NOTCH1 genetic variants in patients with tricuspid calcific aortic valve stenosis

BACKGROUND AND AIM OF THE STUDY: Calcific aortic valve stenosis (AS) affects 2-5% of the population aged > 65 years. Functional DNA variants at the NOTCH1 locus result in bicuspid aortic valve (BAV) and severe valve calcification. The contribution of these variants to AS in the population with tricuspid aortic valve (TAV) remains to be determined. METHODS: Fourteen genetic variants surrounding the NOTCH1 gene were genotyped, including rare mutations previously reported, and common polymorphisms. The study involved 457 French Canadian patients with severe tricuspid AS. Genotyping was carried out using the Illumina BeadXpress platform. Allele frequencies of common single nucleotide polymorphisms (SNPs) for patients with AS were compared to a shared control group of European ancestry (n = 3,294). In total, 88 ancestry-informative markers were used to correct for population stratification. RESULTS: The mutation R1107X, previously associated with AS and BAV, was identified in a relatively young patient (aged 58 years). The mutations R1279H and V2285I were detected in 18 and 14 heterozygotes, respectively. A common polymorphism (rs13290979) located in intron 2 was significantly associated with AS (p = 0.003), which remained significant after correction for multiple testing. However, this association was no longer significant after accounting for population stratification (p = 0.088). CONCLUSION: In this study, rare functional variants were found in the NOTCH1 gene in a French Canadian population of patients with severe tricuspid AS. This also suggests, for the first time, the presence of a common polymorphism in this gene conferring susceptibility to AS

Deleterious variants in DCHS1 are prevalent in sporadic cases of mitral valve prolapse

Background: A recent study identified DCHS1 as a causal gene for mitral valve prolapse. The goal of this study is to investigate the presence and frequency of known and novel variants in this gene in 100 asymptomatic patients with moderate to severe organic mitral regurgitation. Methods: DNA sequencing assays were developed for two previously identified functional missense variants, namely p.R2330C and p.R2513H, and all 21 exons of DCHS1. Pathogenicity of variants was evaluated in silico. Results: p.R2330C and p.R2513H were not identified in this cohort. Sequencing all coding regions revealed eight missense variants including six considered deleterious. This includes one novel variant (p.A2464P) and two rare variants (p.R2770Q and p.R2462Q). These variants are predicted to be deleterious with combined annotation-dependent depletion (CADD) scores greater than 25, which are in the same range as p.R2330C (CADD = 28.0) and p.R2513H (CADD = 24.3). More globally, 24 of 100 cases were carriers of at least one in silico-predicted deleterious missense variant in DCHS1, suggesting that this single gene may account for a substantial portion of cases. Conclusion: This study reveals an important contribution of germline variants in DCHS1 in unrelated patients with mitral valve prolapse and supports genetic testing of this gene to screen individuals at risk

Targeted exercises can improve biomechanical markers in individuals with knee osteoarthritis: A secondary analysis from a cluster randomized controlled trial

Background: It is not clear whether exercise therapy significantly improves knee biomechanics during gait in osteoarthritis (OA) patients. This study aimed to determine whether targeted exercises based on a knee kinesiography exam improve biomechanical markers (BMs) compared with conventional primary care (CPC) management. Methods: This was a secondary analysis of a cluster randomized controlled trial in which patients were assigned to one of three groups: (1) Control (CPC), (2) Exercise, and (3) Exercise&Education. Fourteen known BMs in knee OA patients were assessed. The primary outcome was the global evolution ratio (GER), which was calculated as the sum of improved BMs over the sum of deteriorated BMs 6 months after baseline assessment. GER scores were categorized with three different sets of cut-off values into clinical levels: (a) Deteriorated, (b) Stabilized, and (c) Improved. Ordinal logistic regressions were performed on the per-protocol population to determine whether there was a relationship between group assignment and GER levels. Results: Of the 221 eligible participants, 163 were included. Two different regression models showed that patients from Group 3 (Exercise&Education) were 2.5-times more likely to be in an upper GER level (i.e., Stabilized or Improved) than patients from the control group (both odds ratio (OR) > 2.46, Wald Χ2(1) ≥ 7.268, P ≤ 0.01). They also reported significantly more improvement in pain and function (Knee Injury and Osteoarthritis Outcome Score, both P ≤ 0.01). Conclusions: Results suggest that targeted exercises can improve biomechanical markers in knee OA patients compared with CPC treatment. Further studies are needed to confirm these findings and refine the biomechanical markers to address to maximize patients’ clinical outcomes

