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1.
Mikrochim Acta ; 191(7): 437, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951284

RESUMO

A stable DNA signal amplification sensor was developed on account of rolling circle amplification (RCA). This sensor includes target DNA-controlled rolling circle amplification technology and locking probe DNA replacement technology, which can be used to detect DNA fragments with genetic information, thus constructing a biosensor for universal detection of DNA. This study takes the homologous DNA of human immunodeficiency virus (HIV) and let-7a as examples to describe this biosensor. The padlock probe is first cyclized by T4 DNA ligase in response to the target's reaction with it. Then, rolling cycle amplification is initiated by Phi29 DNA polymerase, resulting in the formation of a lengthy chain with several triggers. These triggers can open the locked probe LP1 with the fluorescence signal turned off, so that it can continue to react with H2 to form a stable H1-H2 double strand. This regulates the distance between B-DNA modified by the quenching group and H1 modified by fluorescent group, and the fluorescence signal is recovered.


Assuntos
Técnicas Biossensoriais , Sondas de DNA , Técnicas de Amplificação de Ácido Nucleico , Técnicas Biossensoriais/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Humanos , Sondas de DNA/química , Sondas de DNA/genética , Corantes Fluorescentes/química , DNA Viral/análise , DNA Viral/genética , DNA/química , DNA/genética , Espectrometria de Fluorescência/métodos , Fluorescência , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/química , Limite de Detecção , HIV/genética
2.
Adv Sci (Weinh) ; : e2404465, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995100

RESUMO

Low-dimensional lead halide perovskites demonstrate remarkable nonlinear optical characteristics attributed to their distinctive physical structures and electronic properties. Nevertheless, the investigation into their nonlinear optical properties remains in its incipient stages. This study addresses this gap by precisely controlling solvent volumes to synthesize both 0D Cs4PbBr6 and Cs4PbBr6/CsPbBr3 perovskites. Remarkably, as saturable absorbers, both pure Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites exhibit favorable nonlinear optical properties within the C-band, showcasing modulation depths of 9.22% and 16.83%, respectively. Moreover, for the first time, Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites have been successfully integrated into erbium-doped fiber lasers to realize the mode-locking operations. The utilization of the Cs4PbBr6/CsPbBr3 composites as a saturable absorber that enables the generation of conventional soliton mode-locked laser pulses with a pulse duration of 688 fs, and a repetition frequency of 10.947 MHz at a central wavelength of 1557 nm. Cs4PbBr6 is instrumental in generating laser pulses at a frequency of 10.899 MHz, producing pulse widths of 642 fs at the central wavelength of 1531.2 nm and 1.02 ps at the central wavelength of 1565.3 nm, respectively. The findings of this investigation underscore the potential utility of 0D Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites as promising materials for optical modulation within fiber laser applications.

3.
Ergonomics ; : 1-17, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023126

RESUMO

Car-lock sounds are designed to inform the lock status of vehicles. However, drivers often experience a lack of confidence regarding whether the car is locked, and car thefts persistently occur, frequently attributed to unlocked doors. Without identification of critical factors for evaluating effects of car-lock sounds on drivers, a strategy to car-lock sound design with increased locking efficiency remains implicit. This study proposes a method to identify critical factors influencing drivers' perceived certainty of car-lock status and behaviours during car-locking. An experiment was conducted to simulate the locking process and verbal protocol analysis was employed to comprehend participants' cognitive processes and behaviours. The results show that mechanical sound yielded high certainty and few hesitations, while tonal and crisp sound elicited low certainty and frequent hesitations. Seven critical factors on participants' behaviours and cognitive processes were identified, which provides a data-driven approach for future research in car-lock sounds evaluation and design.


