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1.
Spine J ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38754736

RESUMO

BACKGROUND CONTEXT: Cage subsidence is a common complication after lumbar interbody fusion surgery, with low bone mineral density (BMD) being a significant risk factor. ໿Endplate bone quality (EBQ) obtained from clinical MRI scans has been deemed reliable in determining regional BMD. However, the association between EBQ score and cage subsidence following oblique lumbar interbody fusion (OLIF) has not been clearly established. PURPOSE: This study aims to assess the relationship between EBQ score and cage subsidence in patients who underwent single-level OLIF. STUDY DESIGN/SETTING: A retrospective study. PATIENT SAMPLE: The study included adults with degenerative spinal conditions who underwent single-level OLIF at our institution OUTCOME MEASURES: Cage subsidence, disc height, EBQ score, fusion rate. METHODS: This retrospective study analyzed data from patients who underwent single-level OLIF surgery at our institution between October 2017 and August 2022. Postoperative CT scans were used to measure cage subsidence, while the EBQ score was calculated using preoperative non-contrast T1-weighted MRI. To determine the predictive ability of the EBQ score, receiver operating characteristic (ROC) curve analysis was conducted. Additionally, univariable and multivariable logistic regression analyses were performed. RESULTS: In this study, a total of 88 patients were included and followed up for an average of 15.8 months. It was observed that 32.9% (n=29/88) of the patients experienced cage subsidence. The post-surgery disc height was significantly higher in patients who experienced subsidence compared to those who did not. The mean EBQ scores for patients with non-subsidence and subsidence were 2.31±0.6 and 3.48±1.2, respectively, and this difference was statistically significant. The ROC curve analysis showed that the AUC for the EBQ score was 0.811 (95% CI: 0.717-0.905). The most suitable threshold for the EBQ score was determined to be 2.318 (sensitivity: 93.1%, specificity: 55.9%). Additionally, the multivariate logistic regression analysis revealed a significant association between a higher EBQ score and an increased risk of subsidence (odds ratio [OR]=6.204, 95% CI=2.520-15.272, p<.001). CONSLUSIONS: Our findings indicate that higher preoperative EBQ scores are significantly linked to cage subsidence following single-level OLIF. Preoperative measurement of MRI can serve as a valuable tool in predicting cage subsidence.

2.
J Neurosurg Spine ; : 1-11, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728766

RESUMO

OBJECTIVE: The role of interbodies in lumbar arthrodesis has been insufficiently supported by evidence, impacting clinical decision-making and occasionally insurance coverage. This study aimed to compare clinical and radiological outcomes between lumbar arthrodesis with a synthetic interbody spacer (cage) versus structural bone graft alone (autograft or allograft) in patients with degenerative spine disease. METHODS: A systematic review of the literature was performed to identify studies directly comparing outcomes of lumbar interbody arthrodesis with and without interbody cage use. The outcomes of individual studies were synthesized in meta-analyses using random-effects models. RESULTS: Twenty studies with 1508 patients (769 with an interbody cage and 739 without an interbody cage) were included. Interbody cage placement was associated with a significantly greater increase in disc height after surgery (4.0 mm vs 3.4 mm, p < 0.01). There was a significantly greater reduction of back pain (visual analog scale [VAS] score) in cases in which an interbody cage was used (5.4 vs 4.7, p = 0.03). Fusion rates were 5.5% higher in the cage group (96.3% vs 90.8%) and reached statistical significance (p = 0.03). No statistically significant differences were identified between the two groups regarding all-cause reoperation rates, complication rates, or improvement in Oswestry Disability Index score or leg pain (VAS score). CONCLUSIONS: These results suggest that implantation of an interbody cage is associated with higher rates of fusion, more effective maintenance of disc height, and greater improvement of back pain. This study underlines the clinical value of interbody cages in lumbar arthrodesis for patients with degenerative spine disease.

