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2.
Nat Commun ; 15(1): 7920, 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-39256375

RÉSUMÉ

Global urbanization requires more stable and sustainable wastewater treatment to reduce the burden on the water environment. To address the problem of substrate inhibition of microorganisms during wastewater treatment, which leads to unstable wastewater discharge, this study proposes an approach to enhance the tolerance of bacterial community by artificially setting up a non-lethal high substrate environment. And the feasibility of this approach was explored by taking the inhibition of anammox process by nitrite as an example. It was shown that the non-lethal high substrate environment could enhance the nitrite tolerance of anammox bacterial community, as the specific anammox activity increasing up to 24.71 times at high nitrite concentrations. Moreover, the system composed of anammox bacterial community with high nitrite tolerance also showed greater resistance (two-fold) in response to nitrite shock. The antifragility of the system was enhanced without affecting the operation of the main reactor, and the non-lethal high nitrite environment changed the dominant anammox genera to Candidatus Jettenia. This approach to enhance tolerance of bacterial community in a non-lethal high substrate environment not only allows the anammox system to operate stably, but also promises to be a potential strategy for achieving stable biological wastewater treatment processes to comply with standards.


Sujet(s)
Bactéries , Bioréacteurs , Nitrites , Eaux usées , Purification de l'eau , Eaux usées/microbiologie , Eaux usées/composition chimique , Nitrites/métabolisme , Bactéries/métabolisme , Bactéries/effets des médicaments et des substances chimiques , Bactéries/génétique , Purification de l'eau/méthodes , Bioréacteurs/microbiologie , Élimination des déchets liquides/méthodes , Oxydoréduction
3.
Angew Chem Int Ed Engl ; : e202413115, 2024 Sep 24.
Article de Anglais | MEDLINE | ID: mdl-39317992

RÉSUMÉ

Two-dimensional conjugated metal-organic frameworks (2D c-MOFs) have shown great promise in various electrochemical applications due to their intrinsic electrical conductivity. A large pore aperture is a favorable feature of this type of material because it facilitates the mass transport of chemical species and electrolytes. In this work, we propose a ligand insertion strategy in which a linear ligand is inserted into the linkage between multitopic ligands, extending the metal ion into a linear unit of -M-ligand-M-, for the construction of 2D c-MOFs with large pore apertures, utilizing only small ligands. As a proof-of-concept trial of this strategy, a 2D c-MOF with mesopores of 3.2 nm was synthesized using commercially available ligands hexahydrotriphenylene and 2,5-dihydroxybenzoquinone. The facilitation of the diffusion of redox species by the large pore size of this MOF was demonstrated through a series of probes. With this feature, it showed superior performance in the electrochemical analysis of a variety of biological species.

5.
BMC Oral Health ; 24(1): 1079, 2024 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-39272063

RÉSUMÉ

OBJECTIVE: To investigate the current state of oral frailty in oldely patients with require dental implants, analyze influencing factors in the characteristics of oral frailty across different patient categories, and provide a reference for clinical staff to identify high-risk groups and develop proactive management strategies. METHODS: Between January 2024 and March 2024, 654 patients with dental implants were selected using convenience sampling from six secondary and tertiary stomatological hospitals in Jiangsu and Zhejiang provinces. Data were collected via a general information questionnaire and the Oral Frailty Index-8. The latent profiles of oral frailty were examined, and univariate and Logistic regression analyses were conducted to determine the impact of various factors on these profiles. RESULTS: In this cross-sectional study, 605 valid questionnaires were returned, yielding an effective rate of 92.58%. The mean oral frailty score was 6.64 ± 1.21, with the sample comprising 223 males and 382 females, averaging 72.54 ± 6.33 years old. Oral frailty was categorized into three latent profiles: high (20.50%), moderate (53.72%), and low (25.78%) frailty groups. Factor analysis indicated that age, gender, education level, family income, number of implants, and dyslipidemia significantly predicted the classification of these profiles (P < 0.05). CONCLUSION: Oral frailty in oldely patients with dental implants exhibits heterogeneity and is influenced by age, sex, education level, family income, number of implants, and dyslipidemia. Clinical staff should recognize the characteristics of different patient categories and implement proactive measures for those at high risk of oral frailty to enhance their quality of life.