The effect of car-lock sounds on drivers is significant to inform the locking status of vehicles. However, the strategy for car-lock sounds evaluation remains implicit. This study proposes a method to identify critical factors on drivers' behaviours and cognitive processes that would inform further car-lock sounds evaluation and design.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39013007

RESUMO

In this study, we investigate the spin-momentum locking phenomenon on Rashba states of antimony (Sb) films. Utilizing spin pumping in conjunction with an external charge current, we uncover the topological properties of Sb surface states. Our key finding is the precise manipulation of the direction and magnitude of the charge current generated by the inverse Rashba-Edelstein effect. This control is achieved through the dynamic interaction between out-of-equilibrium pumped spins and spin-momentum-locked flowing spins, which are perpendicular to the charge current. Our results highlight Sb as a promising material for both fundamental and applied spintronics research. The studied Sb nanostructures demonstrate potential for the development of low-power logic gates operating with currents in the microampere range, paving the way for advanced spintronic applications.

5.
Cureus ; 16(6): e62165, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38993466

RESUMO

AIM: Volar locking plates designed for far distal radius fracture fixation can have a significant hardware removal rate and risk of tendon rupture. Plate design has a role in the rate of complications. This study assessed the hardware removal and tendon rupture rate of the Acu-Loc 2 volar distal radius (VDR) plate often used in the treatment of far distal radial fractures. METHOD: We searched our electronic healthcare records system for all patients who had undergone fixation with an Acu-Loc 2 VDR plate (Acumed, Hillsboro, OR, USA) at a tertiary center between January 2017 and December 2021. Patients were excluded if their follow-up time was less than one year or if they could not be contacted by telephone follow-up. Pre-operative radiographs were examined for fracture classification. Follow-up time was defined as the last contact in the clinic or by telephone. RESULTS: A total of 92 patients underwent an open reduction and internal fixation (ORIF) with an Acu-Loc 2 VDR plate. A total of 85 patients met the inclusion criteria for this study. Our cohort included 33 males (38.8%) and 52 females (61.2%). The mean age was 50 years. Twenty-seven fractures (31.0%) were extra-articular, and 60 fractures (69.0%) were intra-articular. The mean follow-up time for the patients was 593.3 days (range 369 to 1185 days). Four patients (4.7%) had their hardware removed. Three (3.5%) patients underwent removal due to tendon irritation and one patient (1.2%) due to a peri-prosthetic fracture around the plate. There were no tendon ruptures recorded. CONCLUSION: The Acu-Loc 2 VDR plate had a low medium-term hardware removal rate and no tendon ruptures. These rates are lower than would be expected when compared with other far distal plate designs.

6.
J Clin Med ; 13(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38999516

RESUMO

Background/Objectives: Intramedullary screw fixation (IMS) and locking plate fixation (LPF) are currently recommended treatments for proximal fifth metatarsal fractures (PFMF). However, treating comminuted or small displaced avulsion PFMF with IMS poses challenges due to complications. A novel alternative fixation method, the locking compression plate for distal ulna hook plate fixation (LPF), has been introduced recently for distal ulna fractures and has shown improved clinical results. This scoping review aims to assess whether LPF yields superior outcomes, such as postoperative AOFAS scores and rate of postoperative complications, compared to IMS in PFMF treatment. Methods: This review included randomized controlled trials (RCTs), prospective cohort studies, retrospective cohort studies, or case series involving patients with PFMF who underwent plate fixation or screw fixation. The primary outcome was the postoperative American Orthopedic Foot and Ankle Society (AOFAS) score. Studies were sourced from databases including PubMed, Embase, and Scopus, with the search conducted up to February 2024. The Systematic Review protocol was registered in the CRD PROSPERO database (CRD42024532593). Results: Ten studies were included, comprising 3 cohort studies, 1 case-control study, and 6 case series, with a total of 309 patients (158 with LPF and 142 with IMS). The postoperative AOFAS scores showed no significant difference between LPF and IMS in treating PFMF. However, LPF demonstrated efficient surgical procedures and enhanced functional outcomes. Complications were minimal in both groups, with no significant difference in the rate of postoperative complications. Conclusions: Although there was no significant difference in AOFAS scores between LPF and IMS, LPF demonstrated efficient surgical procedures and enhanced functional outcomes, making it a reasonable alternative method for PFMF. Effective shared decision-making (SDM) with patients becomes paramount in choosing the optimal surgical approach. In the surgical landscape, thoughtful deliberation, patient engagement, and adherence to biomechanical principles are crucial for achieving successful outcomes in the treatment of PFMF.

