Structural diversity of tick-borne encephalitis virus particles in the inactivated vaccine based on strain Sofjin

The main approach to preventing tick-borne encephalitis (TBE) is vaccination. Formaldehyde-inactivated TBE vaccines have a proven record of safety and efficiency but have never been characterized structurally with atomic resolution. We report a cryoelectron microscopy (cryo-EM) structure of the formaldehyde-inactivated TBE virus (TBEV) of Sofjin-Chumakov strain representing the Far-Eastern subtype. A 3.8 Å resolution reconstruction reveals the structural integrity of the envelope E proteins, specifically the E protein ectodomains. The comparative study shows a high structural similarity to the previously published structures of the TBEV European subtype strains Hypr and Kuutsalo-14. A fraction of inactivated virions exhibits asymmetric features including the deformations of the membrane profile. We propose that the heterogeneity is caused by inactivation and perform a local variability analysis on the small parts of the envelope protein shell to reveal membrane curvature features possibly induced by the inactivation. The results of this study will have implications for the design of novel vaccines against diseases caused by flaviviruses.

Effects of a Passive Back-Support Exosuit on Erector Spinae and Abdominal Muscle Activity During Short-Duration, Asymmetric Trunk Posture Maintenance Tasks

OBJECTIVE

To examine the effects of asymmetry and lower extremity mobility restrictions on the effectiveness of a passive back-support exosuit in short-duration, static trunk flexion postures.

BACKGROUND

The effectiveness of trunk exoskeletons/suits for sagittally symmetric trunk posture maintenance has been investigated, but there has been limited study of the effects of asymmetric trunk postures or lower extremity motion restriction.

METHOD

Sixteen participants held trunk flexion postures involving trunk flexion (20°, 40°, 60°), asymmetry (0°, 30°), and lower extremity mobility (Free, Restricted) for 3 s. Participants held these postures with and without an exosuit while erector spinae and abdominal muscle activities were collected.

RESULTS

There were no significant interactions between exosuit and asymmetry or exosuit and lower extremity motion restrictions, indicating no significant effects of these factors on the effectiveness of the exosuit at reducing trunk muscle activity. The exosuit was found to be effective at reducing erector spinae muscle activity regardless of asymmetry of posture or lower extremity restrictions (average 21%, from 11.2% MVC to 8.8% MVC). The magnitude of the erector spinae activity at 60° of trunk flexion with the exosuit was similar to that seen at 20° without the exosuit.

CONCLUSION

The exosuit consistently provided biomechanical benefit through reduced activation of the erector spinae muscles and neither asymmetry of trunk posture nor lower extremity restriction influenced this effectiveness.

APPLICATION

Trunk exoskeletons/suits can reduce trunk muscle activation and understanding how characteristics of the trunk postures assumed impact these responses may help target tasks wherein these devices may be effective.

Older persons' experiences of care encounters in their home: A multiple-case study

AIM

To explore and describe older persons' unique experiences of care encounters with home care nurses in a real-life context.

BACKGROUND

The increasing number of older persons in society contributes to increases in age-related impairments compromising their quality of life. Future care consists of "hospitals at home" where care encounters occur in a person's private domain, partly becoming a clinical workplace. Scant research has focused on how older persons experience care encounters with home care nurses and needs to be highlighted.

DESIGN

Multiple-case study.

METHODS

The cases relied on replication logic and five purposive sampled older persons were interviewed. Data were analysed using qualitative content analysis and differences within and between cases were explored and findings across the cases were replicated.

FINDINGS

The cross-analysis emerged in three categories: "Nursing routine rules the care encounters", "Lack of knowledge and information" and "Dependency on support from others".

CONCLUSIONS

Our research has found that older persons face challenges while receiving home care, including limited engagement in their care and the need for enhanced support. Implementing person-centred care in homes poses ethical challenges that require careful consideration. Home care nurses should prioritise understanding each patient individually, recognising them beyond their patient role, which necessitates more thorough and time-sensitive care encounters.

REPORTING METHOD

Findings were reported using COREQ guidelines.

PATIENT OR PUBLIC CONTRIBUTION

Patients were interviewed and contributed with data for this study.

IMPLICATIONS FOR THE PROFESSION AND PATIENT CARE

This study emphasises the need to prioritise individualised care in home settings and listen to the voices of older individuals to enhance quality.

An Indian classical dance form, Kathak in maintaining handgrip strength symmetry and reducing the risk of hypertension

BACKGROUND

The present paper aimed to study handgrip strength (HGS) asymmetry and its association with hypertension in a sample of Kathak dancers and non-dancers of North India.

METHODS

Data on HGS and blood pressure were collected from 206 Kathak dancers and 235 age-matched controls, using standardized protocols. Pearson correlation coefficients assessed the association between HGS and hypertension, and binary logistic regression identified the risk of developing hypertension.

RESULTS

HGS asymmetry was higher among non-dancers. In Kathak dancers, systolic blood pressure (SBP) was positively correlated with HGS and negatively correlated with HGS asymmetry whereas diastolic blood pressure (DBP) was negatively correlated with both HGS and HGS asymmetry. Dancers with high HGS, have significantly reduced risk of developing hypertension. Non-dancers with HGS asymmetry were 1.8 times more likely to report hypertension, relative to dancers.

CONCLUSION

Kathak may be used as an alternative method for maintaining HGS symmetry and reducing the risk of developing hypertension.

Adaptation strategies of the Icelandic horse with induced forelimb lameness at walk, trot and tölt

BACKGROUND AND OBJECTIVE

Lameness assessment in the gaited Icelandic horse is complex. We aimed to describe their kinematic and temporal adaptation strategies in response to forelimb lameness at walk, trot and tölt.

STUDY DESIGN

In vivo experiment.

METHODS

Ten clinically non-lame Icelandic horses were measured before and after reversible forelimb lameness induction. Upper body and limb kinematics were measured using 11 inertial measurement units mounted on the poll, withers, pelvis (tubera sacrale) and all four limbs and hoofs (Equimoves®, 500 Hz). Horses were measured on a straight line at walk and trot in-hand and at walk, trot and tölt while ridden. Linear mixed models were used to compare baseline and lame conditions (random factor = 'horse'), and results are presented as the difference in estimated marginal means or percentage of change.

RESULTS

Lameness induction significantly (p < 0.05) increased head vertical movement asymmetry at walk (HDmin/HDmaxHAND: 18.8/5.7 mm, HDmin/HDmaxRIDDEN: 9.8/0.3 mm) and trot (HDmin/HDmaxHAND: 18.1/7.8 mm, HDmin/HDmaxRIDDEN: 24.0/9.3 mm). At the tölt, however, HDmin did not change significantly (1.1 mm), but HDmax increased by 11.2 mm (p < 0.05). Furthermore, pelvis vertical movement asymmetry (PDmax) increased by 4.9 mm, sound side dissociation decreased (-8.3%), and sound diagonal dissociation increased (6.5%). Other temporal stride variables were also affected, such as increased stance duration of both forelimbs at walk, tölt and in-hand trot.

MAIN LIMITATIONS

Only one degree of lameness (mild) was induced with an acute lameness model.

CONCLUSIONS

Classical forelimb lameness metrics, such as vertical head and withers movement asymmetry, were less valuable at tölt compared to walk and trot, except for HDmax. Therefore, it is advised to primarily use the walk and trot to detect and quantify forelimb lameness in the Icelandic horse.

The coronavirus disease 2019 infodemic: a concept analysis

Aim

This study aimed to analyze the coronavirus disease 2019 (COVID-19) infodemic phenomenon in the medical field, providing essential data to help healthcare professionals understand it.

Methods

This study utilized a hybrid model for concept analysis. In the theoretical phase (first phase), a literature review was conducted using ScienceDirect, PubMed, CINAHL, ProQuest, Scopus, Web of Science, DBpia, RISS, and KISS. Semi-structured interviews, involving eight physicians and six nurses, were used in the fieldwork phase (second phase). In the final analysis phase (third phase), the results of the preceding phases were combined.

Results

Based on the findings of these phases, the COVID-19 infodemic can be defined as "the phenomenon of information flood, reproduction, dissemination, and asymmetry, which occurred during the pandemic through social networks among the public lacking essential knowledge of infectious disease, and is associated with negative and positive effects."

Conclusion

Our findings can help the Ministry of Health and Welfare and healthcare professionals to understand the phenomenon of the infodemic and prepare necessary strategies and education programs for the public. Therefore, the provision of basic data is important for developing influential roles for healthcare professionals during infectious disease outbreaks.

