Optimization of electrodeposition parameters to improve composite hardness of nickel coatings on brass substrate for varying film thicknesses and applied indentation loads

In this investigation, nickel coatings were electrodeposited on brass substrate. The effects of electrodeposition process parameters such as, current density and deposition time (coatings thickness), on surface morphology and composite hardness values were studied. The value of the measured composite hardness by Vickers microindentation technique of the selected “hard film on soft substrate” composite system type depends on the applied indentation loads. For this reason, the microindentation loads are also included in the analysis. According to the experiment plan obtained by Design-Expert software, nickel coating has been produced on the brass cathode using galvanostatic regime (DC) with magnetic stirring of the electrolyte. The nickel sulphamate electrolyte with saccharine additive was used for Ni electrodeposition. Then, response surface methodology (RSM) was used to establish an adequate mathematical model. Subsequently, a mathematical model was developed to weight the effects of each input parameters (coating thickness, current density and indentation load) on the output parameter (composite hardness) of electrodeposited nickel coatings on brass substrate. According to the obtained results, the coating thickness and indentation load greatly influenced resulting composite hardness. On the other hand, coating current density primarily influenced microstructure and surface roughness. The topographic modification of the Ni coating surface depending on the post-treatment (mechanical and chemical) after deposition was studied using AFM microscopy

EULAR Points to Consider for the use of imaging to guide interventional procedures in patients with rheumatic and musculoskeletal diseases (RMDs)

OBJECTIVES: To develop evidence-based Points to Consider (PtC) for the use of imaging modalities to guide interventional procedures in patients with rheumatic and musculoskeletal diseases (RMDs). METHODS: European Alliance of Associations for Rheumatology (EULAR) standardised operating procedures were followed. A systematic literature review was conducted to retrieve data on the role of imaging modalities including ultrasound (US), fluoroscopy, MRI, CT and fusion imaging to guide interventional procedures. Based on evidence and expert opinion, the task force (25 participants consisting of physicians, healthcare professionals and patients from 11 countries) developed PtC, with consensus obtained through voting. The final level of agreement was provided anonymously. RESULTS: A total of three overarching principles and six specific PtC were formulated. The task force recommends preference of imaging over palpation to guide targeted interventional procedures at peripheral joints, periarticular musculoskeletal structures, nerves and the spine. While US is the favoured imaging technique for peripheral joints and nerves, the choice of the imaging method for the spine and sacroiliac joints has to be individualised according to the target, procedure, expertise, availability and radiation exposure. All imaging guided interventions should be performed by a trained specialist using appropriate operational procedures, settings and assistance by technical personnel. CONCLUSION: These are the first EULAR PtC to provide guidance on the role of imaging to guide interventional procedures in patients with RMDs

Discovertebral (Andersson) lesions in severe ankylosing spondylitis: a study using MRI and conventional radiography

The objective of this study is to investigate the prevalence of Andersson lesions (AL) in ankylosing spondylitis (AS) patients who will start anti-tumor necrosis factor (TNF) treatment. Radiographs and magnetic resonance imaging (MRI) of the spine were performed before therapy with anti-TNF. ALs were defined as discovertebral endplate destructions on MRI, associated with bone marrow edema and fat replacement or sclerosis, a decreased signal on T1, enhancement after contrast administration (gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA)), and increased signal on T2 and short tau inversion recovery (STIR). Additionally, conventional radiography showed a fracture line, irregular endplates, and increased sclerosis of adjacent vertebral bodies. Fifty-six AS patients were included, 68% males, mean age of 43 years, and mean disease duration of 11 years. The mean bath ankylosing spondylitis disease activity index was 6.4, and 24% of all patients had ankylosis. Only one patient showed a discovertebral abnormality with bone marrow edema of more than 50% of the vertebral bodies adjacent to the intervertebral disk of T7/T8 and T9/T10, a hypodense signal area on T1, and a high signal on STIR. Irregular endplates were depicted, and T1 after Gd-DTPA demonstrated high signal intensity around the disk margins. However, no fracture line was visible on conventional radiology, and therefore, this case was not considered to be an AL. No AL was detected in our AS patients, who were candidates for anti-TNF treatment. One patient showed a discovertebral abnormality on MRI, without a fracture line on conventional radiology. The relative small proportion of patients with a long-established disease might explain this finding for, particularly, an ankylosed spine is prone to develop an AL

