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1.
Pak J Med Sci ; 40(8): 1791-1796, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39281243

RESUMEN

Objective: To compare the clinical effects of applying a 3D-printed ACT titanium trabecular intervertebral fusion cage and a Polyetheretherketone (PEEK) cage in posterior lumbar interbody fusion (PLIF). Methods: This was a clinical comparative study. Forty patients with degenerative lumbar diseases admitted at The Second People's Hospital of Dalian from January 2020 to December 2021 were selected and divided into an observation group (3D cage) and a control group (PEEK cage) using the random number table method, with each group of 20 cases. The visual analogue scale (VAS) scores, Japanese Orthopaedic Association (JOA) scores, Cobb angles at fusion segments, intervertebral height and intervertebral fusion situations of the patients between the groups were compared. Results: No significant differences were found in their operation time, intraoperative blood losses and operation related complications(p>0.05). In terms of postoperative VAS and JOA scores in both groups, they are all significantly improved compared with those before the operation, and their differences are also statistically significant(p<0.05). However, no statistical significance exists in inter-group differences(p>0.05). Postoperative Cobb angles and intervertebral height of patients in both groups are considerably bettered compared with those before the operation. Their differences show statistical significance(p<0.05), while inter-group differences are proved to be not statistically significant(p>0.05). Conclusions: Applying a 3D-printed ACT titanium trabecular intervertebral fusion cage or PEEK cage in PLIF has the potential to improve clinical symptoms of patients with degenerative lumbar diseases, and restore the Cobb angle and intervertebral height. 3D-printed ACT titanium trabecular intervertebral fusion cage can accelerate intervertebral fusion without increasing operation related complications.

2.
Front Behav Neurosci ; 18: 1457894, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296476

RESUMEN

Locomotor activity can serve as a readout to identify discomfort and pain. Therefore, monitoring locomotor activity following interventions that induce potential discomfort may serve as a reliable method for evaluating animal health, complementing conventional methods such as body weight measurement. In this study, we used the digital ventilated cage (DVC®) system for the assessment of circadian locomotor activity, in addition to body weight monitoring, following intracranial stereotaxic surgery in an Alzheimer's disease mouse model (C57BL/6J/APPswe/PSEN1dE9). Stereotaxic surgery did not affect the organization of circadian locomotor activity of both 7-8-week-old and 19-21-week-old mice. However, we observed that both young and old mice exhibited a significant decrease in activity during the dark phase. Also, our study shows that changes in locomotor activity exhibit higher sensitivity in detecting alterations indicative of animal health compared to measuring body weight. In contrast to 7-8-week-old mice, where we observed no genotypic differences in locomotor activity, 19-21-week-old APP/PS1 mice showed increased locomotor activity compared to wild-type mice. Furthermore, our analyses revealed that a subset of the 7-8-week-old mice showed increased locomotor activity during the initial peak of the dark phase. One mouse experienced sudden death early in life, possibly due to epileptic seizures. Altogether, our findings affirm continuous activity measurements as used in the DVC® as a highly valuable objective method for post-surgical welfare monitoring. Its discerning capacity not only facilitates circadian locomotor rhythm assessment but also enables the identification of individual aberrant activity patterns, possibly indicative of epileptic seizures.

3.
Heliyon ; 10(16): e36448, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39253123

RESUMEN

To investigate the ability of sulfonated polyetheretherketone (SPEEK) to promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and compare the effects of different degrees of sulfonation (DS), SPEEK was made with two different DS. The L-SPEEK group had a lower DS, while the H-SPEEK group had a higher DS. The physicochemical properties of both species were evaluated by scanning electron microscopy (SEM), capitilize Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Then, proliferation and osteogenic differentiation between the two groups and with pure polyetheretherketone (PEEK) were compared after surface inoculation of bone marrow mesenchymal stem cells (BMSCs). Scanning electron microscopy (SEM) revealed that the surface of the PEEK substrates could be smooth or coarse, and the degree of roughness increased with increasing sulfonation. FTIR spectroscopy showed that both the L-SPEEK and H-SPEEK samples contained sulfonic acid. TGA and XRD revealed that the components in the two groups were the same, but the intensities were different. After BMSC inoculation, a CCK8 assay revealed that the cells proliferated more on the H-SPEEK surface and little on the L-SPEEK surface compared with the PEEK surface. Then, osteogenic differentiation was verified by immunofluorescence staining for OCN and Runx2, which indicated that H-SPEEK had the greatest effect on improving differentiation. The results of alizarin red staining (ARS) and alkaline phosphatase staining (APS) also revealed this trend. Sulfonation can change the microsurface of PEEK, which can improve both BMSC proliferation and osteogenic differentiation.