3.
Front Immunol ; 15: 1374437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711507

RESUMO

Mycobacterium avium complex (MAC) is a non-tuberculous mycobacterium widely distributed in the environment. Even though MAC infection is increasing in older women and immunocompromised patients, to our knowledge there has been no comprehensive analysis of the MAC-infected host-cell transcriptome-and particularly of long non-coding RNAs (lncRNAs). By using in vitro-cultured primary mouse bone-marrow-derived macrophages (BMDMs) and Cap analysis of gene expression, we analyzed the transcriptional and kinetic landscape of macrophage genes, with a focus on lncRNAs, during MAC infection. MAC infection of macrophages induced the expression of immune/inflammatory response genes and other genes similar to those involved in M1 macrophage activation, consistent with previous reports, although Nos2 (M1 activation) and Arg1 (M2 activation) had distinct expression profiles. We identified 31 upregulated and 30 downregulated lncRNA promoters corresponding respectively to 18 and 26 lncRNAs. Upregulated lncRNAs were clustered into two groups-early and late upregulated-predicted to be associated with immune activation and the immune response to infection, respectively. Furthermore, an Ingenuity Pathway Analysis revealed canonical pathways and upstream transcription regulators associated with differentially expressed lncRNAs. Several differentially expressed lncRNAs reported elsewhere underwent expressional changes upon M1 or M2 preactivation and subsequent MAC infection. Finally, we showed that expressional change of lncRNAs in MAC-infected BMDMs was mediated by toll-like receptor 2, although there may be other mechanisms that sense MAC infection. We identified differentially expressed lncRNAs in MAC-infected BMDMs, revealing diverse features that imply the distinct roles of these lncRNAs in MAC infection and macrophage polarization.


Assuntos
Perfilação da Expressão Gênica , Macrófagos , Complexo Mycobacterium avium , Infecção por Mycobacterium avium-intracellulare , RNA Longo não Codificante , Transcriptoma , RNA Longo não Codificante/genética , Animais , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/metabolismo , Complexo Mycobacterium avium/imunologia , Complexo Mycobacterium avium/genética , Camundongos , Infecção por Mycobacterium avium-intracellulare/imunologia , Infecção por Mycobacterium avium-intracellulare/genética , Infecção por Mycobacterium avium-intracellulare/microbiologia , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Células Cultivadas , Regulação da Expressão Gênica
4.
Angew Chem Int Ed Engl ; : e202407034, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708741

RESUMO

Chirality, a fundamental principle in chemistry, biology, and medicine, is prevalent in nature and in organisms. Chiral molecules, such as DNA, RNA, and proteins, are crucial in biomolecular synthesis, as well as in the development of functional materials. Among these, 1,1´-binaphthyl-2,2´-diol (BINOL) stands out for its stable chiral configuration, versatile functionality, and commercial availability. BINOL is widely employed in asymmetric catalysis and chiral materials. This review mainly focuses on recent research over the past five years concerning the use of BINOL derivatives for constructing chiral macrocycles and cages. Their contributions to chiral luminescence, enantiomeric separation, transmembrane transport, and asymmetric catalysis were examined.

5.
Proc Natl Acad Sci U S A ; 121(20): e2321260121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38722807

RESUMO

Protein capsids are a widespread form of compartmentalization in nature. Icosahedral symmetry is ubiquitous in capsids derived from spherical viruses, as this geometry maximizes the internal volume that can be enclosed within. Despite the strong preference for icosahedral symmetry, we show that simple point mutations in a virus-like capsid can drive the assembly of unique symmetry-reduced structures. Starting with the encapsulin from Myxococcus xanthus, a 180-mer bacterial capsid that adopts the well-studied viral HK97 fold, we use mass photometry and native charge detection mass spectrometry to identify a triple histidine point mutant that forms smaller dimorphic assemblies. Using cryoelectron microscopy, we determine the structures of a precedented 60-mer icosahedral assembly and an unexpected 36-mer tetrahedron that features significant geometric rearrangements around a new interaction surface between capsid protomers. We subsequently find that the tetrahedral assembly can be generated by triple-point mutation to various amino acids and that even a single histidine point mutation is sufficient to form tetrahedra. These findings represent a unique example of tetrahedral geometry when surveying all characterized encapsulins, HK97-like capsids, or indeed any virus-derived capsids reported in the Protein Data Bank, revealing the surprising plasticity of capsid self-assembly that can be accessed through minimal changes in the protein sequence.


