Objective To determine the association between joint structure and gait in patients with knee osteoarthritis (OA). Methods IMI-APPROACH recruited 297 clinical knee OA patients. Gait data was... Show moreObjective To determine the association between joint structure and gait in patients with knee osteoarthritis (OA). Methods IMI-APPROACH recruited 297 clinical knee OA patients. Gait data was collected (GaitSmart®) and OA-related joint measures determined from knee radiographs (KIDA) and MRIs (qMRI/MOAKS). Patients were divided into those with/without radiographic OA (ROA). Principal component analyses (PCA) were performed on gait parameters; linear regression models were used to evaluate whether image-based structural and demographic parameters were associated with gait principal components. Results Two hundred seventy-one patients (age median 68.0, BMI 27.0, 77% female) could be analyzed; 149 (55%) had ROA. PCA identifed two components: upper leg (primarily walking speed, stride duration, hip range of motion [ROM], thigh ROM) and lower leg (calf ROM, knee ROM in swing and stance phases). Increased age, BMI, and radiographic subchondral bone density (sclerosis), decreased radiographic varus angle deviation, and female sex were statistically signifcantly associated with worse lower leg gait (i.e. reduced ROM) in patients without ROA (R2=0.24); in ROA patients, increased BMI, radiographic osteophytes, MRI meniscal extrusion and female sex showed signifcantly worse lower leg gait (R2=0.18). Higher BMI was signifcantly associated with reduced upper leg function for non-ROA patients (R2=0.05); ROA patients with male sex, higher BMI and less MRI synovitis showed signifcantly worse upper leg gait (R2=0.12). Conclusion Structural OA pathology was signifcantly associated with gait in patients with clinical knee OA, though BMI may be more important. While associations were not strong, these results provide a signifcant association between OA symptoms (gait) and joint structure. Show less
Boone, I.; Tuerlings, M.; Almeida, R.C. de; Lehmann, J.; Ramos, Y.; Nelissen, R.; ... ; Meulenbelt, I. 2023
Heterogeneous accumulation of senescent cells expressing the senescence-associated secretory phenotype (SASP) affects tissue homeostasis which leads to diseases, such as osteoarthritis (OA). In... Show moreHeterogeneous accumulation of senescent cells expressing the senescence-associated secretory phenotype (SASP) affects tissue homeostasis which leads to diseases, such as osteoarthritis (OA). In this study, we set out to characterize heterogeneity of cellular senescence within aged articular cartilage and explored the presence of corresponding metabolic profiles in blood that could function as representative biomarkers. Hereto, we set out to perform cluster analyses, using a gene-set of 131 senescence genes (N = 57) in a previously established RNA sequencing dataset of aged articular cartilage and a generated metabolic dataset in overlapping blood samples. Using unsupervised hierarchical clustering and pathway analysis, we identified two robust cellular senescent endotypes. Endotype-1 was enriched for cell proliferating pathways, expressing forkhead box protein O4 (FOXO4), RB transcriptional corepressor like 2 (RBL2), and cyclin-dependent kinase inhibitor 1B (CDKN1B); the FOXO mediated cell cycle was identified as possible target for endotype-1 patients. Endotype-2 showed enriched inflammation-associated pathways, expressed by interleukin 6 (IL6), matrix metallopeptidase (MMP)1/3, and vascular endothelial growth factor (VEGF)C and SASP pathways were identified as possible targets for endotype-2 patients. Notably, plasma-based metabolic profiles in overlapping blood samples (N = 21) showed two corresponding metabolic clusters in blood. These non-invasive metabolic profiles could function as biomarkers for patient-tailored targeting of senescence in OA. Show less
Osteoarthritis (OA) is a prevalent age-related joint disease, determined by diverse changes in pathways maintaining articular cartilage and subchondral bone. This thesis aimed to identify and study... Show moreOsteoarthritis (OA) is a prevalent age-related joint disease, determined by diverse changes in pathways maintaining articular cartilage and subchondral bone. This thesis aimed to identify and study gene networks driving interacting etiopathophysiological OA processes in cartilage and subchondral bone. Hereto, characterization of the molecular landscape of bone and cartilage of OA patients showed 305 genes with similar direction of effect, including IL11 and CHADL. Moreover, to capture biological complexity and decipher underlying OA disease mechanisms a variety of human 3D cartilage and bone organoids models were exploited and a human osteochondral construct-on-a-chip was developed. Herein, we showed that the robust OA risk gene WWP2 may initiate OA, via aberrant responses in hypoxia-associated genes and a decrease in anabolic markers. Additionally we showed, as reflected by upregulation of SPP1 and downregulation of WNT16 in cartilage, that treatment of ex vivo human osteochondral explants with human recombinant IL11 does not necessarily has a beneficial outcome. Finally, to allow implementation of knowledge on diverse OA pathophysiological processes, the potency of circulating miRNAs to report on ongoing OA pathophysiological process in joint tissues was established. Such insights are crucial to stratify respective OA patients that require different therapeutic mode of action, towards precision medicine. Show less