4.
Open Res Eur ; 4: 108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39257918

RESUMEN

Background: Due to the lack of complexity and variety of stimuli, conventional housing conditions of laboratory mice do not allow these animals to fully express their behavioral repertoire, including manipulative and cognitive activities. Therefore, we designed mechanical puzzles, so-called lockboxes, for mice that can be provided in their home cages. We investigated the impact of the lockbox enrichment on their phenotype and affective state when compared to conventional housing (CH) and super-environmental enrichment (SEE). Methods: Young adult female C57BL/6JCrl mice were examined before and after 2-month exposure to the different types of enrichment in a phenotyping test battery, including tests for trait and state anxiety-related behavior, calorimetric measurements, body weight measurements, the analysis of stress hormone metabolite concentrations, and sequential problem-solving abilities with a novel lockbox. At the end of the study, adrenal gland weights were determined and pathohistological evaluation was performed. For all continuous variables, the relative variability was calculated. Results: While the different types of enrichment affected trait anxiety-related behavior, neither state anxiety-related behavior nor physiological variables (i.e., bodyweight, resting metabolic rate, stress hormone metabolite concentrations, adrenal gland weights) were influenced. LE improved sequential problem-solving (i.e., solving novel lockboxes) when compared to SEE. Regardless of the housing condition, the relative variability increased in most variables over time, although the coefficient of variation decreased for some variables, especially in animals with access to LE. There was no evidence of toxicopathological effects associated with the material from which the lockboxes were made. Conclusions: All lockboxes are available as open-source tool. LE revealed beneficial effects on the affective state of laboratory mice and their performance in solving novel lockboxes. Neither relevant phenotype of the mice nor reproducibility of the data were compromised by LE, similar to SEE. The lockboxes may also be used as novel approach for assessing cognition in mice.

5.
ISA Trans ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39294085

RESUMEN

To address the vibration problem induced by rotor eccentricity in a composite cage rotor bearingless induction motor(CCR-BIM), a vibration compensation control approach based on the fuzzy coefficient adaptive-linear-neuron is proposed. Firstly, the CCR-BIM mathematical model and the mechanism of unbalanced vibration are investigated, obtaining the expression of rotor displacement when the rotor is unbalanced. Afterwards, the displacement is decomposed by the fuzzy coefficient adaptive-linear-neuron algorithm to obtain the harmonic component related to vibration, and the value range of the weight coefficient is determined using stability analysis. Furthermore, through analyzing the shortcomings of the traditional PID vibration compensation method, a rotor vibration compensation method based on the fuzzy coefficient adaptive-linear-neuron is put forward to achieve high-performance vibration compensation control. Finally, the PID method and the proposed fuzzy coefficient adaptive-linear-neuron algorithm are simulated and verified by experiments. The findings demonstrate that the proposed algorithm successfully not only suppresses rotor unbalanced vibration but also exhibiting great dynamic performance.

