Brimonidine-LAPONITE® intravitreal formulation has an ocular hypotensive and neuroprotective effect throughout 6 months of follow-up in a glaucoma animal model

Intravitreal administration is widely used in ophthalmological practice to maintain therapeutic drug levels near the neuroretina and because drug delivery systems are necessary to avoid reinjections and sight-threatening side effects. However, currently there is no intravitreal treatment for glaucoma. The brimonidine-LAPONITE® formulation was created with the aim of treating glaucoma for extended periods with a single intravitreal injection. Glaucoma was induced by producing ocular hypertension in two rat cohorts: [BRI-LAP] and [non-bri], with and without treatment, respectively. Eyes treated with brimonidine-LAPONITE® showed lower ocular pressure levels up to week 8 (p < 0.001), functional neuroprotection explored by scotopic and photopic negative response electroretinography (p = 0.042), and structural protection of the retina, retinal nerve fibre layer and ganglion cell layer (p = 0.038), especially on the superior-inferior axis explored by optical coherence tomography, which was corroborated by a higher retinal ganglion cell count (p = 0.040) using immunohistochemistry (Brn3a antibody) up to the end of the study (week 24). Furthermore, delayed neuroprotection was detected in the contralateral eye. Brimonidine was detected in treated rat eyes for up to 6 months. Brimonidine-LAPONITE® seems to be a potential sustained-delivery intravitreal drug for glaucoma treatment.

Preparation and characterization of activated montmorillonite clay supported 11-molybdo-vanado-phosphoric acid for cyclohexene oxidation

Heterogenization of homogenous catalysts consisting of vanadium substituted polyphosphomolybdate with Keggin structure supported on activated bentonite for epoxidation of cyclohexene.

Correction: Preparation and characterization of activated montmorillonite clay supported 11-molybdo-vanado-phosphoric acid for cyclohexene oxidation

Correction for ‘Preparation and characterization of activated montmorillonite clay supported 11-molybdo-vanado-phosphoric acid for cyclohexene oxidation’ by S. Boudjema et al., RSC Adv., 2015, 5, 6853–6863.

Deubiquitinases in cancer: new functions and therapeutic options

Deubiquitinases (DUBs) have fundamental roles in the ubiquitin system through their ability to specifically deconjugate ubiquitin from targeted proteins. The human genome encodes at least 98 DUBs, which can be grouped into 6 families, reflecting the need for specificity in their function. The activity of these enzymes affects the turnover rate, activation, recycling and localization of multiple proteins, which in turn is essential for cell homeostasis, protein stability and a wide range of signaling pathways. Consistent with this, altered DUB function has been related to several diseases, including cancer. Thus, multiple DUBs have been classified as oncogenes or tumor suppressors because of their regulatory functions on the activity of other proteins involved in tumor development. Therefore, recent studies have focused on pharmacological intervention on DUB activity as a rationale to search for novel anticancer drugs. This strategy may benefit from our current knowledge of the physiological regulatory mechanisms of these enzymes and the fact that growth of several tumors depends on the normal activity of certain DUBs. Further understanding of these processes may provide answers to multiple remaining questions on DUB functions and lead to the development of DUB-targeting strategies to expand the repertoire of molecular therapies against cancer.

Metabolic syndrome characteristics in gout patients

Gout is commonly associated with obesity, arterial hypertension, diabetes, and dyslipidemia. However, the prevalence of metabolic syndrome has not been widely recognized in patients with gout. We studied 41 patients (37 males) with primary gout to assess the prevalence and characteristics of the associated metabolic syndrome. Twenty-one patients with gout (51%) showed >or=3 criteria for the metabolic syndrome. Pathological conditions associated were obesity (21/41), high blood pressure (30/41), dyslipidemia (30/41), and fasting plasma glucose >or= 100 mg/dL (22/41). The most frequent triad was the presence of increased waist circumference, elevated fasting plasma glucose, and hypertension. Mean serum urate concentration did not differ significantly in gout patients with the metabolic syndrome (8.5 mg/dl) and without (8.1 mg/dl). Given the complications associated with metabolic syndrome, its diagnosis may determine the long-term treatment of patients with gout.