Assuntos
Proteínas do Capsídeo , Capsídeo , Microscopia Crioeletrônica , Mutação Puntual , Capsídeo/metabolismo , Capsídeo/química , Capsídeo/ultraestrutura , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Myxococcus xanthus/genética , Myxococcus xanthus/metabolismo , Modelos Moleculares
6.
Saudi J Biol Sci ; 31(7): 104007, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38778840

RESUMO

This research aims to assess the production and oxidative stress reactions of lambs fed in a specially designed cage for creep feeding. For this purpose, the Akkaraman lambs (n = 60) were separated into four groups (15 individuals by two sexes and two groups), and all were fed the same ration. On the days that all the data was collected, the lambs were precisely 20, 34, 48, and 62 days old. The study included collecting data on body weights, body measures, and saliva samples from lambs. When the change in body weight was investigated, the results indicated that the differences between caged creep and control feeding groups (P = 0.343) and among the groupings concerning gender (P = 0.735) were insignificant. The importance levels of change differences in body measurements based on feeding methods and gender are withers height: P = 0.003, P = 0.198; body length: P < 0.001, P = 0.394; pectoral chest width: P = 0.030, P = 0.906; chest depth: P < 0.001, P = 0.741; chest circumference: P = 0.093, P = 0.529; back length: P = 0.221, P = 0.935; head length: P = 0.004, P = 0.072 and head width: P = 0.112, P = 0.617 calculated. The study's saliva samples, the effects were examined, and significant differences in Malondialdehyde (P = 0.014), superoxide dismutase (P = 0.029), catalase (P < 0.001), and glutathione s-transferase (P = 0.001) were discovered between control feeding and caged creep feeding methods. In ischemia-modified albumin (P > 0.05), the difference between the groups was insignificant. According to these findings, caged creep feeding systems are preferable for achieving faster growth rates in Akkaraman lambs; however, caged creep feeding techniques in bigger areas with longer periods are considered better for welfare conditions.

7.
ISA Trans ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38777694

RESUMO

This article presents a robust finite control set predictive scheme for a stand-alone squirrel cage induction generator (SCIG) drive. This technique is considered an alternative to the drive system due to the inclusion of system nonlinearities and fast dynamic response. The control objective in the distributed generation environment is to fix the output voltage to follow the stand-alone requirement. The strategy establishes optimized switching instants for cost function minimization for both source and load converter control and diminished cross-coupling amid active and reactive power during transient scenarios. The scheme is designed to achieve the minimal effect caused by the parameter uncertainties. During source and load changes, this work will also address the maintenance of dc-link voltage, machine, and load variables at the set value, supported by machine and load-end converter control to achieve stand-alone load objectives. In addition, the presented scheme is also tested with random variation of speed to check the efficacy of the control configuration. The drive performance is evaluated by simulation using MATLAB/Simulink environment. Comprehensive real-time findings obtained from a scaled laboratory test bench using dSPACE-1104 are provided to verify the feasibility of the predictive solution.

8.
Global Spine J ; : 21925682241253168, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780086

RESUMO

STUDY DESIGN: Retrospective Study. OBJECTIVES: To compare subsidence and radiographic fusion rates of titanium-surface polyetheretherketone (PEEK-Ti) and 3D-Titanium (3D-Ti) cages, implanted within the same patient concurrently, during multi-level transforaminal lumbar interbody fusions (TLIF). METHODS: Forty-eight patients were treated with both PEEK-Ti and 3D-Ti cages during 2- or 3-level TLIF and instrumented posterolateral fusion (108 spinal levels in all). Equivalent bone graft material was implanted within each patient. Radiographic analysis of CT and/or X-ray imaging was performed retrospectively for each spinal level throughout 12-month follow-up period. Fusion was defined as bridging trabecular bone and subsidence was incursion into one/both vertebral bodies >20% cage height. Outcomes were analyzed with Fisher's exact test. RESULTS: At 6-months post-operative follow-up, incidence of subsidence was significantly lower for PEEK-Ti cages, with 4.8% subsidence, compared to a 27.9% subsidence rate for 3D-Ti cages (P = .007). Fusion rates were comparable at 100% for PEEK-Ti and 95.5% for 3D-Ti. Results at 12-months showed similar but not statistically significant trends of less subsidence with PEEK-Ti than 3D-Ti cages (14.3% PEEK-Ti, 37.5% 3D-Ti), and similar fusion rates of 100% for PEEK-Ti and 91.7% for 3D-Ti. Thirty-nine out of 48 total patients were available for follow-up at 6 months and 20 patients at 12 months. CT availability at 6 and 12-months was 100% and 90%, respectively. CONCLUSIONS: A significantly lower subsidence rate was associated with a PEEK-Ti cage, compared to 3D-Ti, 6 months after TLIF. Results may not be generalized across technologies due to differences in cage designs; additional research studies are warranted.