6.
Water Res ; 266: 122353, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39241380

RESUMEN

Antimicrobial resistance (AMR) is a global challenge that has impacted aquaculture and surrounding marine environments. In this study, a year-long monitoring program was implemented to evaluate AMR in two different aquaculture settings (i.e., open cage farming, recirculating aquaculture system (RAS)) and surrounding marine environment within a tropical coastal region. The objectives of this study are to (i) investigate the prevalence and co-occurrence of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARGs), antibiotics (AB) and various associated chemical compounds at these study sites; (ii) explore the contributing factors to development and propagation of AMR in the coastal environment; and (iii) assess the AMR risks from different perspectives based on the three AMR determinants (i.e., ARB, ARGs and AB). Key findings revealed a distinct pattern of AMR across the different aquaculture settings, notably a higher prevalence of antibiotic-resistant Vibrio at RAS outfalls, suggesting a potential accumulation of microorganisms within the treatment system. Despite the relative uniform distribution of ARGs across marine sites, specific genes such as qepA, blaCTX-M and bacA, were found to be abundant in fish samples, especially from the RAS. Variations in chemical contaminant prevalence across sites highlighted possible anthropogenic impacts. Moreover, environmental and seasonal variations were found to significantly influence the distribution of ARGs and chemical compounds in the coastal waters. Hierarchical cluster analysis that was based on ARGs, chemical compounds and environmental data, categorized the sites into three distinct clusters which reflected strong association with location, seasonality and aquaculture activities. The observed weak correlations between ARGs and chemical compounds imply that low environmental concentrations may be insufficient for resistance selection. A comprehensive risk assessment using methodologies such as the multiple antibiotic resistance (MAR) index, comparative AMR risk index (CAMRI) and Risk quotient (RQ) underscored the complexity of AMR risks. This research significantly contributes to the understanding of AMR dynamics in natural aquatic systems and provides valuable insights for managing and mitigating AMR risks in coastal environments.

7.
J Orthop Surg Res ; 19(1): 569, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285287

RESUMEN

BACKGROUND: Congenital craniovertebral deformity, including basilar invagination (BI) and atlantoaxial instability (AAI), are often associated with three-dimensional (3D) deformity, such as C1-2 rotational deformity, craniocervical kyphosis, C1 lateral inclination, among other abnormalities. Effective management of these conditions requires the restoration of the 3D alignment to achieve optimal reduction. Recently, 3D printing technology has emerged as a valuable tool in spine surgery, offering the significant advantage of allowing surgeons to customize the prosthesis design. This innovation provides an ideal solution for precise 3D reduction in the treatment of craniovertebral deformities. OBJECTIVE: This study aims to describe our approach to individualized computer-simulated reduction and the design of C1-2 intra-articular 3D printed porous titanium alloy cages for the quantitative correction of craniovertebral junction deformities. METHODS: A retrospective analysis was conducted on patients with craniovertebral deformities treated at our institution using individualized 3D-printed porous titanium alloy cages. Preoperative CT data were used to construct models for 3D realignment simulations. Cage designs were tailored to the simulated joint morphology following computer-assisted realignment. Preoperative and postoperative parameters were statistically analyzed. RESULTS: Fourteen patients were included in the study, with a total of 28 3D-printed porous titanium alloy cages implanted. There were no cases of C2 nerve root resection or vertebral artery injury. All patients experienced symptom relief and stable implant fixation achieved in all cases. No implant-related complications were reported. CONCLUSION: The use of individualized computer-simulated reduction and the design of C1-2 intra-articular 3D printed porous titanium alloy cage facilitates precise 3D realignment in patients with craniovertebral deformities, demonstrating effectiveness in symptom relief and stability.


Asunto(s)
Aleaciones , Impresión Tridimensional , Titanio , Humanos , Masculino , Femenino , Estudios Retrospectivos , Adulto , Adolescente , Adulto Joven , Articulación Atlantoaxoidea/cirugía , Articulación Atlantoaxoidea/diagnóstico por imagen , Articulación Atlantoaxoidea/anomalías , Porosidad , Persona de Mediana Edad , Niño , Diseño de Prótesis , Vértebras Cervicales/cirugía , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/anomalías
8.
Angew Chem Int Ed Engl ; : e202416289, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39288107

RESUMEN

The construction of solar-to-chemical conversion system by mimicking the photosynthetic network of the chloroplast holds great promise on efficient solar energy utilization. We developed an artificial photosynthetic cell (APC) based on molecular biomimetic thylakoid (CoTPP-FePy) to split water into hydrogen and oxygen (H2 and O2) at low driving voltage (1.1 V) and neutral condition (pH≈7). The CoTPP-FePy can emulate the light reaction in thylakoids to produce O2 by coupling light harvesting, photocatalysis, and electron/energy storage (FeIII/FeII-Py). Subsequently, a membrane electrode assembly (MEA) were employed to simulate the dark reaction, wherein the proton, electron and energy generated by the light reaction can drive the H2 producing process. By a temporally and spatially coupling of the light and dark reactions, the resulting APC achieved a solar conversion efficiency of 3.1%, exceeding that of natural photosynthetic systems and demonstrating the potential of artificial photosynthesis.

