A Microstructural View of Burrowing with RoboClam

RoboClam is a burrowing technology inspired by Ensis directus, the Atlantic razor clam. Atlantic razor clams should only be strong enough to dig a few centimeters into the soil, yet they burrow to over 70 cm. The animal uses a clever trick to achieve this: by contracting its body, it agitates and locally fluidizes the soil, reducing the drag and energetic cost of burrowing. RoboClam technology, which is based on the digging mechanics of razor clams, may be valuable for subsea applications that could benefit from efficient burrowing, such as anchoring, mine detonation, and cable laying. We directly visualize the movement of soil grains during the contraction of RoboClam, using a novel index-matching technique along with particle tracking. We show that the size of the failure zone around contracting RoboClam, can be theoretically predicted from the substrate and pore fluid properties, provided that the timescale of contraction is sufficiently large. We also show that the nonaffine motions of the grains are a small fraction of the motion within the fluidized zone, affirming the relevance of a continuum model for this system, even though the grain size is comparable to the size of RoboClam

Toll-like receptors and their soluble forms differ in the knee and thumb basal osteoarthritic joints

Background and purpose - Although the pathogenesis of osteoarthritis (OA) is not well understood, chondrocyte-mediated inflammatory responses (triggered by the activation of innate immune receptors by damage-associated molecules) are thought to be involved. We examined the relationship between Toll-like receptors (TLRs) and OA in cartilage from 2 joints differing in size and mechanical loading: the first carpometacarpal (CMC-I) and the knee. Patients and methods - Samples of human cartilage obtained from OA CMC-I and knee joints were immunostained for TLRs (1-9) and analyzed using histomorphometry and principal component analysis (PCA). mRNA expression levels were analyzed with RT-PCR. Collected synovial fluid (SF) samples were screened for the presence of soluble forms of TLR2 and TLR4 by enzyme-linked immunosorbent assay (ELISA). Results - In contrast to knee OA, TLR expression in CMC-I OA did not show grade-dependent overall profile changes, but PCA revealed that TLR expression profiles clustered according to their cellular compartment organization. Protein levels of TLR4 were substantially higher in knee OA than in CMC-I OA, while the opposite was the case at the mRNA level. ELISA assays confirmed the presence of soluble forms of TLR2 and TLR4 in SF, with sTLR4 being considerably higher in CMC-I OA than in knee OA. Interpretation - We observed that TLRs are differentially expressed in OA cartilage, depending on the joint. Soluble forms of TLR2 and TLR4 were detected for the first time in SF of osteoarthritic joints, with soluble TLR4 being differentially expressed. Together, our results suggest that negative regulatory mechanisms of innate immunity may be involved in the pathomolecular mechanisms of osteoarthritis.Peer reviewe

IL-17A and TNF synergistically drive expression of proinflammatory mediators in synovial fibroblasts via I kappa B zeta-dependent induction of ELF3

Objective IL-17A and TNF act in synergy to induce proinflammatory mediators in synovial fibroblasts thus contributing to diseases associated with chronic arthritis. Many of these factors are regulated by transcription factor E74-like factor-3 (ELF3). Therefore, we sought to investigate ELF3 as a downstream target of IL-17A and TNF signalling and to characterize its role in the molecular mechanism of synergy between IL-17A and TNF. Methods Regulation of ELF3 expression by IL-17A and TNF was studied in synovial fibroblasts of RA and OA patients and RA synovial explants. Signalling leading to ELF3 mRNA induction and the impact of ELF3 on the response to IL-17A and TNF were studied using siRNA, transient overexpression and signalling inhibitors in synovial fibroblasts and HEK293 cells. Results ELF3 was marginally affected by IL-17A or TNF alone, but their combination resulted in high and sustained expression. ELF3 expression was regulated by the nuclear factor-kappa B (NF-kappa B) pathway and CCAAT/enhancer-binding protein beta (C/EBP beta), but its induction required synthesis of the NF-kappa B co-factor I kappa B (inhibitor of NF-kappa B) zeta. siRNA-mediated depletion of ELF3 attenuated the induction of cytokines and matrix metalloproteinases by the combination of IL-17A and TNF. Overexpression of ELF3 or I kappa B zeta showed synergistic effect with TNF in upregulating expression of chemokine (C-C motif) ligand 8 (CCL8), and depletion of ELF3 abrogated CCL8 mRNA induction by the combination of I kappa B zeta overexpression and TNF. Conclusion Altogether, our results establish ELF3 as an important mediator of the synergistic effect of IL-17A and TNF in synovial fibroblasts. The findings provide novel information of the pathogenic mechanisms of IL-17A in chronic arthritis and implicate ELF3 as a potential therapeutic target.Peer reviewe