Sujet(s)
Implants dentaires , Fragilité , Humains , Mâle , Femelle , Études transversales , Sujet âgé , Fragilité/complications , Enquêtes et questionnaires , Facteurs de risque , Sujet âgé de 80 ans ou plus , Chine , Adulte d'âge moyen , Personne âgée fragile , Facteurs âges
6.
ACS Biomater Sci Eng ; 2024 Sep 25.
Article de Anglais | MEDLINE | ID: mdl-39321210

RÉSUMÉ

In recent years, biological 3D printing has garnered increasing attention for tissue and organ repair. The challenge with 3D-printing inks is to combine mechanical properties as well as biocompatibility. Proteins serve as vital structural components in living systems, and utilizing protein-based inks can ensure that the materials maintain the necessary biological activity. In this study, we incorporated two natural biomaterials, silk fibroin (SF) and collagen (COL), into a low-concentration sodium alginate (SA) solution to create novel composite inks. SF and COL were modified with glycidyl methacrylate (GMA) to impart photo-cross-linking properties. The UV light test and 1H NMR results demonstrated successful curing of silk fibroin (SF) and collagen (COL) after modification and grafting. Subsequently, the printability of modified silk fibroin (RSFMA)/SA with varying concentration gradients was assessed using a set of three consecutive printing models, and the material's properties were tested. The research results prove that the addition of RSFMA and ColMA enhances the printability of low-concentration SA solutions, with the Pr values increasing from 0.85 ± 0.02 to 0.90 ± 0.03 and 0.92 ± 0.02, respectively, and the mechanical strength increasing from 0.19 ± 0.01 to 0.28 ± 0.01 and 0.38 ± 0.01 MPa; cytocompatibility has also been improved. Furthermore, rheological tests indicated that all of the inks exhibited shear thinning properties. CCK-8 experiments demonstrated that the addition of ColMA increased the cytocompatibility of the ink system. Overall, the utilization of SF and COL-modified SA materials as inks represents a promising advancement in 3D-printed ink technology.

7.
J Cardiothorac Surg ; 19(1): 546, 2024 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-39313784

RÉSUMÉ

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a family inherited cardiomyopathy associated with ventricular arrhythmias. With the development of molecular biology, histology, imaging, and other diagnostic techniques, the diagnosis rate and incidence of ARVC have gradually increased. However, ARVC remains rare in clinical practice. Currently, the diagnosis and management of ARVC is far from satisfactory in clinical practice. In the case report, we described a clinical case of radiofrequency ablation guided by voltage mapping and right ventriculography in the treatment of ARVC with ventricular tachycardia and discussed the relevant literatures.


Sujet(s)
Dysplasie ventriculaire droite arythmogène , Ablation par cathéter , Tachycardie ventriculaire , Humains , Dysplasie ventriculaire droite arythmogène/chirurgie , Dysplasie ventriculaire droite arythmogène/complications , Dysplasie ventriculaire droite arythmogène/diagnostic , Dysplasie ventriculaire droite arythmogène/imagerie diagnostique , Tachycardie ventriculaire/chirurgie , Tachycardie ventriculaire/physiopathologie , Ablation par cathéter/méthodes , Mâle , Ventricules cardiaques/imagerie diagnostique , Ventricules cardiaques/chirurgie , Électrocardiographie , Adulte
8.
Patient Prefer Adherence ; 18: 1803-1813, 2024.
Article de Anglais | MEDLINE | ID: mdl-39229369