The Asymmetry Observed between the Effects of Photon-Phonon Coupling and Crystal Field on the Fine Structure of Fluorescence and Spontaneous Four-Wave Mixing in Ion-Doped Microcrystals

In this paper, we explore the asymmetry observed between the effects of photon-phonon coupling (nested-dressing) and a crystal field (CF) on the fine structure of fluorescence (FL) and spontaneous four-wave mixing (SFWM) in Eu3+: BiPO4 and Eu3+: NaYF4. The competition between the CF and the strong photon-phonon dressing leads to dynamic splitting in two directions. The CF leads to static splitting in one direction under weak phonon dressing. The evolution from strong dressing to weak dressing results in spectral asymmetry. This spectral asymmetry includes out-of-phase FL and in-phase SFWM. Further, the large ratio between the dressing Rabi frequency and the de-phase rate leads to strong FL and SFWM asymmetry due to photon-phonon constructive dressing. Moreover, the experimental results suggest the analogy of a spectra asymmetry router with a channel equalization ratio of 96.6%.

Coalescence-Induced Self-Propelled Particle Transport with Asymmetry Arrangement

We experimentally investigated the coalescence-induced droplet-particle jumping phenomenon on a submillimeter scale in symmetric and asymmetric particle arrangements with poly(methyl methacrylate) (PMMA) particles and stainless steel (SS) particles. Coalescence-induced droplet-particle jumping exhibited excellent capability and interesting behavior for both droplet jumping enhancement and particle transport. The particle increased the normalized droplet jumping velocity from 0.250 for no particle case to 0.315 and 0.320 for symmetric and asymmetric particle cases. Compared with similar-sized macrostructures fixed between droplets, better jumping performance with particles may be attributed to avoiding the work of adhesion during droplet-macrostructure separation. Besides, all particles always sunk at the bottom in the symmetric cases, while the stick mode for PMMA particles and sink, wander, and jet modes for SS particles appeared in the asymmetry cases. We revealed that the asymmetric particle arrangement induces an unbalanced surface tension force, which may provide a driving force in the vertical direction. Additionally, a small enough resistive force caused by hydrophobic particles is another necessary condition for the wonder and jet mode. Finally, we realized a significantly superior particle transport in the asymmetric SS particle cases with maximum particle height reaching ∼2.1 mm, ∼12.4 times the particle radius, the most significant vertical self-propelled transport distance currently.

EncoMPASS: An encyclopedia of membrane proteins analyzed by structure and symmetry

Protein structure determination and prediction, active site detection, and protein sequence alignment techniques all exploit information about protein structure and structural relationships. For membrane proteins, however, there is limited agreement among available online tools for highlighting and mapping such structural similarities. Moreover, no available resource provides a systematic overview of quaternary and internal symmetries, and their orientation relative to the membrane, despite the fact that these properties can provide key insights into membrane protein function and evolution. Here, we describe the Encyclopedia of Membrane Proteins Analyzed by Structure and Symmetry (EncoMPASS), a database for relating integral membrane proteins of known structure from the points of view of sequence, structure, and symmetry. EncoMPASS is accessible through a web interface, and its contents can be easily downloaded. This allows the user not only to focus on specific proteins, but also to study general properties of the structure and evolution of membrane proteins.

Asymmetry in Class II subdivision malocclusion: Assessment based on 3D surface models

INTRODUCTION

There is currently no consensus in the literature whether the aetiology of a Class II subdivision is dental, skeletal or both. The aim of this study was to identify and quantify skeletal and dental asymmetries in Class II subdivision malocclusions.

METHODS

CBCTs from 33 Class II subdivision malocclusion patients were used to construct 3D volumetric label maps. Eighteen landmarks were identified. The original scan and associated 3D volumetric label map were mirrored. Registration of the original and mirrored images relative to the anterior cranial base, maxilla and mandible were performed. Surface models were generated, and 3D differences were quantified. Statistical analysis was performed.

RESULTS

Anterior cranial base registration showed significant differences for fossa vertical difference, fossa roll, mandibular yaw, mandibular lateral displacement and lower midline displacement. Regional registrations showed significant differences for antero-posterior (A-P) mandibular length, maxillary roll, A-P maxillary first molar position, maxillary first molar yaw and maxillary first molar roll. Class II subdivision patients also show an asymmetric mandibular length as well as an asymmetric gonial angle. Moderate correlations were found between the A-P molar relationship and fossa A-P difference, mandibular first molar A-P difference, maxillary first molar A-P difference and maxillary first molar yaw.

CONCLUSIONS

This study suggests that Class II subdivisions can result from both significant skeletal and dental factors. Skeletal factors include a shorter mandible as well as posterior and higher displacement of the fossa on the Class II side, resulting in mandibular yaw. Dental factors include maxillary and mandibular first molar antero-posterior asymmetry.

Mechanism of GTPase activation of a prokaryotic small Ras-like GTPase MglA by an asymmetrically interacting MglB dimer

Cell polarity oscillations in Myxococcus xanthus motility are driven by a prokaryotic small Ras-like GTPase, mutual gliding protein A (MglA), which switches from one cell pole to the other in response to extracellular signals. MglA dynamics is regulated by MglB, which functions both as a GTPase activating protein (GAP) and a guanine nucleotide exchange factor (GEF) for MglA. With an aim to dissect the asymmetric role of the two MglB protomers in the dual GAP and GEF activities, we generated a functional MglAB complex by coexpressing MglB with a linked construct of MglA and MglB. This strategy enabled us to generate mutations of individual MglB protomers (MglB1 or MglB2 linked to MglA) and delineate their role in GEF and GAP activities. We establish that the C-terminal helix of MglB1, but not MglB2, stimulates nucleotide exchange through a site away from the nucleotide-binding pocket, confirming an allosteric mechanism. Interaction between the N-terminal β-strand of MglB1 and β0 of MglA is essential for the optimal GEF activity of MglB. Specific residues of MglB2, which interact with Switch-I of MglA, partially contribute to its GAP activity. Thus, the role of the MglB2 protomer in the GAP activity of MglB is limited to restricting the conformation of MglA active site loops. The direct demonstration of the allosteric mechanism of GEF action provides us new insights into the regulation of small Ras-like GTPases, a feature potentially present in many uncharacterized GEFs.

Thickness Asymmetry of the Vertebral Artery Groove: A Dried Vertebrae Study

BACKGROUND

The vertebral artery groove (VAG), located on the posterior arch of the first cervical (atlas) vertebra plays a pivotal role in guiding the vertebral artery's (VA) third part (V3). Deviations in VAG morphology and morphometry (dimensions) can influence vascular dynamics and pose clinical implications.

AIM

The current study delves into the morphometric variants and explores the less-explored morphometric variable of the VAG thickness, highlighting possible laterality (asymmetry).

METHODS

A morphometric investigation was conducted on 141 dried atlas (73 male and 68 female) vertebrae from a Greek adult population. The VAG's minimum thickness was investigated by considering the laterality (sides' differences), gender, and age impact on it. Measurements were performed by two independent researchers, ensuring the data reliability.

RESULTS

A significant asymmetry was identified in the VAG thickness between the left (3.9 ± 0.9 mm) and right (4.1 ± 1.1 mm) (p=0.005) sides, with the left side having the mean minimum thickness. Gender had a significant impact on VAG thickness only on the left side, with females presenting a significantly thinner left-sided VAG (3.6 ± 0.9 mm) than males (4.10 ± 0.7 mm) (p=0.001). Age had no significant impact on the VAG thickness.  Conclusion: The present study underscores the significance of asymmetry in the VAG thickness in craniocervical interventions. This less-explored morphometric variable warrants careful consideration by surgeons during preoperative planning to minimize potential complications. The current findings highlight the importance of understanding the VAG thickness asymmetry and its clinical implications, as this osseous variable may be an index of a different diameter of the VA by side. It is recommended that surgeons incorporate this variable into their preoperative assessments to improve the safety and efficacy of craniocervical interventions.

Assessment of Lateral Abdominal Muscle Activation Asymmetry via M-mode Ultrasonography

INTRODUCTION

This study aimed to evaluate the asymmetry in the lateral abdominal muscles (LAMs) expressed as tissue deformation index asymmetry (aTDI) with the use of M-mode ultrasonography. The muscles of interest were the transversus abdominis, internal oblique, and external oblique.

METHODS

This is a cohort of 126 healthy subjects who participated in the study. Measurements were taken by two raters, blinded to the aim of the study. M-mode ultrasounds with a measurement frequency of 5 MHz were utilized to record the postural response of LAMs to external perturbation in the form of rapid arm abduction with load, and individual aTDI values for each muscle were calculated.