Impact of a personalized care approach on 3D gait impairments in knee osteoarthritis patients (a cluster randomized controlled trial)

Purpose: Knee osteoarthritis (OA) often leads to gait kinematic impairments. The knee kinesiography exam, measuring three-dimensional (3D) knee kinematics during gait on a treadmill, allows to objectively identify gait impairments (GIs) in order to provide recommendations for a personalized care approach (targeted home-based exercises, bracing, etc.) to correct these impairments. A clinical trial showed that this approach can lead to significant improvement in function and pain reduction after 6 months compared to a control group. The aim of this study was to assess the impact of this personalized care approach (PCA) on 3D mechanical GIs in knee OA patients compared to a control group. Methods: Primary care physicians in this cluster randomized controlled trial in the Province of Quebec (Canada) were asked to recruit patients with a clinical diagnosis of knee OA. Patients were included if 1) knee OA was the main cause of their knee pain, 2) they rated their worst pain in the past 7 days ≥ 4 on a 0-10 pain intensity scale, 3) they had a Kellgren-Lawrence grade ≥ 2 on radiographs. Eligible patients from a same primary care clinic were randomized to the same group: 1- a control group (usual care), 2- a group with the PCA, and 3- a group with the PCA + an educational program. In all of the three groups, primary care physicians managed their patients according to their individual needs, but only physicians from groups 2- and 3- had access to the recommendations for the PCA. These were treatment recommendations (e.g. bracing, specific activities, etc.) and tailored home exercises targeting the GIs identified with the knee kinesiography results. Patients from group 3- also had a one-hour educational session on knee OA self-management and two follow-up group meetings with a therapist (to answer their questions, regulate the nature and intensity of their exercises, etc.). For all patients, we assessed the presence of 14 known GIs in knee OA at baseline and 6-month follow-up (see Table 1). If a GI changed from “Present” at baseline to “Absent” at 6 months, we considered it as improved. If it changed from “Absent” to “Present”, it was considered deteriorated. In order to summarize all GIs’ evolution in a single outcome, we calculated for each patient a global evolution ratio (GER) corresponding to the ratio of the sum of improved GIs over the sum of deteriorated GIs. The GER status was defined as “DETERIORATION” (≤0.5), “STABILIZATION” (0.5<GER<1.5), or “IMPROVEMENT” (≥1.5). Chi-square tests were used to assess between-group differences on the GER status. Results: 221 patients from 55 clinics participated. There were 61.1% women, the mean age was 63 years (95%CI: 62;64), and the mean BMI was 29.5 kg/m2 (95%CI: 28.7;30.2). There were no differences between groups at baseline on sociodemographic characteristics and patients were equally distributed between the three groups (1-Control: N=71; 2-PCA: N=72; 3-PCA+Education: N=78). There was a significant difference between the three groups on the GER status (p=0.03). Post-hoc analysis showed that both groups who received the PCA significantly differed from the control group (both p<0.05). As shown in Figure 1, the proportion of patients with an improved GER was higher in both groups with the PCA (Group 1: 28.2% vs Group 2: 37.5% and Group 3: 38.5%), and the proportion of patients with a deteriorated GER was lower (Group 1: 50.7% vs Group 2: 26.4% and Group 3: 30.8%) compared to the control group. There was no significant difference between the two groups with the PCA (p=0.75). Conclusions: Results suggest that a personalized care approach including tailored treatment recommendations (e.g. exercises, orthoses, etc.) to correct GIs can have a positive impact on 3D knee kinematics during gait after 6 months. Patients from both groups who had access to this PCA showed significantly less deterioration, and more stabilization and improvement of their gait impairments compared to the control group. There was no difference between groups 2- and 3-, suggesting that this approach may have an effect on gait impairments even without an additional education program. The proposed global evolution ratio showed interesting results but further analyses are needed to specifically identify which GIs’ evolutions have the most impact on patient outcomes