9.
Poult Sci ; 103(12): 104281, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39284265

RESUMEN

Providing perches in cage-free (CF) housing offers significant benefits for laying hens, such as improved leg muscle development, bone health, reduced abdominal fat, and decreased fear and aggression. A precise detection method is essential to ensure that hens engage in perching behavior from an early age, as manual observation is often labor-intensive and sometimes inaccurate. The objectives of this study were to (1) develop and test a deep learning model for detecting perching behavior; and (2) evaluate the optimal model's performance on detecting perching behavior of laying hens of different ages. In this study, recent deep learning models, that is, YOLOv8s-PB, YOLOv8x-PB, YOLOv7-PB, and YOLOv7x-PB, were developed, trained and compared in detecting perching behavior in 4 CF rooms (200 hens/room). Perch height was up to 1.8 m from the litter floor and situated 1.5 m below the cameras. A total of 3,000 images were used, with each image featuring at least 1 hen perching. The models' detection accuracies and their performance across different age groups of hens were compared using 1-way ANOVA at a 5% significance level. The results showed that the YOLOv8x-PB model outperform all other models used, achieving the precision of 94.80%, recall of 95.10%, and mean average precision (mAP@0.50) of 97.60%. While all models proved over 94% detection precision. With optimal model, PB detection precision was highest (97.40%) for peaking phase followed by prelay (95.20%), grower (94.80%), developer (94.70%) and layers (92.70%) phases while the lowest detection precision (88.80%) was for starter phase. Detection performance was somewhat reduced by the overlapping of birds during perching and occlusion. Overall, the YOLOv8x-PB model was the most optimal in detecting perching behavior, proposing a valuable tool for CF producers to monitor the perching activities of laying hens automatically.

10.
Poult Sci ; 103(11): 104248, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39217664

RESUMEN

To explore the differences in foie gras performance between geese raised in cages and on the ground, we conducted an integrative analysis of liver transcriptome and gut microbial metagenomes. The results showed extremely significant differences in the liver weight (P < 0.01) and liver lipid accumulation of FRS and CRS groups. The levels of triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) of CRS were significantly higher than those of FRS (P < 0.05). Transcriptome analysis showed that 3,917 upregulated and 1,395 downregulated genes were identified, and lipid metabolism pathway and fatty acid metabolism were significantly enriched. Analysis of cecum microbiota revealed that several inflammation-related bacteria (including Gallibacterium, Escherichia-Shigella, Desulfovibrio, Alistipes, and Fournierella) were enriched in CRS, while beneficial bacteria (including Lactobacillus, Limosilactobacillus, and Ligilactobacillus) were significantly enriched in FRS. In conclusion, CRS was better than FRS in foie gras production, which was more conducive to lipid deposition in the goose liver.