RESULTS

The aTDI values from deep to superficial LAMs were 78.28% for transversus abdominis, 55.68% for internal oblique, and 44.80% for external oblique. Only the aTDI for transversus abdominis results differed significantly from those of the other LAMs (P<0.05).

CONCLUSION

LAM asymmetry values exhibit the following gradient: transversus abdominis >internal oblique >external oblique. Specifically, only transversus abdominis demonstrates noteworthy asymmetry in postural activity. This observation contributes to the literature by indicating that transversus abdominis asymmetry may serve as a marker for assessing the variability in motor control of the deep abdominal musculature. The dominance of transversus abdominis (TrA) asymmetric activity underlines the importance of personalized approaches for patients with lumbopelvic disorders or for athletes seeking to enhance performance.

LFK index does not reliably detect small-study effects in meta-analysis: A simulation study

The LFK index has been promoted as an improved method to detect bias in meta-analysis. Putatively, its performance does not depend on the number of studies in the meta-analysis. We conducted a simulation study, comparing the LFK index test to three standard tests for funnel plot asymmetry in settings with smaller or larger group sample sizes. In general, false positive rates of the LFK index test markedly depended on the number and size of studies as well as the between-study heterogeneity with values between 0% and almost 30%. Egger's test adhered well to the pre-specified significance level of 5% under homogeneity, but was too liberal (smaller groups) or conservative (larger groups) under heterogeneity. The rank test was too conservative for most simulation scenarios. The Thompson-Sharp test was too conservative under homogeneity, but adhered well to the significance level in case of heterogeneity. The true positive rate of the LFK index test was only larger compared with classic tests if the false positive rate was inflated. The power of classic tests was similar or larger than the LFK index test if the false positive rate of the LFK index test was used as significance level for the classic tests. Under ideal conditions, the false positive rate of the LFK index test markedly and unpredictably depends on the number and sample size of studies as well as the extent of between-study heterogeneity. The LFK index test in its current implementation should not be used to assess funnel plot asymmetry in meta-analysis.

The Impact of Interaction between Body Posture and Movement Pattern Quality on Injuries in Amateur Athletes

Background: this study aimed to examine the impact of interaction between body posture and the quality of movement patterns on injury frequencies in amateur athletes. Methods: The study sample consisted of 89 young amateur athletes. Movement pattern quality was assessed by the Functional Movement Screen (FMS), test and body posture in the frontal plane was assessed by the moire method for the parameters Shoulder Slope Angle, Lower Scapula Protrusion Difference, and Pelvic Tilt Angle. Injury data were collected through completion of the Injury History Questionnaire for the past 12 months. Results: Using cluster analysis, participants were allocated into a either category with good (BPg) body posture or poor (BPp), and using FMS cutoff points (14), either a category of good movement pattern quality (MPg) or poor (MPp). Two-way ANOVA was performed, and the Bonferroni post-hoc test revealed a reduction in injuries among participants from the MPg-BPg group compared to the other three groups (p < 0.05). However, no interaction between factors was revealed. No statistically significant differences were observed among the remaining three groups in the case of injury prevalence (p > 0.05). Conclusions: A combination of proper body posture and high-quality movement patterns is associated with a lower frequency of injuries, without direct interaction between chosen factors, which suggests that they impact injury risk independently. Practicing suitable BP and ensuring high-quality MPs should be regarded as a strategy in injury prevention.

Stepwise introduction of stabilizing mutations reveals nonlinear additive effects in de novo TIM barrels

Over the past decades, the TIM-barrel fold has served as a model system for the exploration of how changes in protein sequences affect their structural, stability, and functional characteristics, and moreover, how this information can be leveraged to design proteins from the ground up. After numerous attempts to design de novo proteins with this specific fold, sTIM11 was the first validated de novo design of an idealized four-fold symmetric TIM barrel. Subsequent efforts to enhance the stability of this initial design resulted in the development of DeNovoTIMs, a family of de novo TIM barrels with various stabilizing mutations. In this study, we present an investigation into the biophysical and thermodynamic effects upon introducing a varying number of stabilizing mutations per quarter along the sequence of a four-fold symmetric TIM barrel. We compared the base design DeNovoTIM0 without any stabilizing mutations with variants containing mutations in one, two, three, and all four quarters-designated TIM1q, TIM2q, TIM3q, and DeNovoTIM6, respectively. This analysis revealed a stepwise and nonlinear change in the thermodynamic properties that correlated with the number of mutated quarters, suggesting positive nonadditive effects. To shed light on the significance of the location of stabilized quarters, we engineered two variants of TIM2q which contain the same number of mutations but positioned in different quarter locations. Characterization of these TIM2q variants revealed that the mutations exhibit varying effects on the overall protein stability, contingent upon the specific region in which they are introduced. These findings emphasize that the amount and location of stabilized interfaces among the four quarters play a crucial role in shaping the conformational stability of these four-fold symmetric TIM barrels. Analysis of de novo proteins, as described in this study, enhances our understanding of how sequence variations can finely modulate stability in both naturally occurring and computationally designed proteins.

The effective connectivity analysis of fMRI based on asymmetric detection of transfer brain entropy

It is important to explore causal relationships in functional magnetic resonance imaging study. However, the traditional effective connectivity analysis method is easy to produce false causality, and the detection accuracy needs to be improved. In this paper, we introduce a novel functional magnetic resonance imaging effective connectivity method based on the asymmetry detection of transfer entropy, which quantifies the disparity in predictive information between forward and backward time, subsequently normalizing this disparity to establish a more precise criterion for detecting causal relationships while concurrently reducing computational complexity. Then, we evaluate the effectiveness of this method on the simulated data with different level of nonlinearity, and the results demonstrated that the proposed method outperforms others methods on the detection of both linear and nonlinear causal relationships, including Granger Causality, Partial Granger Causality, Kernel Granger Causality, Copula Granger Causality, and traditional transfer entropy. Furthermore, we applied it to study the effective connectivity of brain functional activities in seafarers. The results showed that there are significantly different causal relationships between different brain regions in seafarers compared with non-seafarers, such as Temporal lobe related to sound and auditory information processing, Hippocampus related to spatial navigation, Precuneus related to emotion processing as well as Supp_Motor_Area associated with motor control and coordination, which reflects the occupational specificity of brain function of seafarers.

Cognitively defined Alzheimer's dementia subgroups have distinct atrophy patterns

INTRODUCTION

We sought to determine structural magnetic resonance imaging (MRI) characteristics across subgroups defined based on relative cognitive domain impairments using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) and to compare cognitively defined to imaging-defined subgroups.

METHODS

We used data from 584 people with Alzheimer's disease (AD) (461 amyloid positive, 123 unknown amyloid status) and 118 amyloid-negative controls. We used voxel-based morphometry to compare gray matter volume (GMV) for each group compared to controls and to AD-Memory.

RESULTS

There was pronounced bilateral lower medial temporal lobe atrophy with relative cortical sparing for AD-Memory, lower left hemisphere GMV for AD-Language, anterior lower GMV for AD-Executive, and posterior lower GMV for AD-Visuospatial. Formal asymmetry comparisons showed substantially more asymmetry in the AD-Language group than any other group (p = 1.15 × 10-10 ). For overlap between imaging-defined and cognitively defined subgroups, AD-Memory matched up with an imaging-defined limbic predominant group.

DISCUSSION

MRI findings differ across cognitively defined AD subgroups.

Mirror, mirror? An evaluation of identical twin mirroring in tooth crown morphology

It has been estimated that 25% of monozygotic ("identical") twin pairs exhibit reverse asymmetry (RA) or "mirroring" of minor anatomical features as a result of delayed zygote division. Here, we examine whether identical twin mirroring accounts for patterns of dental asymmetry in a sample of monozygotic and dizygotic ("fraternal") twins. We focus on crown morphology to approach the following question: is there an association between dental RA frequency and twin type suggestive of the presence of mirror image twins in our sample? Data were collected from 208 deciduous and 196 permanent dentitions of participants of the University of Adelaide Twin Study using Arizona State University Dental Anthropology System standards. RA frequencies were compared across morphological complexes (deciduous, permanent), twin types (monozygotic, dizygotic), and traits. Fisher's exact tests were performed to formally evaluate the association between twin type and dental RA. Across the entire dataset, RA rates failed to exceed 8% for any twin type. In monozygotic twins, deciduous mirroring totaled 5.3% of observed cases, while permanent mirroring totaled 7.8% of observed cases. We found no statistically significant association between RA and twin type for any morphological character (p-value range: 0.07-1.00). Our results suggest the timing of monozygotic twin division does not explain the structure of asymmetry for our morphology dataset and that published estimates of identical twin mirroring rates may be inflated or contingent upon phenotype. Instead, rates reported for this sample more closely align with the proposed etiology of this condition.

