Communication and cognitive impairments are common impediments to participation and social functioning in children with cerebral palsy (CP). Bilateral language networks underlie the function of some high-level language-related cognitive functions.To explore the association between receptive vocabulary and white-matter microstructure in the temporal lobes and the central part of the temporo-temporal bundles in children with CP.37 children with spastic motor type CP  underwent a receptive vocabulary test  and 3T MRI. Mean fractional anisotropy (FA) and mean diffusivity (MD) were calculated for the temporal lobes and the interhemispheric bundles traversing the splenium of the corpus callosum and the anterior commissure. Associations between microstructure and receptive vocabulary function were explored using univariable linear regression.PPVT-IV scores were significantly associated with mean white matter MD in the left temporal lobe, but not the right temporal lobe. There was no association between PPVT-IV and mean white matter FA in the temporal lobes. PPVT-IV scores were not significantly associated with the laterality of these diffusion tensor metrics. Within the corpus callosum, FA, but not MD of the temporo-temporal bundles was significantly associated with the PPVT-IV scores. Within the anterior commissure no equivalent relationship between diffusion metrics and PPVT-IV was found.Our findings add further understanding to the pathophysiological basis underlying receptive vocabulary skills in children with CP that could extend to other patients with early brain damage. This study highlights the importance of interhemispheric connections for receptive vocabulary. Cerebral palsy (CP) is the most common cause of physical disability in childhood, affecting 2.11 per 1000 live births worldwide . ComorbiMore than 55% of children with CP present some level of communication impairment , 10. TheMagnetic resonance imaging (MRI) contributes to our understanding of the pathological basis underlying CP and clinical outcomes  includinIn typically developing persons language is predominantly processed in the left hemisphere, while in persons with CP some degree of plasticity has been reported by functional MRI studies , 27. ThaIn a previous study , we founWhite matter (WM) injury is a very common lesion pattern in spastic motor type CP , due to Adding to this, diffuse thinning of the corpus callosum in nonverbal children with severe CP appears to be associated with poor spoken language comprehension . A seconTo our knowledge, the association between the WM integrity of interhemispheric fibres connecting the temporal lobes and receptive vocabulary has not been studied in children with CP. In the present study we expand on our previous study by investigating microstructural properties, rather than the MRI observable lesion load. We aim to explore the association between receptive vocabulary and 1) FA/MD in the right and left temporal lobes; 2) the FA/MD laterality index for the temporal lobes and 3) the structural connectivity between temporal lobes.Participants were recruited as part of a cohort study of participants with CP at the Queensland Cerebral Palsy and Rehabilitation Research Centre at the University of Queensland , the “Comprehensive surveillance to PREDICT outcomes for school age children with CP”  . The UniThe present study includes 37 participants recruited as part of this study who presented with spastic CP motor type, underwent the receptive vocabulary assessment, and presented with observable brain lesions in the current or previous clinical brain MRI. th version of Peabody Picture Vocabulary Test (PPVT-IV), a proxy for verbal IQ [Receptive (hearing) vocabulary was assessed by the 4erbal IQ . This coerbal IQ . As it derbal IQ  and it herbal IQ .MRI data were acquired at study enrolment using a 3T Siemens Magnetom PRISMA. Imaging included 3D T1-weighted Magnetisation Prepared Rapid Gradient Echo (MPRAGE) and diffusion weighted imaging. The MPRAGE scanning parameters were TR = 1900 ms, TE = 2.98 ms, TI = 900 ms, flip angle = 9 degrees, resolution = 1.0x1.0x1.0 mm.2 and 64 directions at b = 3000 s/mm2, along with 12 non-diffusion-weighted images. Diffusion encoding directions were uniformly distributed within each shell. Directions and b-values were acquired in an order that resulted in near-optimal distribution in case of truncation. The full diffusion protocol was divided into 4 unique blocks of equal length, with 2 blocks acquired with phase encoding along anterior to posterior and 2 blocks acquired with phase encoding along posterior to anterior. This implementation enabled (i) repetition of individual blocks if excessive motion was observed, and (ii) correction for susceptibility-induced image distortions using reverse phase-encoded images. Other acquisition parameters were: TR/TE 4700/84ms, multi-band factor 2, resolution 2 x 2 mm, slice thickness 2 mm. Acquisition time of each block was 2:07 minutes, i.e. 8:28 minutes total.Multi-shell diffusion MRI data were acquired at 2 b-values: 20 directions at b = 1000 s/mmBrain lesion severity was assessed using the semi-quantitative scale for structural MRI (sqMRI) to better understand participants’ observable brain lesion characteristics. The sqMRI scale is valid  and reliIntensity bias in the structural MRI was corrected using the N4 algorithm , while iTissue segmentation was performed using the Expectation Maximization (EM)/Markov Random Fields (MRF)  on the TDiffusion MRI data were cropped tightly around the head to reduce processing times. Images were denoised using Marchenko-Pastur PCA  implemenDiffusion tensors were estimated separately for each shell using iterated weighted least-squares of the log-signal , as implDiffusion and structural images were rigidly aligned using boundary-based registration , as implInterhemispheric bundles traversing (a) the splenium of the corpus callosum or (b) the anterior commissure and connecting the temporal lobes were generated using MRtrix’ iFOD2 probabilistic tractography algorithm.Streamlines were seeded from a region of interest (ROI)  in the mid-sagittal slice, or the slice closest to the mid-sagittal slice if the anatomy was not clear on the mid-sagittal slice. These ROIs were manually traced on the FA images, with the splenium of the corpus callosum ROI being guided by the previously detailed parcellation. The inclusion (and termination) ROI was the GM/WM interface of the temporal lobe, calculated directly from the parcellation and segmentation. We opted to perform tractography of the left and right hemispheres separately as this proved substantially more computationally efficient than tracking bilaterally, with no visible impact on the quality of the resulting tractography. When delineating the left hemisphere, the entire right hemisphere was an explicit exclusion mask, and vice versa. A manually drawn exclusion ROI was used for both corpus callosum and anterior commissure tracts to prevent streamlines passing through the occipital, frontal and parietal lobes. Anterior-commissure streamlines also explicitly excluded the fornix, as delineated by the automatic parcellation. All streamlines had a maximum length of 125mm on either hemisphere. All other settings were left at default values. For each hemisphere a minimum of 5000 streamlines were generated and the resulting tractograms were combined using MRtrix’ tckedit . FinallyMean FA and MD of the interhemispheric connections were measured at the level of the splenium of the corpus callosum or the anterior commissure to avoid the confounding effects of crossing fibres that are in voxels further from the mid-sagittal plane . SpecifiThe associations between PPVT-IV scores and mean FA or MD in the temporal lobe were explored with univariable linear regressions (Aim 1). FA/MD temporal lobe laterality indices were similarly regressed against PPVT-IV scores univariably (Aim 2). FA/MD temporal lobe laterality indices ranged from -1 to 1 with a score approximating zero indicating a more similar WM microstructure between temporal lobes; a score approaching ‘one’ indicating higher right-sided FA/MD values and a score approaching ‘negative one’ indicating lower right-sided FA/MD values. Finally, the associations between mean FA/MD around the midline in the commissural bundles connecting the temporal lobes and PPVT-IV scores were explored with univariable linear regression models (Aim 3).Age and sex were not significantly associated with any brain measure used in the analysis. Given that, and that the PPVT-IV scores are age-adjusted, age and sex were not included as a covariable in our analysis. The normality of the residuals was checked by using scatterplots, histograms and the Kolmogorov-Smirnov test. No datapoints were rejected as outliers. Significance level was set at 0.05 and data were analysed with the Statistical Package for the Social Sciences  . MultiplDemographic and clinical characteristics of the sample are presented in Results from the linear regression models relating to Aims 1 and 2 are presented in FA, but not MD, in the central part of the temporo-temporal bundles traversing the splenium of the corpus callosum was significantly associated with the PPVT-IV scores . Neither FA nor MD in the central part of the temporo-temporal bundles traversing the anterior commissure where significantly associated with the PPVT-IV scores  . The assIn this study we explored in depth the association between receptive vocabulary skills and WM microstructure within the temporal lobes and the commissural fibres connecting them in children with spastic motor type CP. We found that the lower the MD of the left temporal lobe, the better the receptive vocabulary performance. Vocabulary performance was not significantly associated with mean FA in the temporal lobe WM nor mean MD in the right temporal lobe WM. PPVT-IV scores were also not significantly associated with the laterality of these FA/MD indices. Within the corpus callosum, FA, but not MD, of the temporo-temporal bundles were positively and significantly associated with the PPVT-IV scores. Within the anterior commissure no equivalent relationship between diffusion metrics and PPVT-IV was found.Despite clear patterns of injury, our participants presented with a mean standardized PPVT-IV score within the normal limits see . This isUnlike the significant association between the lesion temporal lobe laterality index and PPVT-IV found in our previous study , here thThe corpus callosum, and especially its posterior part, is a common region involved in our sample. This has also been identified in several diffusion studies but not all , 39, 40.Consistently, in healthy children, larger volumes of the posterior parts of the posterior corpus callosum have been shown to be associated with better vocabulary and increased interhemispheric language network connectivity . This seWe found a significant association with MD, but not FA, for the whole left temporal lobe while finding the reverse for the temporo-temporal bundles within the splenium of the corpus callosum. It is likely that this reflects the strengths and limitations of these measures. Specifically, the calculation of FA from the diffusion tensor model is driven by the majority direction of fibres in each voxel, while the calculation of MD is simply the average diffusivity. Within the corpus callosum where WM fibres are unidirectional (i.e. high FA), FA may provide a more sensitive measure of microstructure than MD. By contrast, in the temporal lobe voxels with predominantly contain crossing fibres , MD is tWithin the anterior commissure, no equivalent relationship between diffusion metrics and PPVT-IV was found. The association between the size of the anterior commissure and severity of language impairments has been described in preterm adolescents who also presented with volume reductions in the splenium of the corpus callosum . InteresAlthough the main limitation of the present study is its moderate sample size, it is sufficient to identify effects as small as 0.18 in the generated linear regression models with 80% confidence. Our current sample has value amongst existing literature as samples of this size and type are unusual in the CP literature because neuroimaging and neuropsychological assessments are extremely challenging to conduct in this population. Another limitation is that language lateralization was not confirmed in our participants and having such information would allow a more comprehensive interpretation of our results. Additionally, it must be remembered that CP is a heterogenous group of conditions, and different mechanisms of recovery are known for several functions between participants with bilateral or solely unilateral brain lesions. Given our cohort , resultsThe findings of our study add further understanding to the pathophysiological bases underlying receptive vocabulary skills in children with CP that could extend to other patients with early brain damage. This study complements our previous findings that used a semiquantitative measure of brain lesion severity and highlights the importance of interhemispheric connections for receptive vocabulary. This knowledge contributes to the ultimate goal of better predicting early in life cognitive functioning based on brain characteristics in order to provide early and individualized interventions.S1 TableB: regression coefficient; *p ≤ 0.05; FA: fractional anisotropy; MD: mean diffusivity; CI: confidence interval.(PDF)Click here for additional data file.S1 Data(XLSX)Click here for additional data file.