7.
Small ; : e2404202, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39036839

RESUMO

As the highly stable and abundant carbon source in nature, the activation and conversion of CO2 into high-value chemicals is highly desirable yet challenging. The development of Cu(I)/Cu(II)─N tri-site synergistic single-atom catalysts (TS-SACs) with remarkable CO2 activation and conversion performance is presented, eliminating the need for external additives in cascade reactions. Under mild conditions (40 °C, atmospheric CO2), the catalyst achieves high yields (up to 99%) of valuable 2-oxazolidinones from CO2 and propargylamine. Notably, the catalyst demonstrates easy recovery, short reaction times, and excellent tolerance toward various functional groups. Supported by operando techniques and density functional theory calculations, it is elucidated that the spatially proximal Cu(I)/Cu(II)─N sites facilitate the coupling of multiple chemical transformations. This surpasses the performance of supported isolated Cu(I) or Cu(II) catalysts and traditional organic base-assisted cascade processes. These Cu(I)/Cu(II)─N tri-site synergistic atom active sites not only enable the co-activation of CO2 at the Cu(II)─N pair and alkyne at the Cu(I) site but also induce a di-metal locking geometric effect that accelerates the ring closure of cyclic carbamate intermediates. The work overcomes the limitations of single metal sites and paves the way for designing multisite catalysts for CO2 activation, especially for consecutive activation, tandem, or cascade reactions.

8.
Front Netw Physiol ; 4: 1399352, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962160

RESUMO

Physiological networks are usually made of a large number of biological oscillators evolving on a multitude of different timescales. Phase oscillators are particularly useful in the modelling of the synchronization dynamics of such systems. If the coupling is strong enough compared to the heterogeneity of the internal parameters, synchronized states might emerge where phase oscillators start to behave coherently. Here, we focus on the case where synchronized oscillators are divided into a fast and a slow component so that the two subsets evolve on separated timescales. We assess the resilience of the slow component by, first, reducing the dynamics of the fast one using Mori-Zwanzig formalism. Second, we evaluate the variance of the phase deviations when the oscillators in the two components are subject to noise with possibly distinct correlation times. From the general expression for the variance, we consider specific network structures and show how the noise transmission between the fast and slow components is affected. Interestingly, we find that oscillators that are among the most robust when there is only a single timescale, might become the most vulnerable when the system undergoes a timescale separation. We also find that layered networks seem to be insensitive to such timescale separations.

9.
J Exp Orthop ; 11(3): e12088, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38974053

RESUMO

Purpose: This paper investigates the biomechanical benefits of using hybrid constructs that combine cannulated screws with tension band wiring (TBW) cerclage compared to cannulated screws with anterior Variable Angle locking neutralisation plates (VA LNP). These enhancements can bear heavier loads and maintain the repaired patella's integrity, in contrast to traditional methods. Method: Eighteen fresh-frozen human cadaver patellae were carefully fractured transversely at their midpoints using a saw. They were then divided into two groups of nine for subsequent utilisation. Fixation methods included Cannulated Screw Fixation added with either TBW or VA LNP Fixation Technique. Cyclic loading simulations (500 cycles) were conducted to mimic knee motion, tracking fracture displacement with Optotrak. After that, the constructs were secured over a servo-hydraulic testing machine to determine the load-to-failure on axial mode. Results: The average fracture displacement for the anterior neutralisation plate group was 0.09 ± 0.12 mm, compared to 0.77 ± 0.54 mm for the tension band wiring with cannulated screw group after 500 cyclic loading. This result is statistically significant (p = 0.004). The anterior neutralisation plate group exhibited a mean load-to-failure of 1359 ± 21.53 N, whereas the tension band wiring group showed 780.1 ± 22.62 N, resulting in a significant difference between the groups (p = 0.007). Conclusion: This research highlights the superior biomechanical advantage of VA LNP over TBW for treating simple transverse patella fractures with two cannulated screws. It also highlights how the TBW is still a valuable option considering the load-to-failure limit. Level of Evidence: Not Applicable.