Asymmetries in Infants' Vowel Perception: Changes in Vowel Discrimination in German Learning 6- and 9-Month-Old Infants

Infants' speech perception is characterized by substantial changes during the first year of life that attune the processing mechanisms to the specific properties of the ambient language. This paper focuses on these developmental changes in vowel perception. More specifically, the emergence and potential cause of perceptual asymmetries in vowel perception are investigated by an experimental study on German 6- and 9-month-olds' discrimination of a vowel contrast that is not phonemic in German. Results show discrimination without any asymmetry in the 6-month-olds but an asymmetrical pattern with better performance when the vowel changes from the less focal to the more focal vowel than vice versa by the 9-month-olds. The results concerning the asymmetries are compatible with the Natural Referent Framework as well as with the Native Language Magnet model. Our results foster two main conclusions. First, bi-directional testing must be mandatory when testing vowel perception. Second, when testing non-native vowel perception, the relation of the stimuli to the native language vowel system has to be considered very carefully as this system impacts the perception of non-native vowels.

EEG-based major depressive disorder recognition by neural oscillation and asymmetry

Background

Major Depressive Disorder (MDD) is a pervasive mental health issue with significant diagnostic challenges. Electroencephalography (EEG) offers a non-invasive window into the neural dynamics associated with MDD, yet the diagnostic efficacy is contingent upon the appropriate selection of EEG features and brain regions.

Methods

In this study, resting-state EEG signals from both eyes-closed and eyes-open conditions were analyzed. We examined band power across various brain regions, assessed the asymmetry of band power between the hemispheres, and integrated these features with clinical characteristics of MDD into a diagnostic regression model.

Results

Regression analysis found significant predictors of MDD to be beta2 (16-24 Hz) power in the Prefrontal Cortex (PFC) with eyes open (B = 20.092, p = 0.011), beta3 (24-40 Hz) power in the Medial Occipital Cortex (MOC) (B = -12.050, p < 0.001), and beta2 power in the Right Medial Frontal Cortex (RMFC) with eyes closed (B = 24.227, p < 0.001). Asymmetries in beta1 (12-16 Hz) power with eyes open (B = 28.047, p = 0.018), and in alpha (8-12 Hz, B = 9.004, p = 0.013) and theta (4-8 Hz, B = -13.582, p = 0.008) with eyes closed were also significant predictors.

Conclusion

The study confirms the potential of multi-region EEG analysis in improving the diagnostic precision for MDD. By including both neurophysiological and clinical data, we present a more robust approach to understanding and identifying this complex disorder.

Limitations

The research is limited by the sample size and the inherent variability in EEG signal interpretation. Future studies with larger cohorts and advanced analytical techniques are warranted to validate and refine these findings.

Bilateral differences of isokinetic knee extensor strength are velocity- and task-dependent

The purpose of this study was to investigate the concordance of isokinetic bilateral strength differences of the knee extensors in single- and multi-joint movement tasks. One hundred and nineteen male athletes performed isokinetic legpresses at 0.1 m/s and 0.7 m/s as well as isokinetic knee extensions at 60°/s and 180°/s. Bilateral differences and directed bilateral differences (sign indicating the direction of the difference) were calculated for all measurements. Bland-Altman-Plots were plotted to investigate if the different conditions detect bilateral differences of the same magnitude. Additionally, concordance correlations for the directed bilateral differences of the different tests were calculated to investigate magnitude and direction. The results indicate poor to fair concordance between the bilateral differences in the legpress conditions as well as between single- and multi-joint tasks. The single-joint knee extensions displayed a moderate level of agreement. Bilateral strength differences in isokinetic movement tasks are dependent on movement velocity and the nature of the task (single- or multi-joint movement) in the lower extremities. Both the value and the direction of the strength differences show no clear pattern across the investigated measurements and cannot be used interchangeably. Therefore, to assess interlimb strength balance, multiple different tests should be performed.

A five-day-old child with lipid hemihypertrophy: A case report

Key Clinical Message

Lipid hemihypertrophy should be considered in the differential diagnosis of neonatal asymmetry. Early recognition and further evaluation for associated disorders are important for appropriate management and surveillance of potential complications.

Abstract

We present the case of a 5-day-old female neonate who presented with a visibly enlarged right thigh, right labia majora, and below the right mandible. This case report highlights the importance of early identification, comprehensive evaluation, and multidisciplinary management in neonates with lipid hemihypertrophy to optimize their long-term outcomes and quality of life.

Bilateral brain microstructural alterations in patients with left-sided classic trigeminal neuralgia: a diffusion kurtosis imaging study

OBJECTIVE

White matter microstructural abnormalities in patients with classic trigeminal neuralgia (TN) have been observed. However, the impact of classic TN in both hemispheres, the difference and extent of alterations in bilateral hemispheres, and the relationship between the impaired area and pain conduction are not fully understood. The purpose of this study was to investigate brain microstructural alterations and compare the bilateral hemispheres in patients with unilateral classic TN, as well as to explore their clinical implications.

METHODS

The authors performed a cross-sectional study of 36 patients with left classic TN (TN group; age 40-66 years) and 36 healthy controls (HC group; age 40-66 years). Diffusion kurtosis imaging (DKI; b-values = 0, 1250, and 2500 sec/mm2) was performed in all patients using a 3T MRI scanner. The FMRIB Software Library with tract-based spatial statistics was used to analyze intergroup differences in both hemispheres. Atlas-based region of interest analysis was conducted in fiber tracts and gray matter structures.

RESULTS

Decreased fractional anisotropy (FA) and increased mean diffusivity in 2.70% and 5.34% of white matter regions, such as the corona radiata, corpus callosum, internal capsule, superior longitudinal fasciculus, and cingulum, were detected in the TN group compared with the HC group (p < 0.05, family-wise error correction). Reduced mean kurtosis (MK), axial kurtosis, and radial kurtosis were detected in the bilateral thalamus in TN patients. The FA and MK values decreased asymmetrically in both cerebral hemispheres. Atlas-based region of interest analysis revealed more pronounced FA and MK reductions in the left thalamus and posterior corona radiata. There were negative associations of disease duration and pain intensity with the MK values in the thalamus, internal capsule, and superior corona radiata.

CONCLUSIONS

The authors concluded that unilateral TN could have asymmetrical microstructural alterations in bilateral hemispheres, which might be due to the compromised fiber tract integrity and abnormal neurons and synapses. The thalamus could be an important relay station in the pain conduction and modulation pathway and could have microstructural abnormalities in both the left and right sides. DKI could provide important information on the CNS pathophysiology of TN and assist in prognostic evaluation.

Effects of Size and Asymmetry on Catalase-Powered Silica Micro/nanomotors

Enzyme-powered micro/nanomotors that can autonomously move in biological environment are attractive in the fields of biology and biomedicine. The fabrication of enzyme-powered micro/nanomotors normally focuses on constructing Janus structures of micro/nanomaterials, based on the intuition that the Janus coating of enzymes can generate driving force from asymmetric catalytic reactions. Here, in the fabrication of catalase-powered silica micro/nanomotors (C-MNMs), an archetypical model of enzyme-powered micro/nanomotors, we find the silica size rather than asymmetric coating of catalase determines the motion ability of C-MNMs. The effects of size and asymmetry have been investigated by a series of C-MNMs at various sizes (0.5, 2, 5 and 10 μm) and asymmetric levels (full-, half- and most-coated with catalase). The motion performance indicates that 500 nm and 2 μm C-MNMs show obvious increases (varying from 134% to 618%) of diffusion coefficient, but C-MNMs bigger than 5 μm have no self-propulsion behaviour at all, regardless of asymmetric levels. In addition, although asymmetry facilitates enhanced diffusion of C-MNMs, only 2 μm C-MNMs are sensitive to asymmetric level. This work elucidates the primary and secondary roles of size and asymmetry in the preparation of C-MNMs, paving the way to fabricate enzyme-powered micro/nanomotors with high motion performance in future.

Can Asymmetry in Total Knee Arthroplasty Design Lead to More Normal-Like Postoperative Kinematics? A Multi-Implant Evaluation

BACKGROUND

Few studies have evaluated the effects of symmetrical versus asymmetrical implant designs, more specifically the femoral condyles, trochlear groove, joint line, and bearing surfaces. The objective of this study was to investigate multiple posterior cruciate-retaining (PCR) total knee arthroplasty (TKA) designs influencing factors related to TKA asymmetry, and to investigate whether asymmetry can improve postoperative knee kinematics.