11.
Cureus ; 16(8): e66256, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39238727

RESUMEN

The need for an artificial scaffold in very large bone defects is clear, not only to limit the risk of graft harvesting but also to improve clinical success. The use of custom osteoconductive scaffolds made from biodegradable polyester and ceramics can be a valuable patient-friendly option, especially in case of a concomitant infection. Multiple types of scaffolds for the Masquelet procedure (MP) are available. However, these frequently demonstrate central graft involution when defects exceed a certain size and the complication rates remain high. This paper describes three infected tibial defect nonunions with a segmental defect over 10 centimeters long treated with a three-dimensional (3D)-printed polycaprolactone-tricalcium phosphate (PCL-TCP) cage in combination with biological adjuncts. Three male patients, between the ages of 37 and 47, were treated for an infected tibial defect nonunion after sustaining Gustilo grade 3 open fractures. All had a segmental midshaft bone defect of more than 10 centimeters (range 11-15cm). First-stage MPs consisted of extensive debridement, external fixation, and placement of anterior lateral thigh flaps. Positive cultures were obtained from all patients during this first stage, which were treated with specific systemic antibiotics for 12 weeks. The second-stage MP was carried out at least two months after the first stage. CT scans were obtained after the first stage to manufacture defect-specific cages. In the final procedure, a custom 3D-printed PCL-TCP cage (Osteopore, Singapore) was placed in the defect in combination with biological adjuncts (BMAC, RIA-derived autograft, iFactor, and BioActive Glass). Bridging of the defect, assessed at six months by CT, was achieved in all cases. SPECT scans six months post-operatively demonstrated active bone regeneration, also involving the central part of the scaffold. All three patients regained function and reported less pain with full weight bearing. This case report shows that 3D-printed PCL-TCP cages in combination with biological adjuncts are a novel addition to the surgical treatment of very large bone defects in (infected) post-traumatic nonunion of the tibia. This combination could overcome some of the current drawbacks in this challenging indication.

12.
Theranostics ; 14(12): 4861-4873, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239515

RESUMEN

Rationale: Theranostic nanoplatforms exert a vital role in facilitating concurrent real-time diagnosis and on-demand treatment of diseases, thereby making contributions to the improvement of therapeutic efficacy. Nevertheless, the structural intricacy and the absence of well-defined integration of dual functionality persist as challenges in the development of theranostic nanoplatforms. Methods: We develop an atomically precise theranostic nanoplatform based on metal-organic cage (MOC) to provide magnetic resonance imaging (MRI) guided chemodynamic therapy (CDT) for cancer therapy and assess the theranostic performance both in vitro and in vivo. Through UV-vis spectroscopy, electron paramagnetic resonance (EPR), confocal microscopy, flow cytometry, immunofluorescence staining, and western blotting, the ability of MOC-Mn to generate •OH and the subsequent inhibition of HeLa cells was confirmed. Results: The MOC-Mn composed of manganese and calixarene was successfully synthesized and comprehensively characterized. The catalytic activity of manganese within MOC-Mn facilitated the efficient generation of hydroxyl radicals (•OH) through a Fenton-like reaction, leveraging the high concentrations of hydrogen peroxide in the tumor microenvironment (TME). Additionally, its capacity to prolong the T1 relaxation time and augment the MR signal was observed. The theranostic efficacy was verified via rigorous in vitro and in vivo experiments, indicating that MOC-Mn offered clearer visualization of tumor particulars and substantial suppression of tumor growth. Conclusion: This study showcases a precise MRI-guided CDT theranostic nanoplatform for cancer therapy, thereby promoting the advancement of precise nanomedicine and structure-function research.


Asunto(s)
Imagen por Resonancia Magnética , Nanomedicina Teranóstica , Nanomedicina Teranóstica/métodos , Humanos , Animales , Células HeLa , Imagen por Resonancia Magnética/métodos , Ratones , Manganeso/química , Ratones Desnudos , Femenino , Radical Hidroxilo/metabolismo , Radical Hidroxilo/química , Neoplasias/tratamiento farmacológico , Neoplasias/diagnóstico por imagen , Ratones Endogámicos BALB C , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Nanopartículas/química
13.
Angew Chem Int Ed Engl ; : e202416884, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39275956

