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1.
Artículo en Inglés | MEDLINE | ID: mdl-39025101

RESUMEN

BACKGROUND: Globally, fall-related injuries are a substantial problem, and 80% of fatal falls occur in low-income and middle-income countries. We aimed to measure time from injury to hip-fracture surgery in people aged 50 years or older living in low-income and middle-income regions, as well as to measure the proportion of patients with surgical stabilisation of their hip fracture within 72 h of admission to hospital and to identify risk factors associated with surgical delay. METHODS: For this secondary analysis, we analysed data collected from Africa, Latin America, China, India, and Asia (excluding China and India) for the International Orthopaedic Multicentre Study in Fracture Care (INORMUS) between March 29, 2014, and June 15, 2022. Patients from INORMUS were included in this analysis if they were aged 50 years or older and had an isolated, primary hip fracture sustained from a ground-level fall. Staff at participating hospitals identified patients with musculoskeletal injury and referred them for assessment of eligibility. We report time from injury to surgery as three distinct time periods: time from injury to hospital admission, time from admission to surgery, and a total time from injury to surgery. Date and time of injury were self-reported by patients at the time of study recruitment. If time to hospital admission after injury exceeded 24 h, patients reported the primary reason for delayed admission. Reasons for surgery, no surgery, and surgical delay were reported by the treating team. For patients undergoing surgery, multivariable regression analyses were used to identify risk factors for surgical delay. FINDINGS: 4486 adults aged 50 years or older with an isolated, primary hip fracture were enrolled in INORMUS from 55 hospitals in 24 countries. Countries were grouped into five regions: Africa (418 [9·3%] of 4486), Latin America (558 [12·4%]), China (1680 [37·4%]), India (1059 [23·6%]) and Asia (excluding China and India; 771 [17·2%]). Of 4486 patients, 3805 (84·8%) received surgery. The rate of surgery was similar in all regions except in Africa, where only 193 (46·3%) of 418 patients had surgery. Overall, 2791 (62·2%) of 4486 patients were admitted to hospital within 24 h of injury. However, 1019 (22·7%) of 4486 patients had delayed hospital admission of 72 h or more from injury. The two most common reasons for delayed admission of more than 24 h were transfer from another hospital (522 [36·2%] of 1441) and delayed care-seeking because patients thought the injury would heal on its own (480 [33·3%]). Once admitted to hospital, 1451 (38·1%) of 3805 patients who received surgery did so within 72 h (median 4·0 days [IQR 1·7-6·0]). Regional variation was seen in the proportion of patients receiving surgery within 72 h of hospital admission (92 [17·9%] of 514 in Latin America, 53 [27·5%] of 193 in Africa, 454 [30·9%] of 1471 in China, 318 [44·4%] of 716 in Asia [excluding China and India], and 534 [58·6%] of 911 in India). Of all 3805 patients who received operative treatment, 2353 (61·8%) waited 72 h or more from hospital admission. From time of injury, the proportion of patients who were surgically stabilised within 72 h was 889 (23·4%) of 3805 (50 [9·7%] of 517 in Latin America, 31 [16·1%] of 193 in Africa, 277 [18·8%] of 1471 in China, 189 [26·4%] of 716 in Asia [excluding China and India], and 342 [37·5%] of 911 in India). INTERPRETATION: Access to surgery within 72 h of hospital admission was poor, with factors that affected time to surgery varying by region. Data are necessary to understand existing pathways of hip-fracture care to inform the local development of quality-improvement initiatives. FUNDING: The National Health and Medical Research Council of Australia, the Canadian Institutes of Health Research, McMaster Surgical Associates, Hamilton Health Sciences, and the US National Institutes of Health.