RÉSUMÉ

Purpose: Discrete choice experiment (DCE) and profile case (case 2) best-worst scaling (BWS) present uncertainties regarding the acceptability of quantifying individual healthcare preferences, which may adversely affect the validity of responses and impede the reflection of true healthcare preferences. This study aimed to assess the acceptability of these two methods from the perspective of patients with type 2 diabetes mellitus (T2DM) and examine their association with specific characteristics of the target population. Patients and Methods: This cross-sectional study was based on a nationally representative survey; data were collected using a multistage stratified cluster-sampling procedure between September 2021 and January 2022. Eligible adults with confirmed T2DM voluntarily participated in this study. Participants completed both the DCE and case 2 BWS (BWS-2) choice tasks in random order and provided self-reported assessments of acceptability, including task completion difficulty, comprehension of task complexity, and response preference. Logistic regression and random forest models were used to identify variables associated with acceptability. Results: In total, 3286 patients with T2DM were included in the study. Respondents indicated there was no statistically significant difference in completion difficulty between the DCE and BWS-2, although the DCE scores were slightly higher (3.07 ± 0.68 vs 3.03 ± 0.67, P = 0.06). However, 1979 (60.2%) respondents found the DCE easier to comprehend. No significant preferences were observed between the two methods (1638 (49.8%) vs 1648 (50.2%)). Sociodemographic factors, such as residence, monthly out-of-pocket costs, and illness duration were significantly associated with comprehension complexity and response preference. Conclusion: This study yielded contrasting results to most of previous studies, suggesting that DCE may be less cognitively demanding and more suitable for patients with T2DM from the perspective of self-reported acceptability of DCE and BWS. This study promotes a focus on patient acceptability in quantifying individual healthcare preferences to inform tailored optimal stated-preference method for a target population.


Stated preference methodologies such as the discrete choice experiment (DCE) and case 2 best-worst scaling (BWS-2) are gaining popularity as methods for quantifying individual preferences in healthcare. However, the acceptability of the two methods to participants must be considered in practice to reduce cognitive burden and ensure the validity of preference elicitation.DCE was perceived to be less cognitively burdensome than BWS-2. In contrast to patients who thought that DCE was more acceptable, BWS-2 was more accepted by rural patients, patients who lived with the disease for a longer period, and those who had lower monthly out-of-pocket costs.These findings demonstrate potential differences in the acceptability of DCE and BWS-2 for patients with type 2 diabetes mellitus. To improve efficiency, it would be useful for researchers to consider the optimal stated preference method for identifying target populations according to sociodemographic and disease-related characteristics.

9.
J Hepatol ; 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39218228

RÉSUMÉ

BACKGROUND & AIMS: Frailty is associated with multiple morbidities. However, its effect on chronic liver diseases remains largely unexplored. This study evaluated the association of frailty with the risk of incident metabolic dysfunction-associated steatotic liver disease (MASLD), cirrhosis, liver cancer, and liver-related mortality. METHODS: A total of 339,298 participants without prior liver diseases from the UK Biobank were included. Baseline frailty was assessed by using physical frailty and the frailty index, categorizing participants as nonfrail, prefrail, or frail. The primary outcome was MASLD, with secondary outcomes, including cirrhosis, liver cancer, and liver-related mortality, confirmed through hospital admission records and death registries. RESULTS: During a median follow-up of 11.6 years, 4,667 MASLD, 1,636 cirrhosis, 257 liver cancer, and 646 liver-related mortality cases were identified. After multivariable adjustment, the risk of MASLD was found to be higher in participants with prefrailty (physical frailty: HR = 1.66, 95% CI = 1.40-1.97; frailty index: HR = 2.01, 95% CI = 1.67-2.42) and frailty (physical frailty: HR = 3.32, 95% CI = 2.54-4.34; frailty index: HR = 4.54, 95% CI = 3.65-5.66) than in those with nonfrailty. Similar results were also observed for cirrhosis, liver cancer, and liver-related mortality. Additionally, the frail groups had a higher risk of MASLD, which was defined as magnetic resonance imaging-derived liver proton density fat fraction > 5%, than the nonfrail group (physical frailty: OR = 1.64, 95% CI = 1.32-2.04; frailty index: OR = 1.48, 95% CI = 1.30-1.68). CONCLUSIONS: Frailty was associated with an increased risk of chronic liver diseases. Public health strategies should target reducing chronic liver disease risk in frail individuals. IMPACT AND IMPLICATIONS: While frailty is common and associated with a poor prognosis in people with MASLD and advanced chronic liver diseases, its impact on the subsequent risk of these outcomes remains largely unexplored. Our study showed that frailty was associated with the increased risks of MASLD, cirrhosis, liver cancer, and liver-related mortality. This finding suggests that assessing frailty may help identify a high-risk population vulnerable to developing chronic liver diseases. Implementing strategies that target frailty could have major public health benefits for liver-related disease prevention.