Effective conservative care targeting mechanical markers as risk factors for knee osteoarthritis progression: a cluster randomized controlled trial

Purpose: Primary care physicians (PCPs) have underscored the lack of adequate assessment tools to guide therapies within current medical management (CMM) of knee osteoarthritis (KOA) patients. It is well recognized that joint mechanics are important risk factors in KOA progression and that kinematics information can be useful to assess causes of symptoms. Dynamic knee KinesioGraphy (KG-Knee) assessment can be performed by a trained therapist (physical therapist, kinesiologist, physical rehabilitation therapist) in a clinical setting to serve as an objective measurement tool to identify and measure evidence-based mechanical markers. The aim of this study was to determine the impact on clinical outcomes of adding a KG-Knee assessment and personalized treatment recommendations to CMM for KOA patients. Methods: This pragmatic, cluster randomized, controlled trial was carried out in primary care clinics (Montreal, Canada). Patients with a clinical diagnosis of KOA as identified by their PCP were selected for participation if 1) KOA was the main cause of their knee pain, 2) they rated their worst pain in the past 7 days ≥ 4 on a 0-10 pain intensity scale, 3) they had a Kellgren-Lawrence (KL) grade ≥ 2 on radiographs. They were excluded if they 1) were on a waiting list for total knee replacement, 2) suffered from rheumatoid arthritis or active cancer, 3) had met a specialist of KOA in the past or 4) were pregnant. Participants from a same clinic formed a cluster which was randomly assigned to one of 3 groups: 1- a control group with patients receiving CMM (Group 1-CMM), 2- an intervention group receiving CMM plus KG-Knee-based recommendations (Group 2-KG-Knee), and 3- an intervention group receiving CMM, KG-Knee-based recommendations, and a self-management education session plus two follow-up supervised meetings (Group 3-KG-Knee+Education). In the KG-Knee groups, three-dimensional knee kinematics at baseline were captured using the KneeKG™ system (Figure 1) during treadmill walking at a self-determined comfortable speed. Therapists also performed a standardized musculoskeletal assessment and combined their findings on these two assessments to establish KG-Knee-based recommendations. Those consist of treatment recommendations (e.g. orthoses, cardiovascular activities⋯) and a personalized home exercise program targeting the identified mechanical markers linked to KOA progression. Patients from Group 2 received them directly from their PCP. Patients from Group 3 met with the therapist for a one-hour education session on KOA self-management, received explanations on their exercises and two follow-up sessions to regulate the nature and intensity of their exercises. Primary outcomes were the scores on the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales and the overall score. Quadriceps strength (with a manual dynamometer) and the 30 seconds Chair Stand test (30sCST) were used as objective tests to assess function at baseline and 6 months after intervention. Patients global impression of change (PGIC) and satisfaction level in regards to their treatment were also collected at 6 months, as well as adherence in the KG-Knee groups (asking patients if they had followed the recommended exercises for at least 3 months). Linear Mixed models adjusting for the cluster design of the study were used. We assessed between-group differences at baseline on sociodemographic and clinical characteristics, and after 6 months adding TIME (baseline/6-month) to the models as a variable. If the time*group interaction on outcome scores between the three groups was statistically significant, post-hoc analyses were performed on delta scores. Chi-square tests were used to assess between-group differences on PGIC and satisfaction. Results: 894 patients from 87 clinics were contacted, 515 were randomized, and 449 (87.2%) completed the study. There were 66.4% women and the mean age was 63.6 years (95% confidence interval: 62.8;64.5). There were no differences between groups at baseline (Table 1). At 6-month follow-up, patients in both KG-Knee groups reported statistically significant improvement on the KOOS overall score (Group 2-KG-Knee: +5.5; Group 3-KG-Knee+Education: +5.0) compared to the control group (both p=0.02; Tables 2-3). They also reported statistically significant improvement in terms of symptoms, pain, and function during activities of daily living (KOOS: all p<0.05), as well as higher treatment satisfaction levels compared to Group 1-CMM (both p<0.001). Patients in Group 3-KG-Knee+Education had statistically significant improvement in both objective functional tests and showed a greater global impression of change in pain, function, and quality of life (all p<0.05). Adherence to the exercises was significantly higher in Group 3 (87%) than in Group 2 (56%). Conclusions: These results support the clinical added value of a Knee KinesioGraphy assessment to personalize conservative treatment strategies: symptoms and pain can be reduced, function and satisfaction can be improved. A maximum of three sessions including education and follow-up can reinforce adherence to PCPs recommendations and further improve outcomes. This study reinforces that assessing mechanical markers with a dynamic knee functional test can be useful to support treatment management of non-surgical KOA patients