2.
Int J Nanomedicine ; 19: 6337-6358, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38946884

RESUMEN

Background: It is well-established that osteoclast activity is significantly influenced by fluctuations in intracellular pH. Consequently, a pH-sensitive gated nano-drug delivery system represents a promising therapeutic approach to mitigate osteoclast overactivity. Our prior research indicated that naringin, a natural flavonoid, effectively mitigates osteoclast activity. However, naringin showed low oral availability and short half-life, which hinders its clinical application. We developed a drug delivery system wherein chitosan, as gatekeepers, coats mesoporous silica nanoparticles loaded with naringin (CS@MSNs-Naringin). However, the inhibitory effects of CS@MSNs-Naringin on osteoclasts and the underlying mechanisms remain unclear, warranting further research. Methods: First, we synthesized CS@MSNs-Naringin and conducted a comprehensive characterization. We also measured drug release rates in a pH gradient solution and verified its biosafety. Subsequently, we investigated the impact of CS@MSNs-Naringin on osteoclasts induced by bone marrow-derived macrophages, focusing on differentiation and bone resorption activity while exploring potential mechanisms. Finally, we established a rat model of bilateral critical-sized calvarial bone defects, in which CS@MSNs-Naringin was dispersed in GelMA hydrogel to achieve in situ drug delivery. We observed the ability of CS@MSNs-Naringin to promote bone regeneration and inhibit osteoclast activity in vivo. Results: CS@MSNs-Naringin exhibited high uniformity and dispersity, low cytotoxicity (concentration≤120 µg/mL), and significant pH sensitivity. In vitro, compared to Naringin and MSNs-Naringin, CS@MSNs-Naringin more effectively inhibited the formation and bone resorption activity of osteoclasts. This effect was accompanied by decreased phosphorylation of key factors in the NF-κB and MAPK signaling pathways, increased apoptosis levels, and a subsequent reduction in the production of osteoclast-specific genes and proteins. In vivo, CS@MSNs-Naringin outperformed Naringin and MSNs-Naringin, promoting new bone formation while inhibiting osteoclast activity to a greater extent. Conclusion: Our research suggested that CS@MSNs-Naringin exhibited the strikingly ability to anti-osteoclasts in vitro and in vivo, moreover promoted bone regeneration in the calvarial bone defect.


Asunto(s)
Regeneración Ósea , Flavanonas , Nanopartículas , Osteoclastos , Dióxido de Silicio , Flavanonas/química , Flavanonas/farmacología , Flavanonas/farmacocinética , Flavanonas/administración & dosificación , Animales , Osteoclastos/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Dióxido de Silicio/química , Concentración de Iones de Hidrógeno , Nanopartículas/química , Ratas , Ratones , Ratas Sprague-Dawley , Quitosano/química , Masculino , Liberación de Fármacos , Porosidad , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Resorción Ósea/tratamiento farmacológico , Células RAW 264.7 , Sistemas de Liberación de Medicamentos/métodos , Diferenciación Celular/efectos de los fármacos
3.
Calcif Tissue Int ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953964

RESUMEN

Ankle osteoarthritis is a relatively understudied condition and the molecular mechanisms involved in its development are not well understood. This investigation aimed to explore the role and underlying molecular mechanisms of Yes-associated protein (YAP) in rat ankle osteoarthritis. The results demonstrated that YAP expression levels were abnormally increased in the ankle osteoarthritis cartilage model. In addition, knockdown of YAP expression was shown to hinder the imbalance in ECM metabolism induced by IL-1ß in chondrocytes, as demonstrated by the regulation of matrix metalloproteinase (MMP)-3, MMP-9, and MMP-13, a disintegrin, metalloprotease with thrombospondin motifs, aggrecan, and collagen II expression. Additional studies revealed that downregulation of YAP expression markedly inhibited the overexpression of ß-catenin stimulated by IL-1ß. Furthermore, inhibition of the Wnt/ß-catenin signaling pathway reversed the ECM metabolism imbalance caused by YAP overexpression in chondrocytes. It is important to note that the YAP-specific inhibitor verteporfin (VP) significantly delayed the progression of ankle osteoarthritis. In conclusion, the findings highlighted the crucial role of YAP as a regulator in modulating the progression of ankle osteoarthritis via the Wnt/ß-catenin signaling pathway. These findings suggest that pharmacological inhibition of YAP can be an effective and critical therapeutic target for alleviating ankle osteoarthritis.

4.
Nano Lett ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837959

RESUMEN

Propane dehydrogenation (PDH) serves as a pivotal intentional technique to produce propylene. The stability of PDH catalysts is generally restricted by the readsorption of propylene which can subsequently undergo side reactions for coke formation. Herein, we demonstrate an ultrastable PDH catalyst by encapsulating PtIn clusters within silicalite-1 which serves as an efficient promoter for olefin desorption. The mean lifetime of PtIn@S-1 (S-1, silicalite-1) was calculated as 37317 h with high propylene selectivity of >97% at 580 °C with a weight hourly space velocity (WHSV) of 4.7 h-1. With an ultrahigh WHSV of 1128 h-1, which pushed the catalyst away from the equilibrium conversion to 13.3%, PtIn@S-1 substantially outperformed other reported PDH catalysts in terms of mean lifetime (32058 h), reaction rates (3.42 molpropylene gcat-1 h-1 and 341.90 molpropylene gPt-1 h-1), and total turnover number (14387.30 kgpropylene gcat-1). The developed catalyst is likely to lead the way to scalable PDH applications.