ObjectiveOsteoarthritis (OA) is a highly prevalent chronic condition. The subchondral bone plays an important role in onset and progression of OA making it a potential treatment target for disease... Show moreObjectiveOsteoarthritis (OA) is a highly prevalent chronic condition. The subchondral bone plays an important role in onset and progression of OA making it a potential treatment target for disease-modifying therapeutic approaches. However, little is known about changes of periarticular bone mineral density (BMD) in OA and its relation to meniscal coverage and meniscal extrusion at the knee. Thus, the aim of this study was to describe periarticular BMD in the Applied Public-Private Research enabling OsteoArthritis Clinical Headway (APPROACH) cohort at the knee and to analyze the association with structural disease severity, meniscal coverage and meniscal extrusion.DesignQuantitative CT (QCT), MRI and radiographic examinations were acquired in 275 patients with knee osteoarthritis (OA). QCT was used to assess BMD at the femur and tibia, at the cortical bone plate (Cort) and at the epiphysis at three locations: subchondral (Sub), mid-epiphysis (Mid) and adjacent to the physis (Juxta). BMD was evaluated for the medial and lateral compartment separately and for subregions covered and not covered by the meniscus. Radiographs were used to determine the femorotibial angle and were evaluated according to the Kellgren and Lawrence (KL) system. Meniscal extrusion was assessed from 0 to 3.ResultsMean BMD differed significantly between each anatomic location at both the femur and tibia (p < 0.001) in patients with KL0. Tibial regions assumed to be covered with meniscus in patients with KL0 showed lower BMD at Sub (p < 0.001), equivalent BMD at Mid (p = 0.07) and higher BMD at Juxta (p < 0.001) subregions compared to regions not covered with meniscus. Knees with KL2–4 showed lower Sub (p = 0.03), Mid (p = 0.01) and Juxta (p < 0.05) BMD at the medial femur compared to KL0/1. Meniscal extrusion grade 2 and 3 was associated with greater BMD at the tibial Cort (p < 0.001, p = 0.007). Varus malalignment is associated with significant greater BMD at the medial femur and at the medial tibia at all anatomic locations.ConclusionBMD within the epiphyses of the tibia and femur decreases with increasing distance from the articular surface. Knees with structural OA (KL2–4) exhibit greater cortical BMD values at the tibia and lower BMD at the femur at the subchondral level and levels beneath compared to KL0/1. BMD at the tibial cortical bone plate is greater in patients with meniscal extrusion grade 2/3. Show less
ObjectiveInflammatory hand arthritis (IHA) results in impaired function. Local gene therapy with ART-I02, a recombinant adeno-associated virus (AAV) serotype 5 vector expressing interferon (IFN)-β,... Show moreObjectiveInflammatory hand arthritis (IHA) results in impaired function. Local gene therapy with ART-I02, a recombinant adeno-associated virus (AAV) serotype 5 vector expressing interferon (IFN)-β, under the transcriptional control of nuclear factor κ-B responsive promoter, was preclinically shown to have favorable effects. This study aimed to investigate the safety and tolerability of local gene therapy with ART-I02 in patients with IHA.MethodsIn this first-in-human, dose-escalating, cohort study, 12 IHA patients were to receive a single intra-articular (IA) injection of ART-I02 ranging 0.3 × 1012-1.2 × 1013 genome copies in an affected hand joint. Adverse events (AEs), routine safety laboratory and the clinical course of disease were periodically evaluated. Baseline- and follow-up contrast enhanced magnetic resonance images (MRIs), shedding of viral vectors in bodily fluids, and AAV5 and IFN-β immune responses were evaluated. A data review committee provided safety recommendations.ResultsFour patients were enrolled. Long-lasting local AEs were observed in 3 patients upon IA injection of ART-I02. The AEs were moderate in severity and could be treated conservative. Given the duration of the AEs and their possible or probable relation to ART-I02, no additional patients were enrolled. No systemic treatment emergent AEs were observed. The MRIs reflected the AEs by (peri)arthritis. No T-cell response against AAV5 or IFN-β, nor IFN-β antibodies could be detected. Neutralizing antibody titers against AAV5 raised post-dose.ConclusionSingle IA doses of 0.6 × 1012 or 1.2 × 1012 ART-I02 vector genomes were administered without systemic side effects or serious AEs. However, local tolerability was insufficient for continuation. Show less