Musculoskeletal and biomechanical characteristics are better associated with knee clinical condition than radiographic severity in osteoarthritis patients

Purpose: The diagnosis of knee osteoarthritis (OA) is typically well established with a clinical evaluation and confirmed with an X-Ray assessing the joint’ structural changes and disease progression. Guidelines also recommend taking into account mechanical factors (static and dynamic) to better understand knee function, since they may influence treatment outcomes. However, the relationship between clinical condition of the knee and biomechanical characteristics is not well known, including how such information stands compared to those from other conventional assessments, such as X-ray and physical assessment. The aim of this study is to evaluate the associations between the knee clinical condition assessed by patient-reported outcome measures and parameters from three different types of assessments, namely radiographic, musculoskeletal, and biomechanical assessment in OA patients. Methods: This cross-sectional study was conducted on patients with 1) knee pain ≥ 4/10 on a numeric rating scale in the past 7 days, 2) Kellgren-Lawrence (KL) radiographic OA severity grade higher than KL2, and 3) who were not on a waiting list for knee arthroplasty. Patients’ knee clinical condition was assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire that consists of five subscales: pain, symptoms, function in daily living (ADL), function in sport and recreation (Sport/Rec) and knee-related quality of life (QOL). Twenty musculoskeletal tests were performed by a therapist, including passive flexion and extension ranges of motion (ROM), muscle strength (10 tests assessing hip, knee, and ankle), flexibility (4 tests), swelling measured by the circumference difference between knees, effusion, balance, and functional 30-second chair stand tests (30s_CST). Finally, dynamic mechanical factors were measured during a knee kinesiography exam with the KneeKG™ system (Emovi Inc., QC, Canada) where 70 biomechanical parameters were extracted from 3D knee kinematic curves captured during gait (namely in flexion/extension, adduction/abduction, internal/external tibial rotation). KOOS associations with radiographic severity grades, musculoskeletal tests, and biomechanical parameters were assessed using a canonical correlation analysis (CCA). CCA is a statistical multivariate method for determining the association between two sets of variables measured on the same patients. This method is a multivariate extension of the bivariate approach, where the Pearson’s correlation coefficient r is calculated to quantify the association between two variables. CCA consists of maximizing the Pearson's coefficient between two sets of variables. This allows calculating two distinct types of correlations: the canonical correlations (i.e. ρ coefficients) which quantify the global association between the two sets, and the structural correlations (i.e. Corr coefficients) which estimate the association between a set as a whole and each variable of the other set. This method was used to calculate ρ and Corr coefficients between the KOOS set (i.e. the scores on its five subscales) and all three other data sets (i.e. KL grades, musculoskeletal tests, biomechanical parameters). These coefficients were calculated considering all participants and also sub-groups dividing men and women to assess the impact of sex. Results: 415 participants (251 women and 164 men) were included in this study. The mean (±standard deviation) age and body mass index were 63.3±9.2 years and 30.3±5.6 kg/m2 respectively. The radiographic severity grade was well distributed among patients in the cohort (mild_KL2_n=137, moderate_KL3_n=149, and severe_KL4_n=129). All ρ and Corr coefficients presented indicate a statistically significant correlation (all p0.30). When separating by sex, four of these five parameters were also among the most associated with KOOS in women (Table 2). The remaining parameter (passive flexion ROM) was the second most associated with KOOS for men (after the 30s_CST), followed by a biomechanical parameter (flexion angle ROM during loading) and two additional musculoskeletal parameters (i.e. ankle plantar flexion and hip extension strengths; Table 2). Among these best-associated parameters, the 30s_CST and the flexion angle ROM during loading were the only ones shared between men and women sub-groups. Notably, the radiographic severity grade was more associated with KOOS in men than in women (Corr=-0.261 vs -0.161 respectively). Conclusions: Results suggest that musculoskeletal and biomechanical characteristics are better associated with the patient clinical condition than radiographic severity for knee OA patients. Differences were observed between sexes, as women’s condition was more associated with biomechanical parameters, while men’s condition was similarly associated with musculoskeletal tests results and biomechanical parameters. However, similarities like the performance on the 30s_CST and the role of flexion angle ROM during loading were reported. This study supports the value of adding a biomechanical assessment to the musculoskeletal examination to better understand the clinical state of the knee and to prioritize which mechanical factors to be addressed to improve patient’s condition

