A clinical practice guideline for the management of the foot and ankle in rheumatoid arthritis.

Rheumatoid arthritis causes progressive joint destruction in the long term, causing a deterioration of the foot and ankle. A clinical practice guideline has been created with the main objective of providing recommendations in the field of podiatry for the conservative management of rheumatoid arthritis. Thus, healthcare professionals involved in foot care of adults with rheumatoid arthritis will be able to follow practical recommendations.

Agreement Among Multiple Observers on Crystal Identification by Synovial Fluid Microscopy.

Objective: Despite the fact that polarized microscopy remains the gold standard for diagnosing crystal arthritis, some uncertainties hamper full implementation in clinical practice. We undertook this study to analyze the agreement among multiple observers in crystal identification using compensated polarized microscopy, as well as to assess potential outcome modifiers.

Methods: This was a cross-sectional, observational study with consecutive synovial fluid sampling.

Gouty Involvement of Foot and Ankle: Beyond Flares.

The foot and ankle are common locations of deposition of monosodium urate (MSU) crystals, as indicated by the clinical manifestations presented by patients with gout, which are not limited to the acute inflammation of the big toe. We present a narrative literature review aimed to update the gout involvement of foot and ankle and how it affects the quality of life. Cumulative reports indicate that gout, even at the non-tophaceous stage, could cause pain, gait impairment and limit the mobility at lower limbs.

Persistence of Crystals in Stored Synovial Fluid Samples.

Objective: Lack of access to polarized light microscopy is often cited as an argument to justify the clinical diagnosis of crystal-related arthritis. We assessed the influence of time since sampling and preservation methods on crystal identification in synovial fluid (SF) samples under polarized light microscopy.

Methods: This was a prospective, longitudinal, observational factorial study, analyzing 30 SF samples: 12 with monosodium urate (MSU) crystals and 18 with calcium pyrophosphate (CPP) crystals.

Cardiovascular risk of patients with gout seen at rheumatology clinics following a structured assessment.

Objectives: Gout-associated cardiovascular (CV) risk relates to comorbidities and crystal-led inflammation. The aim was to estimate the CV risk by prediction tools in new patients with gout and to assess whether ultrasonographic carotid changes are present in patients without high CV risk.

Methods: Cross-sectional study.

Gout: optimizing treatment to achieve a disease cure.

Gout is one of the most common inflammatory arthritides. The disease is due to the deposition of monosodium urate crystals. These deposits are reversible with proper treatment, suggesting that gout is a curable disease.

Primary tuberculosis infection in patients treated with tumor necrosis factor-alpha antagonists and a negative initial screening.

Introduction: Despite screening for latent tuberculosis (TB), new cases of TB infection are detected in patients treated with anti-TNF-α and negative initial screening, some of them after long treatment, which points more to a new infection.

Objectives: To describe the cases that have presumably developed a primary tuberculous infection during treatment with anti-TNF-α drugs.

Methods: Retrospective audit (1999-2012).

Single-channel study of the binding-gating coupling in the slowly desensitizing chimeric alpha7-5HT3A receptor.

We have studied the role of the highly conserved residue alphaLysine145 in the early steps of activation by acetylcholine of the nicotinic acetylcholine receptor (nAChR). Both macroscopic and single-channel currents were recorded in the slowly desensitizing chimeric mutant receptor alpha7V201-5HT3A/R432Q/R436D/R440A, made of alpha7 nAChRs and serotonin receptors of subtype 3A (ch1), and its corresponding mutant K145A (ch1/K145A) expressed in Xenopus oocytes. Mutant ch1/K145A receptors had a reduced gating function similar to that produced by the same mutation in the wild type receptor alpha7.

Binding-gating coupling in a nondesensitizing alpha7 nicotinic receptor A single channel pharmacological study.

The highly conserved alphaLys145 has been suggested to play an important role in the early steps of activation of the nicotinic acetylcholine receptor (nAChR) by acetylcholine. Both macroscopic and single channel currents were recorded in the slowly desensitizing mutants L248T- and K145A-L248T-alpha7 receptors expressed in Xenopus oocytes. On ACh-evoked currents, substitution of Lys145 by alanine showed the same effects that in wild type receptors: moderately decreased gating function and a more-than-expected loss of ACh potency, thus validating the experimental model.

Improved gating of a chimeric alpha7-5HT3A receptor upon mutations at the M2-M3 extracellular loop.

Acetylcholine-evoked currents of the receptor chimera alpha7-5HT3A V201 expressed in Xenopus oocytes are strikingly small when compared to the amount of alpha-bungarotoxin binding sites detected at the oocyte membrane. Since the chimeric receptor is made of the extracellular N-terminal region of the rat alpha7 nicotinic acetylcholine receptor and the C-terminal region of the mouse 5-HT3A receptor, which includes the ion channel, we hypothesized that communication between these two regions was not optimal. Here, we show that mutating to aspartate several adjacent positions in the M2-M3 extracellular linker increases current amplitudes to different extents, thus confirming the important role of this region on receptor gating.

Potentiation of human alpha4beta2 neuronal nicotinic receptors by a Flustra foliacea metabolite.

The effects of various Flustra foliacea metabolites on different types of human neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes were investigated. Whereas most of the compounds tested had a small blocking effect, one of them, deformylflustrabromine, selectively increased the current obtained in alpha4beta2 receptors when co-applied with acetylcholine (ACh). The current increase was reversible and concentration-dependent.