9.
J Biol Inorg Chem ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780762

RESUMO

Ferritins are multimeric nanocage proteins that sequester/concentrate excess of free iron and catalytically synthesize a hydrated ferric oxyhydroxide bio-mineral. Besides functioning as the primary intracellular iron storehouses, these supramolecular assemblies also oversee the controlled release of iron to meet physiologic demands. By virtue of the reducing nature of the cytosol, reductive dissolution of ferritin-iron bio-mineral by physiologic reducing agents might be a probable pathway operating in vivo. Herein, to explore this reductive iron-release pathway, a series of quinone analogs differing in size, position/nature of substituents and redox potentials were employed to relay electrons from physiologic reducing agent, NADH, to the ferritin core. Quinones are well known natural electron/proton mediators capable of facilitating both 1/2 electron transfer processes and have been implicated in iron/nutrient acquisition in plants and energy transduction. Our findings on the structure-reactivity of quinone mediators highlight that iron release from ferritin is dictated by electron-relay capability (dependent on E1/2 values) of quinones, their molecular structure (i.e., the presence of iron-chelation sites and the propensity for H-bonding) and the type/amount of reactive oxygen species (ROS) they generate in situ. Juglone/Plumbagin released maximum iron due to their intermediate E1/2 values, presence of iron chelation sites, the ability to inhibit in situ generation of H2O2 and form intramolecular H-bonding (possibly promotes semiquinone formation). This study may strengthen our understanding of the ferritin-iron-release process and their significance in bioenergetics/O2-based cellular metabolism/toxicity while providing insights on microbial/plant iron acquisition and the dynamic host-pathogen interactions.

10.
Angew Chem Int Ed Engl ; : e202406564, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766872

RESUMO

How to achieve CO2 electroreduction in high efficiency is a current challenge with the mechanism not well understood yet. The metal-organic cages with multiple metal sites, tunable active centers, and well-defined microenvironments may provide a promising catalyst model. Here, we report self-assembly of Ag4L4 type cuboctahedral cages from coordination dynamic Ag+ ion and triangular imidazolyl ligand 1,3,5-tris(1-benzylbenzimidazol-2-yl) benzene (Ag-MOC-X, X= NO3, ClO4, BF4) via anion template effect. Notably, Ag-MOC-NO3 achieves the highest CO faradaic efficiency in pH-universal electrolytes of 86.1%(acidic), 94.1%(neutral) and 95.3% (alkaline), much higher than those of Ag-MOC-ClO4 and Ag-MOC-BF4 with just different counter anions. In situ attenuated total reflection Fourier transform infrared spectroscopy observes formation of vital intermediate *COOH for CO2-to-CO conversion. The density functional theory calculations suggest that the adsorption of CO2 on unsaturated Ag-site is stabilized by C-H⋅⋅⋅O hydrogen-bonding of CO2 in a microenvironment surrounded by three benzimidazole rings, and the activation of CO2 is dependent on the coordination dynamics of Ag-centers modulated by the hosted anions through Ag⋅⋅⋅X interactions. This work offers a supramolecular electrocatalytic strategy based on Ag-coordination geometry and host-guest interaction regulation of MOCs as high-efficient electrocatalysts for CO2 reduction to CO which is a key intermediate in chemical industry process.