Li, R.; Boer, C.G.; Oei, L.; Medina-Gomez, C. 2021
Purpose of the review The human gut harbors a complex community of microbes that influence many processes regulating musculoskeletal development and homeostasis. This review gives an update on the... Show morePurpose of the review The human gut harbors a complex community of microbes that influence many processes regulating musculoskeletal development and homeostasis. This review gives an update on the current knowledge surrounding the impact of the gut microbiota on musculoskeletal health, with an emphasis on research conducted over the last three years. Recent findings The gut microbiota and their metabolites are associated with sarcopenia, osteoporosis, osteoarthritis, and rheumatoid arthritis. The field is moving fast from describing simple correlations to pursue establishing causation through clinical trials. The gut microbiota and their microbial-synthesized metabolites hold promise for offering new potential alternatives for the prevention and treatment of musculoskeletal diseases given its malleability and response to environmental stimuli. Show less
The pathogenesis of OA is largely unknown; however, several risk factors are known to contribute to disease development. Treatment modalities are currently limited to alleviation of symptoms. In... Show moreThe pathogenesis of OA is largely unknown; however, several risk factors are known to contribute to disease development. Treatment modalities are currently limited to alleviation of symptoms. In order to develop better treatment modalities, increase of the understanding of the underlying mechanisms leading to OA development may provide targets for disease modification. Furthermore, knowledge regarding appropriate outcome measures that can be applied in OA research has to be increased for adequate assessment of potential treatment effects. Therefore, part I of this thesis describes studies aiming to increase the understanding of mechanisms underlying the association between known risk factors and OA, especially focussing on obesity in relation to OA in weight-bearing and non-weight-bearing joints. Furthermore, it was investigated which specific structural abnormalities on specific locations within the knee joint could best discriminate presence of symptomatic OA, and impact of knee OA and its modifiable or preventable risk on health-related quality of life was evaluated. Part II of this thesis describes two systematic reviews, assessing available instruments for measurement of the domains pain, physical function, patient global assessment and imaging in hand OA in order to enable recommendations for use in clinical trials. Show less
Although osteoarthritis is a common disease, there are currently no disease-modifying availible. For a long time osteoarthritis was considered a purely degenerative disease without inflammation of... Show moreAlthough osteoarthritis is a common disease, there are currently no disease-modifying availible. For a long time osteoarthritis was considered a purely degenerative disease without inflammation of the synovium (synovitis). However, recent research has shown that synovitis is of importance in patients with osteoarthritis. Therefore, this thesis aimed to understand the role synovitis in ossteoarthritis. In the first part of this thesis, we investigated the nature of synovitis by examining the synovium of osteoarthritis patients using differnt laboratory techniques. Furthermore, we validated a new synovitis scoring system on MRI with contrast. In the second part of this thesis, we investigated role of synovitis in relation to clinical characteristics such as pain and structural damage. This thesis shows that synovial inflammation in osteoarthritis is not only frequently present, but may also play a role in the pathophysiology of osteoarthritis and development of clinical features. Results presented in this thesis provide insight into different aspects of synovial inflammation aimed at increasing our understanding of the pathophysiology of OA and aiding to the development of disease-modifying drugs in OA. Show less
Osteoarthritis (OA) is an age related disorder of the joints characterized by pain, crepitus, and stiffness resulting in decreased mobility. Pathophysiology consists of cartilage degeneration and... Show moreOsteoarthritis (OA) is an age related disorder of the joints characterized by pain, crepitus, and stiffness resulting in decreased mobility. Pathophysiology consists of cartilage degeneration and bone remodeling, however, knowledge of OA etiology is still limited. Due to the growing population of elderly, OA prevalence rapidly increases. The fact that no reliable clinical markers are available for diagnosis, monitoring and progression is a major impediment in OA disease management and incurs high costs in drug development and clinical trials. Molecular markers were studied in OA affected cartilage compared to unaffected cartilage of the same joint (chapter 2) and in blood of OA patients (chapter 3). Perturbation of the application of traditional biochemical markers sCOMP and uCTX2 in the clinic due to genetic factors that, independent of OA, affect innate levels was investigated (chapter 4). Furthermore, we have tried to go beyond the results of molecular epidemiological studies to increase insights into underlying mechanisms (chapter 6 & 7). This shows how functional genomics can be achieved by combining genetic and functional data and will facilitate translation of knowledge of genetic variants to the needs of OA patients and thus to application in the clinic. Show less