METHODS

In vivo tibio-femoral kinematics for 99 subjects was evaluated in this retrospective study. Overall, 10 subjects had a nonimplanted, normal knee, and 89 subjects had 1 of 3 PCR TKAs with varying degrees of asymmetry within their femoral and tibial components (PCR #1 = 30, PCR #2 = 29, PCR #3 = 30). All TKAs were implanted by the same surgeon and were analyzed using fluoroscopy during a deep knee bend.

RESULTS

At full extension, all 3 PCR TKAs experienced a more posteriorized position of the femoral condyles compared to the normal knee, with the 2 asymmetrical PCR TKAs experiencing more anteriorization compared to the third, symmetrical PCR TKA. Both the normal knee and the PCR TKA with greatest amount of asymmetry experienced statistically more posterior femoral rollback of the lateral condyle than the other 2 PCR TKAs. The PCR TKA with greater asymmetry also experienced statistically greater range of motion than the other 2 PCR TKAs.

CONCLUSIONS

With increasing flexion, the design with the most asymmetry also experienced the most posterior femoral rollback, axial rotation, and greatest range of motion. The results in this study seem to suggest that the inclusion of asymmetry in a TKA could be beneficial for achieving more normal-like kinematics and greater weight-bearing knee flexion.

Exploring the Implications of Inter-Limb Asymmetries on Sprint, Agility, and Jump Performance in Young Highly-Trained Basketball Athletes: Is There a Relevant Threshold?

Background and Objectives: This study aimed to investigate the magnitude of vertical jump inter-limb asymmetries among young highly-trained basketball athletes and to analyze its impact on sport performance, specifically in sprints, agility, and vertical jumps. Materials and Methods: A unilateral countermovement jump (CMJ) was employed to determine Inter-limb Index Asymmetry (IAI) in 320 participants aged from 14 to 18 years, from the Valencia Basket youth academy. IAI was categorized into three groups: 0-9.9%, 10-14.9%, and >15%. The relationship between IAI and performance variables was analyzed through correlation studies (Pearson or Spearman's). The influence of IAI magnitude was assessed using ANOVA or Kruskal-Wallis analysis, with leg dominance as a covariable. SPSS Statistics version 26 was used for analysis. Results: Among all the participants, the mean IAI was 10.6%. Correlation studies revealed non-significant values (p < 0.05) between IAI and sport performance variables. The three IAI magnitude groups did not show statistically significant differences in sprint, agility, and jump outcomes. Leg dominance did not seem to influence performance outcomes, except for unilateral CMJ. Conclusions: The results obtained challenge the assumption that an IAI above 10% negatively affects sprint, agility, or jump performance in young basketball athletes. Notably, the magnitude of IAI did not influence sport performance parameters, suggesting that the 10-15% threshold from previous studies may not be applicable to this population. The study emphasizes the need to understand lower-limb asymmetries in the context of specific sport task performance, considering the potential evolution over time among affected young athletes.

Examining Frontal Lobe Asymmetry and Its Potential Role in Aggressive Behaviors in Early Alzheimer's Disease

Background

Neuropsychiatric symptoms (NPS) in patients with dementia lead to caregiver burdens and worsen the patient's prognosis. Although many neuroimaging studies have been conducted, the etiology of NPS remains complex. We hypothesize that brain structural asymmetry could play a role in the appearance of NPS.

Objective

This study explores the relationship between NPS and brain asymmetry in patients with Alzheimer's disease (AD).

Methods

Demographic and MRI data for 121 mild AD cases were extracted from a multicenter Japanese database. Brain asymmetry was assessed by comparing the volumes of gray matter in the left and right brain regions. NPS was evaluated using the Neuropsychiatric Inventory (NPI). Subsequently, a comprehensive assessment of the correlation between brain asymmetry and NPS was conducted.

Results

Among each NPS, aggressive NPS showed a significant correlation with asymmetry in the frontal lobe, indicative of right-side atrophy (r = 0.235, p = 0.009). This correlation remained statistically significant even after adjustments for multiple comparisons (p < 0.01). Post-hoc analysis further confirmed this association (p < 0.05). In contrast, no significant correlations were found for other NPS subtypes, including affective and apathetic symptoms.

Conclusions

The study suggests frontal lobe asymmetry, particularly relative atrophy in the right hemisphere, may be linked to aggressive behaviors in early AD. These findings shed light on the neurobiological underpinnings of NPS, contributing to the development of potential interventions.

Sparse Asymmetry in Locus Coeruleus Pathology in Alzheimer's Disease

 Tau accumulation in and neurodegeneration of locus coeruleus (LC) neurons is observed in Alzheimer's disease (AD). We investigated whether tangle and neuronal density in the rostral and caudal LC is characterized by an asymmetric pattern in 77 autopsy cases of the Rush Memory and Aging Project. We found left-right equivalence for tangle density across individuals with and without AD pathology. However, neuronal density, particularly in the caudal-rostral axis of the LC, is asymmetric among individuals with AD pathology. Asymmetry in LC neuronal density may signal advanced disease progression and should be considered in AD neuroimaging studies of LC neurodegeneration.

Inter-Rater and Test-Retest Reliability of an Innovative Evaluation Tool: CrossFit Functional Assessment Battery of Tests for the Shoulder Joint

Background and objectives This study aims to introduce an innovative functional assessment tool designed for CrossFit athletes, to identify a high risk of injury at the shoulder joint. Additionally, the study seeks to examine both inter-rater reliability, which was tested in 40 CrossFit participants, and test-retest reliability, which was assessed in twenty subjects. Methodology CrossFit Functional Assessment Battery for the Shoulder Joint (CrossFit FABS) is a newly created instrument presented for the first time. The evaluation of the performance of its six items aimed to reveal deficits that could contribute to incidents of shoulder injuries. For this purpose, 40 healthy CrossFit participants were concurrently but independently examined by two raters, and twenty healthy adults active in sports were assessed by the main investigator at two different time points. Cohen's kappa coefficient was used to analyze categorical data with an ordinal structure. Results Inter-rater reliability ranged from 0.824 to 1 (P = 0.000) and test-retest reliability was 0.661 to 0.906 (P < 0.001) for each test of CrossFit FABS. A strong to almost perfect correlation was demonstrated for all the variables between the two examiners. Moderate to almost perfect correlation was shown through test-retest procedures. Conclusions The proposed test battery was established as a reliable tool for evaluating performance routines that represent high injury-risk elements for the shoulder joint in CrossFit athletes.

Using dual-task gait to recognize Alzheimer's disease and mild cognitive impairment: a cross-sectional study

Background

Gait is a potential diagnostic tool for detecting mild cognitive impairment (MCI) and Alzheimer's disease (AD). Nevertheless, little attention has been paid to arm movements during walking, and there is currently no consensus on gait asymmetry. Therefore, in this study, we aimed to determine whether arm motion and gait asymmetry could be utilized for identifying MCI and AD.

Methods

In total, 102 middle-aged and elderly individuals were included in the final analysis and were assigned to the following three groups: AD (n = 27), MCI (n = 35), and a normal control group (n = 40). Gait and cognitive assessments were conducted for all participants. Gait detection included a single-task gait with free-speed walking and a dual-task gait with adding a cognitive task of successive minus seven to walking. Original gait parameters were collected using a wearable device featuring the MATRIX system 2.0. Gait parameters were shortened to several main gait domains through factor analysis using principal component extraction with varimax rotation. Subsequently, the extracted gait domains were used to differentiate the three groups, and the area under the receiver operating characteristic curve was calculated.

Results

Factor analysis of single-task gait identified five independent gait domains: rhythm symmetry, rhythm, pace asymmetry, arm motion, and variability. Factor analysis of the dual-task gait identified four gait domains: rhythm, variability, symmetry, and arm motion. During single-task walking, pace asymmetry was negatively correlated with MoCA scores and could distinguish between the AD group and the other two groups. Arm motion was not associated with MoCA scores, and did not exhibit adequate discrimination in either task.

Conclusion

Currently, there is no reliable evidence suggesting that arm motion can be used to recognize AD or MCI. Gait asymmetry can serve as a potential gait marker for the auxiliary diagnosis of AD but not for MCI.