Cell Stem Cell, employ a FUCCI- and MADM-based system to screen for small molecules combinations that produced a collaborative effect on cardiomyocyte cycling and cytokinesis. The authors generate a cocktail of five small molecules that increase cardiomyocyte proliferation and regeneration in vitro and in vivo with high efficiency, and explore its potential in cardiac regenerative repair after myocardial infarction through a new potential pathway for cardiomyocyte cell-cycle re-entry.Adult mammalian cardiomyocytes are unable to proliferate to regenerate lost tissue after heart injury. Du et al., reporting in  Heart disease is the leading cause of death across the globe, owing to the inability of the adult human heart to functionally regenerate after injury. This lack of regenerative ability is thought to be shared by the majority of adult mammals, as mammalian cardiomyocytes undergo cell cycle exit during development and lose their ability to proliferate to replace any lost or damaged tissue following injury - based system to report cell cycle activity in isolated neonatal rat cardiomyocytes, Du et al. were able to identify 13 candidate small molecules by screening 564 small molecules by their effect on cardiomyocyte proliferation. Next, they tested the pairwise effects of these 13 candidate small molecules on cardiomyocyte cell-cycle re-entry. They developed a maximal connectivity algorithm to create interactive networks based on the collaborative effects of small molecule pairs to identify small molecules with high connectivity and synergy, resulting in the identification of ten small molecule combinations that were predicted to have the strongest interactions. These ten cocktails were tested against each other in the same FUCCI system to assess cell cycle re-entry into S/G2/M phases, but also through a Mosaic Analysis with Double Markers (MADM)- based system to identify successful cytokinesis  in vitro, Du et al. explored the effectiveness of 5SM on cardiomyocyte proliferation and regeneration in vivo. They used immunostaining to show that 5SM increased cardiomyocyte proliferation after intramyocardial injection in adult rat hearts, and examined a MADM mouse line to observe the increase in cardiomyocyte cytokinesis after 5SM treatment in vivo. Additionally, Du et al. found that 5SM largely increased the percentage of cardiomyocytes that expressed cell-cycle markers within the injury border regions after induction of myocardial infarction in adult rat hearts. They further examined effects of 5SM on cardiac regeneration over the course of 8 weeks after injury through fibrotic staining and echocardiography, finding that 5SM greatly reduced the final fibrotic area and improved cardiac performance throughout the recovery period. Impressively, 5SM treatment increased the function of injured hearts to levels comparable to that of the sham injury, indicating successful functional regeneration of the heart. 5SM appeared to increase cardiac function through non-hypertrophic methods, as cardiomyocyte cross-sectional area was comparable after injury in both treated and non-treated groups.With a robust regenerative effect in vivo, the mechanisms of exactly how 5SM induced cardiomyocyte proliferation required further investigation. Du et al. performed gene expression and chromatin landscape analysis on neonatal rat cardiomyocytes after 5SM treatment. They observed that 5SM-treated cardiomyocytes showed an upregulation of many cell division-related processes such as DNA replication and chromosome separation through increased gene expression as well as chromatin accessibility, as expected from the observed increase in proliferation of treated cardiomyocytes. Interestingly, the 5SM treatment had no effect on well-studied cardiomyocyte proliferation pathways Hippo and pERK (Garbern & Lee, Du et al. discovered a cocktail of five small molecules that induces cardiomyocyte proliferation and striking functional improvement in vivo following myocardial infarction in adult rats. Their cocktail shows clinical promise in its ability to induce proliferation in primary human atrial cardiomyocytes and hiPSC-derived cardiomyocytes in vitro, and with its small molecule platform enabling easier translatability than other transgene or viral treatments that require genetic modification. In exploring the mechanism of how 5SM induces cardiomyocyte proliferation, Du et al. revealed a previously unknown lactate-induced mechanism for quiescent cardiomyocyte cell-cycle re-entry through LacRS2-mediate metabolic signaling changes. This new mechanism for small molecule-induced dedifferentiation and cardiomyocyte cell-cycle re-entry opens the door for research into pathways that may drive highly efficient adult mammalian cardiomyocyte proliferation and regeneration. In addition to these novel advancements, their study also raises several questions: Are all five small molecules necessary to promote heart regeneration? Do these chemicals induce new vasculature formation and modulate activation of non-cardiomyocyte populations such as immune cells and fibroblasts to support regenerative repair? Can this cocktail also improve heart function of larger mammals after ischemic injury? These exciting steps for further explanation will build upon the findings of Du et al. to progress towards the goal of regenerating the human heart.


N = 342) completed an assessment of anxiety vulnerability and performed the masked-target antisaccade task in an online assessment session. Greater levels of anxiety vulnerability predicted poorer performance on the task, consistent with findings observed from eye-movement methods and with cognitive theories of anxiety and attention processing. Results also revealed the task to have high internal reliability. Our findings indicate that the masked-target antisaccade task provides a psychometrically reliable, low-cost, mobile, and scalable assessment of anxiety-linked differences in attentional control.Contemporary cognitive theories of anxiety and attention processing propose that heightened levels of anxiety vulnerability are associated with a decreasing ability to inhibit the allocation of attention towards task-irrelevant information. Existing performance-based research has most often used eye-movement assessment variants of the antisaccade paradigm to demonstrate such effects. Critically, however, eye-movement assessment methods are limited by expense, the need for expert training in administration, and limited mobility and scalability. These barriers have likely led to researchers’ use of suboptimal methods of assessing the relationship between attentional control and anxiety vulnerability. The present study examined the capacity for a non-eye-movement-based variant of the antisaccade task, the masked-target antisaccade task (Guitton et al.,  Contemporary cognitive theories of anxiety and attention processing propose that heightened levels of anxiety vulnerability are associated with a decreased ability to inhibit the allocation of attention towards task-irrelevant information  = .95; Myles et al., At present, research focusing on the relationship between anxiety vulnerability and antisaccade performance has consistently assessed performance through the recording of eye movements. This approach provides researchers with the benefit of measuring the accuracy and latency of participants’ attentional movements across the duration of a trial. In addition, researchers have reported that eye-movement-based measures hold a high level of internal reliability (αr(Spearman-Brown) = .59; Basanovic et al., Alongside assessments using eye-movement recording, researchers have developed approaches that instead utilise manual response latencies to index attentional control. For example, researchers have presented a visual target in the location opposite the distractor stimulus and recorded the speed at which participants are able to discriminate the identity of the target via a manual key-press  before being masked. Thus, accurate discrimination of the target necessitates rapid attentional movement away from the initial distractor stimulus. The task indexes performance via target discrimination accuracy, with a greater number of accurate responses across trials reflecting greater attentional control. Notably, this task has been shown to be associated with other tasks that require inhibition of pre-potent responses and cognitive control. For example, Friedman and Miyake (r = .20 to .23 and r = .16 to .19 respectively), though it is notable that the sizes of these correlations also indicate the influence of unshared processes on measures from each task. In addition, Kane et al. . However, Roberts et al. (r(Spearman-Brown) = .77 to .87; Friedman & Miyake, Thus, the capacity for researchers to investigate the relationship between anxiety vulnerably and attentional control is presently impeded by the absence of accessible, scalable, and reliable performance-based assessment methods that have been demonstrated to be sensitive to anxiety-linked differences in attention control. One task that may help solve this problem was developed by Guitton et al. , labelled Miyake  and Miyad Miyake  observede et al.  and Unswe et al.  demonstrs et al.  found noCritically, no research to date has sought to directly investigate whether the masked-target antisaccade assessment task demonstrates sensitivity to anxiety-linked differences in attentional control. Thus, the aim of the present study was to determine whether the masked-target antisaccade assessment approach is sensitive to anxiety-linked differences in attentional control. The study recruited individuals to complete a questionnaire measure of anxiety vulnerability followed by a masked-target antisaccade assessment task. Analyses examined the association between anxiety vulnerability and performance on the task and the internal reliability of the task. It was predicted that if the task is sensitive to anxiety-linked differences in attentional control, then greater levels of anxiety vulnerability will be associated with poorer performance on the task.M = 20.75 years, SD = 4.79 years) participated in the study. Invitations to participate were made available to students through undergraduate participant pools at Curtin University (N = 104), the University of Western Australia (N = 77), and the University of Sydney (N = 116), and via social media through the University of Sussex (N = 45).Recruitment of participants to this study was conducted online as part of the Cognition and Emotion Research Collaboration Initiative (CERCI) with researchers in Australia and England. In total, 342 individuals , and informed participants of any incorrect responses during the inter-trial interval.Upon accepting an online invitation to participate in the study, participants accessed the study via an online link using their personal computer. All assessments were delivered via the Inquisit Web platform. Participants were first presented information on the requirements of the study and provided informed consent. Participants next provided demographic information before completing a set of questionnaire measures that included the DASS-21. Additional questionnaires were completed for separate research projects. Participants then completed the masked-target antisaccade assessment task, followed by additional cognitive assessments completed for separate research projects. The antisaccade assessment task was always delivered prior to delivery of other tasks, and was immediately preceded by detailed instructions on its requirements. The additional questionnaires and tasks did not include any other measure of attentional control, or any measure conceptually related to cognitive control. Upon conclusion of the cognitive tasks, participants received debriefing information. The duration