Influence of Anode Immersion Speed on Current and Power in Plasma Electrolytic Polishing.

Plasma electrolytic polishing (PeP) is mainly used to improve the surface quality and thus the performance of electrically conductive parts. It is usually used as an anodic process, i.e., the workpiece is positively charged. However, the process is susceptible to high current peaks during the formation of the vapour-gaseous envelope, especially when polishing workpieces with a large surface area. In this study, the influence of the anode immersion speed on the current peaks and the average power during the initialisation of the PeP process is investigated for an anode the size of a microreactor mould insert. Through systematic experimentation and analysis, this work provides insights into the control of the initialisation process by modulating the anode immersion speed. The results clarify the relationship between immersion speed, peak current, and average power and provide a novel approach to improve process efficiency in PeP. The highest peak current and average power occur when the electrolyte splashes over the top of the anode and not, as expected, when the anode touches the electrolyte. By immersion of the anode while the voltage is applied to the anode and counterelectrode, the reduction of both parameters is over 80%.

Quo vadis reactive arthritis?

PURPOSE OF REVIEW: We provide an overview of recent articles which describe new thinking regarding HLA-B27-associated reactive arthritis (ReA), including those additional infection-related arthritides triggered by microbes that often are grouped under the term ReA. RECENT FINDINGS: With the advent and continuation of the pandemic, an increasing number of cases and case series of post-COVID-19 arthritis have been reported and classified as ReA. Further, arthritis after COVID-19 vaccination is a new entity included within the spectrum of ReA. New causative microorganisms identified in case reports include Clostridium difficile, Mycoplasma pneumoniae, Giardia lamblia, Leptospira , and babesiosis. SARS-CoV-2 is emerging as a significant etiologic agent for apparent ReA. SUMMARY: It is now clear that comprehensive clinical and laboratory investigations, synovial fluid analyses, and close follow-up of patients all are essential to differentiate ReA from diseases that may present with similar clinical attributes. Further, and importantly, additional research is required to define the wide diversity in causative agents, epidemiology, and rare case presentations of these arthritides. Finally, new classification and diagnostic criteria, and updated treatment recommendations, are essential to the advancement of our understanding of ReA.

Psoriatic Spondylitis: A Disease Manifestation in Debate: Evidences to Know for the Clinical Rheumatologist.

ABSTRACT: With the advent of classification criteria for psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA), patients with axial manifestations associated with psoriasis, initially described in the l950s as a specific entity termed psoriatic spondylitis (PS), are now categorized within PsA, ankylosing spondylitis (AS), and axSpA. Thus, different terms are used to describe axial disease in patients with PsA including PS, axial psoriatic arthritis (axPsA), and psoriatic spondyloarthritis. Patients with PS may present with inflammatory and/or mechanical back pain, but also may display axial disease on imaging despite not complaining of back pain. Cervical spondylitis has been reported in 35% to 75% of patients with PsA. Axial disease is silent in 20% and 25% of patients with axial PsA and PsA, respectively. The majority of axPsA patients have peripheral arthritis alongside the axial involvement, whereas only 2% to 5% of PsA patients have solely axial arthritis with no peripheral arthritis.A debate is currently underway as to whether inflammatory axial disease and psoriasis represent axSpA with psoriasis or a subset of PsA named axPsA. Studies have recognized that axial disease in PsA patients seems to be different demographically, genetically, clinically, and radiographically when compared with AS with or without psoriasis. This narrative review summarizes current knowledge regarding axial involvement of PsA in terms of history, terminology, classification, epidemiology, clinical presentation, imaging, diagnosis, and treatment, with the aim of providing advice for management of PS in clinical evidence-based practice. Data-driven studies are needed to develop clear, nonoverlapping classification criteria for spinal involvement in PsA.

Plasma Electrolytic Polishing of Nitinol: Investigation of Functional Properties.

