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1.
BMC Musculoskelet Disord ; 25(1): 764, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39354465

ABSTRACT

BACKGROUND: The evaluation of lateral ankle laxity remains challenging when diagnosing chronic lateral ankle instability (CLAI). Several studies have reported that internal rotation of the talus as an indicator of rotational lateral ankle laxity (RLAL) increases in patients with CLAI. However, there is no established method for detecting and evaluating the RLAL. This study aimed to report a novel method for evaluating the RLAL in the gravity stress position by measuring the talofibular distance (TFD) using ultrasonography (US) and show the normative value of the TFD. METHODS: The TFDs in the subjects with healthy ankles were prospectively measured 10 mm distal to the ankle joint in the neutral ankle position and gravity stress position using US. The differences in the TFD between the two ankle positions were evaluated. The differences in the TFD by gender and ankle laterality were also evaluated. RESULTS: A total of 52 healthy ankles of 28 subjects (mean age, 24.0 ± 1.6; male/female, 12/16) were finally included. There was a significant difference in the TFD between the neutral ankle position (6.9 ± 0.9 mm) and gravity stress position (9.0 ± 0.9 mm) (p < 0.001). The mean difference in the TFD between the two ankle positions was 2.1 ± 0.6 mm. There were no significant differences in the TFD by gender and ankle laterality. CONCLUSIONS: The present study reported a novel US method for evaluating RLAL by applying gravity stress and the normative value of the TFD.


Subject(s)
Ankle Joint , Joint Instability , Ultrasonography , Humans , Female , Male , Ankle Joint/diagnostic imaging , Ultrasonography/methods , Joint Instability/diagnostic imaging , Joint Instability/physiopathology , Young Adult , Adult , Prospective Studies , Rotation , Gravitation , Healthy Volunteers , Range of Motion, Articular/physiology , Reference Values , Lateral Ligament, Ankle/diagnostic imaging
2.
J Sports Sci ; 42(15): 1439-1452, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39259820

ABSTRACT

The objective of this study was to evaluate the effect of skill modifications on head motion experienced during women's artistic gymnastics skills. Nine gymnasts (four beginner and five advanced) completed three trials of up to 24 skill progressions, each consisting of a skill and two progressive safety modifications. Gymnasts were instrumented with mouthpiece sensors embedded with an accelerometer and gyroscope collecting motion data at 200, 300, and 500 Hz during each skill performance. Peak-to-peak linear and rotational kinematics during contact phases and peak rotational kinematics during non-contact phases were computed. A mixed-effects model was used to compare differences in modification status nested within skill categories. Timer skills (i.e. drills that simulate performance of a gymnastics skill) resulted in the highest median ΔLA and ΔRA of all skill categories, and 132 skill performances exceeded 10 g ΔLA during a contact phase. Modifications were associated with significant reductions in head kinematics during contact phases of timers, floor skills, bar releases, and vault skills. Gymnasts can be exposed to direct and indirect head accelerations at magnitudes consistent with other youth contact sports, and common safety modifications may be effective at reducing head motion during contact and non-contact phases of gymnastics skills.


Subject(s)
Acceleration , Gymnastics , Humans , Gymnastics/physiology , Biomechanical Phenomena , Female , Adolescent , Safety , Child , Rotation , Accelerometry/instrumentation , Head/physiology , Time and Motion Studies , Motor Skills/physiology , Sports Equipment , Head Movements/physiology
3.
J Chem Inf Model ; 64(17): 6857-6865, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39246057