5.
J Colloid Interface Sci ; 673: 657-668, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38901356

RESUMEN

The orientation-guidance coupled with in-situ activation methodology is developed to synthesize the N-doped porous carbon (NPC) with well-developed porosity and high specific surface area, using coal pitch as a carbon precursor. The orientation-guidance and activation are dedicated to generating microporous and mesoporous channels, respectively. The in-situ N incorporation into the carbon skeleton is realized along with the formation of porous carbon (PC), ensuring the uniformity of N doping. As an electrode material of supercapacitor, benefiting from the robust hexagon-like building block decorated with micro-mesoporous channels and N doping, NPC electrode affords a significant improvement in capacitive energy-storage performance, achieving a specific capacitance of up to 333F g-1 at 1 A/g, which far exceeds those of PC and activated carbon. Notably, even under high mass loading of 10 mg cm-2, the NPC maintains a satisfactory capacitance of 258F g-1 at 1 A/g. When employed as the anode in Li-ion capacitor (LIC), apart from exhibiting enhanced anode behavior compared to graphite anode, NPC also delivers exceptional cyclability. Furthermore, density functional theory calculations have validated the enhanced electrical conductivity and Li storage ability contributed by N doping, providing a theoretical foundation for the observed improvements in electrochemical performance. A full LIC configured with NPC anode delivers extraordinary Ragone performance and outstanding cyclability. This work also proposes a feasible way to realize the oriented conversion of coal pitch into high-performance electrode materials for electrochemical energy-storage devices.

7.
Medicine (Baltimore) ; 103(18): e37979, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701293

RESUMEN

Older children over 8 years old are at higher risk of elbow joint stiffness after treatment of supracondylar humeral fractures. The objective of this study was to improve the Slongo's external fixation system for treating supracondylar humeral fractures in older children. This would be achieved by increasing fixation strength and providing a theoretical basis through finite element analysis and mechanical testing. A 13-year-old female patient with a history of previous fracture was selected for CT data processing to create a three-dimensional model of the distal humerus fracture. Two internal fixation models were established, using the Slongo's external fixation method with Kirschner wire (Group A) and modifying the Slongo's external fixation (Kirschner wire tail fixation) (Group B). The fracture models were then subjected to mechanical loading analysis using Finite Element Analysis Abaqus 6.14 software to simulate separation, internal rotation, and torsion loads. A PVC humeral bone model was used to create a supracondylar fracture model, and the A and B internal fixation methods were applied separately. The anterior-posterior and torsional stresses were measured using the Bose Electroforce3510 testing system, followed by a comparative analysis. The finite element simulation results showed that under the same tensile, torsion, and inversion forces, the osteotomy model fixed with Kirschner wire at the distal end in Group B exhibited smaller tensile stress and deformation compared to the unfixed osteotomy model in Group A. This indicated that the fixation strength of Group B was superior to that of Group A. According to the test results of the Bose Electroforce3510 testing system, a simple linear regression analysis was conducted using SPSS software. The K values of rotation angle-torque tests and front and rear displacement-stress tests were calculated for Groups A and B, with Group B showing higher values than Group A. The results of this study supported the significantly enhanced biomechanical reliability and stability of fracture fixation in Group B, which utilized the modified Slongo's external fixation (Kirschner wire tail fixation). This optimized method provides a new choice for the clinical treatment of supracondylar humeral fractures in older children, backed by both clinical evidence and theoretical basis.


Asunto(s)
Fijadores Externos , Análisis de Elementos Finitos , Fijación de Fractura , Fracturas del Húmero , Humanos , Fracturas del Húmero/cirugía , Femenino , Adolescente , Fijación de Fractura/métodos , Hilos Ortopédicos , Fenómenos Biomecánicos , Tomografía Computarizada por Rayos X
8.
Medicine (Baltimore) ; 103(19): e38065, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38728521

RESUMEN

Knee varus (KV) deformity leads to abnormal forces in the different compartments of the joint cavity and abnormal mechanical loading thus leading to knee osteoarthritis (KOA). This study used computer-aided design to create 3-dimensional simulation models of KOA with varying varus angles to analyze stress distribution within the knee joint cavity using finite element analysis for different varus KOA models and to compare intra-articular loads among these models. Additionally, we developed a cartilage loading model of static KV deformity to correlate with dynamic clinical cases of cartilage injury. Different KV angle models were accurately simulated with computer-aided design, and the KV angles were divided into (0°, 3°, 6°, 9°, 12°, 15°, and 18°) 7 knee models, and then processed with finite element software, and the Von-Mises stress distribution and peak values of the cartilage of the femoral condyles, medial tibial plateau, and lateral plateau were obtained by simulating the human body weight in axial loading while performing the static extension position. Finally, intraoperative endoscopy visualization of cartilage injuries in clinical cases corresponding to KV deformity subgroups was combined to find cartilage loading and injury correlations. With increasing varus angle, there was a significant increase in lower limb mechanical axial inward excursion and peak Von-Mises stress in the medial interstitial compartment. Analysis of patients' clinical data demonstrated a significant correlation between varus deformity angle and cartilage damage in the knee, medial plateau, and patellofemoral intercompartment. Larger varus deformity angles could be associated with higher medial cartilage stress loads and increased cartilage damage in the corresponding peak stress area. When the varus angle exceeds 6°, there is an increased risk of cartilage damage, emphasizing the importance of early surgical correction to prevent further deformity and restore knee function.


