of internal fixations and adjacent segment disease (ASD).


Subject(s)
Pedicle Screws , Spinal Fusion , Humans , Finite Element Analysis , Spinal Fusion/methods , Biomechanical Phenomena , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Bone Screws , Range of Motion, Articular
16.
BMC Musculoskelet Disord ; 23(1): 851, 2022 Sep 08.
Article in English | MEDLINE | ID: mdl-36076212

ABSTRACT

OBJECTIVE: To investigate and evaluate the biomechanical behaviour of tension-band-reconstruction (TBR) and ordinary titanium plates in open-door laminoplasty by finite element (FE) analysis. METHODS: TBR titanium plate and ordinary titanium plate were implanted into a validated finite element model of healthy adult cervical vertebrae. Among them, 5 ordinary titanium plate were used in model A, 2 TBR titanium plates and 3 ordinary titanium plates were used in model B, and 5 TBR titanium plates were used in model C. The same loading conditions was applied identically to all models. Range of motion (ROM) of the vertebral body, stress distribution of the titanium plate and intradiscal pressure (IDP) were compared in flexion, extension, lateral bending and rotation. RESULTS: The ROM of model B and C was similar in flexion and extension, and both were smaller than that of model A. The highest von Mises stress in the titanium plate appears is in model C. The IDP in C2/3 was significantly higher than that in other segments in flexion. There was no significant difference in IDP among three models in left lateral bending and left axial rotation. CONCLUSION: Application of TBR titanium plate in open-door laminoplasty can reduced ROM in flexion, extension and axial rotation of the cervical vertebrae. But the increase of stress in TBR titanium plate could lead to higher risk of adverse events such as titanium plate deformation. Moreover, compared with complete TBR titanium plate, the combination of TBR titanium plate for C3 and C7 with ordinary titanium plate for the other vertebrae largely reduce the stress of the titanium plates by ensuring stability. The proposed FE model (C2-T1) exhibits a great potential in evaluating biomechanical behaviour of TBR titanium plate for open-door laminoplasty.


Subject(s)
Laminoplasty , Adult , Humans , Biomechanical Phenomena , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Finite Element Analysis , Laminoplasty/adverse effects , Range of Motion, Articular , Titanium
17.
J Orthop Surg Res ; 17(1): 427, 2022 Sep 24.
Article in English | MEDLINE | ID: mdl-36153558

ABSTRACT

BACKGROUND: Advancements in medicine and the popularity of lumbar fusion surgery have made lumbar adjacent segment disease (ASDz) increasingly common, but there is no mature plan for guiding its surgical treatment. Therefore, in this study, four different finite element (FE) ASDz models were designed and their biomechanical characteristics were analysed to provide a theoretical basis for clinical workers to choose the most appropriate revision scheme for ASDz. METHODS: According to whether internal fixation was retained, different FE models were created to simulate ASDz revision surgery, and flexion, extension, axial rotation and lateral bending were simulated by loading. The biomechanical characteristics of the adjacent segments of the intervertebral disc and the internal fixation system and the range of motion (ROM) of the lumbar vertebrae were analysed. RESULTS: The difference in the ROM of the fixed segment between FE models that did or did not retain the original internal fixation was less than 0.1°, and the difference was not significant. However, the stress of the screw-rod system when the original internal fixation was retained and prolonged fixation was performed with dual-trajectory screws was less than that when the original internal fixation was removed and prolonged fixation was performed with a long bar. Especially in axial rotation, the difference between models A and B is the largest, and the difference in peak stress reached 30 MPa. However, for the ASDz revision surgery segment, the endplate stress between the two models was the lowest, and the intradiscal pressure (IDP) of the adjacent segment was not significantly different between different models. CONCLUSION: Although ASDz revision surgery by retaining the original internal fixation and prolonging fixation with dual-trajectory screws led to an increase in stress in the fusion segment endplate, it provides stability similar to ASDz revision surgery by removing the original internal fixation and prolonging fixation with a long bar and does not lead to a significant change in the IDP of the adjacent segment while avoiding a greater risk of rod fracture.


Subject(s)
Pedicle Screws , Spinal Fusion , Humans , Biomechanical Phenomena , Finite Element Analysis , Lumbar Vertebrae/surgery , Range of Motion, Articular , Reoperation
18.
Environ Pollut ; 311: 119982, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-35988675