10.
Injury ; 55(10): 111718, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38986196

RESUMO

OBJECTIVES: This study compared outcomes of locked plating (LP) versus intramedullary nailing (IMN) techniques for treatment of extra-articular proximal-third tibia fractures. METHODS: Data Sources: PubMed, Ovid MEDLINE STUDY SELECTION: Studies were included if they compared LP and IMN fixation for proximal one third tibial shaft fractures without articular extension or with simple articular extension into the tibial plateau. Minimum 1 year of clinical and radiographic follow up was used. DATA EXTRACTION: Outcomes assessed included operative duration, postoperative knee range of motion (ROM), union outcomes (time to union, nonunion, malunion, delayed union), and incidence of postoperative complications (superficial and deep infection, secondary surgical intervention, compartment syndrome). DATA SYNTHESIS: Separate random-effects meta-analyses were conducted for each outcome. For categorical data, relative risks were used whereas the standardized mean difference was used for continuous variables, with corresponding 95 % confidence intervals. RESULTS: 7 studies were included reporting the outcomes of 319 patients treated with LP and 300 treated with IMN. IMN fixation had significantly shorter time to union (p = 0.049) and lower risk for superficial infection (p = 0.028). However, LP conferred a significantly lower risk for malunion (p = 0.017) and postoperative compartment syndrome (p = 0.018). CONCLUSION: IMN demonstrated significantly shorter time to union and lower risk of superficial infection when treating extra-articular proximal tibia fractures, while LP fixation demonstrated significantly lower risk for malunion and postoperative compartment syndrome. Although successful results can be achieved with good technique in LP and IMN fixation, a significant complication profile exists with these fractures regardless of construct choice. LEVEL OF EVIDENCE: Therapeutic Level III.

11.
J West Afr Coll Surg ; 14(3): 324-330, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988428

RESUMO

Introduction: Non-union is a complex, multifactorial orthopaedic problem that requires multiple treatment modalities for its management. It can result from infection, segmental bone loss, soft-tissue loss, and associated host factors. External fixators as management of gap non-union are bulky and give rise to a number of complications In our study, we have described a technique where we have used extramedullary fixation in the form of a tibial locking plate and transportation of part of the tibial bone after corticotomy by a monorail fixator. Materials and Methods: The procedure was done in two stages where internal and external fixation was done after creating a gap at the non-union site. The bone was transported after corticotomy and fixed to the internal fixation device in the second stage. The external fixator was removed in the second stage and the patient was then followed up till the bony union. The evaluation was done by functional and radiological assessment along with the complications noted with the described procedure. Results: Ten patients were enrolled in the study with a mean age of 33 years. The mean age of the patients was 33.7 ± 11.32 years with a mean size of the defect was 4.8 ± 1.7 cm. At 30 weeks out of nine patients, three patients had excellent and six had good functional results on the Association of Surgeons for Application and Methodology of Ilizarov (ASAMI) scale. The composite Musculoskeletal Tumor Society (MSTS) score was 76.66 % at the end of 30 weeks of follow-up. The mean time of consolidation was 134.4 days, whereas the mean union time was 145 days from index surgery. Ankle stiffness was the most common complication affecting 50% of the patients. Following closely was pin tract infection, which was present in 40% of the patients. According to Paley's classification, there were 11 obstacles, two problems and none were true complications. Conclusion: The integrated fixation is both safe and effective and has the advantage of early removal of the external fixator and a low complication rate as compared to use of a bulky conventional fixator alone. Moreover, it gives protection to the regenerated bone for a long period. So, this technique can be recommended for the management of segmental tibial defects.

12.
Physiol Behav ; 284: 114630, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971571

RESUMO

Working memory (WM) is a cognitive system with limited capacity that can temporarily store and process information. The purpose of this study was to investigate functional connectivity based on phase synchronization during WM and its relationship with the behavioral response. In this regard, we recorded EEG/Eye tracking data of seventeen healthy subjects while performing a memory-guided saccade (MGS) task with two different positions (near eccentricity and far eccentricity). We computed saccade error as memory performance and measured functional connectivity using Phase Locking Value (PLV) in the alpha frequency band (8-12 Hz). The results showed that PLV is negatively correlated with saccade error. Our finding indicated that during the maintenance period, PLV between the frontal and visual area in trials with low saccade error increased significantly compared to trials with high saccade error. Furthermore, we observed a significant difference between PLV for near and far conditions in the delay period. The results suggest that PLV in memory maintenance, in addition to predicting saccade error as behavioral performance, can be related to the coding of spatial information in WM.