ABSTRACT

As a critical sensor protein, NLRP3 detects cellular perturbation caused by diverse exogenous and endogenous stimuli. NLRP3 activation requires domain rotation within the NEK7-bound NLRP3 monomer and assembly. However, a detailed molecular mechanism for NLRP3 assembly and activation remains elusive, particularly in terms of dynamics and energetics. In this work, all-atom molecular dynamics (MD) simulations are executed to describe large-amplitude closed-to-open conformational transitions along the rotational pathway. From the MD trajectories, the computed potential of mean force (PMF) shows that NLRP3 activation through monomeric domain rotation is an uphill process, during which the active conformation of the NLRP3-NEK7 monomer cannot be stabilized. Further binding free-energy calculations for two neighboring NLRP3-NEK7 subunits in a disc assembly with the C10 symmetry reveal that the protein self-assembly starts approximately at the 86.5° position on the rotary pathway, along which the NLRP3 activation becomes a downhill process to the active state at 90.5°. The active NLRP3-NEK7 monomeric conformation in the disc assembly is stabilized because of the interactions between the neighboring subunits, involving mainly FISNA loop 1 in one subunit and a "crocodile-clip" structure formed by the NBD helix-loop-strand motif (residues 351-373) and the WHD ß-hairpin loop (residues 501-521) in the other. Our simulations also demonstrate that NEK7 plays an important role in the NLRP3 cage dissociation in the centrosome, which is consistent with biological experiments. The computational results provide kinetic, energetic, and structural insights into the molecular mechanisms of the activation of NLRP3 and the NEK7-driven dissociation of inactive NLRP3 cages. The activation mechanism of NLRP3 proposed in this work is significantly different from those of previous structural studies.


Subject(s)
NLR Family, Pyrin Domain-Containing 3 Protein , Humans , Molecular Dynamics Simulation , NIMA-Related Kinases/metabolism , NIMA-Related Kinases/chemistry , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/chemistry , Protein Binding , Protein Conformation , Protein Multimerization , Rotation , Thermodynamics
4.
Clin Oral Investig ; 28(10): 539, 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39304571

ABSTRACT

BACKGROUND: Optimization of a modified rotation advancement technique is hampered by lack of objective measures to quantify the longitudinal surgical outcome. METHODS: We collected and assessed facial 3D images of 115 consecutive patients who underwent primary repair between 2017 and 2019. Photogrammetry was performed preoperatively, immediately postoperatively and at a first and second follow-up interval, occurring at an average year of 0.6 and 5.3 years, respectively. 10 additional age-matched noncleft control subjects were also included. RESULTS: Growth lag in cleft side lateral lip and gradual elongation of medial lip height on the cleft side caused continuous deviation of philtrum towards the cleft side. The columellar length on the cleft side continued to grow slower, accompanied by a persistent widening of alar base width on the cleft side, leading to in the gradual deviation of columella towards the cleft side. The pre-operative and post-operative nasolabial asymmetry would increase with greater degree of postoperative deficiencies. Right clefts presented with greater degrees of deficiencies in lateral lip height in preoperative measurement, but this discrepancy of the laterality of clefts was not observed in the two follow-up periods. CONCLUSION: The surgical outcome of this modified rotational advancement technique in unilateral cleft lip primary repair is promising. Growth lag in lateral lip and lateral displacement of alar base cause continuous deviation of philtrum towards the cleft side. Pre-operative severity does predict post-operative outcomes. Laterality of oral clefts does not significantly affect the long-term outcomes of surgery. PRACTICAL IMPLICATION: This surgical technique meets the current trend of cleft lip and palate primary repair and is worth promoting.


Subject(s)
Cleft Lip , Cleft Palate , Imaging, Three-Dimensional , Photogrammetry , Humans , Cleft Lip/surgery , Cleft Lip/diagnostic imaging , Cleft Palate/surgery , Cleft Palate/diagnostic imaging , Female , Male , Photogrammetry/methods , Imaging, Three-Dimensional/methods , Infant , Treatment Outcome , Child, Preschool , Plastic Surgery Procedures/methods , Rotation , Case-Control Studies , Child
5.
Europace ; 26(10)2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39271126