of the entire study protocol was approximately 30 minutes.The need for a criterion that can differentiate between low levels of ability as compared to low task engagement or compliance is present in all tasks that use response accuracy as a dependent variable of interest. As such, a participant exclusion criterion was employed with the intention of excluding individuals whose low performance resulted from low task engagement or compliance, while retaining participants whose low performance reflected genuinely low ability. This criterion required participants to demonstrate correct responses on more than 40% of trials (36 correct responses) to be included in data analysis. Accuracy above this threshold holds less than 5% probability of occurring in the case of random responding on the task as per a binomial distribution, and so was considered an appropriate criterion for exclusionSeventy-seven participants demonstrated a proportion below this threshold range, 21–40%). Thus, subsequent statistical analysis was conducted on the remaining 265 participants. Descriptive statistics of demographic measures, DASS-Anxiety Scale scores, and the proportion of trials with correct responses on the antisaccade assessment task are present in Table –40%. Thur(Spearman-Brown) = .86, CI95%[.84–.88]. This indicated a high level of internal reliability for the measure.The internal reliability of participants’ responses on the masked-target antisaccade assessment task was computed using a multi-permutation split-half correlation approach, which computed correlations between the proportion of correct responses across 5000 randomly generated split-halves Parsons, . The resDASS-Anxiety Scale scores and the proportion of trials with correct responses on the task was computed. This revealed a significant association between the two measures, r(263) = −.15, p = .016, indicating that elevated levels of anxiety vulnerability were associated with a lower proportion of correct responses on the masked-target antisaccade assessment task.To determine the simple association between participants’ level of anxiety vulnerability and performance on the masked-target antisaccade assessment task, the correlation between proportion of trials with correct responses as the dependant variable and DASS-21 Anxiety Scale scores as the predictor variable. The results of the regression analysis are present in Table To determine whether participants’ level of anxiety vulnerability predicted performance on the masked-target antisaccade assessment task, a logistic regression model was computed. The regression model included The results revealed a significant effect of DASS-21 Anxiety Scale scores, such that greater DASS-21 Anxiety Scale scores predicted reduced performance on the antisaccade assessment task. Specifically, the results demonstrated that with every one-point increase in the score on the DASS-21 Anxiety Scale, the odds of a correct response were reduced by 1.8%. In addition, the model’s prediction of the proportion of correct responses for each possible score on the DASS-21 was computed. This revealed a decline in the proportion of trials with correct responses between individuals scoring 0 (predicted proportion = .68) and individuals scoring 21 (predicted proportion = .60) on the DASS-21 Anxiety Scale.Readers interested in the association between performance on the antisaccade assessment task and measures of depression or stress recorded from the DASS-21 are encouraged to explore the data available at the public repository.The aim of the present study was to determine whether the masked-target antisaccade assessment task is sensitive to anxiety-linked differences in attentional control and to assess the task’s internal reliability. The results revealed that greater levels of anxiety vulnerability predicted declining levels of performance on the task. This association is consistent with predictions made by contemporary theories of anxiety-linked differences in attentional processing  = −.15). Previous research examining the association between anxiety vulnerability and antisaccade performance using eye-tracking measures has demonstrated larger effect sizes  = .86). Though the observed level of internal reliability is lower than some levels reported for eye-movement measures recorded during the antisaccade task (r(Spearman-Brown) = .95; Myles et al., r(Spearman-Brown) = .59; Basanovic et al., The present study also revealed that the masked-target antisaccade task holds a high level of internal consistency in its measurement (r(263) = −.14, p = .025. Thus, the task may also hold benefits for researchers seeking to investigate the relationship between depression and antisaccade performance without employing eye-tracking. Future research could usefully examine the sensitivity and reliability of the task in demonstrating this association by replicating the design of the present study but with the aim of examining whether performance on the masked-target antisaccade task is associated with individual differences in depression vulnerability.In addition to literature concerning the relationship between attentional control and anxiety vulnerability, a significant body of work concerns the relationship between attentional control and depression vulnerability Snyder, . This reThough previous studies have demonstrated that performance on the masked-target antisaccade task is associated with other measures of cognitive control, supporting its validity as a measure of attention control (Friedman & Miyake, M = .96, SD = .04; Roberts et al., The present study delivered the same design as has been demonstrated to be associated with performance on other tasks believed to load on the construct of attentional/cognitive inhibition control (e.g. Miyake et al., Lastly, researchers may wish to note implications arising from the relatively large number of participants whose low task performance resulted in their exclusion from analysis in the present study. One implication derives from the fact that the present study recruited a relatively young and educated sample, which suggests that greater numbers of participants may be excluded if the same exclusion criteria are adopted amongst participant samples for whom attentional control ability is lower. Additionally, researchers will need to account for the exclusion rate when determining the number of participants to be recruited in their own studies, particularly when studies are conducted in contexts that permit low engagement or compliance, such as online. Changes to study design may permit more specific criteria that reduce exclusion rates. For example, prolonging the presentation duration of the target stimulus may result in a greater number of participants who are able to achieve a level of performance sufficient to avoid exclusion. Alternatively, including measures that directly assess task engagement and compliance may allow specific identification of participants to be excluded from analyses. Researchers adopting the masked-target antisaccade task may wish to consider whether such approaches may benefit their study.For the moment, however, the present findings indicate that the masked-target antisaccade task provides a psychometrically reliable, low-cost, mobile, and scalable assessment of anxiety-linked differences in attentional control. It is hoped that the findings will aid researchers by affording a means to overcome existing barriers to robustly investigating anxiety-linked individual differences in attentional control, and so will facilitate research into this relationship into the future.


Rare disease clinical trials are constrained to small sample sizes and may lack placebo-control, leading to challenges in drug development. This paper proposes a Bayesian model-based framework for early go/no-go decision making in rare disease drug development, using Duchenne muscular dystrophy (DMD) as an example. Early go/no-go decisions were based on projections of long-term functional outcomes from a Bayesian model-based analysis of short-term trial data informed by prior knowledge based on 6MWT natural history literature data in DMD patients. Frequentist hypothesis tests were also applied as a reference analysis method. A number of combinations of hypothetical trial designs, drug effects and cohort comparison methods were assessed. The proposed Bayesian model-based framework was superior to the frequentist method for making go/no-go decisions across all trial designs and cohort comparison methods in DMD. The average decision accuracy rates across all trial designs for the Bayesian and frequentist analysis methods were 45.8 and 8.98%, respectively. A decision accuracy rate of at least 50% was achieved for 42 and 7% of the trial designs under the Bayesian and frequentist analysis methods, respectively. The frequentist method was limited to the short-term trial data only, while the Bayesian methods were informed with both the short-term data and prior information. The specific results of the DMD case study were limited due to incomplete specification of individual-specific covariates in the natural history literature data and should be reevaluated using a full natural history dataset. These limitations aside, the framework presented provides a proof of concept for the utility of Bayesian model-based methods for decision making in rare disease trials. Available treatments exist for only 5% of rare diseases, leaving hundreds of millions of affected patients worldwide without treatment . Though Typical drug development programs for common diseases include a Phase 2 proof-of-concept clinical trial to gain a preliminary understanding of potential clinical efficacy before investing in larger and more complex dose-ranging and confirmatory clinical trials. While the same objective is relevant to rare disease drug development, performing multiple, sequential trials is often not feasible. In many cases, only two trials are conducted for a rare disease: a combined Phase 1/2 trial to learn about efficacy and safety, and a combined Phase 2/3 trial to confirm efficacy. The trials are typically small and poorly powered for a clinical outcome endpoint and dose ranging trials are often limited to the objectives of safety, tolerability, and pharmacokinetics. A central issue with drug approvals in rare diseases is the limited amount of evidence collected in these small clinical trials.Despite these challenges, the regulatory standards for approval of rare disease drugs are similar to those applied to investigational treatments of common diseases; that is the requirement of demonstrating “substantial evidence” of efficacy and safety for the intended indication from adequate and well-controlled investigations , 5.Early decision-making strategies for drug development aim to increase the efficiency of compound selection for late stage development. Analyses of preliminary short-term studies are performed, yielding predictions of the probability of success in longer, larger scale clinical trials. Informed decisions to either continue (“go”) or terminate (“no-go”) development of the drug for the specific indication are made. Various statistical methods and decision criteria or stopping guidelines have been applied to go/no-go decisions –8.The Bayesian statistical paradigm is a formal approach to include information that has been learned and accumulated prior to performing a new experiment. Prior knowledge is combined with newly collected data, and inferences are based on posterior probabilities of outcomes or quantities of interest.When applied to drug development, Bayesian methods formally incorporate prior knowledge about the disease, drug, endpoints, or other factors with newly collected clinical trial data. Prior data may be borrowed from sources such as historical controls, disease