13.
J Orthop Surg Res ; 19(1): 410, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39014468

RESUMO

BACKGROUND: The minimally invasive approach for the treatment of displaced scapular neck or body fractures has the advantages of less trauma and minimal muscle dissection. In clinical practice, the minimally invasive approach combined with an anatomical locking plate has been used to treat scapular body fractures. In addition, we have made minor modifications to the minimally invasive approach. However, the biomechanical study about the approach combined with an anatomical locking plate in treating scapular body fractures was limited. METHODS: Finite element analysis (FEA) was used to conduct the biomechanical comparison between the anatomical locking plate (AP model) and reconstructive plate (RP model) in the treatment of scapular body fractures through the modified minimally invasive approach. A healthy male volunteer with no history of scapula or systemic diseases was recruited. High-resolution computed tomography images of his right scapula were obtained. Two scapula models were constructed and analyzed by the software of Mimics 21.0, Geomagic Wrap 2021, SolidWorks 2021, and ANSYS Workbench 2022, respectively. RESULTS: Through static structural analysis, in terms of equivalent von Mises stress, equivalent elastic strain, and total deformation, the AP model exhibited superior safety characteristics, enhanced flexibility, and anticipated stability compared with the RP model. This was evidenced by lower maximum stress, lower maximum strain and displacement. CONCLUSION: The minimally invasive approach combined with an anatomical locking plate for scapular body fractures had better biomechanical stability. The study provided a biomechanical basis to guide the clinical treatment of scapular body fractures.


Assuntos
Placas Ósseas , Análise de Elementos Finitos , Fixação Interna de Fraturas , Fraturas Ósseas , Procedimentos Cirúrgicos Minimamente Invasivos , Escápula , Humanos , Escápula/lesões , Escápula/cirurgia , Escápula/diagnóstico por imagem , Masculino , Fraturas Ósseas/cirurgia , Fraturas Ósseas/diagnóstico por imagem , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fenômenos Biomecânicos , Adulto , Tomografia Computadorizada por Raios X
14.
Acta Pharm Sin B ; 14(7): 3251-3265, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39027238

RESUMO

Selective activation of Pt(IV) prodrugs within tumors has emerged as a promising strategy in tumor treatment. Although progress has been made with photo- and ultrasound-activated Pt(IV) prodrugs, concerns remain over the non-specific activation of photosensitizers (PS) and the potential for phototoxicity and chemical toxicity. In this study, a sequential dual-locked Pt(IV) nano-prodrug that can be activated by both the acidic tumor microenvironment and light was developed. The Pt(IV) prodrug was prepared by conjugating PS-locked Pt(IV) to a polymeric core, which was then chelated with metallo iron to lock its photoactivity and form a metallo-nano prodrug. Under acidic tumor microenvironment conditions, the metallo-nano prodrug undergoes dissociation of iron, triggering a reduction process in oxaliplatin under light irradiation, resulting in the activation of both chemotherapy and photodynamic therapy (PDT). Additionally, the prodrug could induce metallo-triggered ferroptosis and polarization of tumor-associated macrophages (TAM), thereby enhancing tumor inhibition. The dual-lock strategy employed in a nanoparticle delivery system represents an expansion in the application of platinum-based anticancer drugs, making it a promising new direction in cancer treatment.