RESUMEN

Post-modification of porous materials with molecular modulators has emerged as a well-established strategy for improving gas adsorption and separation. However, a notable challenge lies in maintaining porosity and the limited applicability of the current method. In this study, we employed the mechanochemical "Cage-on-MOF" strategy, utilizing porous coordination cages (PCCs) with intrinsic pores and apertures as surface modulators to improve the gas adsorption and separation properties of the parent MOFs. We demonstrated the fast and facile preparation of 28 distinct MOF@PCC composites by combining 7 MOFs with 4 PCCs with varying aperture sizes and exposed functional groups through a mechanochemical reaction in 5 mins. Only the combinations of PCCs and MOFs with closely matched aperture sizes exhibited enhanced gas adsorption and separation performance. Specifically, MOF-808@PCC-4 exhibited a significantly increased C2H2 uptake (+64%) and a longer CO2/C2H2 separation retention time (+40%). MIL-101@PCC-4 achieved a substantial C2H2 adsorption capacity of 6.11 mmol/g. This work not only highlights the broad applicability of the mechanochemical "Cage-on-MOF" strategy for the functionalization of a wide range of MOFs but also establishes potential design principles for the development of hybrid porous materials with enhanced gas adsorption and separation capabilities, along with promising applications in catalysis and intracellular delivery.

14.
Animals (Basel) ; 14(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39272300

RESUMEN

The speed and accuracy of navigation road extraction and driving stability affect the inspection accuracy of cage chicken coop inspection robots. In this paper, a new grayscale factor (4B-3R-2G) was proposed to achieve fast and accurate road extraction, and a navigation line fitting algorithm based on the road boundary features was proposed to improve the stability of the algorithm. The proposed grayscale factor achieved 92.918% segmentation accuracy, and the speed was six times faster than the deep learning model. The experimental results showed that at the speed of 0.348 m/s, the maximum deviation of the visual navigation was 4 cm, the average deviation was 1.561 cm, the maximum acceleration was 1.122 m/s2, and the average acceleration was 0.292 m/s2, with the detection number and accuracy increased by 21.125% and 1.228%, respectively. Compared with inertial navigation, visual navigation can significantly improve the navigation accuracy and stability of the inspection robot and lead to better inspection effects. The visual navigation system proposed in this paper has better driving stability, higher inspection efficiency, better inspection effect, and lower operating costs, which is of great significance to promote the automation process of large-scale cage chicken breeding and realize rapid and accurate monitoring.

15.
J Surg Case Rep ; 2024(9): rjae582, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39267909

RESUMEN

This report describes two similar cases in which the distal forearm was compressed between the rib cage and floor for a prolonged period owing to immobility, resulting in severe compartment syndrome and extensive penetrating necrosis in the forearm. The cases were a 59-year-old man with cervical spondylolisthesis and a 65-year-old man suspected of having Parkinson's disease. A distinctive necrotic pattern characterized by necrosis in the volar and dorsal compartments, preservation of the lateral compartment, and retention of the radial artery was commonly observed in both cases. Despite the anticipated nonfunctional outcome of the salvaged limb, a two-lobed free latissimus dorsi musculocutaneous flap transfer with interposition of the thoracodorsal nerve in the median nerve defect was performed in both cases. Although the salvaged limbs were nonfunctional, the patients were able to use it for activities such as getting up and other daily tasks.

16.
Chemistry ; : e202400368, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225776

RESUMEN

The reaction of the bicyclic silicon(I) ring compound Si4{N(SiMe3)Mes}4 1 with strong zwitterionic character and moderate sterical demand of the amido substituents with two equivalents of KC8 was investigated. This resulted in the unexpected abstraction of two amido substituents from 1 and additionally in dimerization to a dianionic Si8 cluster compound 2 with four unsubstituted silicon atoms and two [K([18]crown-6)]+ counter cations. Performing this reaction in the absence of [18]crown-6 results in release of only one amido substituent from 1 and dimerization to a dianionic Si8 cluster compound 3 with only two unsubstituted silicon atoms. This reaction with KC8 was repeated and trapping agents such as SiMe3Cl and tBuCl were added in-situ whereupon the second isolated homocyclic silylene 4 and a monoanionic hydride and tBu substituted Si8 cluster 5 with one unsubstituted silicon atom were isolated. Furthermore, 1 was reacted with KOtBu which resulted in the selective abstraction of one SiMe3 group and formation of the tetrahedral silanide 6 with one imido substituent bridging an edge of the tetrahedron.