Asunto(s)
Cartílago Articular , Análisis de Elementos Finitos , Articulación de la Rodilla , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/fisiopatología , Osteoartritis de la Rodilla/cirugía , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Articulación de la Rodilla/fisiopatología , Masculino , Soporte de Peso/fisiología , Fenómenos Biomecánicos , Persona de Mediana Edad , Estrés Mecánico , Femenino , Simulación por Computador , Anciano
9.
J Orthop Surg Res ; 19(1): 265, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671500

RESUMEN

Hormonal necrosis of the femoral head is caused by long-term use of glucocorticoids and other causes of abnormal bone metabolism, lipid metabolism imbalance and blood microcirculation disorders in the femoral head, resulting in bone trabecular fracture, bone tissue necrosis collapse, and hip dysfunction. It is the most common type of non-traumatic necrosis of the femoral head, and its pathogenesis is complex, while impaired blood circulation is considered to be the key to its occurrence. There are a large number of microvessels in the femoral head, among which H-type vessels play a decisive role in the "angiogenesis and osteogenesis coupling", and thus have an important impact on the occurrence and development of femoral head necrosis. Glucocorticoids can cause blood flow injury of the femoral head mainly through coagulation dysfunction, endothelial dysfunction and impaired angiogenesis. Glucocorticoids may inhibit the formation of H-type vessels by reducing the expression of HIF-1α, PDGF-BB, VGEF and other factors, thus causing damage to the "angiogenesis-osteogenesis coupling" and reducing the ability of necrosis reconstruction and repair of the femoral head. Leads to the occurrence of hormonal femoral head necrosis. Therefore, this paper reviewed the progress in the study of the mechanism of hormone-induced femoral head necrosis based on microvascular blood flow at home and abroad, hoping to provide new ideas for the study of the mechanism of femoral head necrosis and provide references for clinical treatment of femoral head necrosis.


Asunto(s)
Necrosis de la Cabeza Femoral , Glucocorticoides , Microvasos , Humanos , Necrosis de la Cabeza Femoral/inducido químicamente , Necrosis de la Cabeza Femoral/etiología , Microvasos/patología , Glucocorticoides/efectos adversos , Cabeza Femoral/irrigación sanguínea , Cabeza Femoral/patología , Microcirculación , Neovascularización Patológica/etiología
10.
Orthop Surg ; 16(5): 1143-1152, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38561920

RESUMEN

OBJECTIVE: Medial opening-wedge high tibial osteotomy (MOWHTO) is a surgical procedure to treat medial compartment osteoarthritis in the knee with varus deformity. However, factors such as patellar height (PH) and the sagittal plane's posterior tibial slope angle (PTSA) are potentially overlooked. This study investigated the impact of alignment correction angle guided by computer-designed personalized surgical guide plate (PSGP) in MOWHTO on PH and PTSA, offering insights for enhancing surgical techniques. METHODS: This retrospective study included patients who underwent 3D-printed PSGP-assisted MOWHTO at our institution from March to September 2022. The paired t-tests assessed differences in all preoperative and postoperative measurement parameters. Multivariate linear regression analysis examined correlations between PTSA, CDI (Caton-Deschamps Index), and the alignment correction magnitude. Receiver operating characteristic (ROC) curve analysis determined the threshold of the correction angle, calculating sensitivity, specificity, and area under the curve. RESULTS: A total of 107 patients were included in our study. The CDI changed from a preoperative mean of 0.97 ± 0.13 (range 0.70-1.34) to a postoperative mean of 0.82 ± 0.13 (range 0.55-1.20). PTSA changed from a preoperative mean of 8.54 ± 2.67 (range 2.19-17.55) to a postoperative mean of 10.54 ± 3.05 (range 4.48-18.05). The t-test revealed statistically significant changes in both values (p < 0.05). A significant alteration in patellar height occurred when the correction angle exceeded 9.39°. Moreover, this paper illustrates a negative correlation between CDI change and the correction angle and preoperative PTSA. Holding other factors constant, each 1-degree increase in the correction angle led to a 0.017 decrease in postoperative CDI, and each 1-degree increase in preoperative PTSA resulted in a 0.008 decrease in postoperative CDI. PTSA change was positively correlated only with the correction angle; for each 1-degree increase in the opening angle, postoperative PTS increased by 0.188, with other factors constant. CONCLUSION: This study highlights the effectiveness and precision of PSGP-assisted MOWHTO, focusing on the impact of alignment correction on PH and PTSA. These findings support the optimization of PSGP technology, which offers simpler, faster, and safer surgeries with less radiation and bleeding than traditional methods. However, PSGP's one-time use design and the learning curve required for its application are limitations, suggesting areas for further research.