15.
Hum Brain Mapp ; 45(11): e26787, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39023178

RESUMO

Regular cannabis use is associated with cortex-wide changes in spontaneous and oscillatory activity, although the functional significance of such changes remains unclear. We hypothesized that regular cannabis use would suppress spontaneous gamma activity in regions serving cognitive control and scale with task performance. Participants (34 cannabis users, 33 nonusers) underwent an interview regarding their substance use history and completed the Eriksen flanker task during magnetoencephalography (MEG). MEG data were imaged in the time-frequency domain and virtual sensors were extracted from the peak voxels of the grand-averaged oscillatory interference maps to quantify spontaneous gamma activity during the pre-stimulus baseline period. We then assessed group-level differences in spontaneous and oscillatory gamma activity, and their relationship with task performance and cannabis use metrics. Both groups exhibited a significant behavioral flanker interference effect, with slower responses during incongruent relative to congruent trials. Mixed-model ANOVAs indicated significant gamma-frequency neural interference effects in the left frontal eye fields (FEF) and left temporoparietal junction (TPJ). Further, a group-by-condition interaction was detected in the left FEF, with nonusers exhibiting stronger gamma oscillations during incongruent relative to congruent trials and cannabis users showing no difference. In addition, spontaneous gamma activity was sharply suppressed in cannabis users relative to nonusers in the left FEF and TPJ. Finally, spontaneous gamma activity in the left FEF and TPJ was associated with task performance across all participants, and greater cannabis use was associated with weaker spontaneous gamma activity in the left TPJ of the cannabis users. Regular cannabis use was associated with weaker spontaneous gamma in the TPJ and FEF. Further, the degree of use may be proportionally related to the degree of suppression in spontaneous activity in the left TPJ.


Assuntos
Cognição , Ritmo Gama , Magnetoencefalografia , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Ritmo Gama/fisiologia , Cognição/fisiologia , Mapeamento Encefálico , Testes Neuropsicológicos , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Uso da Maconha
16.
ACS Nano ; 18(29): 19099-19109, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39001858

RESUMO

Polarization plays a paramount role in scaling the optical network capacity. Anisotropic two-dimensional (2D) materials offer opportunities to exploit optical polarization-sensitive responses in various photonic and optoelectronic applications. However, the exploration of optical anisotropy in fiber in-line devices, critical for ultrafast pulse generation and modulation, remains limited. In this study, we present a fiber-integrated device based on a single-crystalline tellurene nanosheet. Benefiting from the chiral-chain crystal lattice and distinct optical dichroism of tellurene, multifunctional optical devices possessing diverse excellent properties can be achieved. By inserting the in-line device into a 1.5 µm fiber laser cavity, we generated both linearly polarized and dual-wavelength mode-locking pulses with a degree of polarization of 98% and exceptional long-term stability. Through a twisted configuration of two tellurene nanosheets, we realized an all-optical switching operation with a fast response. The multifunctional device also serves as a broadband photodetector. Notably, bipolar polarization encoding communication at 1550 nm can be achieved without any external voltage. The device's multifunctionality and stability in ambient environments established a promising prototype for integrating polarization as an additional physical dimension in fiber optical networks, encompassing diverse applications in light generation, modulation, and detection.

17.
Cureus ; 16(6): e62777, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39036152

RESUMO

Introduction Managing distal tibia fractures is challenging for trauma surgeons because of their peculiar anatomy with less soft tissue coverage and poor blood supply. There are various treatment options for distal tibia fractures such as open reduction and plating, minimally invasive percutaneous plate osteosynthesis, and intramedullary interlocking nailing. Open reduction and internal fixation can lead to excessive soft tissue dissection and devascularization of fracture fragments. We conducted a study on the functional outcome of distal tibia fractures treated by biological fixation with minimally invasive percutaneous plate osteosynthesis. Methods A total of 23 patients with distal one-third tibia fractures, fulfilling the inclusion criteria, who were treated at St. John's Medical College Hospital with minimally invasive percutaneous plate osteosynthesis between November 2020 and November 2022 were studied using the American Orthopaedic Foot & Ankle Society (AOFAS) score at six weeks, three months, and six months postoperative follow-up. Results This study included 17 males and six females. The mean age of the study participants was 43.78 years, with most of the participants being in the age group between 51 and 60 years (29.2%, n = 7). All the study participants were employed. The mean operative time was two hours and 10 minutes. The mean duration for the radiological union was 22 weeks. The mean AOFAS score at six months was 92.43 + 5.696. There was only one case of superficial infection, which was treated with intravenous antibiotics. There were no cases of malunion/nonunion. Conclusion Minimally invasive percutaneous plate osteosynthesis is an effective treatment for distal tibia fractures avoiding most of the complications such as wound dehiscence and malunion/nonunion involved in conventional open reduction and internal fixation with plating. Therefore, we recommend this technique for all distal tibia fractures.