Discovertebral (Andersson) lesions of the spine in ankylosing spondylitis revisited

A well-known complication in patients with ankylosing spondylitis (AS) is the development of localised vertebral or discovertebral lesions of the spine, which was first described by Andersson in 1937. Since then, many different terms are used in literature to refer to these localised lesions of the spine, including the eponym ‘Andersson lesion’ (AL). The use of different terms reflects an ongoing debate on the exact aetiology of the AL. In the current study, we performed an extensive review of the literature in order to align communication on aetiology, diagnosis and management between treating physicians. AL may result from inflammation or (stress-) fractures of the complete ankylosed spine. There is no evidence for an infectious origin. Regardless of the exact aetiology, a final common pathway exists, in which mechanical stresses prevent the lesion from fusion and provoke the development of pseudarthrosis. The diagnosis of AL is established on conventional radiography, but computed tomography and magnetic resonance imaging both provide additional information. There is no indication for a diagnostic biopsy. Surgical instrumentation and fusion is considered the principle management in symptomatic AL that fails to resolve from a conservative treatment. We advise to use the term Andersson lesion for these spinal lesions in patients with AS

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Use of buffered formaldehyde in the enzymatic digestion of inflamed mucosa.

Mucosal inflammation is associated with altered expression of cell membrane molecules. Disaggregation of tissue for flow cytometry may introduce artefactual changes. In an attempt to prevent the induction of artefacts, cells were fixed prior to isolation. The addition of 0.1% buffered formaldehyde to the collagenase/dispase digestion of mucosal biopsy specimens from patients with inflammatory bowel disease enhances detection of CD3, CD11b, CD16, CD63, and CD14. No significant effect was noted for CD19, CD67 or CD45. The expression of CD3, CD11b and CD45 correlated with the degree of endoscopic inflammation. Dilute buffered formaldehyde may be a useful adjunct to the enzymatic isolation of cells from mucosal specimens, by protecting surface antigens from digestion or alterations in expression

Inflammatory bowel disease is associated with increased mucosal levels of bactericidal/permeability-increasing protein

Clinical sepsis seldom accompanies inflammatory bowel disease. The aim of this study was to measure colonic mucosal levels of the neutrophil product bactericidal/permeability-increasing protein (BPI), which kills gram-negative bacteria in addition to inactivating endotoxin. Enzyme-linked immunosorbent assay and immunohistochemistry for BPI were performed on homogenates and tissue secretions of biopsy specimens from patients with ulcerative colitis (n=11) and Crohn's disease (n=5) and from normal controls (n=5). Mucosal neutrophil content (144 +/- 23 vs. 35 +/- 9 neutrophils/mg protein; P <0.007) and BPI content (2.07 +/- 0.75 vs. 0.12 +/- 0.02 ng/mg protein; P <0.002) were greater in the colitis groups and correlated closely (r=0.68; P <0.001). This relationship held for both ulcerative colitis (P <0.002) and Crohn's disease (P <0.01) with a trend towards greater levels in Crohn's disease. There was a trend towards higher BPI levels with an increasing endoscopic inflammation score (grade I, 1.32 +/- 0.6 ng/mg protein; grade II, 2.82 +/- 1.4 ng/mg protein). Immunohistochemistry and the biopsy culture showed BPI to be both intracellular and extracellular, to be present in the crypt lumen, and to be released into incubating medium. Mucosal levels of BPI are increased in colitis. Such localization may ameliorate mucosal responses to gram-negative bacteria and their product