ABSTRACT

AIMS: Several algorithms can differentiate inferior axis premature ventricular contractions (PVCs) originating from the right side and left side on 12-lead electrocardiograms (ECGs). However, it is unclear whether distinguishing the origin should rely solely on PVC or incorporate sinus rhythm (SR). We compared the dual-rhythm model (incorporating both SR and PVC) to the PVC model (using PVC alone) and quantified the contribution of each ECG lead in predicting the PVC origin for each cardiac rotation. METHODS AND RESULTS: This multicentre study enrolled 593 patients from 11 centres-493 from Japan and Germany, and 100 from Belgium, which were used as the external validation data set. Using a hybrid approach combining a Resnet50-based convolutional neural network and a transformer model, we developed two variants-the PVC and dual-rhythm models-to predict PVC origin. In the external validation data set, the dual-rhythm model outperformed the PVC model in accuracy (0.84 vs. 0.74, respectively; P < 0.01), precision (0.73 vs. 0.55, respectively; P < 0.01), specificity (0.87 vs. 0.68, respectively; P < 0.01), area under the receiver operating characteristic curve (0.91 vs. 0.86, respectively; P = 0.03), and F1-score (0.77 vs. 0.68, respectively; P = 0.03). The contributions to PVC origin prediction were 77.3% for PVC and 22.7% for the SR. However, in patients with counterclockwise rotation, SR had a greater contribution in predicting the origin of right-sided PVC. CONCLUSION: Our deep learning-based model, incorporating both PVC and SR morphologies, resulted in a higher prediction accuracy for PVC origin, considering SR is particularly important for predicting right-sided origin in patients with counterclockwise rotation.


Subject(s)
Deep Learning , Electrocardiography , Ventricular Premature Complexes , Humans , Ventricular Premature Complexes/diagnosis , Ventricular Premature Complexes/physiopathology , Male , Female , Middle Aged , Electrocardiography/methods , Aged , Predictive Value of Tests , Reproducibility of Results , Heart Rate , Rotation
6.
Science ; 385(6713): 1086-1090, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39236170

ABSTRACT

Cells depend on a continuous supply of adenosine triphosphate (ATP), the universal energy currency. In mitochondria, ATP is produced by a series of redox reactions, whereby an electrochemical gradient is established across the inner mitochondrial membrane. The ATP synthase harnesses the energy of the gradient to generate ATP from adenosine diphosphate (ADP) and inorganic phosphate. We determined the structure of ATP synthase within mitochondria of the unicellular flagellate Polytomella by electron cryo-tomography and subtomogram averaging at up to 4.2-angstrom resolution, revealing six rotary positions of the central stalk, subclassified into 21 substates of the F1 head. The Polytomella ATP synthase forms helical arrays with multiple adjacent rows defining the cristae ridges. The structure of ATP synthase under native operating conditions in the presence of a membrane potential represents a pivotal step toward the analysis of membrane protein complexes in situ.


Subject(s)
Chlorophyceae , Mitochondria , Mitochondrial Proton-Translocating ATPases , Adenosine Diphosphate/metabolism , Adenosine Triphosphate/metabolism , Cryoelectron Microscopy , Electron Microscope Tomography , Mitochondria/enzymology , Mitochondria/ultrastructure , Mitochondrial Membranes/enzymology , Mitochondrial Membranes/metabolism , Mitochondrial Proton-Translocating ATPases/chemistry , Mitochondrial Proton-Translocating ATPases/metabolism , Rotation , Chlorophyceae/enzymology
7.
Am J Sports Med ; 52(11): 2893-2901, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39222084