18.
J Clin Orthop Trauma ; 53: 102439, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39036509

RESUMO

Introduction: Distal fibula osteoporotic comminuted fractures are challenging to treat and are often treated with periarticular locking plates. This study examined the biomechanical difference between locked plating and dual non-locked one-third tubular plating. Methods: Using an osteoporotic Sawbones fibula model, simulated fracture were fixated with one-third tubular dual plating and locked periarticular plating. The samples were then torqued to failure and peak torque, stiffness, and displacement were recorded. Results: The peak torque of the dual plating group was found to be statistically higher than the periarticular locked plating group (0.841 Nm and 0.740 Nm respectively; p = 0.024). However overall stiffness calculated at each 10° increment of displacement was noted to have no significant difference between the two constructs. Conclusion: Dual non-locked plating of distal fibula osteoporotic comminuted fractures is biomechanically equivalent to locked periarticular plating.

19.
Clin Biomech (Bristol, Avon) ; 117: 106296, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38936291

RESUMO

BACKGROUND: This study experimentally validated a computationally optimized screw number and screw distribution far cortical locking distal femur fracture plate and compared the results to traditional implants. METHODS: 24 artificial femurs were osteotomized with a 10 mm fracture gap 60 mm proximal to the intercondylar notch. Three fixation constructs were used. (i) Standard locking plates secured with three far cortical locking screws inserted according to a previously optimized distribution in the femur shaft (n = 8). (ii) Standard locking plates secured with four standard locking screws inserted in alternating plate holes in the femur shaft (n = 8). (iii) Retrograde intramedullary nail secured proximally with one anterior-posterior screw and distally with two oblique screws (n = 8). Axial hip forces (700 and 2800 N) were applied while measuring axial interfragmentary motion, shear interfragmentary motion, and overall stiffness. FINDINGS: Experimental far cortical locking plate results compared well to published computational findings. Far cortical locking femurs contained the highest axial motion within the potential ideal range of 0.2-1 mm and a sheer-to-axial motion ratio < 1.6 at toe-touch weight-bearing (700 N). At full weight-bearing (2800 N), Standard locking-plated femurs had the only axial motion within 0.2-1 mm but had an excess shear-to-axial motion ratio. Nail-implanted femurs underperformed at both forces. INTERPRETATION: For toe-touch weight-bearing, the far cortical locking construct provided optimal biomechanics to allow moderate motion, which has been suggested to encourage early callus formation. Conversely, at full weight-bearing, the standard locking construct offered the biomechanical advantage on fracture motion.


Assuntos
Placas Ósseas , Parafusos Ósseos , Fraturas do Fêmur , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/fisiopatologia , Humanos , Fenômenos Biomecânicos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Fêmur/cirurgia , Fêmur/fisiopatologia , Simulação por Computador , Suporte de Carga , Estresse Mecânico , Desenho de Prótese , Fraturas Femorais Distais
20.
Adv Mater ; : e2405511, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923158

RESUMO

In adhesive industry, tapes are renowned for their superior flexibility, repeatability, and ease of storage compared to glues. However, conventional adhesive tapes often suffer from low adhesion strength (<500 kPa). This work introduces an innovative adhesive tape composed of an amphiphilic copolymer and a hydrophobic ionic liquid, achieving an ultrahigh adhesion strength of up to 3.1 MPa on various substrates, making a record-high strength to date for tape-type adhesives. This exceptional adhesion performance is facilitated by water droplets applied at the bonding interface, transforming the adhesive surface into a glue-like property without the need for curing treatments or additional auxiliary equipment. By combining the advantageous features of both glues and tapes, these adhesives are termed as transient semi-glue tapes (TSGT). The mechanism behind such water activation and self-locking process is elucidated, and a general preparation approach is developed. Furthermore, the repeatability and recyclability of TSGT are demonstrated, offering an ingenious solution to this long-standing engineering challenge.

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