Mechanical asymmetries remain low-to-moderate during 30 min of self-paced treadmill running

Introduction: We characterized the magnitude and range of gait asymmetry during self-paced treadmill running. Methods: On an instrumented treadmill, twelve trained runners (11 males, 1 female) completed a 30-min self-paced run, during which participants were instructed to cover the most distance possible. Ground reaction force recordings at a constant velocity corresponding to 70% of their maximal aerobic velocity (13.3 ± 0.8 km.h-1) allowed for the measurement of running kinetics and kinematics, as well as the calculation of spring-mass characteristics at the beginning, middle, and end of the run (minutes 1, 14, and 29, respectively). Group mean asymmetry scores were assessed using the "symmetry angle" (SA) formulae, where scores of 0% and 100% represent perfect symmetry and perfect asymmetry, respectively. Results: There was no time effect on SA scores for any of the 13 biomechanical variables (p ≥ 0.128). Mean SA scores were <2.5% for contact time (0.8% ± 0.7%), flight time (1.4% ± 0.6%), step frequency (0.7% ± 0.3%), duty factor (0.7% ± 0.3%), duration of braking (1.3% ± 0.7%) and push-off phases (0.9% ± 0.8%), as well as peak braking (2.3% ± 1.3%) and push-off forces (1.4% ± 0.9%). Mean SA scores were ≥2.5% for peak vertical loading rate (3.1% ± 1.7%), mean vertical loading rate (3.4% ± 2.1%), peak vertical forces (2.9% ± 2.2%), as well as vertical stiffness (5.2% ± 3.5%) and leg stiffness (2.5% ± 1.5%). Conclusion: Throughout a 30-min running time trial, there were consistently low-to-moderate mechanical asymmetries for spatiotemporal variables, kinetics, and spring-mass model characteristics. This suggests that trained runners maintained relatively even strides during the self-paced treadmill run, with lower extremities behaving similarly when controlling for velocity.

Reduced Lateralization of Multiple Functional Brain Networks in Autistic Males

Background

Autism spectrum disorder has been linked to a variety of organizational and developmental deviations in the brain. One such organizational difference involves hemispheric lateralization, which may be localized to language-relevant regions of the brain or distributed more broadly.

Methods

In the present study, we estimated brain hemispheric lateralization in autism based on each participant's unique functional neuroanatomy rather than relying on group-averaged data. Additionally, we explored potential relationships between the lateralization of the language network and behavioral phenotypes including verbal ability, language delay, and autism symptom severity. We hypothesized that differences in hemispheric asymmetries in autism would be limited to the language network, with the alternative hypothesis of pervasive differences in lateralization. We tested this and other hypotheses by employing a cross-sectional dataset of 118 individuals (48 autistic, 70 neurotypical). Using resting-state fMRI, we generated individual network parcellations and estimated network asymmetries using a surface area-based approach. A series of multiple regressions were then used to compare network asymmetries for eight significantly lateralized networks between groups.

Results

We found significant group differences in lateralization for the left-lateralized Language (d = -0.89), right-lateralized Salience/Ventral Attention-A (d = 0.55), and right-lateralized Control-B (d = 0.51) networks, with the direction of these group differences indicating less asymmetry in autistic individuals. These differences were robust across different datasets from the same participants. Furthermore, we found that language delay stratified language lateralization, with the greatest group differences in language lateralization occurring between autistic individuals with language delay and neurotypical individuals.

Limitations

The generalizability of our findings is restricted due to the male-only sample and greater representation of individuals with high verbal and cognitive performance.

Conclusions

These findings evidence a complex pattern of functional lateralization differences in autism, extending beyond the Language network to the Salience/Ventral Attention-A and Control-B networks, yet not encompassing all networks, indicating a selective divergence rather than a pervasive one. Furthermore, a differential relationship was identified between Language network lateralization and specific symptom profiles (namely, language delay) of autism.

Symmetry and asymmetry in atherosclerosis

Atherosclerosis remains the main cause of death worldwide. Most important issues concerning atherosclerosis are hemodynamics and how it affects plaque prevalence and distribution, as well as the symmetry and asymmetry of vasculature and plaques. To present the symmetry in the vascular system an analysis of PubMed and MEDLINE databases was performed. As of February 21, 2023, the results were as follows: for "symmetry" AND "atherosclerosis" there were 47 results; for "symmetry" AND "atherosclerotic lesions" - 20 results; for "symmetry" AND "artery stenosis" - 82 results; for "asymmetry" AND "atherosclerosis" - 87 results. Not without meaning are preventive measures. In the light of the Fourth Industrial Revolution artificial intelligence (AI) solutions help to develop new tools outperforming already existing cardiovascular risk scales. The aim of this paper is to present a current view on symmetry within vasculature and atherosclerosis as well as present a new approach to assess individuals' cardiovascular risk in accordance with precision medicine assumptions. Symmetry and asymmetry within the human vascular system play a crucial role in understanding of arterial diseases, including atherosclerosis. Moreover, it is unavoidable to use AI in cardiovascular risk stratification. Int J Occup Med Environ Health. 2023;36(6):693-703.

Development of soft tissue asymmetry indicators to characterize aging and functional mobility

Introduction: The aging population poses significant challenges to healthcare systems globally, necessitating a comprehensive understanding of age-related changes affecting physical function. Age-related functional decline highlights the urgency of understanding how tissue composition changes impact mobility, independence, and quality of life in older adults. Previous research has emphasized the influence of muscle quality, but the role of tissue composition asymmetry across various tissue types remains understudied. This work develops asymmetry indicators based on muscle, connective and fat tissue extracted from cross-sectional CT scans, and shows their interplay with BMI and lower extremity function among community-dwelling older adults. Methods: We used data from 3157 older adults from 71 to 98 years of age (mean: 80.06). Tissue composition asymmetry was defined by the differences between the right and left sides using CT scans and the non-Linear Trimodal Regression Analysis (NTRA) parameters. Functional mobility was measured through a 6-meter gait (Normal-GAIT and Fast-GAIT) and the Timed Up and Go (TUG) performance test. Statistical analysis included paired t-tests, polynomial fitting curves, and regression analysis to uncover relationships between tissue asymmetry, age, and functional mobility. Results: Findings revealed an increase in tissue composition asymmetry with age. Notably, muscle and connective tissue width asymmetry showed significant variation across age groups. BMI classifications and gait tasks also influenced tissue asymmetry. The Fast-GAIT task demonstrated a substantial separation in tissue asymmetry between normal and slow groups, whereas the Normal-GAIT and the TUG task did not exhibit such distinction. Muscle quality, as reflected by asymmetry indicators, appears crucial in understanding age-related changes in muscle function, while fat and connective tissue play roles in body composition and mobility. Discussion: Our study emphasizes the importance of tissue asymmetry indicators in understanding how muscle function changes with age in older individuals, demonstrating their role as risk factor and their potential employment in clinical assessment. We also identified the influence of fat and connective tissue on body composition and functional mobility. Incorporating the NTRA technology into clinical evaluations could enable personalized interventions for older adults, promoting healthier aging and maintaining physical function.

Normative Database of the Superior-Inferior Thickness Asymmetry for All Inner and Outer Macular Layers of Adults for the Posterior Pole Algorithm of the Spectralis SD-OCT

BACKGROUND

This study aims to establish a reference for the superior-inferior hemisphere asymmetry in thickness values for all macular layers for the posterior pole algorithm (PPA) available for the Spectralis SD-OCT device.

METHODS

We examined 300 eyes of 300 healthy Caucasian volunteers aged 18-84 years using the PPA, composed of a grid of 64 (8 × 8) cells, to analyze the thickness asymmetries of the following automatically segmented macular layers: retinal nerve fiber layer (RNFL); ganglion cell layer (GCL); inner plexiform layer (IPL); inner nuclear layer (INL); outer plexiform layer (OPL); outer nuclear layer (ONL); retinal pigment epithelium (RPE); inner retina; outer retina; complete retina. Mean ± standard deviation and the 2.5th and 97.5th percentiles of the thickness asymmetry values were obtained for all the corresponding cells.

RESULTS

All the macular layers had significant superior-inferior thickness asymmetries. GCL, IPL, INL, ONL and RPE showed significantly greater thicknesses in the superior than the inferior hemisphere, whereas RNFL and OPL were thicker in the inferior hemisphere. The largest differences between hemispheres were for RNFL and ONL.

CONCLUSIONS

This is the first normative database of macular thickness asymmetries for the PPA and should be considered to distinguish normal from pathological values when interpreting superior-inferior macular asymmetries.