Evidence-based Practices in Mentoring Students with Disabilities: Four Case Studies

Individuals with disabilities are attending postsecondary institutions at higher rates than ever before, although many struggle to adjust in college environments. On one hand, higher education positively correlates with better employment outcomes, while on the other, higher education represents more stringent academic requirements and more diffused disability supports. One intervention used to check the ‘trauma’ of transition from high school to postsecondary education is mentoring. This article describes four successful mentorship programs, in various stages of maturity, which are currently funded by the National Science Foundation. The case studies describe the structure of each program, recruitment strategies, the students involved, and outcomes achieved to date. Implications or ‘lessons learned’ are also discussed to provide other important information and impetus for those anticipating such programs

Treponema denticola chymotrypsin-like proteinase may contribute to orodigestive carcinogenesis through immunomodulation

Background: Periodontal pathogens have been linked to oral and gastrointestinal (orodigestive) carcinogenesis. However, the exact mechanisms remain unknown. Treponema denticola (Td) is associated with severe periodontitis, a chronic inflammatory disease leading to tooth loss. The anaerobic spirochete Td is an invasive bacteria due to its major virulence factor chymotrypsin-like proteinase. Here we aimed to investigate the presence of Td chymotrypsin-like proteinase (Td-CTLP) in major orodigestive tumours and to elucidate potential mechanisms for Td to contribute to carcinogenesis. Methods: The presence of Td-CTLP within orodigestive tumour tissues was examined using immunohistochemistry. Oral, tonsillar, and oesophageal squamous cell carcinomas, alongside gastric, pancreatic, and colon adenocarcinomas were stained with a Td-CTLP-specific antibody. Gingival tissue from periodontitis patients served as positive controls. SDS-PAGE and immunoblot were used to analyse the immumodulatory activity of Td-CTLP in vitro. Results: Td-CTLP was present in majority of orodigestive tumour samples. Td-CTLP was found to convert pro MMP-8 and -9 into their active forms. In addition, Td-CTLP was able to degrade the proteinase inhibitors TIMP-1, TIMP-2, and alpha-1-antichymotrypsin, as well as complement C1q. Conclusions: Because of its presence within tumours and regulatory activity on proteins critical for the regulation of tumour microenvironment and inflammation, the Td-CTLP may contribute to orodigestive carcinogenesis.Peer reviewe

The Cost-Effectiveness of Biologics for the Treatment of Rheumatoid Arthritis : A Systematic Review

Background and Objectives Economic evaluations provide information to aid the optimal utilization of limited healthcare resources. Costs of biologics for Rheumatoid arthritis (RA) are remarkably high, which makes these agents an important target for economic evaluations. This systematic review aims to identify existing studies examining the cost-effectiveness of biologics for RA, assess their quality and report their results systematically. Methods A literature search covering Medline, Scopus, Cochrane library, ACP Journal club and Web of Science was performed in March 2013. The cost-utility analyses (CUAs) of one or more available biological drugs for the treatment of RA in adults were included. Two independent investigators systematically collected information and assessed the quality of the studies. To enable the comparison of the results, all costs were converted to 2013 euro. Results Of the 4890 references found in the literature search, 41 CUAs were included in the current systematic review. While considering only direct costs, the incremental cost-effectiveness ratio (ICER) of the tumor necrosis factor inhibitors (TNFi) ranged from 39,000 to 1 273,000 (sic)/quality adjusted life year (QALY) gained in comparison to conventional disease-modifying antirheumatic drugs (cDMARDs) in cDMARD naive patients. Among patients with an insufficient response to cDMARDs, biologics were associated with ICERs ranging from 12,000 to 708,000 (sic)/QALY. Rituximab was found to be the most cost-effective alternative compared to other biologics among the patients with an insufficient response to TNFi. Conclusions When 35,000 (sic)/QALY is considered as a threshold for the ICER, TNFis do not seem to be cost-effective among cDMARD naive patients and patients with an insufficient response to cDMARDs. With thresholds of 50,000 to 100,000 (sic)/QALY biologics might be cost-effective among patients with an inadequate response to cDMARDs. Standardization of multiattribute utility instruments and a validated standard conversion method for missing utility measures would enable better comparison between CUAs.Peer reviewe

Head-to-head comparison of aggressive conventional therapy and three biological treatments and comparison of two de-escalation strategies in patients who respond to treatment : study protocol for a multicenter, randomized, open-label, blinded-assessor, phase 4 study