consortia, patient registries, or previous trials. The totality of evidence is applied to robustly evaluate drug effects, bolstering statistical power. This is an appealing factor for rare disease drug development where limited evidence from small trials is a key challenge.Bayesian inferences may be posed in terms of posterior probability distributions of model parameters or other quantities of interest, and predictive probability distributions of future events. Using Bayesian methods for drug development yields inferences based on clinically meaningful quantities specific to the indication. The probabilities are clearly and directly interpreted to assess trial results. Inference based on probabilities of meaningful clinical outcomes is appealing compared to hypothesis tests based on arbitrary levels of statistical significance.Duchenne muscular dystrophy (DMD) is a genetic pediatric rare disease that has recently faced drug development challenges. The disease is characterized by a lack of endogenous functional dystrophin, which causes progressive muscle weakening and deterioration . The 6-mThe first approved drug for DMD was granted conditional accelerated approval in 2016 . The iniHypotheses based on other muscular dystrophies and animal models postulate that recovery of at least 10  or 20 1 percent This paper proposes a Bayesian model-based framework for early go/no-go decision making in rare disease drug development, using DMD as an example. Early go/no-go decisions are based on projections of long-term functional outcomes from a Bayesian model-based analysis of simulated short-term trial data informed by prior knowledge based on 6MWT natural history data in DMD patients. Posterior simulations provide predictions of long-term 6MWT distributions to inform early decision making in the context of a clinically relevant assessment time frame. A number of hypothetical trial designs and analysis methods are assessed. The overall goal of this paper is to illustrate an example of early decisions made from projections of long-term outcomes, informed by prior natural history data. The resulting framework could be applied to any rare disease drug development program.The methods for the model-based analysis followed a simulation-estimation-simulation archetype. A natural history model was augmented with a hypothetical drug effect model to use as a clinical trial simulation and estimation model in this work .First, replicates of short-term clinical trial data of the 6MWT were simulated from the natural history model. Data were simulated to represent the observed samples from a hypothetical short-term 6 month DMD trial .Second, the posterior probability distributions of model parameters for each trial population were estimated. The estimation was informed by prior knowledge about 6MWT natural history, along with the new data from the simulated short-term trials. Distributions of the population as well as individual parameter estimates were obtained for use in posterior simulations .Lastly, longer-term projections of the 6MWT at 12 months were made through posterior simulations. The simulations were performed conditional on the individual parameter estimates .The projected data at 12 months were analyzed under two different cohort comparison methods for decision-making: at the mean level or with individual case-matched comparisons. The short-term trial data were also analyzed using a typical frequentist method to serve as a comparator to the Bayesian approach.These methods were applied to assess trials of various designs and three different assumed drug effect levels. The detailed methods are described in the following sections.A Bayesian natural history model of the 6MWT in pediatric DMD patients was previously developed using full Markov chain Monte Carlo (MCMC) Bayesian methods . An indiIndividual-specific covariates were incompletely specified in the literature data , but a cA hypothetical drug effect model was developed to simulate a treatment effect on top of the 6MWT natural history trajectory. For the purpose of this paper, it was assumed that a placebo response was equal to natural history. Model structures were investigated through population mean deterministic simulations (mrgsolve v0.10.0 ) and calThe trial simulation model was constructed from the natural history model augmented with the hypothetical drug effect model .Posterior predictive distributions of quantities of interest were generated for each trial replicate, given random draws from the resulting trial estimation model joint posterior distribution. These involved longitudinal extrapolation of model predicted quantities to time points extending beyond observed trial data.The quantity of interest, the ΔΔ6MWT at 12 months, was derived from the posterior predictive distributions of the individual projections using two main cohort comparison methods: the mean treatment arm estimate, or from individual case-matching . For indDecision criteria were applied to each trial replicate for go/no-go decision-making. Under the Bayesian paradigm, a “go” decision was declared if the posterior predictive probability of reaching the MCID at 12 months was at least 80%, otherwise a decision of “no-go” was declared. The Bayesian model-based analysis methods were applied to all trial designs .Frequentist analyses were applied only when observed data for both test and reference cohorts were available at the 6 month time point. This included trials with randomization to both treatment and placebo arms, or single treatment arm studies with reference control groups based on external natural history data . Under tThe percentage of correct decisions under each trial design and cohort comparison method were summarized for the Bayesian and frequentist methods.LP) in the natural history model [The final hypothetical drug effect (DE) model was a logistic function on the latent process . There was no clear pattern of increased performance with increased sample size or increased drug effect .This paper presented an early decision-making framework for rare disease drug development. The framework was applied to hypothetical short-term DMD trials of varying designs to make go/no-go decisions about continuation to late stage trials. Decisions were informed by prior natural history combined with newly collected trial data, and based on long-term projections from Bayesian model-based methods. The probability of achieving the targeted demonstration of efficacy was determined for 20 replicates of each trial design. Frequentist tests were also applied to the 20 replicates of each trial design, determining the probability of a difference between the treatment and placebo cohort means. Performance across the 20 replicates was summarized. The proposed Bayesian model-based framework was superior to the frequentist method for making go/no-go decisions across all trial designs and analysis methods in DMD. The frequentist control method was limited to short-term trial data only, while the Bayesian methods were powered with both observed and prior information.As demonstrated, there were inconsistencies evident between the results using the observed external database versus model-based placebo control data. Performance was markedly improved when case-matched control subjects were obtained from the external database . The extInvestigations were performed to identify the possible source of the inconsistency between the observed external database and the model-simulated placebo control data. The results of a simulation-based evaluation of the natural history model indicated bias in model predictions that may have propagated into the model-simulated control data. Simulation-based evaluations of the 6MWT change from baseline (CFB) indicated positive bias in the tails of the model predicted CFB distributions . PositivThe model evaluation results on the CFB scale indicated that a predictor(s) to describe the relationship between baseline and post-baseline points may be missing. Though the natural history model was previously validated to predict the 6MWT, it had not been previously evaluated specifically on the CFB scale in the age 7–13 subset of patients . The exaDue to issues with model misspecification on the 6MWT CFB scale, inferences about optimal methods for DMD early go/no-go decisions should be viewed as preliminary. Results for the cases using model-simulated placebo controls may be subject to model bias, while those using observed external data controls are likely to be reliable. Decision-making performance was strong for the low and high drug effects when using the external database, and increased with sample size . At the The specific results of this DMD case study should be reevaluated using a full dataset complete with individual predictors. These limitations aside, the framework presented here provides a proof of concept for the utility of Bayesian model-based methods for decision making in rare disease trials.The small sample sizes, lack of standardized outcome endpoints, and limited clinical trial data inherent in rare diseases create a unique need for open science collaborations and pre-competitive data sharing. The results of the DMD example highlight the challenges of validating a model for its intended use without access to a complete individual level data set. Only five published DMD studies reported the 6MWT data at the individual level , 27–30 aS1 Appendix(CPP)Click here for additional data file.S2 Appendix(CTL)Click here for additional data file.


Health promotion efforts have largely failed to effectively support adolescent girls to meet public health guidelines for physical activity (PA). Engaging mothers in the promotion of PA for their daughters is an important strategy to facilitate behaviour change. This paper provides an overview of the development of the SOLE MATES programme - a novel mother-daughter intervention.This programme of research follows the MRC guidance for development and evaluating complex interventions . Two reviews were conducted to synthesise the evidence base on (1) mother-daughter PA interventions and (2) adolescent girls' perceptions of PA participation. The behaviour change wheel (BCW) framework was then used to design the components of an intervention to improve adolescent girls' PA . Finally, a single-arm feasibility trial was conducted to examine recruitment, data collection, acceptability, resources and participant responses.Our evidence reviews showed that only a limited number of interventions designed exclusively to target mothers and daughters have been conducted. In addition, programmes for adolescent girls should focus on alternative activities aside from the competitive team-based sports often offered.The BCW design process resulted in a group-based face-to-face intervention, involving six intervention functions  and 18 behaviour change techniques. The 6-week programme includes weekly educational and practical group sessions plus home tasks and the provision of participant resources. In addition to encouraging participants to walk regularly, the programme also aims to empower mothers to be role models for their daughters positive health behaviour.Participants in the feasibility study were mothers (n = 27) with daughters (n = 31) aged 12-16 years. Eligibility rates were 93.4%, and baseline activity levels were low. Programme content, measures and facilitators were acceptable. Daily steps increased in mothers  and daughters .We demonstrate the value of formative research in the intervention development process. We show that it is feasible to increase the PA levels of teenage girls through an inter-generational multi-component PA programme. The SOLE MATES programme should now be examined for effectiveness using a RCT. If successful the scale-up and sustainability of the programme should be explored.