Evidence for a Compensatory Relationship between Left- and Right-Lateralized Brain Networks

The two hemispheres of the human brain are functionally asymmetric. At the network level, the language network exhibits left-hemisphere lateralization. While this asymmetry is widely replicated, the extent to which other functional networks demonstrate lateralization remains a subject of Investigation. Additionally, it is unknown how the lateralization of one functional network may affect the lateralization of other networks within individuals. We quantified lateralization for each of 17 networks by computing the relative surface area on the left and right cerebral hemispheres. After examining the ecological, convergent, and external validity and test-retest reliability of this surface area-based measure of lateralization, we addressed two hypotheses across multiple datasets (Human Connectome Project = 553, Human Connectome Project-Development = 343, Natural Scenes Dataset = 8). First, we hypothesized that networks associated with language, visuospatial attention, and executive control would show the greatest lateralization. Second, we hypothesized that relationships between lateralized networks would follow a dependent relationship such that greater left-lateralization of a network would be associated with greater right-lateralization of a different network within individuals, and that this pattern would be systematic across individuals. A language network was among the three networks identified as being significantly left-lateralized, and attention and executive control networks were among the five networks identified as being significantly right-lateralized. Next, correlation matrices, an exploratory factor analysis, and confirmatory factor analyses were used to test the second hypothesis and examine the organization of lateralized networks. We found general support for a dependent relationship between highly left- and right-lateralized networks, meaning that across subjects, greater left lateralization of a given network (such as a language network) was linked to greater right lateralization of another network (such as a ventral attention/salience network) and vice versa. These results further our understanding of brain organization at the macro-scale network level in individuals, carrying specific relevance for neurodevelopmental conditions characterized by disruptions in lateralization such as autism and schizophrenia.

Frontal EEG alpha asymmetry in youth with autism: Sex differences and social-emotional correlates

In youth broadly, EEG frontal alpha asymmetry (FAA) associates with affective style and vulnerability to psychopathology, with relatively stronger right activity predicting risk for internalizing and externalizing behaviors. In autistic youth, FAA has been related to ASD diagnostic features and to internalizing symptoms. Among our large, rigorously characterized, sex-balanced participant group, we attempted to replicate findings suggestive of altered FAA in youth with an ASD diagnosis, examining group differences and impact of sex assigned at birth. Second, we examined relations between FAA and behavioral variables (ASD features, internalizing, and externalizing) within autistic youth, examining effects by sex. Third, we explored whether the relation between FAA, autism features, and mental health was informed by maternal depression history. In our sample, FAA did not differ by diagnosis, age, or sex. However, youth with ASD had lower total frontal alpha power than youth without ASD. For autistic females, FAA and bilateral frontal alpha power correlated with social communication features, but not with internalizing or externalizing symptoms. For autistic males, EEG markers correlated with social communication features, and with externalizing behaviors. Exploratory analyses by sex revealed further associations between youth FAA, behavioral indices, and maternal depression history. In summary, findings suggest that individual differences in FAA may correspond to social-emotional and mental health behaviors, with different patterns of association for females and males with ASD. Longitudinal consideration of individual differences across levels of analysis (e.g., biomarkers, family factors, and environmental influences) will be essential to parsing out models of risk and resilience among autistic youth.

Characterization of Cortical and Subcortical Structural Brain Asymmetry in Adults with and without Dyslexia

Multiple cortical (planum temporale, supramarginal gyrus, fusiform gyrus) and subcortical (caudate, putamen, and thalamus) regions have shown different functional lateralization patterns for skilled vs. dyslexic readers. The extent to which skilled and dyslexic adult readers show differential structural lateralization remains to be seen. Method: Participants included 72 adults (N = 41 skilled; N = 31 dyslexic) who underwent a high-resolution MRI brain scan. The grey matter volume of the cortical and subcortical structures was extracted. Results: While there were clear behavioral differences between the groups, there were no differences in any of the isolated structures (i.e., either total size or asymmetry index) and limited evidence for any brain-behavior relationships. We did find a significant cortical-cortical relationship (p = 0.006) and a subcortical-subcortical relationship (p = 0.008), but not cross-over relationships. Overall, this work provides unique information on neural structures as they relate to reading in skilled and dyslexic readers.

Topography of the infraorbital foramen in human skulls originating from different time periods

BACKGROUND

The infraorbital foramen (IOF) is present on the maxilla under the infraorbital margin. Its identification is essential in various surgical procedures. The main aim of this study was the morphometric assessment of the position of the right and left infraorbital foramina in relation to specific structural elements of the facial skeleton, their width and direction, and also the determination of the location of these foramina above maxillary teeth in examined male skulls (belonging to European populations) dated to the beginning of the 20th century and the medieval and post-medieval period. This aim concerned also the assessment of the symmetry of the examined foramina (their location and size). An additional goal was to determine differences between the cranial samples concerning the analysed traits.

MATERIALS AND METHODS

The six metric and two non-metric traits concerning the IOF were collected from the male cranial samples including modern skulls (n = 87), the medieval and post-medieval skulls (from 13th centuries and 15-17th centuries, respectively; n = 47) obtained from archaeological excavations in Wroclaw, and the sample of the medieval skulls (11-13th centuries, n = 100) from Sypniewo. The sex and age of the specimens were determined using the standard methodology. The appropriate statistical analysis was performed.

RESULTS

Significant differences were established for three traits (taken from the left and right side) in the case of modern skulls (diameter of IOF, its distance to the midline, and zygomaticomaxillary suture) and one in the case of medieval skulls from Sypniewo (distance to the midline). In all of the cranial samples IOF most frequently occurred above the first upper molar. The greater diameter of IOF and its shorter distance to the alveolar crest and nasal notch were observed in non-modern skulls compared to modern skulls.

CONCLUSIONS

The results of this study provide new additional data on the topography of IOF and its asymmetry, confirm the presence of both geographical and chronological differences between populations, and can be used in dental practice, and forensic odontology in the analysis of archaeological bone materials.

Variability analysis of muscle activation symmetry to identify indicators of individual motor strategy: a case series on elite Paralympic powerlifters

Introduction

In Paralympic powerlifting competitions, movement execution symmetry is a technical requirement influenced by individual athlete characteristics and motor strategies. Identifying the elements associated with individual motor strategies can offer valuable insight for improving sport performance. Therefore, this case series study aimed to explore muscle activation symmetry and its intra- and inter-individual variability to determine the muscles mostly related to individual motor strategies in elite Paralympic powerlifters.

Methods

Bilateral electromyographic activation of the anterior deltoid (AD), pectoralis major (PM), latissimus dorsi (LD), triceps (TRI) and external oblique (EO) muscles were analysed in five elite Paralympic powerlifters while performing four sets of one-repetition maximum of Paralympic bench press. Muscle activation symmetry indexes (SI) were obtained and transformed to consider individual-independent evaluation. The coefficient of variation (CV), variance ratio (VR), and mean deviation (MD) were computed to assess inter- and intra-individual variability in electromyographic waveforms and SI.

Results

Both transformed and non-transformed SI indicated overall symmetric activation in DA, PM, TRI, and LD. Transformed SI revealed asymmetrical muscle activation of EO when grouping data (mean bilateral difference: 10%). Athletes exhibited low intra-individual SI variability in all analysed muscles (CV < 10%) and low inter-individual variability in DA, PM, LD, and TRI (CV < 10%; VR: 4%-11%; MD: 29%-43%). In contrast, higher inter-individual variability was observed in EO (CV: 23%; VR: 23%; MD: 72%-81%).

Conclusion

The highest variability and asymmetry in abdominal muscle activation among athletes emphasize the importance of personalized training approaches for targeting these muscles due to their role in individualizing motor strategies.

Spatial heterogeneity of biomass turnover has contrasting effects on synchrony and stability in trophic metacommunities

Spatial heterogeneity is a fundamental feature of ecosystems, and ecologists have identified it as a factor promoting the stability of population dynamics. In particular, differences in interaction strengths and resource supply between patches generate an asymmetry of biomass turnover with a fast and a slow patch coupled by a mobile predator. Here, we demonstrate that asymmetry leads to opposite stability patterns in metacommunities receiving localized perturbations depending on the characteristics of the perturbed patch. Perturbing prey in the fast patch synchronizes the dynamics of prey biomass between the two patches and destabilizes predator dynamics by increasing the predator's temporal variability. Conversely, perturbing prey in the slow patch decreases the synchrony of the prey's dynamics and stabilizes predator dynamics. Our results have implications for conservation ecology and suggest reinforcing protection policies in fast patches to dampen the effects of perturbations and promote the stability of population dynamics at the regional scale.

Accuracy of ultrasound signs on two-dimensional transvaginal ultrasound in prediction of adenomyosis: prospective multicenter study

OBJECTIVE

Two-dimensional (2D) transvaginal ultrasound (TVS) is an accessible and cost-effective diagnostic tool for the detection of adenomyosis. Different ultrasound features related to adenomyosis have been described, but the predictive value of each ultrasound sign and their combinations requires further investigation. We aimed to analyze the accuracy of 2D-TVS and describe possible combinations of ultrasound signs with a high predictive value in the diagnosis of adenomyosis.

