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An acute attack of gouty arthritis is one of the most painful experiences reported throughout medical history. Therefore it is paramount to initiate appropriate therapy quickly in order to terminate the acute phase. This goal can be achieved with non‐steroidal anti‐inflammatory agents, colchicine, or corticosteroid‐based therapies. Rarely, because of contraindications to these agents, only symptomatic treatment can be given until the attack subsides. The next step is to lower the serum urate level below the limit of solubility (i.e., below 40.8 mmol/L, or 6.8mg/dL) which reduces recurrences and begins to return the total body urate pool to normal. This equally important goal can be achieved by uricosuric agents or xanthine oxidase inhibitors, although the latter is generally favored. Allopurinol is the agent most commonly preferred because of its safety profile and ease of use, but there are known serious allergic reactions and untoward side effects that occasionally require discontinuation. Febuxostat, a xanthine oxidase inhibitor, and pegylated uricase are new agents under development and may be beneficial in these situations or when other comorbid conditions prevent the use of conventional treatments. Alcohol and dietary consumption are also related to hyperuricemia and acute gout. Recently beer, wine, and liquor were studied and the risk of gout varied according to the alcohol ingested. Furthermore, recent data sheds light on important dietary modifications that may help in the treatment of gout, and dispels certain beliefs about protein ingestion and the occurrence of acute gout. As we learn more about the associated conditions of hypertriglyceridemia, hypertension, and the metabolic syndrome, it may allow the tailoring of medical regimens that directly prevent or reduce recurrent attacks of gouty arthritis. There are specific approved treatments for these common comorbidities that have parallel effects of lowering serum urate levels. These recent findings may be especially important for treating refractory cases. While patient education remains a cornerstone to ensure compliance, other quality indicators for the management of this disease have been reported and should guide the clinician in the treatment of gout and result in improved care. [ABSTRACT FROM AUTHOR]

One of the earliest described conditions, gout continues to plague humanity. It is characterised by the deposition of monosodium urate crystals in the joints and soft tissue. The main clinical features of gout are hyperuricaemia, acute monoarticular arthritis, tophi and chronic arthritis, along with nephrolithiasis. Gout typically occurs in middle age and more commonly in men. Asymptomatic hyperuricaemia does not require treatment. The initial attack of acute gout usually affects a single joint, often the first metatarsal phalangeal joint. Definitive diagnosis requires demonstration of urate crystals in the joint fluid. Treatment of acute gout includes nonsteroidal anti-inflammatory drugs (NSAIDs), colchicine and corticosteroids. The most important factor in success of treatment is how quickly therapy is begun after onset of symptoms. Drug treatment of hyperuricaemia includes allopurinol, sulfinpyrazone, probenecid and benzbromarone and should be used in patients with frequent gout attacks, tophi or urate nephropathy. [ABSTRACT FROM AUTHOR]

A prospective analysis of 60 patients with gout was undertaken to evaluate the radiographic spectrum of gouty arthritis in patients treated in the era of hypouricemic therapy. Twenty-two of these patients were clinically tophaceous; 36 were considered to have radiographic findings diagnostic of gouty arthritis by strict radiographic criteria. Up to 24% of the patients denied symptoms in joints with radiographic changes of gout; 42% with no evidence of tophi on clinical examination had radiographic changes characteristic of gout. Radiographic assessment can be extremely helpful in the management of gout by documenting the degree and extent of bony involvement, particularly in patients with limited symptoms or without clinical tophi. [ABSTRACT FROM AUTHOR]

A new class of photochromic glasses for use in irreversible holographic optical storage applications is described. The recording mechanism involves a triplet-sensitized photoreaction of an organic chromophore. The materials are isotropic and red-sensitive, and exhibit high diffraction efficiencies and long hologram lifetimes. The wavelength sensitivity can be adjusted by the choice of sensitizer; C60, sensitive in the red, is described here. Single digital data page recording and error-free readout are demonstrated at a density of 0.5 Mb/cm2; multiplexing in a 150-μm-thick sample is also demonstrated. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The title compound, 4-methoxy­pyridinium-3-squarate or 2-(4-methoxy­pyridinio)-3,4-dioxo­cyclo­but-1-en-1-olate, C10H7NO4, exhibits an interplanar angle of 5.3 (2)°. The bond lengths within the squarate system represent average values for the two possible resonance structures, with a central typical carbonyl bond [1.209 (3) Å] flanked by two longer `semi­carbonyl' bonds of length 1.230 (3) Å. [ABSTRACT FROM AUTHOR]