A novel, environmentally friendly, fast, and flexible polishing process for Nitinol parts is presented in this study. Nitinol samples with both superelastic and shape memory properties at room temperature were investigated. The chemical contamination and surface roughness of superelastic Nitinol plates were examined before and after plasma electrolytic polishing. The shift in phase transformation temperature and tensile strength before and after the polishing process were analysed using Nitinol wire with shape memory properties. The obtained experimental results were compared to the data obtained on reference samples examined in the as-received condition. It was found that plasma electrolytic polishing, when the right process parameters are applied, is capable of delivering Nitinol parts with extremely high surface quality. Moreover, it was experimentally proven that plasma electrolytic polishing does not have a negative impact on functionality or mechanical properties of polished parts.

Investigation of Post-Processing of Additively Manufactured Nitinol Smart Springs with Plasma-Electrolytic Polishing.

Additive manufacturing of Nitinol is a promising field, as it can circumvent the challenges associated with its conventional production processes and unlock unique advantages. However, the accompanying surface features such as powder adhesions, spatters, ballings, or oxide discolorations are undesirable in engineering applications and therefore must be removed. Plasma electrolytic polishing (PeP) might prove to be a suitable finishing process for this purpose, but the effects of post-processing on the mechanical and functional material properties of additively manufactured Nitinol are still largely unresearched. This study seeks to address this issue. The changes on and in the part caused by PeP with processing times between 2 and 20 min are investigated using Nitinol compression springs manufactured by Laser Beam Melting. As a benchmark for the scanning electron microscope images, the differential scanning calorimetry (DSC) measurements, and the mechanical load test cycles, conventionally fabricated Nitinol springs of identical geometry with a medical grade polished surface are used. After 5 min of PeP, a glossy surface free of powder adhesion is achieved, which is increasingly levelled by further polishing. The shape memory properties of the material are retained without a shift in the transformation temperatures being detectable. The decreasing spring rate is primarily attributable to a reduction in the effective wire diameter. Consequently, PeP has proven to be an applicable and effective post-processing method for additively manufactured Nitinol.

Reactive Arthritis Update: Spotlight on New and Rare Infectious Agents Implicated as Pathogens.

PURPOSE OF REVIEW: This article presents a comprehensive narrative review of reactive arthritis (ReA) with focus on articles published between 2018 and 2020. We discuss the entire spectrum of microbial agents known to be the main causative agents of ReA, those reported to be rare infective agents, and those reported to be new candidates causing the disease. The discussion is set within the context of changing disease terminology, definition, and classification over time. Further, we include reports that present at least a hint of effective antimicrobial therapy for ReA as documented in case reports or in double-blind controlled studies. Additional information is included on microbial products detected in the joint, as well as on the positivity of HLA-B27. RECENT FINDINGS: Recent reports of ReA cover several rare causative microorganism such as Neisseria meningitides, Clostridium difficile, Escherichia coli, Hafnia alvei, Blastocytosis, Giardia lamblia, Cryptosporidium, Cyclospora cayetanensis, Entamoeba histolytica/dispar, Strongyloides stercoralis, ß-haemolytic Streptococci, Mycobacterium tuberculosis, Mycoplasma pneumoniae, Mycobacterium bovis bacillus Calmette-Guerin, and Rickettsia rickettsii. The most prominent new infectious agents implicated as causative in ReA are Staphylococcus lugdunensis, placenta- and umbilical cord-derived Wharton's jelly, Rothia mucilaginosa, and most importantly the SARS-CoV-2 virus. In view of the increasingly large spectrum of causative agents, diagnostic consideration for the disease must include the entire panel of post-infectious arthritides termed ReA. Diagnostic procedures cannot be restricted to the well-known HLA-B27-associated group of ReA, but must also cover the large number of rare forms of arthritis following infections and vaccinations, as well as those elicited by the newly identified members of the ReA group summarized herein. Inclusion of these newly identified etiologic agents must necessitate increased research into the pathogenic mechanisms variously involved, which will engender important insights for treatment and management of ReA.

Henri Matisse's medical history: Multiple health problems and impact on creativity.