Asunto(s)
Osteoartritis de la Rodilla , Osteotomía , Rótula , Cirugía Asistida por Computador , Tibia , Humanos , Estudios Retrospectivos , Osteotomía/métodos , Femenino , Masculino , Persona de Mediana Edad , Tibia/cirugía , Rótula/cirugía , Adulto , Osteoartritis de la Rodilla/cirugía , Cirugía Asistida por Computador/métodos , Anciano , Impresión Tridimensional
11.
Pathol Res Pract ; 257: 155312, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38663177

RESUMEN

Current treatments for orthopaedic illnesses frequently result in poor prognosis, treatment failure, numerous relapses, and other unpleasant outcomes that have a significant impact on patients' quality of life. Cell-free therapy has emerged as one of the most promising options in recent decades for improving the status quo. As a result, using exosomes produced from various cells to modulate ferroptosis has been proposed as a therapeutic method for the condition. Exosomes are extracellular vesicles that secrete various bioactive chemicals that influence disease treatment and play a role in the genesis and progression of orthopaedic illnesses. Ferroptosis is a recently defined kind of controlled cell death typified by large iron ion buildup and lipid peroxidation. An increasing number of studies indicate that ferroptosis plays a significant role in orthopaedic illnesses. Exosomes, as intercellular information transfer channels, have been found to play a significant role in the regulation of ferroptosis processes. Furthermore, accumulating research suggests that exosomes can influence the course of many diseases by regulating ferroptosis in injured cells. In order to better understand the processes by which exosomes govern ferroptosis in the therapy of orthopaedic illnesses. This review discusses the biogenesis, secretion, and uptake of exosomes, as well as the mechanisms of ferroptosis and exosomes in the therapy of orthopaedic illnesses. It focuses on recent research advances and exosome mechanisms in regulating iron death for the therapy of orthopaedic illnesses. The present state of review conducted both domestically and internationally is elucidated and anticipated as a viable avenue for future therapy in the field of orthopaedics.


Asunto(s)
Exosomas , Ferroptosis , Ferroptosis/fisiología , Humanos , Exosomas/metabolismo , Animales , Hierro/metabolismo
12.
Angew Chem Int Ed Engl ; 63(23): e202404983, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38563622

RESUMEN

Syngas conversion serves as a gas-to-liquid technology to produce liquid fuels and valuable chemicals from coal, natural gas, or biomass. During syngas conversion, sintering is known to deactivate the catalyst owing to the loss of active surface area. However, the growth of nanoparticles might induce the formation of new active sites such as grain boundaries (GBs) which perform differently from the original nanoparticles. Herein, we reported a unique Cu-based catalyst, Cu nanoparticles with in situ generated GBs confined in zeolite Y (denoted as activated Cu/Y), which exhibited a high selectivity for C5+ hydrocarbons (65.3 C%) during syngas conversion. Such high selectivity for long-chain products distinguished activated Cu/Y from typical copper-based catalysts which mainly catalyze methanol synthesis. This unique performance was attributed to the GBs, while the zeolite assisted the stabilization through spatial confinement. Specifically, the GBs enabled H-assisted dissociation of CO and subsequent hydrogenation into CHx*. CHx* species not only serve as the initiator but also directly polymerize on Cu GBs, known as the carbide mechanism. Meanwhile, the synergy of GBs and their vicinal low-index facets led to the CO insertion where non-dissociative adsorbed CO on low-index facets migrated to GBs and inserted into the metal-alkyl bond for the chain growth.