The article focuses on the crystallization of the compound 4-phenylpyridinium hydrogensquarate. In the crystal structure individual anions are linked into centrosymmetric dimers by strong hydrogen bonds. Alternating layers of 4-phenylpyridinium cations and hydrogensquarate anions are arranged along the axis. In the experiment a water-ethanol solution of 4-phenylpyridine was added to an aqueous solution of an equimolar quantity of squaric acid.

Recommends the use of analogies in educating patients on the effective management or treatment of gout. Aim to improve patient compliance and outcomes; Discrepancy between knowledge and treatment effectiveness; Determination of whether a patient's hyperuricemia is caused by urate overproduction or decreased excretion; Urate-lowering therapy with allopurinol.

Abstract: [18F]Fluoroethylcholine has been recently introduced as a promising 18F-labelled analogue of [11C]choline which had been previously described as a tracer for metabolic cancer imaging with positron emission tomography (PET). Due to the practical advantages of using the longer-lived radioisotope 18F (t 1/2 =110min), offering the opportunity of a more widespread clinical application, we established a reliable, fully automated synthesis for its production using a modified, commercially available module. [18F]Fluoroethylcholine was prepared from N,N-dimethylaminoethanol by iodide catalyzed alkylation with 1-[18F]fluoro-2-tosylethane as alkylating agent, resulting in a total radiochemical yield of 30±6% after a synthesis time of 50min. The specific activity of [18F]fluoroethylcholine was >55GBq/μmol and the radiochemical purity 95–99%. [Copyright &y& Elsevier]

Background: Intraocular lenses with a negative aspherical design for correction of corneal spherical aberration (SA) have gained popularity in recent decades. In most cases, a 'one size fits all' concept is followed, where all eyes receive lenses with the same SA correction. The purpose of this study is to develop a strategy based on raytracing using anterior segment tomography data to extract corneal SA and to provide simple multivariable linear models for prediction of corneal SA., Methods: The analysis was based on a large dataset of 8737 measurements of 8737 eyes from 1 clinical centre, using the Casia2 anterior segment tomographer. An optical model based on: corneal front and back surface radius Ra and Rp, asphericities Qa and Qp, corneal thickness CCT, anterior chamber depth ACD, and pupil centre position (X-Y position: Pup X and Pup Y ), was defined for each measurement. Corneal SA was derived using a 6-mm aperture perpendicular to the incident ray and centred on the chief ray, and linear prediction models were derived for SA using biometric data. Cross-validation was used for model performance evaluation., Results: Using raytracing, the wavefront error within an aperture (6-mm diameter centred on the intersection of the chief ray with the cornea) was calculated and corneal SA was extracted. After identifying the relevant effect sizes (Ra, Qa, Rp Qp, ACD, Pup X and Pup Y ) using stepwise linear regression, linear mixed-effects models (model 1: all effect sizes, model 2: Ra, Qa, Rp and Qp, model 3: Ra and Qa) were set up on the training data in terms of a Monte-Carlo simulation. On the test data (training data), model 1 with a mean absolute/root-mean-squared prediction error of 0.0095/0.0130 (0.0095/0.0127) performed similarly to model 2 with 0.0097/0.0131 (0.0096/0.0127), and both outperformed model3 with 0.0152/0.0197 (0.0148/0.0190)., Conclusion: Based on the Casia2 anterior segment tomographer, corneal SA could be derived using shape data (curvature and asphericities) of both corneal surfaces (model 2). This information could easily be used for selection of the appropriate negative aspherical lens design in cataract surgery., (© 2022 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

The idiopathic inflammatory myopathies (IIM) constitute a subset of autoimmune conditions primarily affecting muscle, along with many extra-muscular manifestations. Proximal muscle weakness is the dominant symptom in the IIM. In addition, many patients will have cutaneous manifestations, pulmonary manifestations, and arthritis. There is an increased incidence of malignancy with the IIM. Diagnostic tools beyond history and physical exam include serum muscle enzyme and autoantibody testing, magnetic resonance imaging (MRI) of the extremities, ultrasound, neurologic testing, and muscle biopsy. Several options for treatment are reviewed.