Uric acid metabolism in patients with primary gout and the metabolic syndrome

Forty-four patients (40 males) with a mean age of 58 years were included in this pilot study. Mean serum urate concentration in patients with and without the metabolic syndrome (MS) was 8.8 mg/dL and 8.1 mg/dL, respectively. Urinary uric acid excretion was 543 mg/day/1.73 m(2) in the former and 609 mg/day/1.73 m(2) in the latter. Uric acid to creatinine ratio was 0.37 mg/mg in patients with the MS and 0.42 mg/mg in those without the MS. Mean serum urate increased from 8.6 mg/dL in subjects with three or more MS components to 10.3 mg/dL in those with five MS components. Serum urate was markedly lower in patients with mild MS (9 patients, 8.6 mg/dL) as compared to severe MS (10 patients, 9.2 mg/dL). In contrast, urinary uric acid to creatinine ratio was 0.42 mg/mg in patients with gout and mild MS and 0.33 mg/mg in gout patients with severe MS. Uric acid underexcretion appears to be more severe in gout patients with the MS. This disturbance appears to be related to the severity of the MS.

Serum urate, metabolic syndrome, and cardiovascular risk factors. A population-based study

We studied the associations between serum urate levels (determined in 503 subjects from a population of 1,344 subjects living in northern Madrid) and both the metabolic syndrome (MS) (defined by the Adult Treatment Panel III criteria) and C-reactive protein (CRP, determined in 382 subjects). MS was diagnosed in 25% (95%CI, 21-28%) and was associated with hyperuricemia (p<0.001). There was a graded increase in serum urate levels with increasing number of MS components. Urate concentrations significantly correlated with waist circumference (r=0,455, p<0.01). Serum urate was not independently associated with CRP levels. This study shows that serum urate levels are associated with the presence of MS and each of its features.

An unusual patient with hypothyroidism, tophaceous gout, and marked joint destruction

This report describes a 75-year-old Caucasian man with extensive urate deposits and severe gouty arthropathy that confined him to a wheelchair. Since age 50, he suffered multiple acute gout flares and progressive deformities in his hands, feet, knees, and elbows (tophi). Serum creatinine was 1.4 mg/dL and serum urate 9.4 mg/dL. Conditions known to increase uric acid production (psoriasis, chronic bronchitis) and to decrease uric acid excretion (hypothyroidism, metabolic syndrome, and nephroangiosclerosis) may operate in a single patient, illustrating the dramatic clinical course of untreated gout.

Improvement of ligand economy controlled by polymer morphology: the case of polymer-supported bis(oxazoline) catalysts

A functionalized chiral bis(oxazoline) is used as a chiral monomer in polymerization reactions leading to homo- and copolymers of different morphology. Polymers with a high content of chiral monomer lead to enantioselectivities that are higher than those obtained with the soluble ligand, but the chiral ligand is not used in an optimal way. A hyperbranched polymer, obtained by using a hexavinyldendrimer as the cross-linker, leads to the same enantioselectivities with a more efficient use of the chiral ligand.

Bis(oxazoline)copper complexes covalently bonded to insoluble support as catalysts in cyclopropanation reactions

Chiral bis(oxazolines) are readily dialkylated in the methylene bridge, opening the way to immobilization at that position, keeping the C(2) symmetry of the chiral ligand. Bis(oxazolines) functionalized with two allyl or vinylbenzyl groups are easily grafted onto mercaptopropylsilica. Another approach to immobilization is the polymerization of the ligands bearing vinylbenzyl groups to yield insoluble polymers. The Cu(OTf)(2) complexes of the immobilized ligands promote the enantioselective cyclopropanation reaction between styrene and ethyl diazoacetate. The results depend on the nature of the support and the method of immobilization. With regard to the type of solid, the best results, which are similar to or even better than those obtained with the corresponding dibenzylated homogeneous catalysts, are obtained with homopolymers. With regard to the bis(oxazoline), that bearing indan groups leads to good results both onto silica and polymers, whereas with the ligand bearing tert-butyl groups good enantioselectivities are only obtained with homopolymeric catalysts. Some of the heterogeneous catalysts can be easily recovered and reused, as much as five times, with the same yield and stereoselectivities.

Theoretical (DFT) insights into the mechanism of copper-catalyzed cyclopropanation reactions. Implications for enantioselective catalysis

The mechanism of the copper(I)-catalyzed cyclopropanation reaction has been extensively investigated for a medium-size reaction model by means of B3LYP/6-31G(d) calculations. The starting ethylene complex of the N,N'-dimethylmalonaldiimine--copper (I) catalyst undergoes a ligand exchange with methyl diazoacetate to yield a reaction intermediate, which subsequently undergoes nitrogen extrusion to generate a copper--carbene complex. The cyclopropanation step takes place through a direct carbene insertion of the metal--carbene species to yield a catalyst--product complex, which can finally regenerate the starting complex. The stereochemical predictions of a more realistic model (by considering a chiral bis(oxazoline)--copper (I) catalyst) have been rationalized in terms of steric repulsions, showing good agreement with experimental data.