11.
Int J Biol Macromol ; 279(Pt 2): 135204, 2024 Aug 31.
Article de Anglais | MEDLINE | ID: mdl-39218182

RÉSUMÉ

The high polysaccharide content of Lycii fructus agri-food waste should be reclaimed for value liberation from both environmental and economic perspectives. In this study, waste from L. fructus pigment products was valorized on a bench scale by upcycling into active polysaccharide-rich extracts. The methodological feasibility of polysaccharide recovery from L. fructus waste was evaluated using sequential extraction techniques. Three fractions LFP-30, LFP-100, and LFP-121, were obtained under stepwise increases in temperature and pressure. Highly heterogeneous xyloglucan (XG)-pectin macromolecules composed of linear homogalacturonan (HG) and alternating intra-RG-I-linkers, with topological neutral branches and XG participation, were predominant among the L. fructus polysaccharides (LFPs). Antioxidant activities in LFPs were unaffected by waste resources and severe extraction methodology conditions. Additionally, the direct investment potential of polysaccharide recovery was evaluated for full-scale implementation. This study demonstrated the necessity and feasibility of extracting bioactive polysaccharides with potential applications from L. fructus waste, and provided a sustainable strategy for transforming L. fructus waste disposal problems into value-added products using cost-effective methodologies.

12.
Opt Lett ; 49(18): 5047-5050, 2024 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-39270226

RÉSUMÉ

We report on the efficient generation of intense terahertz radiation from the organic crystal N-benzyl-2-methyl-4-nitroaniline pumped by chirped Ti:sapphire femtosecond laser pulses. The THz energy and spectrum as a function of the pump fluence and duration of the chirped laser pulses are studied systematically. For the appropriate positively chirped pump pulses, a significant boost in the THz generation efficiency by a factor of around 2.5 is achieved, and the enhancement of high-frequency components (>1 THz) shortens the THz pulse duration. Via complete characterization of THz properties and transmitted laser spectra, this nonlinear behavior is attributed to the extended effective interaction length for phase matching as a result of the self-phase modulation of the intense pump laser pulses. Numerical calculations well reproduce the experimental observation. Our results demonstrate a robust, efficient, strong-field (up to several MV/cm) THz source using the common sub-10 mJ and sub-100 fs Ti:sapphire laser systems without optical parametric amplifiers.