The consideration of regional analgesia (RA) in below-knee surgeries is always a controversial topic due to the fear of masking symptoms of developing compartment syndrome (CS) in the postoperative period. Compartment syndrome (CS) has been found frequently in below-knee surgeries, particularly among tibial diaphyseal fractures. Like any other surgery, below-knee surgeries have significant postoperative pain that requires effective postoperative analgesia protocol. The analgesia quality makes a big difference when compared with or without RA. Also, the presence or absence of RA cannot prevent or promote the development of CS. Therefore, patients should not be deprived of their right to remain pain-free in the postoperative period by compromising the analgesia protocol.The pain out of proportion to the surgery or injury is a typical symptom of developing CS, which can cause increased analgesic demands postoperatively. Timely diagnosis and treatment of CS require vigilant postoperative monitoring of the warning signs by trained staff. Avoiding RA for fear of presumed masking of symptoms and delaying CS diagnosis may not be a solution instead of choosing an appropriate RA with regular postoperative monitoring for such warning symptoms. The high-volume proximal adductor canal (Hi-PAC) block has been described as a procedure-specific and motor-sparing RA technique appropriate for below-knee surgeries.In this prospective study, we evaluated the analgesic efficacy of the Hi-PAC block in below-knee surgeries. We also observed the effect of the Hi-PAC block, due to proximal and distal drug distribution, on masking the symptoms of the developing CS during postoperative monitoring.We found the Hi-PAC block to be a safer and more effective RA alternative for below-knee surgeries with an added motor-sparing benefit that facilitated early mobility and discharge. Its property of not interfering with postoperative surveillance to detect the symptoms of CS and intervene in time helps deal with the anxiety of CS in below-knee surgeries. Perioperative pain management for patients undergoing below-knee surgeries is challenging due to the concerns about the postoperative development of acute compartment syndrome (ACS). ACS is a true orthopedic/traumatic/surgical emergency that can lead to ischemia and eventual necrosis if left untreated, resulting in significant morbidity and mortality. The incidence of ACS is 1%-10% of all leg fractures, of which 75% of cases are associated with long bone fractures , followed by distal radial fractures (18%) . It can Fear or anxiety of ACS deprives patients of the optimal analgesic options and exposes them to severe postoperative pain, resulting in an unsatisfactory hospital stay. Dependency on systemic analgesics alone often fails to meet escalating postoperative demands resulting in inadequate analgesia or oligoanalgesia. A comprehensive team approach is required to manage such a preventable and treatable situation. It requires identifying high-risk patients or surgeries prone to developing ACS, providing the most suitable analgesic regimen, and periodic vigilant monitoring of the signs and symptoms of impending compartment syndrome (CS) postoperatively by trained personnel -11.The application of regional analgesia/anesthesia (RA) in below-knee surgery is contentious due to the belief that it can mask ACS symptoms and put the patient at an unacceptably high risk of serious morbidity. However, evidence for such an assumption is lacking. We believe that RA neither masks the clinical symptoms of impending CS nor prevents ACS development. The development of ACS can be inevitable under favorable circumstances regardless of the presence or absence of RA. Therefore, the mere fear of preventable and treatable conditions such as ACS should not deprive patients of their right to remain pain-free with effective and complete postoperative pain management.An ideal RA technique for below-knee surgeries should provide effective analgesia without masking the symptoms of the developing CS and facilitate early mobilization and discharge. The high-volume proximal adductor canal (Hi-PAC) block is one such suitable RA technique described for below-knee surgeries -14. In oWe aimed to observe the analgesic efficacy of the Hi-PAC block along with its technical ease of administration, the clinical effect due to drug distribution pattern, and possible interference during daily postoperative evaluations to detect the symptoms of CS in patients included in this prospective study. We hypothesized that the Hi-PAC block would provide the desired procedure-specific and motor-sparing postoperative analgesia without masking the symptoms of the impending CS. We propose a new paradigm and an alternative RA technique to ensure safer and more efficient postoperative analgesia in below-knee surgeries.This prospective study included 15 patients of either sex with the American Society of Anesthesiologists (ASA) grades I and II who underwent lower extremity orthopedic surgeries below the knee joint under neuraxial anesthesia. We conducted this study from September 2021 to October 2021 with our hospital institutional review board (IRB) approval (reference number IRB/GH/Anaesthesia/008/2021/004). All study patients provided informed consent for anonymous data recording and sharing concerning this study.Patient preparationPreoperatively, all patients were premedicated with intravenous pantoprazole 40 mg, ramosetron 0.3 mg, and midazolam 2 mg. The proposed surgery was performed under neuraxial blockade, either spinal or combined spinal-epidural under tourniquet control. Intraoperatively, paracetamol 1 gm, ketorolac 30 mg, and dexamethasone 8 mg were administered intravenously as MMA protocol. The remainder of the intraoperative course of all patients was uneventful, without any need for change in anesthesia or analgesia protocol.Postoperatively, all patients were monitored in the recovery room and periodically assessed for the recovery of motor movements. In possible cases, preprocedural scans of the femoral nerve (FN) and popliteal SCN were performed to compare sonoanatomy before and after the block. After confirming motor recovery (active toe movements) prior to sensory , the Hi-PAC block was administered using 40 mL of local anesthetic (LA) solution (0.1% ropivacaine + dexamethasone 8 mg).Ultrasound-guided Hi-PAC blockA high-frequency linear ultrasound probe  was held transversely over the midthigh with the patient lying supine Figure . InitialThirty minutes after the Hi-PAC block, all patients’ toe movements were reevaluated. They were monitored in the recovery room till complete regression of spinal level and attaining discharge criteria. A postoperative MMA protocol was followed: oral paracetamol 1 gm four times a day, aceclofenac 100 mg twice a day, and pregabalin 75 mg at bedtime. Postoperative pain scores were recorded before and after the block and periodically for up to 24 hours using a visual analog scale (VAS) of 0-10 (0 = no pain and 10 = worst pain imaginable). Focused postoperative evaluations to screen the signs and symptoms of ACS were performed daily till the discharge of the patient. All patients were discharged on the fifth postoperative day with a mean pain score of 2/10 on VAS without any requirement of rescue analgesia or opioids.Primary and secondary outcomesThe primary outcome of this study was to determine the analgesic efficacy of the Hi-PAC block in providing postoperative analgesia for below-knee surgeries. The secondary outcomes included determining the duration to administer the block, determining the extent of the proximal drug distribution to check the involvement of additional neural components , confirming distal drug distribution around the SCN in the popliteal fossa, determining the distance of the drug spread around SCN from the popliteal crease, and calculating the total duration of the analgesia.Outcome measurementThe measured outcomes included the demographics of the patients, type of neuraxial anesthesia, duration of surgery, vital parameters, time to regain toe movement, time to administer block, proximal and distal drug distribution after block, pain scores (at rest and after squeezing leg muscles) at regular intervals for the first 24 hours, total analgesic duration, presence of any signs of compartment syndrome and complications till discharge.Data were encoded and recorded in an MS Excel spreadsheet program . Statistical analysis was performed using SPSS version 23 . Descriptive statistics were generated using means/standard deviations (SD) for continuous variables and frequencies and percentages for categorical variables Table . Data weWe found no significant change in vital parameters before and after the Hi-PAC block Figure . The meaThe mean time to regain toe movements after the neuraxial block was 293.33 ± 75.96 minutes. The mean time to administer the Hi-PAC block was 5.13 ± 1.35 minutes. Post-block scanning distally into the popliteal region confirmed drug spread around the popliteal SCN in 11 patients with a mean distance from the popliteal crease of 8.467 ± 4.51 cm. However, due to an above-knee slab/cast, distal scanning could not be performed in three out of 15 patients. Post-block scanning proximally into the distal femoral triangle revealed drug spread around SN in 15 (100%) and nerve to vastus medialis (NVM) in 14 (93.3%) patients. However, none of the patients had drug distribution around the FN in proximal FT. The total duration of analgesia in most of the patients (12 out of 15) was >24 hours  with motor-sparing advantage for sufficient duration (>24 hours) with the Hi-PAC block in below-knee surgeries. It helped reduce the need for rescue analgesics and subsequent opioid consumption postoperatively. Incorporating this novel RA technique into the postoperative pain management strategy resulted in increased patient compliance and satisfaction. Before deciding on an appropriate target-specific RA strategy, functional anatomy should always be considered. Hence, we followed the identify-select-combine approach : identifThe innervation of the leg below the knee is not as complex as that of the knee joint. It involves the major contribution from the SCN and a minor contribution from the SN  . The sinThe pain caused by the impending CS is fundamentally disproportionate to the injury or surgery. It can be considered an earlier marker of ACS than the classic “six Ps”  . Such a In our study, such excruciating pain out of proportion to the surgical dissection provided timely warning signals indicating the development of increased compartment pressure. Thus, despite a well-functioning regional block, such ACS-pro conditions were promptly diagnosed and addressed simultaneously. This situation led us to recognize the importance of postoperative monitoring of the developing CS, particularly in high-risk patients/surgeries, without compromising effective postoperative analgesia. Therefore, regular postoperative monitoring of the clinical signs of ACS by trained personnel should be mandatory in below-knee surgeries. Selective sensory RA techniques with low concentrated LA are preferred to facilitate such monitoring. However, such postoperative monitoring should not depend on whether the RA technique is included or excluded in the MMA regimen.In addition to postoperative monitoring, preoperative patient preparation and identification of possible risk factors are essential. The timing of surgery also plays an important role in preventing the development of postoperative ACS. Our surgical team thoroughly evaluated all study patients before posting them for surgery. Factors that caused the initial postponement of the surgery included significant edema over the affected area, blistering, the absence of skin wrinkling, or the inability to fold the skin over the affected area. These visual findings suggested increased compartment pressure due to injury and edema formation, which required preoperative monitoring in order to assess the further rise in compartment pressure or the need for emergency fasciotomy. Therefore, thorough preoperative and postoperative evaluations with the early suspicion of the disease help invoke an immediate response and prevent the future possibility of ACS .The use of RA in below-knee surgeries always creates a “to give or not to give” dilemma that supports both sides of the coin Figure . It may Every patient has the right to receive adequate, effective, and complete analgesia. As pain specialists, we also have a responsibility to keep our patients pain-free by selecting the most appropriate and safest analgesic protocol that must include RA as an essential ingredient. Incorporating the RA technique as an adjunct to MMA in any surgery has been proven multiple times to significantly reduce analgesic/opioid consumption and ultimately improve patient satisfaction by promoting enhanced recovery, early mobilization, and early discharge -28. SuchThis study was conducted as a pilot project for future comparative studies. The strengths of this study include recording the analgesic efficacy and motor-sparing effect of the Hi-PAC block for the first 24 hours, along with subsequent vigilant monitoring of the signs and symptoms of the developing compartment syndrome until discharge of all patients. The limitations include small sample size, monocentric nature, lack of a control group, and scope for various biases (selection and observation).In conclusion, the Hi-PAC block can provide effective postoperative analgesia without compromising the motor strength of the leg muscles and without masking the clinical symptoms of ACS during the periodic assessment of the patient. We believe that the Hi-PAC block can be an appropriate RA option to deal with ACS concerns/fear (ACS anxiety) associated with below-knee surgeries. Apart from all clinical advantages of the Hi-PAC block, it is a relatively easier block to learn (simple identification landmarks), administer , overcome difficulties such as the above-knee cast, and teach to trainee regional anesthetists. This novel RA technique needs to be further explored with prospective multicenter clinical trials of larger sample sizes to substantiate the results better. In addition, it requires radiographic or cadaver dye studies to correlate clinical outcomes with neural component involvement.