Prioritization of candidate causal genes for asthma in susceptibility loci derived from UK Biobank

Kim Valette et al. perform a genomic study on asthma integrating genome-wide association study, functional mapping using lung and blood transcriptome-wide profiles, as well as Mendelian randomization. They show candidate causal genes expressed in lung and blood tissues that are putative therapeutic targets for asthma

Macrophage-Specific ApoE Gene Repair Reduces Diet-Induced Hyperlipidemia and Atherosclerosis in Hypomorphic Apoe Mice

Apolipoprotein (apo) E is best known for its ability to lower plasma cholesterol and protect against atherosclerosis. Although the liver is the major source of plasma apoE, extra-hepatic sources of apoE, including from macrophages, account for up to 10% of plasma apoE levels. This study examined the contribution of macrophage-derived apoE expression levels in diet-induced hyperlipidemia and atherosclerosis.Hypomorphic apoE (Apoe(h/h)) mice expressing wildtype mouse apoE at ∼2-5% of physiological levels in all tissues were derived by gene targeting in embryonic stem cells. Cre-mediated gene repair of the Apoe(h/h) allele in Apoe(h/h)LysM-Cre mice raised apoE expression levels by 26 fold in freshly isolated peritoneal macrophages, restoring it to 37% of levels seen in wildtype mice. Chow-fed Apoe(h/h)LysM-Cre and Apoe(h/h) mice displayed similar plasma apoE and cholesterol levels (55.53±2.90 mg/dl versus 62.70±2.77 mg/dl, n = 12). When fed a high-cholesterol diet (HCD) for 16 weeks, Apoe(h/h)LysM-Cre mice displayed a 3-fold increase in plasma apoE and a concomitant 32% decrease in plasma cholesterol when compared to Apoe(h/h) mice (602.20±22.30 mg/dl versus 888.80±24.99 mg/dl, n = 7). On HCD, Apoe(h/h)LysM-Cre mice showed increased apoE immunoreactivity in lesional macrophages and liver-associated Kupffer cells but not hepatocytes. In addition, Apoe(h/h)LysM-Cre mice developed 35% less atherosclerotic lesions in the aortic root than Apoe(h/h) mice (167×10(3)±16×10(3) µm(2) versus 259×10(3)±56×10(3) µm(2), n = 7). This difference in atherosclerosis lesions size was proportional to the observed reduction in plasma cholesterol.Macrophage-derived apoE raises plasma apoE levels in response to diet-induced hyperlipidemia and by such reduces atherosclerosis proportionally to the extent to which it lowers plasma cholesterol levels

Community-developed checklists for publishing images and image analysis

Images document scientific discoveries and are prevalent in modern biomedical research. Microscopy imaging in particular is currently undergoing rapid technological advancements. However for scientists wishing to publish the obtained images and image analyses results, there are to date no unified guidelines. Consequently, microscopy images and image data in publications may be unclear or difficult to interpret. Here we present community-developed checklists for preparing light microscopy images and image analysis for publications. These checklists offer authors, readers, and publishers key recommendations for image formatting and annotation, color selection, data availability, and for reporting image analysis workflows. The goal of our guidelines is to increase the clarity and reproducibility of image figures and thereby heighten the quality of microscopy data is in publications.Comment: 28 pages, 8 Figures, 3 Supplmentary Figures, Manuscript, Essential recommendations for publication of microscopy image dat