17.
Biomater Adv ; 165: 214001, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39216317

RESUMEN

Artificial periosteum is deemed a novel strategy for inducing endogenous bone regeneration, but ideal periosteum substitutes achieved by orchestrating a biomimetic microenvironment for bone regeneration remain a significant challenge. Here, we design and fabricate a hybridized nanofiber-based artificial periosteum with boosted osteoinduction properties. Via a "molecular cage" biomineralization strategy, nano-hydroxyapatite (nano-HAp) with a controllable size (∼22 nm) and excellent dispersion serves as unique nano-additives for water-soluble polyvinyl-alcohol (PVA)-based artificial periosteum. The PVA/HAp composite is electrospun into nanofibers to replicate the extracellular-matrix-inspired nanostructure for inducing cell adhesion, proliferation, and fate manipulation. A simple post-crosslinking treatment is subsequently applied to further booster its mechanical strength (6.6 MPa) and swelling stability. The optimized sample of C-PVA/HAp (10 wt% nano-HAp) artificial periosteum features excellent biocompatibility and remarkable in vitro mineralization. Cell experiments demonstrate that its effectively boasted cell modulation for enhanced osteogenesis without the aid of growth factors, showing a possible activation of the ERK/MAPK signaling pathway. This work provides an effective strategy for designing novel HAp nano-additives and expands the possibility of biomimetic fabrication for more advanced nanofiber-based artificial periosteum.


Asunto(s)
Durapatita , Nanofibras , Osteogénesis , Periostio , Alcohol Polivinílico , Nanofibras/química , Alcohol Polivinílico/química , Durapatita/química , Durapatita/farmacología , Osteogénesis/efectos de los fármacos , Humanos , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Regeneración Ósea/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Adhesión Celular/efectos de los fármacos , Sustitutos de Huesos/química
18.
J Mech Behav Biomed Mater ; 159: 106695, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39186906

RESUMEN

Cage subsidence after instrumented lumbar spinal fusion surgery remains a significant cause of treatment failure, specifically for posterior or transforaminal lumbar interbody fusion. Recent advancements in computational techniques and additive manufacturing, have enabled the development of patient-specific implants and implant optimization to specific functional targets. This study aimed to introduce a novel full-scale topology optimization formulation that takes the structural response of the adjacent bone structures into account in the optimization process. The formulation includes maximum and minimum principal strain constraints that lower strain concentrations in the adjacent vertebrae. This optimization approach resulted in anatomically and mechanically conforming spinal fusion cages. Subsidence risk was quantified in a commercial finite element solver for off-the-shelf, anatomically conforming and the optimized cages, in two representative patients. We demonstrated that the anatomically and mechanically conforming cages reduced subsidence risk by 91% compared to an off-the-shelf implant with the same footprint for a patient with normal bone quality and 54% for a patient with osteopenia. Prototypes of the optimized cage were additively manufactured and mechanically tested to evaluate the manufacturability and integrity of the design and to validate the finite element model.


Asunto(s)
Análisis de Elementos Finitos , Fenómenos Mecánicos , Fusión Vertebral , Fusión Vertebral/instrumentación , Humanos , Vértebras Lumbares/cirugía , Ensayo de Materiales , Fenómenos Biomecánicos , Medicina de Precisión , Estrés Mecánico
19.
Restor Neurol Neurosci ; 42(2): 151-165, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39213108