ABSTRACT

For the first time, we used targeted metabolome to investigate the effects of pH-aluminum (Al) interactions on energy-rich compounds and their metabolites (ECMs) and phytohormones in sweet orange (Citrus sinensis) roots. The concentration of total ECMs (TECMs) was reduced by Al-toxicity in 4.0-treated roots, but unaffected significantly in pH 3.0-treated roots. However, the concentrations of most ECMs and TECMs were not lower in pH 4.0 + 1.0 mM Al-treated roots (P4AR) than in pH 3.0 + 1.0 mM Al-treated roots (P3AR). Increased pH improved the adaptability of ECMs to Al-toxicity in roots. For example, increased pH improved the utilization efficiency of ECMs and the conversion of organic phosphorus (P) from P-containing ECMs into available phosphate in Al-treated roots. We identified upregulated cytokinins (CKs), downregulated jasmonic acid (JA), methyl jasmonate (MEJA) and jasmonates (JAs), and unaltered indole-3-acetic acid (IAA) and salicylic acid (SA) in P3AR vs pH 3.0 + 0 mM Al-treated roots (P3R); upregulated JA, JAs and IAA, downregulated total CKs, and unaltered MEJA and SA in P4AR vs pH 4.0 + 0 mM Al-treated roots (P4R); and upregulated CKs, downregulated JA, MEJA, JAs and SA, and unaltered IAA in P3AR vs P4AR. Generally viewed, raised pH-mediated increments of JA, MEJA, total JAs, SA and IAA concentrations and reduction of CKs concentration in Al-treated roots might help to maintain nutrient homeostasis, increase Al-toxicity-induced exudation of organic acid anions and the compartmentation of Al in vacuole, and reduce oxidative stress and Al uptake, thereby conferring root Al-tolerance. In short, elevated pH-mediated mitigation of root Al-stress involved the regulation of ECMs and phytohormones.


Subject(s)
Citrus sinensis , Citrus , Aluminum/metabolism , Aluminum/toxicity , Citrus sinensis/metabolism , Hydrogen-Ion Concentration , Plant Growth Regulators/metabolism , Plant Growth Regulators/pharmacology , Plant Roots/metabolism
19.
Cell Mol Biol (Noisy-le-grand) ; 67(6): 281-290, 2022 Feb 27.
Article in English | MEDLINE | ID: mdl-35818185

ABSTRACT

Polyphenols and flavonoids are phytochemicals that have essential roles in human nutrition. In this regard, the contents of polyphenols and flavonoids in Houttuynia cordata Thunb and their antioxidant activities were evaluated in the current study. Two Houttuynia cordata materials with the same chromosome number and chemical type were used to comprehensively assess the contents of total phenols and flavonoids in different parts of H. cordata. These chemical components were extracted by the ultrasonic method. The results showed that the total phenols and antioxidant capacity of different parts of H. cordata were significantly different. The content of polyphenols in roots and stems was low, the antioxidant capacity was weak, the total phenols in flowers and leaves were high, and the antioxidant capacity was strong. Therefore, different parts of H. cordata had different pharmacological and food effects. The whole herb can be used as Chinese herbal medicine, and its young leaves and roots can be used as vegetables. Flavonoids are the main phenolic components, and total phenols are the main components of antioxidant activity. It can explain a very significant positive correlation between total phenols and flavonoids. Therefore, in the further breeding work of H. cordata, the procedure can be simplified by determining one of the above indexes to predict the varieties with high total phenolic and antioxidant activity.


Subject(s)
Houttuynia , Antioxidants/pharmacology , Flavonoids/pharmacology , Houttuynia/chemistry , Humans , Phenols/pharmacology , Polyphenols , Ultrasonics
20.
J Biomed Mater Res A ; 110(10): 1645-1654, 2022 10.
Article in English | MEDLINE | ID: mdl-35676876

ABSTRACT

Soft tissue integration surrounding dental implant is considered as a biological barrier against the oral microorganisms and external stimuli. At present, successful soft tissues integration around implants remains a challenge. The aim of this study was to evaluate the effects of nanostructured zirconia abutment surfaces on fibroblasts viability and Porphyromonas gingivalis adhesion, which are the two main factors influencing the quality of peri-implant soft-tissue seal. Zirconia samples were made from three-dimensional gel deposition approach and divided into three groups: zirconia surfaces, zirconia film coated surfaces (CZr) and polished surfaces (PZr). The Surface properties were characterized by scanning electron microscopy, atomic force microscopy and water contact angle. The behavior of human gingival fibroblasts (HGFs) on samples, including of proliferation, morphology, gene expression and protein expression as well as collagen synthesis were assessed. Additionally, the adhesion of P. gingivalis on samples was analyzed by scanning electron microscopy and live/dead staining. CZr and PZr group significantly enhanced fibroblasts viability such as cell proliferation, cell spreading and extracellular matrix secretion, and impaired P. gingivalis adhesion. Therefore, our findings demonstrated that CZr and PZr surfaces with nano-grains or grinding grooves might be considered as the feasible zirconia abutments substrate for reinforcing HGFs response and minimizing P. gingivalis adhesion, and thereby enhance peri-implant soft-tissue integration.


Subject(s)
Dental Implants , Porphyromonas gingivalis , Cell Adhesion , Fibroblasts , Gingiva , Humans , Surface Properties , Titanium/chemistry , Zirconium/chemistry , Zirconium/pharmacology
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