11.
Brain Behav ; 14(5): e3482, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38715397

RESUMO

INTRODUCTION: Chronic adolescent stress profoundly affects prefrontal cortical networks regulating top-down behavior control. However, the neurobiological pathways contributing to stress-induced alterations in the brain and behavior remain largely unknown. Chronic stress influences brain growth factors and immune responses, which may, in turn, disrupt the maturation and function of prefrontal cortical networks. The tumor necrosis factor alpha-converting enzyme/a disintegrin and metalloproteinase 17 (TACE/ADAM17) is a sheddase with essential functions in brain maturation, behavior, and inflammatory responses. This study aimed to determine the impact of stress on the prefrontal cortex and whether TACE/ADAM17 plays a role in these responses. METHODS: We used a Lewis rat model that incorporates critical elements of chronic psychosocial stress, such as uncontrollability, unpredictability, lack of social support, and re-experiencing of trauma. RESULTS: Chronic stress during adolescence reduced the acoustic startle reflex and social interactions while increasing extracellular free water content and TACE/ADAM17 mRNA levels in the medial prefrontal cortex. Chronic stress altered various ethological behavioral domains in the observation home cages (decreased ingestive behaviors and increased walking, grooming, and rearing behaviors). A group of rats was injected intracerebrally either with a novel Accell™ SMARTpool TACE/ADAM17 siRNA or a corresponding siRNA vehicle (control). The RNAscope Multiplex Fluorescent v2 Assay was used to visualize mRNA expression. Automated puncta quantification and analyses demonstrated that TACE/ADAM17 siRNA administration reduced TACE/ADAM17 mRNA levels in the medial prefrontal cortex (59% reduction relative to control). We found that the rats that received prefrontal cortical TACE/ADAM17 siRNA administration exhibited altered eating patterns (e.g., increased food intake and time in the feeding zone during the light cycle). CONCLUSION: This study supports that the prefrontal cortex is sensitive to adolescent chronic stress and suggests that TACE/ADAM17 may be involved in the brain responses to stress.


Assuntos
Proteína ADAM17 , Córtex Pré-Frontal , Ratos Endogâmicos Lew , Estresse Psicológico , Animais , Masculino , Ratos , Proteína ADAM17/metabolismo , Comportamento Animal/fisiologia , Córtex Pré-Frontal/metabolismo , Reflexo de Sobressalto/fisiologia , Estresse Psicológico/fisiopatologia , Estresse Psicológico/metabolismo , Feminino
12.
J Neurosurg Spine ; : 1-8, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38759244

RESUMO

OBJECTIVE: The aim of this study was to investigate the predictive value of different site-specific MRI-based assessments of bone quality for cage subsidence among patients undergoing oblique lumbar interbody fusion (OLIF) with or without posterior internal fixation. METHODS: The authors retrospectively reviewed the records of patients who underwent OLIF between 2017 and 2022. Endplate bone quality (EBQ), mean vertebral bone quality (MVBQ), and vertebral bone quality (VBQ) scores were measured using preoperative non-contrast-enhanced T1-weighted MRI of the lumbar spine. Logistic regression analysis was used to identify factors associated with cage subsidence. Receiver operating characteristic curve analysis was used to evaluate the value of different site-specific MRI-based assessments of bone quality in predicting cage subsidence. RESULTS: Of the 124 patients who underwent OLIF, subsidence was found in 42 (33.9%). The VBQ, MVBQ, and EBQ scores were higher in the subsidence group than in the no-subsidence group. In the stand-alone OLIF (SA-OLIF) group, logistic regression analysis showed that the EBQ score was significantly associated with subsidence (OR 13.656, 95% CI 2.561-72.806; p = 0.002). Furthermore, the areas under the curve (AUCs) for using the VBQ, MVBQ, and EBQ scores and T-score to predict cage subsidence were 0.684, 0.683, 0.745, and 0.685, respectively. In the OLIF with posterior internal fixation (OLIF-PF) group, logistic regression analysis showed that the MVBQ score was significantly associated with subsidence (OR 8.301, 95% CI 2.064-33.385; p = 0.003). The AUCs for using the VBQ score, MVBQ score, and T-score to predict cage subsidence were 0.757, 0.774, and 0.685, respectively. CONCLUSIONS: There are significant differences in the predictive value of different site-specific bone quality assessments for cage subsidence among patients undergoing OLIF. For SA-OLIF, the EBQ score is recommended, while for OLIF-PF, the VBQ score is preferable.