13.
BMC Musculoskelet Disord ; 25(1): 208, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459524

RESUMEN

PURPOSE: To compare the postoperative rehabilitation of femoral neck fractures treated with robot-assisted nailing and freehand nailing. METHODS: We systematically searched the PubMed, EMBASE, Cochrane, China National Knowledge Infrastructure(CNKI), WanFang database, China Science and Technology Journal Database (VIP) and Web of Science databases to identify potentially eligible articles. Indispensable data such as the year of publication, country, study type, robot type, age, number of patients, sex distribution, study design, and outcome indicators were extracted. The outcome indicators of interest included healing rate, length of healing time, Harris score, operation time, frequency of X-ray fluoroscopy, frequency of guide pin insertion, and intraoperative blood loss. RevMan 5.4.1 was used for the meta-analysis. RESULTS: Fourteen studies with 908 participants were included in this meta-analysis. The results showed that in terms of healing rate (SMD = 2.75, 95% CI, 1.03 to 7.32, P = 0.04) and Harris score (SMD = 2.27, 95% CI, 0.79 to 3.75, P = 0.003), robot-assisted screw placement technique scores were higher than the traditional freehand technique. Additionally, operative time (SMD = -12.72, 95% CI, -19.74 to -5.70, P = 0.0004), healing time (SMD = -13.63, 95% CI, -20.18 to -7.08, P < 0.0001), frequency of X-ray fluoroscopy (SMD = - 13.64, 95% CI, - 18.32 to - 8.95, P < 0.00001), frequency of guide pin insertion (SMD = - 7.95, 95% CI, - 10.13 to - 5.76, P < 0.00001), and intraoperative blood loss (SMD = - 17.33, 95% CI, - 23.66 to - 11.00, P < 0.00001) were lower for patients who underwent robotic-assisted screw placement than those for patients who underwent the conventional freehand technique. CONCLUSION: Compared to the freehand nailing technique, robot-assisted nailing helps improve postoperative healing rates in patients with femoral neck fractures; shortens healing times; better restores hip function; reduces the number of intraoperative fluoroscopies, guides pin placements; reduces intraoperative bleeding; and increases perioperative safety.


Asunto(s)
Fracturas del Cuello Femoral , Procedimientos Quirúrgicos Robotizados , Humanos , Pérdida de Sangre Quirúrgica , Tornillos Óseos , Fracturas del Cuello Femoral/rehabilitación , Fracturas del Cuello Femoral/cirugía , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/métodos , Resultado del Tratamiento
14.
Nano Lett ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38511842

RESUMEN

Methane oxidation using molecular oxygen remains a grand challenge in which the obstacle is not only the activation of methane but also the reaction with oxygen, considering the mismatch of the ground spin states. Herein, we report TiO2-supported Pt nanocrystals (Pt/TiO2) with surface Pt-Ti alloyed layers that directly convert methane into oxygenates by using O2 as the oxidant with the assistance of CO. The oxygenate yield reached 749.8 mmol gPt-1 in a H2O aqueous solution over 0.1% Pt/TiO2 under 31 bar of mixed gas (20:5:6 CH4:CO:O2) at 150 °C for 3 h, while the CH3OH selectivity was 62.3%. On the basis of the control experiments and spectroscopic results, we identified the surface Pt-Ti alloy as the active sites. Moreover, CO promoted the dissociation of O2 on the surface of Pt-Ti alloyed layers and the subsequent activation of CH4 to form oxygenated products.

15.
World Neurosurg ; 183: e818-e824, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38218442

RESUMEN

BACKGROUND: The accurate diagnosis of fresh vertebral fractures (VFs) was critical to optimizing treatment outcomes. Existing studies, however, demonstrated insufficient accuracy, sensitivity, and specificity in detecting fresh fractures using magnetic resonance imaging (MRI), and fall short in localizing the fracture sites. METHODS: This prospective study comprised 716 patients with fresh VFs. We obtained 849 Short TI Inversion Recovery (STIR) image slices for training and validation of the AI model. The AI models employed were yolov7 and resnet50, to detect fresh VFs. RESULTS: The AI model demonstrated a diagnostic accuracy of 97.6% for fresh VFs, with a sensitivity of 98% and a specificity of 97%. The performance of the model displayed a high degree of consistency when compared to the evaluations by spine surgeons. In the external testing dataset, the model exhibited a classification accuracy of 92.4%, a sensitivity of 93%, and a specificity of 92%. CONCLUSIONS: Our findings highlighted the potential of AI in diagnosing fresh VFs, offering an accurate and efficient way to aid physicians with diagnosis and treatment decisions.


Asunto(s)
Aprendizaje Profundo , Fracturas de la Columna Vertebral , Humanos , Estudios Prospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Imagen por Resonancia Magnética/métodos , Columna Vertebral/patología , Estudios Retrospectivos
16.
Orthop Surg ; 16(1): 196-206, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37933461