13.
Molecules ; 29(17)2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39275019

RÉSUMÉ

To meet the demands for high-temperature performance and lightweight materials in aerospace engineering, the Au-Ni solder is often utilized for joining dissimilar materials, such as Ti3Al-based alloys and Ni-based high-temperature alloys. However, the interaction between Ti and Ni can lead to the formation of brittle phases, like Ti2Ni, TiNi, and TiNi3, which diminish the mechanical properties of the joint and increase the risk of crack formation during the welding process. Cu doping has been shown to enhance the mechanical properties and high-temperature stability of the Au-Ni brazed joint's central area. Due to the difficulty in accurately controlling the solid solution content of Cu in the Au-Ni alloy, along with the high cost of Au, traditional experimental trial-and-error methods are insufficient for the development of Au-based solders. In this study, first principles calculations based on density functional theory were employed to analyze the effect of Cu content on the stability of the Au-2.0Ni-xCu (x = 0, 0.25, 0.5, 0.75, 1.0, 1.25 wt%) alloy phase structure. The thermal properties of the alloy were determined using Gibbs software fitting. The results indicate that the Au-2.0Ni-0.25Cu alloy exhibits the highest plastic toughness (B/G = 5.601, ν = 0.416, Cauchy pressure = 73.676 GPa) and a hardness of 1.17 GPa, which is 80% higher than that of Au-2.0Ni. This alloy balances excellent strength and plastic toughness, meeting the mechanical performance requirements of brazed joints. The constant pressure specific heat capacity (Cp) of the Au-2.0Ni-xCu alloy is higher than that of Au-2.0Ni and increases with Cu content. At 1000 K, the Cp of the Au-2.0Ni-0.25Cu alloy is 35.606 J·mol-1·K-1, which is 5.88% higher than that of Au-2.0Ni. The higher Cp contributes to enhanced high-temperature stability. Moreover, the linear expansion coefficient (CTE) of the Au-2.0Ni-0.25Cu alloy at 1000 K is 8.76 × 10-5·K-1, only 0.68% higher than Au-2.0Ni. The lower CTE helps to reduce the risk of solder damage caused by thermal stress. Therefore, the Au-2.0Ni-0.25Cu alloy is more suitable for brazing applications in high-temperature environments due to its excellent mechanical properties and thermal stability. This study provides a theoretical basis for the performance optimization and engineering application of the Au-2.0Ni-xCu alloy as a gold-based solder.

14.
J Colloid Interface Sci ; 678(Pt C): 1-12, 2024 Sep 12.
Article de Anglais | MEDLINE | ID: mdl-39276683

RÉSUMÉ

Semiconductors, such as metal oxides and metal sulfides (MSX), are widely investigated as effectively catalytic materials to convert carbon dioxide (CO2) and water into chemicals under simulated solar light. These valuable investigations might address both the energy crisis and climate change in our modern society. Herein, a novel strategy to construct leaf-like heterojunctions of VS-ZnIn2S4/TiN-x is reported. The new semiconductor heterojunctions were then applied to photoelectrocatalytic CO2 reduction, achieving excellent performance (formate formation rate of 1173.2 µM h-1 cm-2) attributed to the plant cell-like morphology and enhanced electron mobility from the heterojunction interfaces to the active sites on the surface. Our findings suggest that titanium nitride (TiN) with good conductivity can improve the photoelectrocatalytic ability of MSX through heterojunction construction. The photocathode VS-ZnIn2S4/TiN-3 exhibits 81.0 % selectivity toward C2 products by optimizing the material structure and reaction conditions. According to the systematic investigation of operando Fourier transform infrared (FTIR) spectra, common intermediates such as *COO-, *COOH, *CO, *CHO, *COCHO, and *COCH3 reported in the literature were carefully verified. Among these, the carbene specie serve as the key intermediate responsible for generating other intermediates and resulting in all products.

15.
Pestic Biochem Physiol ; 204: 106082, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39277395

RÉSUMÉ

Bemisia tabaci poses a severe threat to plants, and the control of B. tabaci mainly relies on pesticides, which causes more and more rapidly increasing resistance. ß-Caryophyllene is a promising ingredient for agricultural pest control, but its feature of poor water solubility need to be improved in practical applications. Nanotechnology can enhance the effectiveness and dispersion of volatile organic compounds (VOCs). In this study, a nanoliposome carrier was constructed by ethanol injection and ultrasonic dispersion method, and ß-caryophyllene was wrapped inside it, thus solving the defect of poor solubility of ß-caryophyllene. The size of the ß-caryophyllene nanoliposomes (C-BT-NPs) was around 200 nm, with the absolute value of the zeta potential exceeding 30 mV and a PDI below 0.5. The stability was also maintained over a 14-d storage period. C-BT-NPs showed effective insecticidal activity against B. tabaci, with an LC50 of 1.51 g/L, outperforming thiamethoxam and offering efficient agricultural pest control. Furthermore, C-BT-NPs had minimal short-term impact on the growth of tomato plants, indicating that they are safety on plants. Therefore, the VOCs using nanoliposome preparation technology show promise in reducing reliance on conventional pesticides and present new approaches to managing agricultural pests.


