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The aim of this study is to design a new dynamic mechanical analysis (DMA) measurement system that can operate for shear tests at frequencies as high as 10 kHz with strain amplitudes sufficient for viscoelastic materials operating in high-frequency deformation applications, such as tire rubbers. The available DMA systems in market cannot effectively operate for accurate and direct measurement of viscoelastic material properties for applications dealing with high-frequency deformation of materials. Due to this, the available DMA systems are used for indirect measurements at low frequencies and low temperatures, followed by using time-temperature superposition principle to predict the properties at high frequencies. The goal of this study is to make the range of the test broad enough to eliminate the use of the time-temperature superposition principle in the determination of properties of viscoelastic materials. Direct measurement of viscoelastic material properties and increasing the accuracy of results are the main motivations to design a new DMA system. For this purpose, the state-of-the-art technologies to achieve high frequencies and strain amplitudes as well as instrumentation and control of the system are studied. The design process is presented in this paper.

This study presents effects of intravenous laser blood irradiation (ILBI) in a transient immunodeficiency patient with juvenile idiopathic arthritis (JIA) treated with an interleukin-6 receptor inhibitor (Tocilizumab). Biological agents induce JIA remission, but some patients do not respond favorably to this final therapeutic line of defense. ILBI was performed in a 16-year-old male patient, with JIA and transient immunodeficiency. When ILBI was introduced, the patient was receiving disease-modifying drugs, steroids, tocilizumab, and physical therapy. Because the disease was not well controlled, ILBI was applied in addition to other ongoing therapies. The patient underwent 1 session daily, and 10 successive sessions per month, repeated every 3 months, for 7 months. Patient evaluation was performed before ILBI was started and at 3, 6, 9, and 12 months after ILBI initiation, using the ACR Pediatric response. The outcome was evaluated using Pediatric 50, 70, and 90 responses and compared to initial status, after 3, 6, 9, and 12 months. At the end of study, the titre of IgA and IgG levels returned to normal. Synergistic anti-inflammatory effect of ILBI was evident, if applied additionally in combination with tocilizumab, in a patient with a therapy-resistant severe form of JIA and related subacute transient immunodeficiency.

Sublingual laser blood irradiation (SLBI) was applied into a randomized, single-blind, placebo-controlled study in juvenile idiopathic arthritis (JIA), aimed at inducing disease remission. 105 children with JIA, without an adequate response to classical treatment, were administrated a disease modifying drug (Methotrexate) and were randomly assigned to three groups. Group I (36 patients) received SLBI with the Weberneedle Lasershower Mouth Applicator with three wavelengths (635 nm, 536 nm, and 405 nm), 5 mW maximum output power each, in continuous mode, simultaneously, for 20 minutes daily, 7 successive sessions per month, repeated every 7 weeks, for three times. Group II (36 patients) received placebo SLBI. Group III (33 patients) received only treatment with Methotrexate. Evaluation was performed using American College of Rheumatology Pediatric criteria (ACR Pedi) at study enrollment and at 8, 16, 24, and 48 weeks. At the end of study, there was an improvement of the ACR Pedi 30 by 86.11% in SLBI group compared to only 61.11% in Group II, respectively, and 60.6% in Group III (P=0.001), with significant statistical differences. SLBI has reduced the pain, lowered the number of articulations with movement limitation, increased the quality of life, and made it possible to avoid the administration of biological agents.

A patient who had a small bowel mesentery perforation following insertion of a suprapubic catheter (SPC) is described. He had no bowel complaints immediately following the procedure, but presented 10 weeks later with insidious onset bowel obstruction due to the kink caused by the catheter. This complication occurred despite cystoscopy control and adequate bladder distension prior to the procedure. This isolated case illustrates the fact that regardless of the ease and frequency of SPC insertion, complications do occur.

This single-blind, placebo-controlled study assesses the efficacy of synergic administration of intravenous laser blood irradiation (ILBI) and etanercept in selected subtypes of juvenile idiopathic arthritis (JIA). Etanercept is a tumor necrosis factor alpha blocking agent with recognized importance in JIA. Laser radiation has immunomodulatory effects in animal and human studies. Fourteen patients (Group I) received ILBI and 9 patients (Group II) received placebo laser. ILBI was performed in addition to ongoing JIA medication, including etanercept. ILBI was administrated in 3 sets of 5 consecutive daily sessions, with a 7-week interval between every set of sessions. Evaluation was performed using ACR (American College of Rheumatology) Pediatric Criteria (ACR Pedi) at study enrollment and at 10 and 20 weeks, respectively. After 10 weeks, 85.7% of the patients in Group I fulfilled Pedi 30 criteria, compared to only 55.6% of the patients in Group II. After 20 weeks, all patients in both groups had a Pedi 30 response. In Group I, 92.8% of the subjects met the Pedi 50 response, compared to only 55.6% in the placebo group. One patient in Group I responded best, fulfilling Pedi 70 criteria. If applied synergistically, ILBI and etanercept would have an increased efficacy in promoting JIA remission.