13.
Angew Chem Int Ed Engl ; : e202408056, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758007

RESUMO

Here, we successfully synthesized four structurally analogous, self-assembled chiral molecular tubes with relatively high yields. This achievement involved the condensation of six equivalents of enantiomerically pure trans-cyclohexane-1,2-diamine (trans-CHDA) and three equivalents of the corresponding tetraformyl precursor. Each precursor was equipped with a luminescent linker terminated by two m-phthalaldehyde units. Even though these tetraformyl precursors are barely soluble in almost all organic solvents, the molecular tubes are highly soluble in nonpolar solvents such as chloroform, allowing us to fully characterize them in solution. The stereo-chirality of the chiral bisamino building blocks endows the frameworks of molecular tubes with planar chirality. As a consequence, all of these molecular tubes exhibit circularly polarized luminescence (CPL) with relatively large dissymmetry values |glum| up to 7 × 10-3, providing an efficient method for synthesizing CPL-active materials.

14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(5): 535-541, 2024 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-38752238

RESUMO

Objective: To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the posterior longitudinal ligament (OPLL). Methods: A retrospective analysis was conducted on clinical data from 45 patients with cervical OPLL admitted between September 2019 and August 2021 and meeting the selection criteria. All patients underwent anterior cervical corpectomy and decompression, interbody bone graft fusion, and titanium plate internal fixation. During operation, 21 patients in the study group received titanium alloy trabecular bone 3D printed artificial vertebral bodies, while 24 patients in the control group received titanium cages. There was no significant difference in baseline data such as gender, age, disease duration, affected segments, or preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), vertebral height, and C 2-7Cobb angle ( P>0.05). Operation time, intraoperative blood loss, and occurrence of complications were recorded for both groups. Preoperatively and at 3 and 12 months postoperatively, the functionality and symptom relief were assessed using JOA scores, VAS scores, and NDI evaluations. The vertebral height and C 2-7 Cobb angle were detected by imaging examinations and the implant subsidence and intervertebral fusion were observed. Results: The operation time and incidence of complications were significantly lower in the study group than in the control group ( P<0.05), while the difference in intraoperative blood loss between the two groups was not significant ( P>0.05). All patients were followed up 12-18 months, with the follow-up time of (14.28±4.34) months in the study group and (15.23±3.54) months in the control group, showing no significant difference ( t=0.809, P=0.423). The JOA score, VAS score, and NDI of the two groups improved after operation, and further improved at 12 months compared to 3 months, with significant differences ( P<0.05). At each time point, the study group exhibited significantly higher JOA scores and improvement rate compared to the control group ( P<0.05); but there was no significantly difference in VAS score and NDI between the two groups ( P>0.05). Imaging re-examination showed that the vertebral height and C 2-7Cobb angle of the two groups significantly increased at 3 and 12 months after operation ( P<0.05), and there was no significant difference between 3 and 12 months after operation ( P>0.05). At each time point, the vertebral height and C 2-7Cobb angle of the study group were significantly higher than those of the control group ( P<0.05), and the implant subsidence rate was significantly lower than that of the control group ( P<0.05). However, there was no significant difference in intervertebral fusion rate between the two groups ( P>0.05). Conclusion: Compared to traditional titanium cages, the use of titanium alloy trabecular bone 3D-printed artificial vertebral bodies for treating cervical OPLL results in shorter operative time, fewer postoperative complications, and lower implant subsidence rates, making it superior in vertebral reconstruction.


Assuntos
Ligas , Vértebras Cervicais , Ossificação do Ligamento Longitudinal Posterior , Impressão Tridimensional , Fusão Vertebral , Titânio , Humanos , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Vértebras Cervicais/cirurgia , Estudos Retrospectivos , Fusão Vertebral/métodos , Fusão Vertebral/instrumentação , Descompressão Cirúrgica/métodos , Osso Esponjoso , Resultado do Tratamento , Corpo Vertebral/cirurgia , Feminino , Masculino , Placas Ósseas , Pessoa de Meia-Idade
15.
Eur Spine J ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733400