Sujet(s)
Hemiptera , Insecticides , Liposomes , Sesquiterpènes polycycliques , Animaux , Hemiptera/effets des médicaments et des substances chimiques , Sesquiterpènes polycycliques/pharmacologie , Sesquiterpènes polycycliques/composition chimique , Insecticides/pharmacologie , Insecticides/composition chimique , Nanoparticules/composition chimique , Sesquiterpènes/pharmacologie , Sesquiterpènes/composition chimique , Solanum lycopersicum/parasitologie , Composés organiques volatils/composition chimique , Composés organiques volatils/pharmacologie
16.
Article de Anglais | MEDLINE | ID: mdl-39278622

RÉSUMÉ

OBJECTIVE: Understanding the intricate relationship between symptom dimensions, clusters, and cognitive impairments is crucial for early detection and intervention in individuals at clinical high-risk(CHR) for psychosis. This study delves into this complex interplay within a CHR sample and aims to predict the conversion to psychosis. METHODS: A comprehensive cognitive assessment was performed among 744 CHR individuals. The study included a three-year follow-up period to assess conversion to psychosis. Symptom profiles were determined using the Structured Interview for Prodromal Syndromes. By applying factor analysis, symptom dimensions were categorized as dominant negative symptoms(NS), positive symptoms-stressful(PS-S), and positive symptoms-odd(PS-O). The factor scores were used to define three dominant symptom groups. Latent class analysis(LCA) and factor mixture model(FMM) were employed to identify discrete clusters based on symptom patterns. The three-class solution was chosen for the LCA and FMM analysis. RESULTS: Individuals in the dominant NS group exhibited significantly higher conversion rates to psychosis than those in the other groups. Specific cognitive variables, including performance in the Brief Visuospatial Memory Test-Revised(Odd ratio, OR=0.702, p=0.001) and Neuropsychological Assessment Battery mazes(OR=0.776, p=0.024), significantly predicted conversion to psychosis. Notably, cognitive impairments associated with NS and PS-S affected different cognitive domains. LCA- and FMM-Cluster 1, characterized by severe NS and PS-O, exhibited more impairments in cognitive domains than other clusters. No significant difference in the conversion rate was observed among LCA and FMM clusters. CONCLUSIONS: These findings highlight the importance of NS in the development of psychosis and suggest specific cognitive domains that are affected by symptom dimensions.

17.
Anal Biochem ; 696: 115658, 2024 Sep 05.
Article de Anglais | MEDLINE | ID: mdl-39244003

RÉSUMÉ

A novel photoelectrochemical (PEC) biosensor was developed incorporating a specifically designed RNA aptamer for the detection of theophylline (TP). This involved utilizing two nucleotide base aptamers with tailored sequences designed to target TP. The 3' end of a single-stranded RNA sequence (5'-GGAUACCA-(CH2)6-SH-3') and the 5' end of a complementary stranded RNA sequence (5'-HS-(CH2)6-CCUUGGAAGCC-3') were linked to gold nanoparticles (AuNPs) and CdS quantum dots (QDs), respectively. These two single-stranded RNAs (ssRNA) formed a double-stranded RNA (dsRNA) capable of recognizing TP. This major structural change altered the spacing between QDs and NPs, which signaled the presence and concentration of TP. TP was photoelectrochemical catalytic oxidation by the hole of CdS QDs under illumination, then anode photocurrent was generated. Due to the increase in surface impedance and the effect of exciton energy transfer (EET) between QDs and AuNPs, the photocurrent would undergo varying degrees of change. TP was detected by changes in photocurrent. PEC detection of TP was achieved in the range of 0.1 µM-200 µM. The detection limit was 0.033 µM. The method exhibited commendable reproducibility and remarkable selectivity. The biosensor was used to measure TP content in tea, beverages and blood samples, resulting in satisfactory recovery rates.