RESUMEN

OBJECTIVE: Modic changes (MCs) are the most prevalent classification system for describing intravertebral MRI signal intensity changes. However, interpreting these intricate MRI images is a complex and time-consuming process. This study investigates the performance of single shot multibox detector (SSD) and ResNet18 network-based automatic detection and classification of MCs. Additionally, it compares the inter-observer agreement and observer-classifier agreement in MCs diagnosis to validate the feasibility of deep learning network-assisted detection of classified MCs. METHOD: A retrospective analysis of 140 patients with MCs who underwent MRI diagnosis and met the inclusion and exclusion criteria in Tianjin Hospital from June 2020 to June 2021 was used as the internal dataset. This group consisted of 55 males and 85 females, aged 25 to 89 years, with a mean age of (59.0 ± 13.7) years. An external test dataset of 28 patients, who met the same criteria and were assessed using different MRI equipment at Tianjin Hospital, was also gathered, including 11 males and 17 females, aged 31 to 84 years, with a mean age of 62.7 ± 10.9 years. After Physician 1 (with 15 years of experience) annotated all MRI images, the internal dataset was imported into the deep learning model for training. The model comprises an SSD network for lesion localization and a ResNet18 network for lesion classification. Performance metrics, including accuracy, recall, precision, F1 score, confusion matrix, and inter-observer agreement parameter Kappa value, were used to evaluate the model's performance on the internal and external datasets. Physician 2 (with 1 year of experience) re-labeled the internal and external test datasets to compare the inter-observer agreement and observer-classifier agreement. RESULTS: In the internal dataset, when models were utilized for the detection and classification of MCs, the accuracy, recall, precision and F1 score reached 86.25%, 87.77%, 84.92% and 85.60%, respectively. The Kappa value of the inter-observer agreement was 0.768 (95% CI: 0.656, 0.847),while observer-classifier agreement was 0.717 (95% CI: 0.589, 0.809).In the external test dataset, the model's the accuracy, recall, precision and F1 scores for diagnosing MCs reached 75%, 77.08%, 77.80% and 74.97%, respectively. The inter-observer agreement was 0.681 (95% CI: 0.512, 0.677), and observer-classifier agreement was 0.519 (95% CI: 0.290, 0.690). CONCLUSION: The model demonstrated strong performance in detecting and classifying MCs, achieving high agreement with physicians in MCs diagnosis. These results suggest that deep learning models have the potential to facilitate the application of intelligent assisted diagnosis techniques in the field of spine research.


Asunto(s)
Aprendizaje Profundo , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Reproducibilidad de los Resultados , Imagen por Resonancia Magnética/métodos , Columna Vertebral
17.
Nano Lett ; 24(3): 852-858, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38051031

RESUMEN

Currently, the hydroformylation of short olefins is operated almost exclusively by using Rh catalysts. Considering the high cost and scarcity of rhodium resources, it is important to develop non-noble metal catalysts toward hydroformylation. Herein, we report an efficient cobalt-based catalyst rich in interfacial sites between metallic and oxidized cobalt species for the hydroformylation of short olefin, propene, under a moderate syngas pressure. The catalyst exhibited a high specific activity of 252 mol molCo-1 h-1 in toluene under 2 bar of propene and 40 bar of CO/H2 mixed gas (CO/H2 = 1:1) at 160 °C. According to mechanistic studies, the interface of metallic and oxidized cobalt species promoted the adsorption of CO and propene. Moreover, the interfacial sites lowered the energy barrier for CO* hydrogenation and C-C coupling compared with metallic cobalt.

18.
Orthop Surg ; 16(1): 207-215, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37975209

RESUMEN

OBJECTIVE: Intertrochanteric fracture is one type of hip fracture, which is the most serious consequence of osteoporosis. Along with the growing elderly population, intertrochanteric fracture is expected to rise increasingly. The aim of this study was to assess excess mortality after intertrochanteric fractures and to identify the predictors of long-term mortality by therapy among patients aged 50 years and older in Tianjin. METHODS: This is a retrospective cohort study on mortality for 3029 patients aged 50 years and older in Tianjin experiencing an intertrochanteric fracture between December 26, 2014 and December 31, 2018. Data were from Tianjin Hospital Hip Fracture (THHF) cohort. Follow-up period was until March 31, 2022. Mortality, excess mortality, and comorbidities were analyzed and stratified by therapy and gender. Time dependent Cox models were performed to estimate the effects of the variables. RESULTS: Absolute mortality for all the patients was 5.90% at 3 months, 12.55% at 12 months, 19.92% at 24 months and 27.28% at 36 months. Absolute mortality for surgical group was 1.57% at 3 months, 4.77% at 12 months, 8.49% at 24 months and 12.07% at 36 months, significantly lower than conservative group: 10.50% at 3 months, 20.73% at 12 months, 31.96% at 24 months and 43.04% at 36 months. We found a substantially lower mortality (hazard ratio [HR] 0.34, 95% confidence internal, [CI]: 0.23-0.52, p = 0.000) among patients undergoing surgical therapy than those undergoing conservative therapy, even when controlled for gender, age, the length of hospital stay, and all the comorbidities. Female patients (HR 0.68, 95% CI: 0.58-0.79, p = 0.000) were less likely to die than male patients after an intertrochanteric fracture. Patients treated by the two methods were both found to have excess mortality rates compared to the general population, although in different levels. The excess mortality rates for patients in the conservative therapy group were 14.46% in males and 17.93% in females, while in the surgical therapy group, 2.78% in females and 4.37% in males. The comorbidities moderate or severe renal disease (HR 2.19, 95% CI: 1.61-2.98, p = 0.000), metastatic solid tumor (HR 6.35, 95% CI: 1.56-25.85, p = 0.010), hypoproteinemia (HR 1.22, 95% CI: 1.01-1.47, p = 0.034), and older age (HR 1.89, 95% CI: 1.73-2.08, p = 0.000) were also risk factors on mortality. A worse-case analysis for the primary outcome were performed as sensitivity analysis and it was consistent with the original conclusion. CONCLUSION: Intertrochanteric factures for people aged 50 years older were found to have excess mortality compared to the general population in Tianjin city, and preventing the fractures in the hip for elderly people was imperative. After controlling tfor comorbidities and age, female gender and surgical therapy were protective factors for the death after fractures, which could provide strong evidence for patients and surgeons to make decisions.