ABSTRACT

BACKGROUND: Individual maximum joint and segment angular velocities have shown positive associations with throwing arm kinetics and ball velocity in baseball pitchers. PURPOSE: To observe how cumulative maximum joint and segment angular velocities, irrespective of sequence, affect ball velocity and throwing arm kinetics in high school pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: High school (n = 55) pitchers threw 8 to 12 fastball pitches while being evaluated with 3-dimensional motion capture (480 Hz). Maximum joint and segment angular velocities (lead knee extension, pelvis rotation, trunk rotation, shoulder internal rotation, and forearm pronation) were calculated for each pitcher. Pitchers were classified as overall fast, overall slow, or high velocity for each joint or segment velocity subcategory, or as population, with any pitcher eligible to be included in multiple subcategories. Kinematic and kinetic parameters were compared among the various subgroups using t tests with post hoc regressions and multivariable regression models created to predict throwing arm kinetics and ball velocity, respectively. RESULTS: The lead knee extension and pelvis rotation velocity subgroups achieved significantly higher normalized elbow varus torque (P = .016) and elbow flexion torque (P = .018) compared with population, with equivalent ball velocity (P = .118). For every 1-SD increase in maximum pelvis rotation velocity (87 deg/s), the normalized elbow distractive force increased by 4.7% body weight (BW) (B = 0.054; ß = 0.290; P = .013). The overall fast group was older (mean ± standard deviation, 16.9 ± 1.4 vs 15.4 ± 0.9 years; P = .007), had 8.9-mph faster ball velocity (32.7 ± 3.1 vs 28.7 ± 2.3 m/s; P = .002), and had significantly higher shoulder internal rotation torque (63.1 ± 17.4 vs 43.6 ± 12.0 Nm; P = .005), elbow varus torque (61.8 ± 16.4 vs 41.6 ± 11.4 Nm; P = .002), and elbow flexion torque (46.4 ± 12.0 vs 29.5 ± 6.8 Nm; P < .001) compared with the overall slow group. A multiregression model for ball velocity based on maximum joint and segment angular velocities and anthropometrics predicted 53.0% of variance. CONCLUSION: High school pitchers with higher maximum joint and segment velocities, irrespective of sequence, demonstrated older age and faster ball velocity at the cost of increased throwing shoulder and elbow kinetics. CLINICAL RELEVANCE: Pitchers and coaching staff should consider this trade-off between faster ball velocity and increasing throwing arm kinetics, an established risk factor for elbow injury.


Subject(s)
Baseball , Humans , Baseball/physiology , Biomechanical Phenomena , Adolescent , Male , Rotation , Arm/physiology , Torque , Forearm/physiology , Pelvis/physiology , Elbow Joint/physiology , Shoulder/physiology , Range of Motion, Articular/physiology , Elbow/physiology , Kinetics
8.
Sci Rep ; 14(1): 20417, 2024 09 03.
Article in English | MEDLINE | ID: mdl-39223229

ABSTRACT

Currently, the relationship between axial rotation of the vertebrae and bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) remains controversial. The aim of this study is to quantitatively assess the effect of vertebral rotation on volumetric bone mineral density (v-BMD) and areal bone mineral density (a-BMD), further to propose the corrected strategies. To achieve this, a phantom, which was rotated from 0° to 25° in 5° increments, was utilized. Bone mineral content (BMC), a-BMD, v-BMD, and projected area (p-AREA) were measured. The Kruskal-Wallis non-parametric test or one-way ANOVA was used to examine the differences in variables between the different groups. The Pearson and Spearman correlation was used to test the relationships between quantitative parameters and rotated angles. Linear regression analysis was used to evaluate the relationship between angles and quantitative parameters. The findings indicate that, as the angle increased, a-BMD and v-BMD decreased (P < 0.001) , and the p-AREA increased (P < 0.001), but the BMC stays constant. The rotated angle was negative correlated (r = - 0.925, P < 0.001) with a-BMD and v-BMD (r = - 0.880, P < 0.001), positive (r = 0.930, P = < 0.001) correlated with p-AREA. The linear regression analysis showed that a-BMD = 0.808-0.01 × Angle and v-BMD = 151.808-1.588 × Angle. This study showed that, axial rotation might lead to a lower measured for a-BMD and v-BMD, it should be modified. This gives clinicians some insights into how to deal with osteoporosis in scoliosis patients. It's essential for clinicians to incorporate these findings into their diagnostic processes to prevent potential misdiagnosis and over-treatment of osteoporosis.


Subject(s)
Absorptiometry, Photon , Bone Density , Lumbar Vertebrae , Tomography, X-Ray Computed , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/physiology , Tomography, X-Ray Computed/methods , Rotation , Phantoms, Imaging
9.
PLoS One ; 19(9): e0308035, 2024.
Article in English | MEDLINE | ID: mdl-39236040