Encephalitis is a serious disease of the brain characterized by prodromal and specific neurological symptoms. HIV infections offer opportunistic viruses, such as Varicella-zoster virus (VZV), the chance to cause encephalitis in patients. There is a lack of information on the genetic diversity of VZV in Ghana and other parts of Africa which requires sequencing and characterization studies to address. The active evolution of HIV-1 in West Africa also requires continuous surveillance for the emergence of new genetic forms.VZV was detected in the CSF sample of an 11-year-old patient presenting with symptoms of encephalitis by real-time PCR diagnostics. To identify possible unknown aetiological pathogens, next-generation sequencing was performed, and revealed an HIV-1 co-infection.gag, pol, vif, env and nef regions and a near-complete VZV genome were analyzed by Bayesian inference, and phylogenetic trees were generated. The VZV sequence belongs to clade 5 and the HIV-1 sequence is a member of the CRF02_AG predominant circulating recombinant form in Ghana.Alignments of concatenated HIV-1 genome fragments in the Diagnostic tests for CSF HIV would be useful where possible in patients presenting with encephalitis due to VZV and other opportunistic viruses in Kumasi to shed light on the role of HIV in encephalitis cases in Ghana. This report reaffirms the role of the CRF02_AG circulating recombinant form in HIV infections in Ghana and also gives a preliminary genetic characterization of VZV in Kumasi, Ghana.The online version contains supplementary material available at 10.1186/s12985-022-01854-7. Encephalitis is a serious disease of the brain characterized by prodromal and specific neurological symptoms . Among tRecombinant HIV subtypes that are found in three or more epidemiologically unlinked individuals are referred to as circulating recombinant forms (CRFs). These CRFs exhibit varied patterns of geographic prevalence . DiffereVZV primarily causes chickenpox, and the latent virus can be reactivated under certain conditions, causing shingles , and is Infection with HIV increases the risk of developing reactivation of VZV infection with accompanying neurological complications as a result of subclinical movement of the virus into the central nervous system (CNS) . DespiteAlthough the main HIV-1 CRF in Ghana appears to be CRF02_AG, there are a plethora of other CRFs and unique recombinant forms (URFs) in the country  and we sHere we present the case of a co-detection of HIV-1 and VZV in a CSF sample obtained as part of routine care of a patient presenting with symptoms of encephalitis by real-time PCR diagnostics and subsequent next generation sequencing to determine unknown aetiological pathogens in encephalitic patients.An 11-year-old male presented to the emergency unit of the Komfo Anokye Teaching Hospital in Kumasi, Ghana, with a 3-day history of fever, chills, general malaise and progressively increasing drowsiness. Two days prior to hospital presentation, the mother had initiated treatment with artemether/lumefantrine for suspected malaria, but his condition did not improve. Initial evaluation showed a febrile patient (temperature 38.4 °C), who was not pale or icteric. He was not dehydrated, and the Glasgow coma score (GCS) was 13/15. The neck was supple and Kernig’s sign was negative. Rapid diagnostic test (RDT) for malaria was negative. An initial diagnosis of partially treated malaria with differentials of encephalitis/ meninigo-encephalitis or septicaemia was made. Appropriate samples including CSF were taken for routine biochemical and microbiological laboratory analysis. Results are shown in Table https://www.geneious.com). For classification of the VZV sequence obtained, available complete genomes of VZV on NCBI as of February, 2020 were downloaded and duplicates removed. The sequences were then aligned using the MAFFT algorithm available online at https://mafft.cbrc.jp/alignment/server/. All gaps within the alignment were removed using GapStreeze program v2.1.0 also available online at https://www.hiv.lanl.gov/content/sequence/GAPSTREEZE/gap.htmla to yield a final sequence alignment comprising 236 sequences with 119,892 sites of the genome available. Phylogenetic analysis was done by Bayesian inference using the MrBayes [Presence of VZV DNA was confirmed by real-time PCR testing using a Herpesvirus Multiplex PCR kit  and the LightCycler Multiplex DNA Virus Master , which yielded a cycle threshold (Ct) value of 24.35. A high-throughput sequencing (HTS) approach for whole genome sequencing was done using the KAPA RNA Hyper Prep Kit  for library preparation and the 150-cycle NextSeq reagent v3 cartridge  according to manufacturer’s instructions. Paired reads from the HTS run were assembled against a reference sequence from GenBank using Geneious prime 2019 , MaxChi (p = 0.001) and Chimaera (P = 0.0121) methods. There was no major parent identified for this recombination event and may suggest this sequence to be part of a recombinant lineage within the clade with an unknown ancient common ancestor.A co-infection with HIV was detected after HTS testing of the VZV positive CSF sample and was determined to be an HIV-1 virus by BLAST analysis. A near-complete genome of VZV which was 123,745 base pairs in length was obtained. The sequence was found to be most closely related to another sequence from Nigeria (GenBank Accession: KP771924) with a pairwise sequence identity of 99.99%. The sequence was submitted to GenBank and assigned accession number OL311042. Phylogenetic analysis showed the sequence to belong to clade 5 which is predominant in Africa  and as low as 77.1% in the envelope glycoprotein gene region . The phylogenetic analysis of the concatenated alignments however found the sequence to cluster with a CRF02_AG circulating recombinant form from Nigeria  and the Accurate diagnosis of CNS infections is essential for timely treatment and improved chances of survival. However, many obstacles hinder accurate diagnoses particularly in resource-limited settings where HIV is also endemic, chief among them the limited availability of laboratory diagnostic tests as well as treatments . In partIn settings where opportunistic CNS infections are detected especially in HIV endemic regions, screening for HIV in CSF may be useful. Without accurate diagnoses in the event of co-infection, challenges in treatment occur such as targeted elimination of the detected aetiological agent without consideration of the underlying HIV infection, leading to a poor prognosis. Even in the event of a known prior history of HIV infection and ART treatment, lack of CSF detection as an indicator of compartmentalization and resistance to therapy may hinder considerations for treatment options .During HIV infection, analysis of CSF has been found to be useful for the detection of opportunistic infections like VZV and other co-infections as well as the quantification of HIV viral load in CSF as an indicator for treatment failure and CNS compartmentalization . HoweverThe VZV sequence obtained in this report unsurprisingly clustered with other clade 5 sequences in line with the predominance of this clade in the African region . A studyShared recombination events within subsets of sequences within clades as seen in this report may suggest such lineages descended from recombinant parents as suggested by Norbet et al. who assumed this to be the case for intraclade recombination crossovers . This maThe sequence identity of the various sequence fragments in this report hints at a complex recombination history of the detected HIV-1 virus although the sequence appears to belong to the predominant CRF02_AG circulating recombinant form. This does not obviate the need for continuous surveillance to monitor genetic changes that may affect laboratory diagnostics and treatment.The result of this report provides a useful preliminary genetic characterization of a VZV virus in Kumasi, Ghana and its co-infecting HIV-1 Virus in an encephalitic patient.Additional file 1. Table S1. FASTA sequences of HIV-1 fragments used in phylogenetic analysis.