METHODS

This was a prospective multicenter study of patients scheduled for laparoscopic hysterectomy who had been examined using standardized 2D-TVS at nine expert centers specializing in the diagnosis and treatment of endometriosis. 2D-TVS examination included nine typical adenomyosis ultrasound features, comprising heterogeneous myometrium, myometrial linear striations, myometrial cysts, subendometrial microcysts, asymmetrical myometrial thickening, uterine enlargement, the 'question mark sign', thickening of the junctional zone and hyperechoic myometrial spots, in order to predict or exclude the presence of adenomyosis. Ultrasound examination results were compared with histology after hysterectomy. The diagnostic reliability of the nine ultrasound signs and their combinations, and the influence of concurrent fibroids on the accuracy of the results, were analyzed.

RESULTS

A total of 202 patients were enrolled into the study. Histopathological examination revealed adenomyosis in 130 patients (64.4%). The accuracy of prediction of adenomyosis by 2D-TVS examination using all signs was 63.4% (positive predictive value, 71.5%; negative predictive value, 48.6%; sensitivity, 71.5%; specificity, 48.6%). Heterogeneous myometrium, myometrial cysts, subendometrial microcysts and hyperechoic myometrial spots showed the highest accuracy (55.7-62.1%) as individual ultrasound signs for the prediction of adenomyosis. The combination of the most accurate ultrasound signs (subendometrial microcysts, myometrial cysts and heterogeneous myometrium) improved the specificity of prediction (86.1%) when compared with that of these three single markers (35.2-81.7%). Uterine enlargement and asymmetry showed both low sensitivity (60.8% and 52.3%, respectively) and specificity (41.7% and 49.3%, respectively) as individual sonographic signs.

CONCLUSIONS

Heterogeneous myometrium, myometrial cysts, subendometrial microcysts and hyperechoic myometrial spots showed the highest accuracy for the detection of adenomyosis in this study, while uterine enlargement and asymmetry led to high false-positive and false-negative results. A combination of ultrasound features including the most accurate signs increases specificity. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Associations of handgrip weakness and asymmetry with new-onset stroke in Chinese middle-aged and older adults: a cohort study

Background

Weak handgrip strength (HGS) has been linked to adverse health outcomes including stroke. However, the joint associations of HGS weakness and asymmetry between limbs with stroke incidence remain underexplored.

Methods

This cohort study analyzed data of participants aged ≥45 years from three waves (2011, 2013, and 2015) of the China Health and Retirement Longitudinal Study. Weak HGS was defined according to the recommendation of European Working Group on Sarcopenia in Older People. Asymmetric HGS was defined if the HGS ratio of both hands was over 1.1 or below 0.9. New-onset stroke was confirmed through self-report of physician's diagnosis.

Results

A total of 10,966 participants without stroke at baseline were included in the analysis. During the 4 years follow-up, there were 262 (2.39%) new-onset stroke cases. Compared to individuals with non-weak and symmetric HGS, those with HGS asymmetry alone and weakness alone were associated with hazards of 1.09 (95% confidence interval [CI]: 0.80-1.48) and 1.27 (95%CI: 0.86-1.88) for new-onset stroke, respectively, while co-occurrence of both HGS asymmetry and weakness was associated with 1.80 (95%CI: 1.24-2.60) greater hazard for new-onset stroke after controlling for confounders. Such associations were consistent in older adults aged ≥60 years, but not in those aged<60 years.

Conclusion

Individuals with both weak and asymmetric HGS tended to have greater risk of new-onset stroke, compared to those with normal HGS, or with either weak or asymmetric HGS alone. Our finding suggested that examining HGS asymmetry alongside weakness may help to improve the risk-stratification and target prevention of stroke, particularly in the older population.

Neuropsychiatric symptoms and imbalance of atrophy in behavioral variant frontotemporal dementia

Behavioral variant frontotemporal dementia is characterized by heterogeneous frontal, insular, and anterior temporal atrophy patterns that vary along left-right and dorso-ventral axes. Little is known about how these structural imbalances impact clinical symptomatology. The goal of this study was to assess the frequency of frontotemporal asymmetry (right- or left-lateralization) and dorsality (ventral or dorsal predominance of atrophy) and to investigate their clinical correlates. Neuropsychiatric symptoms and structural images were analyzed for 250 patients with behavioral variant frontotemporal dementia. Frontotemporal atrophy was most often symmetric while left-lateralized (9%) and right-lateralized (17%) atrophy were present in a minority of patients. Atrophy was more often ventral (32%) than dorsal (3%) predominant. Patients with right-lateralized atrophy were characterized by higher severity of abnormal eating behavior and hallucinations compared to those with left-lateralized atrophy. Subsequent analyses clarified that eating behavior was associated with right atrophy to a greater extent than a lack of left atrophy, and hallucinations were driven mainly by right atrophy. Dorsality analyses showed that anxiety, euphoria, and disinhibition correlated with ventral-predominant atrophy. Agitation, irritability, and depression showed greater severity with a lack of regional atrophy, including in dorsal regions. Aberrant motor behavior and apathy were not explained by asymmetry or dorsality. This study provides additional insight into how anatomical heterogeneity influences the clinical presentation of patients with behavioral variant frontotemporal dementia. Behavioral symptoms can be associated not only with the presence or absence of focal atrophy, but also with right/left or dorsal/ventral imbalance of gray matter volume.

Surgical Correction of Post-traumatic Residual Deformity of the Mandible: A Case Report

Mandibular fractures are the most common trauma cases that we often come across in our day-to-day practice of oral and maxillofacial surgery. Various factors can lead to deformities and make those cases more challenging, which includes a delay in surgical treatment, resulting in non-union or malunion of the fracture site causing occlusal disturbances and functional abnormalities in the temporomandibular joint.

Structural asymmetry in biotic interactions as a tool to understand and predict ecological persistence

A universal feature of ecological systems is that species do not interact with others with the same sign and strength. Yet, the consequences of this asymmetry in biotic interactions for the short- and long-term persistence of individual species and entire communities remains unclear. Here, we develop a set of metrics to evaluate how asymmetric interactions among species translate to asymmetries in their individual vulnerability to extinction under changing environmental conditions. These metrics, which solve previous limitations of how to independently quantify the size from the shape of the so-called feasibility domain, provide rigorous advances to understand simultaneously why some species and communities present more opportunities to persist than others. We further demonstrate that our shape-related metrics are useful to predict short-term changes in species' relative abundances during 7 years in a Mediterranean grassland. Our approach is designed to be applied to any ecological system regardless of the number of species and type of interactions. With it, we show that is possible to obtain both mechanistic and predictive information on ecological persistence for individual species and entire communities, paving the way for a stronger integration of theoretical and empirical research.

Asymmetry of Characteristics of the Right-Left Hemodynamic Balance of Microcirculation in the Temporal Skin Areas of the Head in Young Male and Female Subjects

The indices of asymmetry of microcirculation in the skin of the temporal areas of the head in young male and female subjects were studied. In 20 healthy volunteers (10 men and 10 women, age 18-19 years), synchronous measurements of the microcirculation of the skin of the symmetrical temporal areas of the head were carried out by laser Doppler flowmetry. The coefficients of asymmetry of regression relationships between perfusion changes in each side and initial perfusion values in both the same and opposite sides, the distribution function of perfusion asymmetry coefficients, and variability of perfusion in the studied areas were analyzed. The sex differences of the measured characteristics of asymmetry were revealed. In men, the distribution functions of perfusion asymmetry are pointed, with positive excesses, and in women they were flat, with negative excesses. In female subjects, the contribution of the right microcirculatory bed to the right-left hemodynamic balance was higher. These findings support the hypothesis on greater plasticity of the female brain in comparison with the male brain.

Exploring Asymmetric Fine Motor Impairment Trends in Early Parkinson's Disease via Keystroke Typing

Background

The nQiMechPD algorithm transforms natural typing data into a numerical index that characterizes motor impairment in people with Parkinson's Disease (PwPD).

Objectives

Use nQiMechPD to compare asymmetrical progression of PD-related impairment in dominant (D-PD) versus non-dominant side onset (ND-PD) de-novo patients.

Methods

Keystroke data were collected from 53 right-handed participants (15 D-PD, 13 ND-PD, 25 controls). We apply linear mixed effects modeling to evaluate participants' right, left, and both hands nQiMechPD relative change by group.

Results

The 6-month nQiMechPD trajectories of right (**P = 0.002) and both (*P = 0.043) hands showed a significant difference in nQiMechPD trends between D-PD and ND-PD participants. Left side trends were not significantly different between these two groups (P = 0.328).

Conclusions

Significant differences between D-PD and ND-PD groups were observed, likely driven by contrasting dominant hand trends. Our findings suggest disease onset side may influence motor impairment progression, medication response, and functional outcomes in PwPD.