18.
Angew Chem Int Ed Engl ; : e202411733, 2024 Aug 08.
Article de Anglais | MEDLINE | ID: mdl-39115949

RÉSUMÉ

Here we designed enantiomeric lipid-mimetic glutamic acid derivatives (L/D-UG) and investigated their self-assembled chiral nanostructures' interaction with the protein adsorption as well as the osteogenesis. It was found that L or D-UG molecules can self-assemble into vesicle bilayers and two-dimensional (2D) nanocrystals via a kinetic and thermodynamic control, respectively. These chiral vesicles and 2D crystals showed differentiated adsorption of proteins, determined by their curvature and chirality. Specifically, fibronectin constituted by L-amino acids adsorbed preferentially on L-UG 2D crystal in a semi-random pattern and L-2D nanocrystal show as the most effective structures to promote bone regeneration. The controlled vesicle and 2D crystal assemblies with different chirality and curvature helps to clarify their determine roles in protein adsorption and osteogenesis.

20.
Acta Orthop Traumatol Turc ; 58(2): 89-94, 2024 Apr 26.
Article de Anglais | MEDLINE | ID: mdl-39115800

RÉSUMÉ

This study aimed to compare the biomechanical performance of an intramedullary nail combined with a reconstruction plate and a single intramedullary nail in the treatment of unstable intertrochanteric femoral fractures with a fracture of the lateral femoral wall (LFW). A three-dimensional finite element (FE) femur model was established from computed tomography images of a healthy male volunteer. A major reverse obliquity fracture line, associated with a lesser trochanteric fragment defect and a free bone fragment of the LFW, was developed to create an AO/OTA type 31-A3.3 unstable intertrochanteric fracture mode. Two fixation styles were simulated: a long InterTAN nail (ITN) with or without a reconstruction plate (RP). A vertical load of 2100 N was applied to the femoral head to simulate normal walking. The construct stiffness, von Mises stress, and model displacement were assessed. The ITN with RP fixation (ITN/RP) provided higher axial stiffness (804 N/mm) than the ITN construct (621 N/mm). The construct stiffness of ITN/RP fixation was 29% higher than that of ITN fixation. The peak von Mises stress of the implants in the ITN/RP and ITN models was 994.46 MPa and 1235.24 MPa, respectively. The peak stress of the implants in the ITN/RP model decreased by 24% compared to that of the ITN model. The peak von Mises stress of the femur in the ITN/RP model was 269.06 MPa, which was lower than that of the ITN model (331.37 MPa). The peak stress of the femur in the ITN/RP model was 23% lower than that of the ITN model. The maximum displacements of the ITN/RP and ITN models were 12.12 mm and 13.53 mm, respectively. The maximum displacement of the ITN/RP model decreased by 12% compared with that of the ITN model. The study suggested that an additional plate fixation could increase the construct stiffness, reduce the stresses in the implant and femur, and decrease displacement after intramedullary nailing. Therefore, the intramedullary nail and reconstruction plate combination may provide biomechanical advantages over the single intramedullary nail in unstable intertrochanteric fractures with a fractured LFW.


Sujet(s)
Clous orthopédiques , Plaques orthopédiques , Analyse des éléments finis , Ostéosynthese intramedullaire , Fractures de la hanche , Humains , Ostéosynthese intramedullaire/méthodes , Ostéosynthese intramedullaire/instrumentation , Mâle , Phénomènes biomécaniques , Fractures de la hanche/chirurgie , Fractures du fémur/chirurgie , Tomodensitométrie/méthodes , Fémur/chirurgie
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