[HELLP syndrome. Analysis of 2 cases]

HELLP syndrome (Hemolysis, Elevated Liver Enzymes, Low Platelets), one of the gestational diseases of the third trimester of pregnancy associated to eclampsia or preeclampsia, has a varied clinical expression, that include poor symptomatic patterns with malaise and/or dyspepsia, even several patterns with fatal outcome. We show two cases with clinical and laboratory criterion of HELLP syndrome, but with different clinical presentations. It's analyzed the pathogenicity, clinical-pathological expression, course and therapeutics options in HELLP syndrome.

[Chronic cholestasis as a presentation form of portal cavernoma]

A 37 year-old-woman was evaluated in 1993 for a chronic asymptomatic cholestasis. An endoscopic retrograde cholangiopancreatography showed the biliary tract compressed, and a mesenteric angiogram disclosed that the cause of biliary obstruction was a portal cavernoma. In addition, large esophageal varices with "red spots" were observed at endoscopy. Propranolol and ursodeoxicolic acid were started and the patient has remained asymptomatic to date. The biliary features of portal cavernoma are reviewed, as well as its pathogenesis, diagnosis and management. Portal cavernoma should be considered in the differential diagnosis of chronic cholestasis.

Transjugular intrahepatic portosystemic shunt for the management of hepatic hydrothorax in the absence of ascites

Hepatic hydrothorax in the absence of clinical ascites (HHAA) is a somewhat rare complication in decompensated cirrhosis. Patients with HHAA have a congenital defect in the tendinous portion of the diaphragm allowing rapid leakage of ascites into pleural cavity because of the cyclical negative intrathoracic pressure. Although several therapeutic approaches, including peritoneovenous shunt and chemical or surgical pleurodesis, have been attempted in these patients the results are largely unsatisfactory. A poor-risk surgical cirrhotic woman who was also considered not suitable for liver transplantation underwent transjugular intrahepatic portosystemic shunt (TIPS) for palliation of HHAA. After TIPS procedure hydrothorax completely resolved. TIPS can offer an attractive alternative to standard therapy in cirrhotic patients with HHAA.

[Chronic asymptomatic intrahepatic cholestasis associated with Turner's syndrome]

Turner syndrome or the gonadal dysgenesis syndrome which is monosomic because of the lack of an X chromosome (45 X) is associated to a greater incidence of autoimmune, particularly thyroidal, disorders and inflammatory intestinal disease, but is rarely associated to hepatic disorders. A female patient with chronic asymptomatic intrahepatic cholestasis which, to our knowledge, is the first reported in Spain, is herein presented. The 40-year old patient with a 45 X karyotype, feminine phenotype was accidently found to have a chronic alteration in the hepatic profile. Hepatic biochemical tests revealed AST 59 U/L, ALT 90 U/L, GGT 201 U/L and alkaline phosphatase 320 U/L. Hepatic echography was normal. Percutaneous liver biopsy was performed demonstrating minimum changes consisting of sinusoidal dilatation and pigment accumulation in the hepatocyte biliary pole. Treatment with ursodeoxycholic acid 15 mg/kg/day was administered showing a marked decrease in the laboratory parameters during follow up. Different hypothesis which may explain the association between chronic asymptomatic intrahepatic cholestasis and Turner syndrome are discussed.

Endogenous digoxin-like substance in liver failure

Digoxin-like immunoreactive substance (DLIS) has been detected in several patient populations that were not receiving digoxin. We therefore studied the sensitivity of EMIT Convenience Pack Digoxin immunoassay to interference by DLIS in patients with liver failure. Serum digoxin was measured in cirrhotic patients with moderate to severe liver failure (Child-Pugh B or C grade), patients with mild liver disease (chronic hepatitis) and matched control patients without liver disease. Excluded were patients taking or who had ever received any cardiac glycoside in the past. Blood samples were obtained by venipuncture and assayed in duplicate. Twenty-two out of 30 cirrhotic patients (73%) showed false-positive results, vs. one of 6 patients (16.7%) with mild liver disease, and 1 of 10 (10%) controls. The serum DLIS level was negatively correlated with prothrombin activity (r = -0.55, p < 0.00011). Digoxin levels must be interpreted carefully in patients with moderate to severe liver failure.