In the first part an update of a guideline for the physiotherapy treatment of patients with hip and knee OA is described. Then a set of quality indicators for the physiotherapy management is... Show moreIn the first part an update of a guideline for the physiotherapy treatment of patients with hip and knee OA is described. Then a set of quality indicators for the physiotherapy management is developed to be used as an instrument to measure guideline adherence. Subsequently the effect of educational strategies to enhance their uptake by physiotherapists in daily clinical practice is investigated. An interactive approach with patient colaboration and following a proces of clinical reasoning has shown to be the most effective strategy. The second part describes the extent of the provision of physiotherapy before and after joint replacement surgery from the physiotherapists__ and patients__ perspective. Results showed a large variation in provided interventions before and after surgery, although evidence for physiotherapy before joint replacement surgery is lacking. This indicates that more research is necessary focussing on effectiveness for specific groups of patients. In addition it was concluded that the presence of severe back pain in THA and dizziness in THA and TKA, should maybe ascertained before surgery and if present be treated if possible in order to decrease the chance of unfavourable outcome, although the predictive value of dizziness should be confirmed in a study with a prospective design. Show less
Osteoarthritis is a prevalent disease causing pain and disability. It__s aetiology is unknown and no curative treatment is available. Osteoarthritis research is complicated due to heterogeneity of... Show moreOsteoarthritis is a prevalent disease causing pain and disability. It__s aetiology is unknown and no curative treatment is available. Osteoarthritis research is complicated due to heterogeneity of the disease, slow progression and poor association of clinical features with radiographic abnormalities, imaging modality of choice until now. In this thesis the role of synovitis in osteoarthritis is studied in relationship with clinical features and structural damage. The studies described made especially use of data derived a prospective follow-up study in symptomatic hand osteoarthritis patients. Synovitis detected on ultrasound was associated with clinical features and with progression of structural damage after 2.3 years in hand osteoarthritis. In erosive osteoarthritis, a subtype of hand osteoarthritis, more synovitis was found in all hand joints, even in non-erosive joints, when compared to joints of patients without erosive osteoarthritis. Also, associations were found between synovitis and erosive development at follow-up. All analyses were performed on joint level, using GEE analyses, thereby taking into account patient effects. Associations were poor/absent when analyses were done on patient level. This is important for further research. These results indicate that synovitis plays a role in pain and in development of structural damage in osteoarthritis and could be a therapeutic target. Show less
The aim of this thesis was to investigate the limitations in daily life, outcome measures, clinical outcomes with the emphasis on patient satisfaction, and economic aspects of the treatment of hand... Show moreThe aim of this thesis was to investigate the limitations in daily life, outcome measures, clinical outcomes with the emphasis on patient satisfaction, and economic aspects of the treatment of hand osteoarthritis (OA). Patients with hand OA report severe restrictions in daily life, in particular in opening food packaging. We defined guidelines for the industry on the production of easy-to-open food packaging to make life easier for patients in the future. For evaluating the outcome of an intervention, numerous patient-reported outcome measures are used at present with questionable measurement properties. We could show that the Michigan Hand Outcomes Questionnaire demonstrates good measurement properties in patients with trapeziometacarpal (TMC) OA. Many variables determine patient satisfaction with treatment; expectations being fulfilled, relief of pain or symptoms, and the restoration of hand function are the most important determinants. Evaluation of the outcomes of conservative and surgical management in patients with TMC OA showed that surgery leads to significantly improved hand function after one year, while conservative treatment is most effective in the first 6 months. From an economic point of view, surgery is associated with considerably higher costs than conservative treatment, with respect to both healthcare costs and loss of productivity. Show less