RESUMO

PURPOSE: To analyze the effect of endplate weakness prior to PLIF or TLIF cage implantation and compare it to the opposite intact endplate of the same vertebral body. In addition, the influence of bone quality on endplate resistance was investigated. METHODS: Twenty-two human lumbar vertebrae were tested in a ramp-to-failure test. One endplate of each vertebral body was tested intact and the other after weakening with a rasp (over an area of 200 mm2). Either a TLIF or PLIF cage was then placed and the compression load was applied across the cage until failure of the endplate. Failure was defined as the first local maximum of the force measurement. Bone quality was assessed by determining the Hounsfield units (HU) on CT images. RESULTS: With an intact endplate and a TLIF cage, the median force to failure was 1276.3N (693.1-1980.6N). Endplate weakening reduced axial endplate resistance to failure by 15% (0-23%). With an intact endplate and a PLIF cage, the median force to failure was 1057.2N (701.2-1735.5N). Endplate weakening reduced axial endplate resistance to failure by 36.6% (7-47.9%). Bone quality correlated linearly with the force at which endplate failure occurred. Intact and weakened endplates showed a strong positive correlation: intact-TLIF: r = 0.964, slope of the regression line (slope) = 11.8, p < 0.001; intact-PLIF: r = 0.909, slope = 11.2, p = 5.5E-05; weakened-TLIF: r = 0.973, slope = 12.5, p < 0.001; weakened-PLIF: r = 0.836, slope = 6, p = 0.003. CONCLUSION: Weakening of the endplate during cage bed preparation significantly reduces the resistance of the endplate to subsidence to failure: endplate load capacity is reduced by 15% with TLIF and 37% with PLIF. Bone quality correlates with the force at which endplate failure occurs.

16.
Neurotoxicol Teratol ; 103: 107356, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38719082

RESUMO

Developmental stress, including low socioeconomic status (SES), can induce dysregulation of the hypothalamic-pituitary-adrenal axis and result in long-term changes in stress reactivity. Children in lower SES conditions often experience more stress than those in other SES groups. There are multiple model systems of early environmental stress (EES), one of which is reduced cage bedding. Here we tested the effects of both prenatal and lactational EES in rats on a range of long-term behavioral and cognitive outcomes. There were persistent reductions in body weight in the EES rats in both sexes. The behavioral results showed no effects on learning and memory using tests of spatial learning or cognitive flexibility in the Morris water maze, egocentric learning in the Cincinnati water maze, or working memory in the radial-arm maze. There were no effects on basic open-field activity, elevated zero-maze, or forced swim test, but EES rats had reduced time in the dark side of the light/dark test. When rats were drug challenged in the open-field with d-amphetamine or MK-801, there were no differential responses to d-amphetamine, but the EES group under responded compared with the drug-induced hyperactivity in the control group in both males and females. The objective was to establish a developmental stress model that induced cognitive deficits and to the extent that this method did not cause such effects it was not the model we sought. However, the data showed several long-term effects of EES, including the reduced response to the irreversible NMDA antagonist MK-801. This effect merits further investigation.

17.
Toxics ; 12(5)2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38787138

RESUMO

Bisphenol A (BPA), representing a class of organic pollutants, finds extensive applications in the pharmaceutical industry. However, its widespread use poses a significant hazard to both ecosystem integrity and human health. Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS) via heterogeneous catalysts are frequently proposed for treating persistent pollutants. In this study, the degradation performance of BPA in an oxidation system of PMS activated by transition metal sites anchored nitrogen-doped carbonaceous substrate (M-N-C) materials was investigated. As heterogeneous catalysts targeting the activation of peroxymonosulfate (PMS), M-N-C materials emerge as promising contenders poised to overcome the limitations encountered with traditional carbon materials, which often exhibit insufficient activity in the PMS activation process. Nevertheless, the amalgamation of metal sites during the synthesis process presents a formidable challenge to the structural design of M-N-C. Herein, employing ZIF-8 as the precursor of carbonaceous support, metal ions can readily penetrate the cage structure of the substrate, and the N-rich linkers serve as effective ligands for anchoring metal cations, thereby overcoming the awkward limitation. The research results of this study indicate BPA in water matrix can be effectively removed in the M-N-C/PMS system, in which the obtained nitrogen-rich ZIF-8-derived Cu-N-C presented excellent activity and stability on the PMS activation, as well as the outstanding resistance towards the variation of environmental factors. Moreover, the biological toxicity of BPA and its degradation intermediates were investigated via the Toxicity Estimation Software Tool (T.E.S.T.) based on the ECOSAR system.