Matisse (1869-1954) is regarded-along with Pablo Picasso-as one of the most influential contemporary artists of the 20th century. Books, biographies and illustrations often show the artist in a wheelchair or in bed, producing cut-papers with a pair of scissors or painting with a specially extended brush. Usually it is reported that abdominal surgery left Matisse chair- and bed-bound. The life of Matisse was marked by various further health problems that have never been considered in full in a medical journal. Moreover, his biography is full of examples of the reverse interaction between health and art, whereby not only health problems influenced his art but also how his artistic activity had an impact on his health and mental condition. Therefore, a comprehensive view on the relationship between health and art in the life and art of Matisse is attempted here. Matisse's medical history not only provides an instructive example of life-long multiple somatic and psychosomatic health issues, but also contributes to the humanistic view of medicine by demonstrating how he impressively captured the problems of his artistic work and life through vitality and creative power.

Chlamydia-Induced Reactive Arthritis: Disappearing Entity or Lack of Research?

PURPOSE OF REVIEW: Recent studies regarding the frequency of Chlamydia-induced reactive arthritis (ReA) are reviewed, with a focus on the question of whether the entity is in fact disappearing or whether it is simply being underdiagnosed/underreported. Epidemiological reports indicate diversity in the frequency of Chlamydia-associated ReA in various parts of the world, with evidence of declining incidence in some regions. RECENT FINDINGS: The hypothesis that early effective treatment with antibiotics prevents the manifestation of Chlamydia-associated ReA requires further investigation. For clinicians, it is important to remember that ReA secondary to Lymphogranuloma venereum (LGV) serovars L1-L3 of C. trachomatis is probably underestimated due to a limited awareness of this condition, the re-emergence in Western countries of LGV overall, and the present increasingly rare classical inguinal presentation.

[Guideline-Orientated Prescription of Disease-Modifying Drugs in Patients with Rheumatoid Arthritis - an Analysis Based on Social Health Insurance Claims Data]. / Leitliniengerechte Verordnung von krankheitsmodifizierenden Arzneimitteln bei Patienten mit rheumatoider Arthritis ­ eine Analyse auf Basis von GKV-Routinedaten.

BACKGROUND: With the market entry of biologics, the treatment of rheumatoid arthritis (RA) has changed fundamentally in terms of efficacy and costs. THE AIM: of this study is to analyse the treatment according the guideline of the German society of rheumatology for RA patients with disease-modifying anti-rheumatic drugs (DMARDs) using claims data from the statutory health insurance. MATERIALS AND METHODS: The claims data of the Techniker Krankenkasse were analysed retrospectively for the years 2011 - 2014. Subgroup analyses were used to conduct prescription and treatment differences with respect to guideline-recommended conventional DMARDs and biologics. RESULTS: The study population included 55,538 RA patients (29.7 % incidence, 70.3 % prevalence, 22.3 % M05: Seropositive rheumatoid arthritis, 77.7 % M06: Other rheumatoid arthritis). Only 21,616 insured patients (38.9 %) were prescribed a guideline-recommended conventional DMARD or biologic at least once within one year of/after the first diagnosis. Among incident patients, the coverage rate with disease-modifying drugs was below the prevalence patients (31.5 % vs. 42.1 %). 60.9 % of M05 patients and only 29.7 % of M06 patients received a single DMARD after index diagnosis. If a DMARD has been prescribed, then it was prescribed, on average, within the first quarter of the initial diagnosis. The leading role in the prescription of basic therapies for index medication is provided by the rheumatologist. Nevertheless, 68.3 % of patients consulted a specialist in rheumatology at least once within a year of the first diagnosis. CONCLUSION: The results of this large sample show differences in the guideline recommended prescription of disease-modifying drugs for different subgroups of RA as well as an undersupply in patients not treated by the rheumatologist.

Auguste Renoir, Sculptor With Hired Hands: A Masterful Artistic Cooperation Overshadowed by Legal Issues and Copyright Infringement.

