The senescence-associated secretory phenotype and its regulation

The senescence-associated secretory phenotype (SASP) defines the ability of senescent cells to express and secrete a variety of extracellular modulators that includes cytokines, chemokines, proteases, growth factors and bioactive lipids. The role of the SASP depends on the context. The SASP reinforces the senescent cell cycle arrest, stimulates the immune-mediated clearance of potentially tumorigenic cells, limits fibrosis and promotes wound healing and tissue regeneration. On the other hand, the SASP can mediate chronic inflammation and stimulate the growth and survival of tumor cells. The regulation of the SASP occurs at multiple levels including chromatin remodelling, activation of specific transcription factors such as C/EBP and NF-κB, control of mRNA translation and intracellular trafficking. Several SASP modulators have already been identified setting the stage for future research on their clinical applications.

Effectiveness of treatment with biologic- and disease-modifying antirheumatic drugs in rheumatoid arthritis patients in Colombia

AIMS

Rheumatoid arthritis (RA) is an autoimmune disease cause of disability and high costs. To determine the effectiveness of therapy with biologic- and disease-modifying antirheumatic drugs (DMARDs) in patients with RA and factors associated with the control of the disease.

METHODS

Retrospective cohort study of RA patients receiving treatment with DMARDs in a rheumatologic healthcare institution in five Colombian cities from December 2009 to August 2013. The effectiveness was assessed by Disease Activity Score-28 (DAS-28) and a lower value of 2.6 was considered remission.

RESULTS

A total of 827 patients were studied for an average observation period of 17.3 ± 11.0 months, with mean age 54.3 ± 13.1 years. The most frequently used DMARDs were methotrexate, leflunomide and chloroquine. The most frequently used biological DMARDs were etanercept and abatacept. Initially, 17.8% of the patients received some biological DMARDs in comparison with 28.7% at the end of the observation period. A median DAS28 of 3.5 was found, which was reduced by the end of the observation period to 2.8 (p < 0.001), and cases of patients who were in remission increased from 30.1% to 42.9%. Treatment with leflunomide (OR: 0.47; CI 95%: 0.35-0.64, p < 0.001) or rituximab (OR: 0.37; CI 95%: 0.17-0.83, p = 0.016) was associated with a lesser probability of reaching remission. To be treated in the city of Manizales (OR: 2.56; CI 95%: 1.36-4.82, p = 0.004) was associated with a high probability of remission.

CONCLUSIONS

Biological and DMARDs therapy for RA was effective in a relevant proportion of Colombian patients as a consequence of management with strategies set on remission aims quantified using DAS28. Cost-effectiveness of the therapy must be evaluated.

A new platform based on IEEE802.15.4 wireless inertial sensors for motion caption and assessment

Systems for motion caption and assessment in biomechanics are mostly based on photogrammetry. These systems are restricted to the movement analysis lab and moreover, they are very expensive. New advances in MEMs (Microelectromechanical) and wireless technologies enable inertial sensing as an alternatives for motion caption. This paper presents a wireless inertial sensor including 3 linear accelerometers, 3 gyroscopes and 3 magnetometers. The IMU (inertial measurement unit) includes a IEEE802.15.4 compliant transceiver. The platform expands the frontiers of movement analysis for motion caption in real scenarios like sports and wearable robotics since it does not need structurated labs. Besides the advantages, the cost of the platform is much lower comparing actual photogrammetry systems.

Design and validation of a rehabilitation robotic exoskeleton for tremor assessment and suppression

Exoskeletons are mechatronic systems worn by a person in such a way that the physical interface permits a direct transfer of mechanical power and exchange of information. Upper limb robotic exoskeletons may be helpful for people with disabilities and/or limb weakness or injury. Tremor is the most common movement disorder in neurological practice. In addition to medication, rehabilitation programs, and deep brain stimulation, biomechanical loading has appeared as a potential tremor suppression alternative. This paper introduces the robotic exoskeleton called WOTAS (wearable orthosis for tremor assessment and suppression) that provides a means of testing and validating nongrounded control strategies for orthotic tremor suppression. This paper describes in detail the general concept for WOTAS, outlining the special features of the design and selection of system components. Two control strategies developed for tremor suppression with exoskeletons are described. These two strategies are based on biomechanical loading and notch filtering the tremor through the application of internal forces. Results from experiments using these two strategies on patients with tremor are summarized. Finally, results from clinical trials are presented, which indicate the feasibility of ambulatory mechanical suppression of tremor.