In late 2012, ivacaftor became available in the UK for people with cystic fibrosis (CF) aged 6 years and over with a G551D mutation. Long-term changes in treatment patterns have not previously been reported. We investigated long-term treatment patterns in people with CF with a G551D mutation who took ivacaftor and compared these with non-ivacaftor-treated cohorts using the UK Cystic Fibrosis Registry.Using 2007-2018 data we compared treatment patterns between four cohorts: 1: ivacaftor-treated; 2: ivacaftor era (2013-2018), ineligible genotype (no G551D mutation); 3: pre-ivacaftor era (2007-2012), eligible genotype (G551D mutation); 4: pre-ivacaftor era, ineligible genotype. Treatments included: inhaled antibiotics, dornase alfa, hypertonic saline, chronic oral antibiotics and supplementary feeding.Up to 2012 the percentages of people taking each treatment were similar between the two cohorts defined by genotype and tended to increase by year with a similar slope. Once ivacaftor was introduced, the use of other treatments tended to decrease or remain stable by year for the ivacaftor-treated cohort, whereas it remained stable or increased in the non-ivacaftor-treated cohort. This led to differences in treatment use between the two cohorts in the ivacaftor-era, which became more marked over time.We have shown a clear divergence in treatment patterns since the introduction of ivacaftor in a number of key treatments widely used in CF. Further research is needed to investigate whether the differences in treatment patterns are associated with changes in health outcomes. Phase III randomized controlled trials have found evidence that treatment with ivacaftor is associated with significant improvement in clinical outcomes including FEVmutation . IvacaftTreatment burden is an important factor in the quality of life of people with CF and identifying ways to reduce treatment burden is a top research priority for the CF community ,8. The e1%, age, and sex.We hypothesised that the introduction of ivacaftor would lead to changes in the long-term use of other key treatments in CF and aimed to investigate this in a large observational dataset. In this study we use UK CF Registry data to describe treatment use up to 6 years after initiating ivacaftor in individuals with a G551D mutation. The documentation of all chronic treatments in the registry permits an opportunity to evaluate these in detail. Treatments considered are inhaled antibiotics, chronic oral antibiotics, dornase alfa, hypertonic saline and supplementary feeding.  To appropriately investigate associations between ivacaftor and other long-term treatment use, methodology should also take account temporal changes in treatment use in the wider CF population. We therefore compare treatment patterns in ivacaftor-treated individuals with patterns in individuals in the same time period but not receiving ivacaftor due to their genotype. We also compare treatment patterns over time in similar cohorts defined by genotype, but observed in the time period before ivacaftor became available. The clinical characteristics of the cohort defined by genotype and time period are summarised, and we investigate whether any differences in treatment patterns between groups differs between FEV22.1We used data from the UK Cystic Fibrosis Registry, a national database sponsored and managed by the Cystic Fibrosis Trust. The registry was established in 1995 and records demographic data and annual review data on clinical measurements and treatment use, on nearly all people with CF in the UK Ivacaftor was introduced in the UK in 2013. For this study we used registry data from 2007-2018, giving six years before ivacaftor was introduced (pre-ivacaftor era: 2007-2012) and six years after (ivacaftor era: 2013-2018) to compare longitudinal patterns of treatment use in the pre-ivacaftor and ivacaftor eras. The following treatments were considered: inhaled antibiotics, chronic oral antibiotics, dornase alfa, hypertonic saline and supplementary feeding. For chronic oral antibiotics we considered all types combined, and also azithromycin and flucloxacillin separately due to the different clinical indications for these being prescribed for long-term use. Supplementary feeding was considered separately according to whether it was oral or by gastrostomy. Use of ivacaftor and each other treatment (yes/no) over the past year is available for each annual review recorded in the registry. Dates of starting and stopping ivacaftor were also available and were used to verify ivacaftor use for all individuals and identify individuals who stopped ivacaftor during the follow-up period.1% predicted  both in ivacaftor-treated individuals (who started using ivacaftor in the ivacaftor era) and in individuals who were not eligible for ivacaftor due to their genotype. This enables an investigation of whether any changes in treatment patterns seen in the ivacaftor users in the ivacaftor era could be due in part to general changes over time in treatment use.Ivacaftor was first licenced in the UK for people aged 6 and older with a G551D mutation in late 2012 (England) and 2013 , and later licenced for individuals with other gating mutations (2015) or the R117H mutation (2018), and younger patients. We focus on individuals with a G551D mutation who began taking ivacaftor in 2012 or 2013; these patients form the ‘ivacaftor-treated’ cohort, and the majority (92.2%) initiated ivacaftor in 2013. We did not include people who started ivacaftor in later years because we are interested in patterns of other treatments as a function of the time since starting ivacaftor. For this study an ‘eligible genotype’ was defined as having at least one G551D mutation.We defined four cohorts of individuals: ivacaftor-treated (2013-2018) (IVA-ELIG); ivacaftor era (2013-2018), ineligible genotype (IVA-INELIG); pre-ivacaftor era (2007-2012), eligible genotype (PRE-IVA-ELIG); pre-ivacaftor era (2007-2012), ineligible genotype (PRE-IVA-INELIG).The ‘baseline year’ was defined as the year 2013 for cohorts IVA-ELIG and IVA-INELIG (ivacaftor era), and 2007 for cohorts PRE-IVA-ELIG and PRE-IVA-INELIG (pre-ivacaftor era). For all cohorts, we excluded children who were under 6 years old at baseline and people who received a transplant (from the year in which the transplant was recorded onwards). We excluded people from IVA-ELIG if they stopped treatment with ivacaftor (from the year they stopped onwards) and from IVA-INELIG if they started ivacaftor during a later year (from the year ivacaftor treatment initiated onwards), when it became available for individuals with non-G551D mutations. Many individuals appear in both IVA-ELIG and PRE-IVA-ELIG or in IVA-INELIG and PRE-IVA-INELIG as they have data recorded in the registry in both time periods.There is some missing data on use of chronic treatments and we used a pragmatic imputation approach to address this. Where a missing value appeared in a year between two non-missing values that were the same, we set the missing value to be the same as the two non-missing values. For example, if a person was missing data on use of a given treatment in 2014, but was recorded as taking this treatment in 2013 and 2015, we assumed they were also taking it in 2014. After this procedure, observations with remaining missing data were excluded for the year the data were missing. To assess the sensitivity of results to this imputation method, we repeated the analyses twice using different methods: all missing data were imputed as either 0 (indicating no treatment use) or 1 (indicating treatment use).1% and annual number of days on intravenous therapy (IV) ). For each cohort, we calculated the proportions of people taking each of the treatments of interest by year, and corresponding 95% confidence intervals. Results are presented graphically to illustrate changes in treatment use over time in the four groups. The analysis looking at proportions of users over time was repeated separately in males and females, in children and adults (using age at baseline year), and by FEV1% in the baseline year . Chi-squared tests were used to test for differences in treatment use in the eligible and ineligible genotype groups in the baseline year and in the final year in the pre-ivacaftor era and the ivacaftor era. Hypothesis tests were not conducted for all years to avoid issues with multiple testing. We also investigated whether the trend in the proportions of treatment use over time differs by genotype group, in the pre-ivacaftor era and the ivacaftor era, separately. This analysis used a group-level logistic regression of the proportions of treatment use on genotype group, time, and their interaction. A test of the null hypothesis that the interaction term is equal to zero corresponds to a test of whether there is a difference in the trend of proportions over time by genotype group. All analyses were conducted in R version 3.6.1.We summarised key characteristics of individuals in the four cohorts by year . This increased to 75.6 in 2015 and back down to 73.3 in 2018. For the remaining cohorts, the average FEV1% tended to decrease over time. The proportions of people in each category of total IV days were similar across cohorts in the baseline year, but trends over time differed. For example, the proportion of people with zero IV days increased over time in the ivacaftor-treated cohort, but decreased for the other three cohorts. The proportions with pancreatic insufficiency at baseline ranged between 86.6% (IVA-INELIG) and 91.2% (IVA-ELIG). In the ivacaftor-era, there were consistently higher proportions of people with pancreatic insufficiency in the ivacaftor-treated cohort, compared to the ineligible cohort.Average ages for the four cohorts ranged between 20.3 and 22.9 at baseline and increase by year. The average FEV1% in the baseline year, sex and age. Results are shown for inhaled antibiotics, dornase alfa and hypertonic saline solution. Further results are given in Supplementary Tables 2-8 and Supplementary Figures 2-4.1% subgroups. For inhaled antibiotics, dornase alfa and hypertonic saline, differences in treatment use between the two genotype groups at the end of the ivacaftor era are larger for people with high lung function (FEV1%>80), compared to those with moderate or low lung function. Lower proportion of patients prescribed dornase alfa and hypertonic saline were also noted in children, with the close correlation between age and FEV1% noted. The subgroup analyses are described further in the online supplementary data.In the pre-ivacaftor era treatment use is similar in both genotype groups across all three FEVWe found no evidence of a difference in the trend of proportions of treatment use over time between the two genotype groups in the pre-ivacaftor era (Supplementary Table 9). In the ivacaftor-era, there was a significant difference (at the 5% significance level) in the trend of proportions over time between genotype groups, for all treatments except flucloxacillin and oral supplementary feeding (Supplementary Table 9).Results were very similar between different missing data imputation methods, indicating that the observed trends were not sensitive to how missing data were handled (results not shown).41%>80). Our analysis represents the first detailed description of treatment patterns within the UK ivacaftor-treated population with a G551D mutation following its introduction into routine clinical care. Hubert et al. We have shown a clear divergence in treatment use over time between individuals treated with ivacaftor and those untreated due to their genotype for a number of long-term treatments widely used in CF, including dornase alfa, hypertonic saline and inhaled antibiotics. When comparing treatment patterns in the two genotype groups in the time period before the introduction of ivacaftor we saw few differences, suggesting that the differences in treatment use seen in the ivacaftor era are not explained by other differences between the two genotype groups. We found evidence for treatment differences between ivacaftor-treated and comparator groups for dornase alfa and hypertonic saline within two years of ivacaftor initiation. Differences in treatment use between the ivacaftor-treated and comparator group were most pronounced for children and for those with high lung function , rather than whether the patient has actually been taking that treatment on a regular basis or indeed at all. Adherence levels are unknown and it is possible that the changes in treatment patterns over time may in fact be underestimated. Lower proportions of people prescribed chronic treatments in the ivacaftor group may reflect treatment discontinuation in response to no longer considering a therapy necessary, or recognition by the clinical team  that the treatment is not being taken despite a clinical recommendation to do so. Treatment burden in CF is high ,13,14) a,14 a13,1NCT04378153) and CF STORM (EudraCT number 2020-005864-77), which aim to assess treatment simplification for mucoactive nebulised therapies in patients on elexacaftor-tezacaftor-ivacaftor. Understanding the association between change in treatment patterns and clinical outcomes is important to help interpret real-world effectiveness data on e.g. lung function outcomes of patients on CFTR modulators, particularly if there is any deviation from an anticipated degree of efficacy that may have been expected from the original phase III clinical trials. Multiple factors may contribute to this, but one possible explanation may be that treatment patterns for existing chronic therapies have not remained static. With the opportunity for significant potential benefits of highly effective modulators on long-term outcomes in people with CF, it is important that this is evaluated as a priority to help inform patients’ and clinical care team's decision making about long-term outcomes.The treatment differences we report within this observational data may be important in relation to longer-term clinical outcomes. It is of interest to investigate the impact of changes in use of other treatments on clinical outcomes in people taking ivacaftor, and to extend this when similar data become available from patients taking elexacaftor-tezacaftor-ivacaftor. Such investigations will complement the results that will be yielded from current or planned randomised controlled trials SIMPLIFY (ClinicalTrials.gov: In conclusion, we have shown that there are clear differences in treatment patterns as documented on the CF Registry over a 5 year period for those treated with ivacaftor for G551D mutation, compared to a contemporary cohort not using ivacaftor. The methodology employed to compare groups provides an opportunity to understand the association of these changes with longer-term clinical outcomes.Emily Granger: Methodology, Formal analysis, Visualization, Writing – original draft. Gwyneth Davies: Conceptualization, Methodology, Writing – original draft, Writing – review & editing, Supervision. Ruth H. Keogh: Conceptualization, Methodology, Writing – review & editing, Supervision, Funding acquisition.