ABSTRACT

BACKGROUND: Cardiac rotational parameters in primary symptomatic left ventricular noncompaction (LVNC) with preserved left ventricular ejection fraction (LVEF) are not well understood. We aimed to analyze cardiac rotation measured with cardiac magnetic resonance feature-tracking (CMR-FT) and speckle-tracking echocardiography (Echo-ST) in LVNC morphology subjects with preserved LVEF and different genotypes and healthy controls. METHODS: Our retrospective study included 54 LVNC subjects with preserved LVEF and 54 control individuals. We evaluated functional and rotational parameters with CMR in the total study population and with echocardiography in 39 LVNC and 40 C individuals. All LVNC subjects were genotyped with a 174-gene next-generation sequencing panel and grouped into the subgroups: benign (B), variant of uncertain significance (VUS), and pathogenic (P). RESULTS: In comparison with controls, LVNC subjects had reduced apical rotational degree (p = 0.004) and one-third had negative apical rotation. While the degree of apical rotation was comparable between the three genetic subgroups, they differed significantly in the direction of apical rotation (p<0.001). In contrast to control and B groups, all four studied cardiac rotational patterns were identified in the P and VUS subgroups, namely normal rotation, positive and negative rigid body rotation, and reverse rotation. When the CMR-FT and Echo-ST methods were compared, the direction and pattern of cardiac rotation had moderate to good association (p<0.001) whereas the rotational degrees showed no reasonable correlation or agreement. CONCLUSION: While measuring cardiac rotation using both CMR-FT and Echo-ST methods, subclinical mechanical differences were identified in subjects with LVNC phenotype and preserved LVEF, especially in cases with genetic involvement.


Subject(s)
Echocardiography , Multimodal Imaging , Humans , Male , Female , Middle Aged , Echocardiography/methods , Retrospective Studies , Rotation , Multimodal Imaging/methods , Adult , Stroke Volume , Ventricular Function, Left/physiology , Magnetic Resonance Imaging/methods , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathology , Aged , Case-Control Studies , Isolated Noncompaction of the Ventricular Myocardium/diagnostic imaging , Isolated Noncompaction of the Ventricular Myocardium/genetics , Isolated Noncompaction of the Ventricular Myocardium/physiopathology
10.
Acta Bioeng Biomech ; 26(1): 165-178, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-39219085

ABSTRACT

Purpose: Previous studies have proven that modifications in the natural walking technique alter muscle activation and energy consumption. This research aimed to determine the differences in muscle activation, energy consumption, kinematic characteristics, perceived muscular exertion and perceived cardio-respiratory fatigue between natural and modified walking techniques with altered pelvic height and rotation. Methods: Nine physically active, non-injured males walked on a treadmill. Modified walking techniques assumed maintenance of constant pelvic height and application of maximal pelvic rotation. Walking speed was subtransit - 0.4 km/h less than the transit. Sampled variables were: average normalized maximal activation during contact and swing phase relativized to maximal voluntary activation, average submaximal oxygen consumption relativized to body mass and subtransit speed, average step length and frequency, rating of perceived muscular exertion and perceived cardio-respiratory fatigue. Muscle activation, energy consumption and kinematic characteristics were assessed throughout each walking session. Perceived muscular exertion and perceived cardio-respiratory fatigue were evaluated post-session. Electromyographic activity was assessed for rectus femoris, gluteus maximus, vastus medialis, biceps femoris, tibialis anterior and gastrocnemius lateralis. Results: The most significant changes in muscle activation were observed during the contact phase. A decrease in pelvic height increased muscle activation of rectus femoris, vastus medialis and gastrocnemius lateralis. An increase in pelvic rotation increased muscle activation of all monitored muscles except for gluteus maximus. Both modifications increased energy consumption, perceived muscular exertion and perceived cardio-respiratory fatigue, and altered kinematic characteristics. Conclusions: Modifications in pelvic height and rotation at the same walking speed alter muscle activation, energy consumption, kinematic characteristics, perceived exertion and fatigue.


Subject(s)
Energy Metabolism , Muscle, Skeletal , Pelvis , Walking , Humans , Male , Pelvis/physiology , Walking/physiology , Energy Metabolism/physiology , Rotation , Muscle, Skeletal/physiology , Biomechanical Phenomena , Young Adult , Adult , Electromyography , Oxygen Consumption/physiology , Muscle Contraction/physiology
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