RESUMEN

Background: Spinal cord injury (SCI) results in lesions that destroy tissue and spinal tracts, leading to deficits in locomotor and autonomic function. We have previously shown that after SCI, surviving motoneurons innervating hindlimb muscles exhibit extensive dendritic atrophy, which can be attenuated by treadmill training or treatment with gonadal hormones post-injury. We have also shown that following SCI, both exercise and treatment with gonadal hormones improve urinary function. Animals exercised with forced running wheel training show improved urinary function as measured by bladder cystometry and sphincter electromyography, and treatment with gonadal hormones improves voiding patterns as measured by metabolic cage testing. Objective: The objective of the current study was to examine the potential protective effects of exercise or hormone treatment on the structure and function of motoneurons innervating the external urethral sphincter (EUS) after contusive SCI. Methods: Gonadally intact young adult male rats received either a sham or a thoracic contusion injury. Immediately after injury, one cohort of animals was implanted with subcutaneous Silastic capsules filled with estradiol (E) and dihydrotestosterone (D) or left blank; continuous hormone treatment occurred for 4 weeks post-injury. A separate cohort of SCI-animals received either 12 weeks of forced wheel running exercise or no exercise treatment starting two weeks after injury. At the end of treatment, urinary void volume was measured using metabolic cages and EUS motoneurons were labeled with cholera toxin-conjugated horseradish peroxidase, allowing for assessment of dendritic morphology in three dimensions. Results: Locomotor performance was improved in exercised animals after SCI. Void volumes increased after SCI in all animals; void volume was unaffected by treatment with exercise, but was dramatically improved by treatment with E + D. Similar to what we have previously reported for hindlimb motoneurons after SCI, dendritic length of EUS motoneurons was significantly decreased after SCI compared to sham animals. Exercise did not reverse injury-induced atrophy, however E + D treatment significantly protected dendritic length. Conclusions: These results suggest that some aspects of urinary dysfunction after SCI can be improved through treatment with gonadal hormones, potentially through their effects on EUS motoneurons. Moreover, a more comprehensive treatment regime that addresses multiple SCI-induced sequelae, i.e., locomotor and voiding deficits, would include both hormones and exercise.


Asunto(s)
Neuronas Motoras , Condicionamiento Físico Animal , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal , Uretra , Micción , Animales , Traumatismos de la Médula Espinal/terapia , Traumatismos de la Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/patología , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/fisiología , Neuronas Motoras/patología , Masculino , Uretra/efectos de los fármacos , Uretra/patología , Micción/efectos de los fármacos , Micción/fisiología , Ratas , Condicionamiento Físico Animal/fisiología , Estradiol/farmacología , Modelos Animales de Enfermedad , Terapia por Ejercicio/métodos
20.
BMC Musculoskelet Disord ; 25(1): 657, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169282

RESUMEN

BACKGROUND: To explore the surgical outcome of enlarged posterior column osteotomy (EPCO) plus intervertebral cage strutting (ICS) for patients with lumbosacral nerve bowstring disease (BSD). METHODS: The clinical data of 27 patients with BSD that surgically treated with EPCO plus ICS from January 2018 to March 2021 were retrospectively reviewed. Patient demographics including age, gender, body mass index (BMI), duration, length of hospital stay, SF-36 were recorded. Surgical data including operation time, blood loss, surgical level, and complications were recorded. Inter-pedicle distance and regional lumbar lordosis was measured at lateral X-ray at both pre- and postoperative. RESULTS: All patients underwent the operation successfully. EPCO plus ICS was performed at L4-L5 in 9 patients, at L5-S1 in 7 patients, at L4-S1 in 6 patients, at L3-L5 in 5 patients. The mean operation time was 96.3 ± 18.0 min, mean blood loss was 350.0 ± 97.9 mL. Relaxation of thecal sac was noticed after pedicle screw-rod compression bilaterally. The mean decrease of inter-pedicle distance was 0.57 ± 0.18 cm, the mean increase of regional lumbar lordosis was 17.6 ± 6.7 degrees. Relaxation of cauda equina within the thecal sac was noticed at intra-operative after pedicle screw-rod compression bilaterally in all the patients. Most patients achieved neurological function improvement at two-year follow up. CONCLUSIONS: EPCO plus ICS procedure is an effective surgical method for lumbosacral nerve BSD through restoring the coordination between column and cord, visual relaxation of cauda equina within the thecal sac at intraoperative is the key factor in determining the relief of neurological function at postoperative.


Asunto(s)
Vértebras Lumbares , Osteotomía , Humanos , Femenino , Masculino , Persona de Mediana Edad , Osteotomía/métodos , Estudios Retrospectivos , Adulto , Vértebras Lumbares/cirugía , Vértebras Lumbares/diagnóstico por imagen , Resultado del Tratamiento , Anciano , Tempo Operativo , Lordosis/cirugía , Lordosis/diagnóstico por imagen , Fusión Vertebral/métodos , Fusión Vertebral/instrumentación
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