18.
Chemistry ; : e202401013, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700019

RESUMO

The dynamic interplay of coordination bonds within metal-organic cages offers a unique avenue for structural evolution in response to external stimuli, presenting a promising strategy for the construction of chiral assemblies. This adaptability is crucial for the selective synthesis of homochiral assemblies and advancement of asymmetric catalysis. In this study, we report the self-assembly of an achiral square-planar Pd(II) acceptor with a C2-symmetric tetrapyridyl donor resulted in the formation of a racemic mixture of the chiral octahedral cage Pd4L2. The existence of this racemic mixture was confirmed using circular dichroism spectroscopy as well as single crystal X-ray diffraction analysis. We encoded chiral information into the asymmetric cavity of the cage by encapsulating chiral aromatic guests through efficient π-π stacking and hydrophobic interactions in aqueous media. The inclusion of a chiral guest induces a preference for one enantiomeric conformation of the cage over the other, effectively shifting the equilibrium towards a single, enantiopure host-guest complex. While the concept of chiral guest recognition by a chiral host is well-established, this work constitutes a remarkable example of guest-mediated chirality transfer leading to the formation of a single enantiopure coordination complex from achiral building blocks.

19.
World Neurosurg ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38679377

RESUMO

BACKGROUND: Anterior cervical corpectomy and fusion achieves foraminal radicular and central medullary decompression and spinal stabilization in staged lesions. Many bone graft materials have been developed for the reconstruction of cervical lordosis and the restoration of intervertebral height after corpectomy. The PolyEtherKetoneEtherKetoneKetone (PEKEKK) is a semicrystalline thermoplastic polymer that can be reinforced with carbon fibers to create long and highly fenestrated rectangular cervical cages for corpectomy. This study aimed to evaluate the radiological outcomes of an innovative PEKEEKK cage compared with others grafting options. METHODS: Forty-five consecutive patients who underwent surgery with PEKEKK cages between 2017 and 2019 at a spine institution, were matched with 15 patients with a titanium mesh cylindrical cage (TMC) and 15 patients with a tricortical structural iliac bone graft. The restoration of vertebral height and cervical lordosis postoperatively, and subsidence of the construct were evaluated. Complications were reported. RESULTS: The minimal follow-up was 5.1±2years. A better, but nonsignificant, postoperative gain in height was observed for PEKEKK (+8.1 ± 20%) and TMC cages (+8.2 ± 16%) than for iliac crest autograft reconstruction (+2.3 ± 15%, P = 0.119). The mean subsidence at the last follow-up was greater for TMC cages (-10.2 ± 13%), but was not significant, with -6.1 ± 10% for PEKEKK cages and -4.1 ± 7% for iliac crest autografts (P = 0.223). The gain in segmental cervical lordosis was significant (P < 0.001) and remained stable in all the groups. CONCLUSIONS: Although an improvement in radiologic anatomical parameters can be achieved with all cage groups, the PEKEKK cage can be considered as a safe alternative for reducing subsidence.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38591205

RESUMO

BACKGROUND: The coronavirus E ion channel has previously been studied as a potential target for antiviral therapy, with several compounds found to bind to the channel. However, these compounds have low activity, searching for effective E ion channel inhibitors of great importance. OBJECTIVE: This study aimed to develop a computational approach for designing ligands for the coronaviral E ion channel and identify potential inhibitors based on this approach. METHODS: The structure of the E-ion channel was refined using molecular dynamics, and the pore responsible for binding cage compounds was selected as the inhibitor-binding site. Potential inhibitor structures were identified using molecular docking, and their binding was confirmed using molecular dynamics simulations. RESULTS: A number of potential SARS E ion channel inhibitors have been identified, and the binding modes and possible mechanisms of action of these inhibitors have been clarified. CONCLUSION: This study presents a computational approach that can be used to design ligands for E ion channels and identify potential inhibitors, providing valuable insights into the development of new antiviral therapies. The behavior of the E protein pentamer of SARS-CoV-2 in its native environment was investigated using Molecular Dynamics (MD), resulting in an equilibrated structure that could be used to develop new inhibitors through molecular docking. Simulation of the MD of E-channel complexes with amantadine analogues allowed for the identification of the main types of ligand-protein interactions that are responsible for the good binding of ligands within the channel's inner chamber.

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