This thesis investigates the role of adipose tissue inflammation in joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA) . In the first part, we show that baseline levels of... Show moreThis thesis investigates the role of adipose tissue inflammation in joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA) . In the first part, we show that baseline levels of circulating adiponectin can predict radiographic progression in patients with early RA. In contrast, in patients with hand OA, this association appears protective. Therefore, to obtain insight into the mechanisms underlying these associations, we investigated the high-molecular-weight isoform of adiponectin (hmwAPN), which is one of the most biologically active isoforms of adiponectin. We show that the associations of total adiponectin with radiographic progression are not mediated by hmwAPN, in either RA or HOA. In the second part, we present the immunological characterization of the infrapatellar fat pad (IFP), a joint associated adipose tissue, in patients with advanced knee OA. We observed profound differences in secreted inflammatory factors and immune cell composition between the IFP and paired subcutaneous adipose tissue samples. Interestingly, we observed obesity-related changes in the IFP phenotype, and in macrophages and adipocytes, Therefore, we investigated the modulatory effects of adipocytes on the phenotype of human macrophages in vitro and we observed that adipocyte-derived lipids can mediate the obesity-related changes in the phenotype of adipose tissue macrophages in humans Show less
Osteoarthritis (OA) is a frequently occurring joint disorder with great impact on the quality of life. In general, OA is described as a heterogeneous disease with degeneration of articular... Show moreOsteoarthritis (OA) is a frequently occurring joint disorder with great impact on the quality of life. In general, OA is described as a heterogeneous disease with degeneration of articular cartilage as main outcome. Despite extensive research on the pathogenesis of OA, there is until now no cure and treatments are primarily aimed at reducing pain. Evidence starts to appear that mild inflammation and obesity-related biochemical changes are involved in OA pathology. It is uncertain what the relative contribution of these processes is and if they characterize a certain type of OA patients. We identified obesity, high cholesterol and systemic inflammation associated with these conditions as major players in OA development, which may activate joint tissues to secrete inflammatory mediators and contribute to the initiation and progression of OA. Our work suggests that a stratification of OA patients with (features of) the metabolic syndrome as underlying mechanism is recommendable, to optimize the efficacy of clinical trials. Approaching OA as a disease induced by whole body metabolism, and integrating knowledge about different potentially active tissues in the OA process, will provide new insights for possible pharmacological interventions. Show less
Obesity is a major risk factor of osteoarthritis development and progression. Theoretically, obesity is a factor that can be modified. While obesity epidemic is difficult to reverse because we live... Show moreObesity is a major risk factor of osteoarthritis development and progression. Theoretically, obesity is a factor that can be modified. While obesity epidemic is difficult to reverse because we live in lipogenic environment, personal approach in modify obesity may avail. Therefore, understanding how obesity leads to osteoarthritis is needed. The first three chapters of this thesis investigate several aspects of osteoarthritis: what structures are damaged, what factors are associated with worsening of osteoarthritis and how to measure worsening of osteoarthritis. The other four chapters investigate the link between obesity and osteoarthritis. We show that obesity is associated with hand osteoarthritis. Since we do not walk on our hand, there must be another factor than mechanical that cause joint damage in osteoarthritis. One of the factors is adipokines, protein produced mainly by fat tissue. We showed that adiponectin, one of the adipokines, prevents worsening of hand osteoarthritis. We concluded that obesity plays role in osteoarthritis not only due to added mechanical force but also due to added metabolic force (adipokines). These adipokines might be used as target in modifying the effect of obesity on osteoarthritis. However, we still need more studies on how obesity links with osteoarthritis Show less