Asunto(s)
Fracturas de Cadera , Osteoporosis , Humanos , Anciano , Masculino , Femenino , Persona de Mediana Edad , Estudios de Cohortes , Estudios Retrospectivos , Comorbilidad , Resultado del Tratamiento
19.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(10): 1314-1318, 2023 Oct 15.
Artículo en Chino | MEDLINE | ID: mdl-37848329

RESUMEN

Objective: To summarize the influence of microstructure on performance of triply-periodic minimal surface (TPMS) bone scaffolds. Methods: The relevant literature on the microstructure of TPMS bone scaffolds both domestically and internationally in recent years was widely reviewed, and the research progress in the imfluence of microstructure on the performance of bone scaffolds was summarized. Results: The microstructure characteristics of TPMS bone scaffolds, such as pore shape, porosity, pore size, curvature, specific surface area, and tortuosity, exert a profound influence on bone scaffold performance. By finely adjusting the above parameters, it becomes feasible to substantially optimize the structural mechanical characteristics of the scaffold, thereby effectively preempting the occurrence of stress shielding phenomena. Concurrently, the manipulation of these parameters can also optimize the scaffold's biological performance, facilitating cell adhesion, proliferation, and growth, while facilitating the ingrowth and permeation of bone tissue. Ultimately, the ideal bone fusion results will obtain. Conclusion: The microstructure significantly and substantially influences the performance of TPMS bone scaffolds. By deeply exploring the characteristics of these microstructure effects on the performance of bone scaffolds, the design of bone scaffolds can be further optimized to better match specific implantation regions.


Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Huesos , Porosidad
20.
Orthop Surg ; 15(12): 3126-3135, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37853959

RESUMEN

OBJECTIVE: Previous studies have shown that bone mineral density (BMD) is a predictor of cage subsidence. Phantom-less quantitative computed tomography (PL-QCT) can measure volumetric bone mineral density (vBMD) of lumbar trabecular and cortical bone. The study of endplate vBMD (EP-vBMD) is important in predicting cage settlement after extreme lateral interbody fusion (XLIF). This study aimed to determine the risk factors for postoperative cage subsidence after XLIF, particularly focusing on the relationship between vBMD measured by automatic PL-QCT and cage subsidence. METHODS: Patients who underwent XLIF surgery from January 2018 to October 2020 with a minimum of 6 months of follow-up were retrospectively included. Cage subsidence was defined as >2 mm cage sinking on the adjacent endplate in follow-up imaging evaluation. Outcome measures were localized vBMDs included EP-vBMDs with different region of interest (ROI) heights measured by PL-QCT based on a customized muscle-fat algorithm. Shapiro-Wilk test, one-way ANOVA, Mann-Whitney test, Fisher exact test, univariable and multivariable logistic regression and receiver operating characteristic (ROC) curve analysis were executed in this study. RESULTS: One hundred and thirteen levels of 78 patients were included in the analysis. The mean age was 65 ± 7.9 years for 11 males and 67 females. Cage subsidence occurred on 45 (39.8%) surgical levels. There was no significant difference in demographics, fused levels, or preoperative radiographic parameters. 1.25-mm EP-vBMD (0.991 [0.985,0.997], p = 0.004) and P-TB-vBMD (cage-positioned trabecular volumetric bone mineral density) (0.988 [0.977-0.999], p = 0.026) were cage-subsidence relevant according to univariate analysis. Low 1.25-mm EP-vBMD (0.992 [0.985, 0.999], p = 0.029) was an independent risk factor according to multifactorial analysis. CONCLUSION: Preoperative low EP-vBMD was an independent risk factor for postoperative cage subsidence after XLIF. EP-vBMD measured by most cortex-occupied ROI may be the optimal vBMD parameter for cage subsidence prediction.


Asunto(s)
Densidad Ósea , Fusión Vertebral , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Tomografía Computarizada por Rayos X/métodos , Hueso Cortical
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