Squatting exercises are commonly used in rehabilitation for knee joint disorders; in these exercises, control of knee extensor moment is important to enhance training effects and to avoid adverse effects. Ankle dorsiflexion and trunk flexion are widely used to reduce knee extensor moments during squatting, but the increased load on the low back is a concern. The purpose of this study was to determine whether the anterior–posterior (AP) center-of-pressure (COP) position and the AP-COP position in combination with ankle dorsiflexion and trunk flexion angles can predict the contribution of the knee extensor moment during double-leg squatting.Twenty-eight healthy individuals  performed three sets of five consecutive double-leg squats. Kinematics and kinetics were analyzed using a three-dimensional motion analysis system with force plates. Univariate and multivariate regression analyses were performed to predict the contribution of the knee extensor moment  from AP-COP position, ankle dorsiflexion, and trunk flexion.R2 = 0.168, P = 0.030). Multivariate analysis showed that the ankle dorsiflexion angle  and AP-COP position  predicted the knee extensor moment contribution . Additionally, the combination of trunk flexion  and AP-COP position  predicted the knee extensor moment contribution . The limb symmetry index of the knee extensor moment was significantly associated with that of the AP-COP position  but not with that of the ankle dorsiflexion angle (P = 0.057).The AP-COP position was a significant predictor of the knee extensor moment contribution (The AP-COP position can predict the contribution of the knee extensor moment and improve the prediction when combined with ankle dorsiflexion and trunk flexion. The present findings suggest that intervention focusing on the AP-COP position in combination with ankle dorsiflexion or trunk flexion would be useful to coordinate the contribution of the knee extensor moment during double-leg squatting. Squatting exercise is frequently and widely used to train the lower limb muscles in rehabilitation and conditioning . The desThe effects of ankle dorsiflexion and the resulting anterior knee position on the knee extensor moment during double-leg squatting, as well as the effects of trunk flexion, have been well studied –11. ReduA previous study showed that a more anterior center-of-pressure (COP) position was associated with a smaller contribution of the knee extensor moment relative to the hip and ankle extensor moments during double-leg squatting after anterior cruciate ligament reconstruction . The antIn addition, significant interlimb asymmetry in the knee extensor moments was reported even for healthy individuals . The limThe purpose of the present study was to determine whether the AP-COP position alone and in combination with ankle dorsiflexion and trunk flexion angles can predict the contribution of the knee extensor moment during double-leg squatting. In addition, the relationships between the AP-COP position and ankle dorsiflexion and trunk flexion were examined. The hypotheses were that adding the AP-COP position to ankle dorsiflexion and trunk flexion would improve prediction of the knee extensor moment and that the LSI of ankle dorsiflexion and the AP-COP position would predict the LSI of the knee extensor moment.α) and statistical power (1 − β) of 0.05 and 0.8, respectively, 27 participants were needed. Therefore, the present study enrolled 28 participants . Participants were excluded from this study if they reported pain during double-leg squatting, had any history of musculoskeletal injury within the prior 6 months, or had surgery of the lower extremities or the trunk. Written informed consent was obtained from each participant before participation. This study was approved by the Institutional Review Board of Faculty of Health Sciences, Hokkaido University .Based on previous studies , 11, 13,Participants warmed up using a stationary bicycle ergometer at a self-selected pace for five minutes. Then, retroreflective markers were placed on the iliac crest, anterior and posterior superior iliac spines , lateral thigh, medial and lateral femoral epicondyle, lateral shank, medial and lateral malleoli, second metatarsal head and base, fifth metatarsal head and heel. Following a static standing trial, participants performed three sets of five consecutive double-leg squats. They squatted down until their thighs were parallel to the floor and then stood upright . If theiA motion capture system  with seven high-speed digital cameras  and two synchronized force plates  were used for data recording. The sampling rates were set to 200 Hz for the marker trajectory data and 1000 Hz for the force plate data.Kinematic and kinetic analyses were performed using Visual3D . Marker trajectories and force plate data were low-pass filtered using a fourth-order, zero-lag Butterworth filter with a 12 Hz cutoff frequency , 5. The The middle three of the five consecutive squats were analyzed . The kneP < 0.05. These statistical analyses were performed using JMP Pro software .All data are presented as the mean and standard deviation (SD). Univariate regression analysis was conducted to confirm the linear relationship between the knee extensor moment contribution and the AP-COP position and ankle dorsiflexion and trunk flexion angles. In addition, the linear relationships between the AP-COP position, ankle dorsiflexion angle and trunk flexion angle were also examined. Then, multivariate regression analysis was performed to determine the predictive ability of AP-COP position independent of ankle dorsiflexion and trunk flexion angles. A regression model of ankle dorsiflexion with trunk flexion was also tested. Analysis was performed regarding the dominant side, nondominant side and LSI. A paired t test was also conducted to confirm differences in variables of interest between the dominant and nondominant sides. The statistical significance level was set at P < 0.05)     (Table P = 0.393–0.939).Univariate analysis showed that the AP-COP position was significantly negatively associated with the knee extensor moment contribution (05) Fig. a. The anR2 = 0.418, P < 0.001) but not by the LSI of the ankle dorsiflexion angle  .Significant interlimb differences were found for all interesting variables Table . The LSIThe present study revealed that the AP-COP position significantly predicted the knee extensor moment contribution during double-leg squatting in univariate analysis and multivariate analysis when combined with the ankle dorsiflexion and trunk flexion angle. In addition, the LSI of the AP-COP position was found to be the only predictor of the LSI of the knee extensor moment contribution. These findings support the a priori hypothesis.The AP-COP position was significantly negatively associated with the knee extensor moment contribution, while the ankle dorsiflexion angle was significantly positively associated with the knee extensor moment contribution; the trunk flexion angle was negatively associated. Furthermore, the addition of the AP-COP position to the ankle dorsiflexion and trunk flexion angle significantly improved the prediction of the knee extensor moment contribution. The ankle dorsiflexion angle explained approximately 50–56% of the variance in the knee extensor moment contribution, and the AP-COP position added 25–30% of the explanation. In the model combining the AP-COP position and trunk flexion, the trunk flexion angle explained approximately 36–43% of the variance in the knee extensor moment contribution, and the AP-COP position contributed another 11–17%. Moreover, the coefficient of determination of the model combining the AP-COP position and ankle dorsiflexion and trunk flexion angle was equal to or higher than that of the model combining the ankle dorsiflexion angle and trunk flexion angle, which has been widely used for the assessment of squatting , 11. TheAs shown in previous studies –11, the Furthermore, the AP-COP position predicted the knee extensor moment independently of the trunk flexion angle in the multivariate model, and there was no significant association between the AP-COP position and trunk flexion angle. These findings suggest that the AP-COP position may be modified without changing the trunk flexion angle and may be useful in combination with this angle to predict the knee extensor moment contribution. Trunk flexion motion is considered compensation for the posterior shift of the COP position during squatting with restriction of ankle dorsiflexion , 12. HowThe present study found significant interlimb differences in all interesting variables, including knee extensor moment contribution, ankle dorsiflexion and AP-COP position. However, the LSI of the AP-COP position was the only parameter that could be used for predicting the LSI of the knee extensor moment contribution. A previous study showed that the LSIs of the knee extensor moment were significantly predicted by the LSI of the AP-COP position for patients after anterior cruciate ligament reconstruction . The meaThe AP-COP position can predict the knee extensor moment contribution during double-leg squatting independent of the ankle dorsiflexion and trunk flexion angles. These findings suggest the possibility that the knee extensor moment can be coordinated by modifying the AP-COP position without strictly limiting ankle dorsiflexion or increasing trunk flexion, which are concerned about the increased load on the low back. Visual feedback regarding the AP-COP position requires only a force plate and may be useful for controlling knee extensor moment during double-leg squatting exercises. A recent study has shown that a difference in the AP-COP position of approximately 10% of foot length changed the knee extensor moment by 6% without difference in trunk flexion and ankle dorsiflexion , which sThe COP position should be guided anteriorly to reduce the knee extensor moment in order not to interfere with graft healing in the early postoperative period after anterior cruciate ligament reconstruction, while the COP position should be guided posteriorly to increase the knee extensor moment in the rehabilitation period to build the strength of the quadriceps. Furthermore, instruction in maintaining a symmetrical AP-COP position using visual feedback regarding the AP-COP position may help to reduce asymmetry of the knee extensor moments after anterior cruciate ligament reconstruction. Patients with knee extensor mechanism problems such as patellar tendinopathy or patellofemoral pain syndrome may also benefit from AP-COP position feedback help them control their knee extensor moment during double-leg squatting.There are some limitations of this study that should be acknowledged. First, this study examined double-leg squatting without a resistance weight. Therefore, squatting with a resistance weight may result in models that are different from those in the present study. Second, it is unclear whether intervention that focuses on the AP-COP position and ankle dorsiflexion reduces the knee extensor moment without changing trunk flexion. Additional studies should be performed to investigate the effects of instructions focusing on the AP-COP position combined with ankle dorsiflexion on knee extensor moment and hip and trunk biomechanics.The present study investigated whether the AP-COP position alone and in combination with ankle dorsiflexion and trunk flexion angles can predict the contribution of knee extensor moment during double-leg squatting. The results showed that AP-COP position was a predictor of the knee extensor moment contribution in univariate analysis and when combined with the ankle dorsiflexion angle and trunk flexion angle. On the other hand, the AP-COP position was not significantly associated with the ankle dorsiflexion or trunk flexion angle. Therefore, intervention focusing on the AP-COP position combined with the ankle dorsiflexion and trunk flexion angles would be useful to coordinate the contribution of the knee extensor moment during double-leg squatting. Furthermore, only the LSI of the AP-COP position was a predictor of the LSI of knee extensor moment contribution. Therefore, the feedback regarding interlimb difference in AP-COP position would be useful to modify the interlimb difference in knee extensor moment contribution.