Background: New targeted therapies and improved treatment strategies have dramatically improved the outcomes of patients with rheumatoid arthritis (RA). However, it is unknown whether different early aggressive interventions can induce stable remission or a low-active disease state that can be maintained with conventional synthetic disease-modifying antirheumatic drug (csDMARD) therapy, and whether they differ in efficacy and safety. The Nordic Rheumatic Diseases Strategy Trials And Registries (NORD-STAR) study will assess and compare (1) the proportion of patients who achieve remission in a head-to-head comparison between csDMARD plus glucocorticoid therapy and three different biological DMARD (bDMARD) therapies with different modes of action and (2) two de-escalation strategies in patients who respond to first-line therapy. Methods/design: In a pragmatic, 80-160-week, multicenter, randomized, open-label, assessor-blinded, phase 4 study, 800 patients with early RA (symptom duration less than 24 months) are randomized 1: 1: 1: 1 to one of four different treatment arms: (1) aggressive csDMARD therapy with methotrexate + sulphasalazine + hydroxychloroquine + i. a. glucocorticoids (arm 1A) or methotrexate + prednisolone p.o. (arm 1B), (2) methotrexate + certolizumab-pegol, (3) methotrexate + abatacept, or (4) methotrexate + tocilizumab. The primary clinical endpoint is the proportion of patients reaching Clinical Disease Activity Index (CDAI) remission at week 24. Patients in stable remission over 24 consecutive weeks enter part 2 of the study earliest after 48 weeks. Patients not achieving sustained CDAI remission over 24 consecutive weeks, exit the study after 80 weeks. In part 2, patients are re-randomized to two different de-escalation strategies, either immediate or delayed (after 24 weeks) tapering, followed by cessation of study medication. All patients remain on stable doses of methotrexate. The primary clinical endpoint in part 2 is the proportion of patients in remission (CDAI Discussion: NORD-STAR is the first investigator-initiated, randomized, early RA trial to compare (1) csDMARD and three different bDMARD therapies head to head and (2) two different de-escalation strategies. The trial has the potential to identify which treatment strategy to apply in early RA to achieve the best possible outcomes for both patients and society.Peer reviewe

One-Year Treatment Outcomes of Secukinumab Versus Tumor Necrosis Factor Inhibitors in Spondyloarthritis : Results From Five Nordic Biologic Registries Including More Than 10,000 Treatment Courses

Objective To describe baseline characteristics and to compare treatment effectiveness of secukinumab versus tumor necrosis factor inhibitors (TNFi) in patients with spondyloarthritis (SpA) using adalimumab as the main comparator. Methods This was an observational, prospective cohort study. Patients with SpA (clinical ankylosing spondylitis, nonradiographic axial SpA, or undifferentiated SpA) starting secukinumab or a TNFi during 2015-2018 were identified from 5 Nordic clinical rheumatology registries. Data on comorbidities and extraarticular manifestations (psoriasis, uveitis, and inflammatory bowel disease) were captured from national registries (data available in 94% of patients) and included in multivariable analyses. We assessed 1-year treatment retention (crude survival curves, adjusted hazard ratios [HRadj] for treatment discontinuation) and 6-month response rates (Ankylosing Spondylitis Disease Activity Score [ASDAS] scorePeer reviewe

Is the risk of infection higher during treatment with secukinumab than with TNF inhibitors? An observational study from the Nordic countries

Objectives The positioning of secukinumab in the treatment of axial SpA (axSpA) and PsA is debated, partly due to a limited understanding of the comparative safety of the available treatments. We aimed to assess the risk of the key safety outcome infections during treatment with secukinumab and TNF inhibitors (TNFi). Methods Patients with SpA and PsA starting secukinumab or TNFi year 2015 through 2018 were identified in four Nordic rheumatology registers. The first hospitalized infection during the first year of treatment was identified through linkage to national registers. Incidence rates (IRs) with 95% CIs per 100 patient-years were calculated. Adjusted hazard ratios were estimated through Cox regression, with secukinumab as the reference. Several sensitivity analyses were performed to investigate confounding by indication. Results Among 7708 patients with SpA and 5760 patients with PsA, we identified 16 229 treatment courses of TNFi (53% bionaive) and 1948 with secukinumab (11% bionaive). For secukinumab, the first-year risk of hospitalized infection was 3.5% (IR 5.0; 3.9-6.3), compared with 1.7% (IR 2.3; 1.7-3.0) during 3201 courses with adalimumab, with the IRs for other TNFi lying in between these values. The adjusted HR for adalimumab, compared with secukinumab, was 0.58 (0.39-0.85). In sensitivity analyses, the difference from secukinumab was somewhat attenuated and in some analyses no longer statistically significant. Conclusion When used according to clinical practice in the Nordic countries, the observed first-year absolute risk of hospitalized infection was doubled for secukinumab compared with adalimumab. This excess risk seemed largely explained by confounding by indication.Peer reviewe

Toll-like receptors in human chondrocytes and osteoarthritic cartilage

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