Nonsteroidal anti-inflammatory drugs are a class of analgesics that includes traditional nonselective and selective cyclooxygenase-2 inhibitors that block the biosynthesis of prostaglandins and thromboxane. Indomethacin is a nonsteroidal anti-inflammatory drug with potent antipyretic, analgesic, and anti-inflammatory activity that has been effectively used in the management of mild-to-moderate pain since the mid-1960s. It is commonly prescribed for the relief of acute gouty arthritis pain, but has demonstrated efficacy in the treatment of various other painful conditions. Numerous comparative studies have affirmed the clinical utility of indomethacin relative to other widely used analgesics. This review provides an historic overview of indomethacin and its efficacy compared with other commonly used analgesics, and discusses new indomethacin drug products.

To elucidate the dependence of the nonlinear optical (NLO) response on the conformation of triply branched derivatives, a new series of D-pi-A dendrimers has been synthesized. A combined approach of experiments (UV-vis and EOA measurements) and computational predictions (semiempirical and ab initio) was applied both on the dendrimers and on the corresponding single-strand chromophores. It has been shown that depending on the surrounding media the NLO activity of a flexible dendrimer can be very different. Two limiting cases are proposed: (i) the dendrimer resembles a solution of the corresponding single-strand chromophores with about 3-fold concentration, where the hyperpolarizability is the sum of the effect of three noninteracting single-strand subunits ("independent chromophores" limit); (ii) the dendrimers show nearly parallel or helical alignments of the single-strand subunits. Because of this change of conformation the NLO activity can be enhanced up to nine times the value of the "independent chromophores" limit and, thus, are more than a single strand chromophore. Conformers of dendrimers with interacting single-strand chromophores have been identified experimentally in nonpolar solutions by the EOA spectroscopy and possible structures have been revealed by numerical calculations, which could moreover show the tendency of the effects on the hyperpolarizability due to structural changes of the flexible dendritic architecture. Implications for future research developments are given to implement the "more than three times" concept.

A combined experimental (optical and electro-optical absorption measurements) and computational (ab initio RHF and DFT) approach has been used to investigate the molecular low- and high-T(g) photorefractive (PR) performances of neutral and zwitterionic heteroaromatic dipolar chromophores in terms of structural and solvent-polarity effects. We have found that the nature of the building units (donor, acceptor, and spacer) and the polarity of the surrounding medium strongly affect all the relevant ground-state and nonlinear optical properties involved in the PR activity, that is, the dipole moment, the polarizability anisotropy, and first hyperpolarizability of the electronic ground-state. The variation of these properties is in turn transferred to molecular low- and high-T(g) PR figures of merit. It is shown that PR molecular performance not only relies on a proper choice of structural components but varies by orders of magnitude as a function of the medium polarity, and this suggests that a combination of molecular design and host-matrix engineering is required for optimized performances of PR materials.

We synthesized a series of amino substituted triarylboranes (TABs) 1-3 by copper(I)-catalyzed cross-coupling reactions. The title compounds were investigated by means of cyclic voltammetry (CV) and UV-visible absorption and fluorescence spectroscopy. Electrochemical oxidation of tris(4-carbazolyl-2,6-dimethylphenyl)borane (3) leads to the formation of an electroactive polymer film on the electrode surface. The charge-transfer (CT) absorption band of all three TABs shows a pronounced negative solvatochromism, while the emission is positively solvatochromic. By combining Jortner's theory, AM1 computations, and electrooptical absorption measurements (EOAM), this unexpected behavior was shown to be due to a dipole inversion upon S0-->S1 excitation. Furthermore, polarized steady-state fluorescence spectroscopy and EOAM prove that the ground-state geometry of 3 is of lower symmetry than D3 and that the excitation energy can be transferred from one subchromophore to another within the lifetime of the excited state. Exciton-coupling theory was used to quantitatively analyze this excitation transfer.