The coping with rheumatoid arthritis of the famous French impressionist painter Pierre-Auguste Renoir (1841-1919) is described in former publications. The heavily handicapped painter has in his last years created sculptures in cooperation with the sculptor Richard Guino (1890-1973). The extraordinary genesis of the sculptures through a masterful artistic cooperation, as well as the resulting legal issues and shameful copyright infringements, is reported. Renoir's decision to create sculptures with the help of Guido can be attributed to his remarkable artistic vision, vitality, optimistic nature, and strong will and is also a further testimonial of creative coping of an artist overcoming the physical handicap due to rheumatoid arthritis of his final years, so far not described in detail in the medical literature.

Claims Data Analysis of Tumor Necrosis Factor Inhibitor Treatment Dosing Among Patients with Rheumatoid Arthritis: A Systematic Review of Methods.

BACKGROUND: With tumor necrosis factor inhibitors, changes of dosing, switching between drugs, insufficient adherence, and persistence are frequent in rheumatoid arthritis. Because this is often associated with decreased efficiency and increased costs, dosage analyses based on claims data are of increasing interest for healthcare providers and payers. Nevertheless, no standardized methods exist to ensure high-quality research. OBJECTIVE: In this review, we compare and discuss applied methods in claims data-based dosage analyses of tumor necrosis factor inhibitor prescriptions in patients with rheumatoid arthritis. METHODS: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The dosage analysis methods performed within the selected studies were classified into switching, persistence, adherence, and dosage-change analyses, and were then compared and finally discussed. RESULTS: A total of 45 studies were found to be relevant. In most studies, a change in dose or persistence was evaluated, followed by switching and adherence analyses. Analyses of changed dose exhibit the most extensive variation of methods. We divided them into three principal methods, where a specified reference dose is compared with (1) the last dose, (2) any dose, or (3) all doses. CONCLUSION: The systematic review identified a high variation of methods. Our results may be helpful for choosing appropriate methods in future studies. The results also demonstrate the need for evidence-based recommendations of methods used in claims data research.

Coinfection of Chlamydiae and other Bacteria in Reactive Arthritis and Spondyloarthritis: Need for Future Research.

Reactive (inflammatory) arthritis has been known for many years to follow genital infection with the intracellular bacterial pathogen Chlamydia trachomatis in some individuals. Recent studies from several groups have demonstrated that a related bacterium, the respiratory pathogen Chlamydia pneumoniae, can elicit a similar arthritis. Studies of these organisms, and of a set of gastrointestinal pathogens also associated with engendering inflammatory arthritis, have been relatively extensive. However, reports focusing on coinfections with these and/or other organisms, and the effects of such coinfections on the host immune and other systems, have been rare. In this article, we review the extant data regarding infections by multiple pathogens in the joint as they relate to engendering arthritis, and we suggest a number of research areas that must be given a high priority if we are to understand, and therefore to treat in an effective manner, such arthritides.

Causality of Chlamydiae in Arthritis and Spondyloarthritis: a Plea for Increased Translational Research.

Current molecular genetic understanding of the metabolically active persistent infection state of Chlamydia trachomatis and Chlamydia pneumoniae in the synovium in patients with arthritis and spondyloarthritis favors a causal relationship. Here, we examine how adequately the accepted criteria for that etiologic relationship are fulfilled, emphasizing the situation in which these microorganisms cannot be cultivated by standard or other means. We suggest that this unusual situation of causality by chlamydiae in rheumatic disease requires establishment of a consensus regarding microorganism-specific terminology as well as the development of new diagnostic and classification criteria. Recent studies demonstrate the value of molecular testing for diagnosis of reactive arthritis, undifferentiated spondyloarthritis, and undifferentiated arthritis caused by C. trachomatis and C. pneumoniae in clinical practice. Data regarding combination antibiotic therapy is consistent with the causative role of chlamydiae for these diseases. Observations of multiple intra-articular coinfections require more research to understand the implications and to respond to them.