We investigated the clinical and radiographic disease course of hand osteoarthritis as well as determinants of poor clinical outcome and radiographic progression over a period of six years in 289... Show moreWe investigated the clinical and radiographic disease course of hand osteoarthritis as well as determinants of poor clinical outcome and radiographic progression over a period of six years in 289 patients with hand osteoarthritis. Because these patients had osteoarthritis at multiple joints this enabled us to not only assess the association between progression of osteoarhtiritis in different hand joints groups but also between progression of hand osteoarthritis and osteoarthritis change at the knee. In addition, genetic factors in hand osteoarthritis progression were investigated as well as the influence of illness perceptions. The hand osteoarthritis subsets erosive osteoarthritis and thumb base osteoarthritis are further characterised. In the last part of the thesis the clinimetric properties of a pain score for osteoarthritis and radiographic outcome measures for hand osteoarthritis are evaluated. Show less
Osteoarthritis (OA) mainly affects the articular cartilage covering the bones. In this thesis we investigated the relation between levels of inflammatory mediators, genes involved in their... Show moreOsteoarthritis (OA) mainly affects the articular cartilage covering the bones. In this thesis we investigated the relation between levels of inflammatory mediators, genes involved in their regulation and the disease status of OA. We investigated the role of genetic variation at the interleukin(IL)-1 gene cluster in the innate bio-availability of IL-1beta. A haplotype that associated to low innate bio-availability also associated to higher hand OA scores. Although this is counterintuitive with respect to the generally accepted hypothesis that a pro-inflammatory status is detrimental to the cartilage it underlines a complex relationship between inflammation and OA. For the C-reactive protein we identified a haplotype associated to high CRP levels as well as to severe hand OA, which is more in line with expected directions of associations. Analysis of baseline cytokine and chemokine levels indicated that chemokine levels associated to hand OA scores, again with low levels associated to high OA scores. In a follow up functional genomic analysis of a previously identified OA susceptibility gene (DIO2) in our studies we show that the risk allele of this gene is transcribed at higher levels as compared to the non-risk allele. Furthermore, we showed increased DIO2 protein presence in OA affected cartilage. Show less
This thesis describes the long-term consequences of growth hormone and insulin-like growth factor I excess in patients cured from acromegaly for a mean duration of 17 years. Regarding the... Show moreThis thesis describes the long-term consequences of growth hormone and insulin-like growth factor I excess in patients cured from acromegaly for a mean duration of 17 years. Regarding the considerable prevalence of diverse morbidity in these patients, during the active phase of the disease but even more so after 17 years of disease cure, we suggest the screening of acromegalic patients on highly frequent comorbidities, such as osteoarthritis, vertebral fractures, colonic polyps, and colonic diverticulae. It is of great concern to recognize the long-term consequences of the disease in order to offer the patients adequate follow-up and multidisciplinary care. The aim should be to control the persisting complex morbidity as much as possible in order to prevent the patients from a further decrease in quality of life. The patients__ physician as well as the patient itself should be aware of the long-term consequences of acromegaly in order to eliminate surreal expectations concerning recovery of certain comorbidities. Show less
Het is nu gangbaar in de kliniek om aan de hand van een enkele biochemische component (een gen, eiwit of metaboliet) vast te stellen of iemand ziek is. Echter, met geavanceerde meettechnieken zijn... Show moreHet is nu gangbaar in de kliniek om aan de hand van een enkele biochemische component (een gen, eiwit of metaboliet) vast te stellen of iemand ziek is. Echter, met geavanceerde meettechnieken zijn we nu in staat zijn om tientallen tot zelfs honderden van deze componenten tegelijk te meten. Hierdoor krijgen onderzoekers een veel breder overzicht van wat er allemaal verandert tijdens een ziekte en kunnen er betere diagnostische tests worden ontwikkeld. Voor dit proefschrift heb ik mij verdiept in deze technieken en hun toepasbaarheid in artrose. Artrose is een veel voorkomende rheumatische aandoening waarvan de exacte oorzaak nog onduidelijk is. Ik heb vastgesteld dat er met name nog weinig bekend is over het aandeel van de afbraakproducten van eiwitten en van vetten. Ik heb de benodige meettechnieken opgezet om honderden van deze afbraaktproducten en vetten te kunnen meten. Hieruit bleek dat een onstekingsmediator zeer verhoogd is in artrose en dat de samenstelling van vetten in het bloed van artrose patienten anders is dan bij gezonde mensen. De vindingen van dit proefschrift geven de kracht van deze meettechnieken aan om bij te dragen tot verbeterde diagnostische tests. Show less