Ligand Binding to Chlorite Dismutase from Magnetospirillum sp.

Chlorite dismutase (Cld) catalyzes the reduction of chlorite to chloride and dioxygen. Here, the ligand binding to Cld of Magnetospirillum sp. (MaCld) is investigated with X-ray crystallography and electron paramagnetic resonance (EPR).

Aromatic aldehydes at the active site of aldehyde oxidoreductase from Desulfovibrio gigas: reactivity and molecular details of the enzyme-substrate and enzyme-product interaction.

Desulfovibrio gigas aldehyde oxidoreductase (DgAOR) is a mononuclear molybdenum-containing enzyme from the xanthine oxidase (XO) family, a group of enzymes capable of catalyzing the oxidative hydroxylation of aldehydes and heterocyclic compounds. The kinetic studies reported in this work showed that DgAOR catalyzes the oxidative hydroxylation of aromatic aldehydes, but not heterocyclic compounds. NMR spectroscopy studies using (13)C-labeled benzaldehyde confirmed that DgAOR catalyzes the conversion of aldehydes to the respective carboxylic acids.

Subcutaneous abscess secondary to xanthogranulomatous cholecystitis.

One of the known complications of gallstones consists in gallbladder perforation with cholecystocutaneous abscesses or external fistulas formation. Nowadays these types of complications are uncommon, having been more frequent. The authors report the case of an 86 year-old woman, bedridden and dependent, referred to our institution by presenting a tumefaction with inflammatory signs in the right upper quadrant.

Kinetic and structural studies of aldehyde oxidoreductase from Desulfovibrio gigas reveal a dithiolene-based chemistry for enzyme activation and inhibition by H(2)O(2).

Mononuclear Mo-containing enzymes of the xanthine oxidase (XO) family catalyze the oxidative hydroxylation of aldehydes and heterocyclic compounds. The molybdenum active site shows a distorted square-pyramidal geometry in which two ligands, a hydroxyl/water molecule (the catalytic labile site) and a sulfido ligand, have been shown to be essential for catalysis. The XO family member aldehyde oxidoreductase from Desulfovibrio gigas (DgAOR) is an exception as presents in its catalytically competent form an equatorial oxo ligand instead of the sulfido ligand.

Conventional videodefecography: Pathologic findings according to gender and age.

Objectives: To review the most common disorders depicted with conventional videodefecography, and to compare the defecographic abnormalities between symptomatic patients according to their gender and age.

Methods: Conventional videodefecography studies of 300 patients (24 men, 266 women; mean age - 57.7) performed in a 32-month period were reviewed for the following parameters: anorectal angle, movement of the pelvic floor, intussusceptions, incontinence and rectocele.

[Clot burden score in the evaluation of right ventricular dysfunction in acute pulmonary embolism: quantifying the cause and clarifying the consequences].

Introduction: Pulmonary angiography by computed tomography (CT) is the method of choice for the detection of acute pulmonary embolism (PE). Studies have shown that the severity of PE can be estimated by clot burden scores.

Objective: To evaluate the correlation between an angiographic clot burden score (Qanadli score - QS) and parameters of right ventricular dysfunction (RVD) in patients admitted for PE.

Impact of chronic kidney disease on the natural history of alkaptonuria.

In alkaptonuria, deficiency of homogentisate 1,2-dioxygenase leads to the accumulation of homogentisic acid (HGA) and its metabolites in the body, resulting in ochronosis. Reports of patients with alkaptonuria who have decreased kidney function are rare, but this seems to play an important role in the natural history of the disease. We describe a 68-year-old female with chronic kidney disease (CKD) of unknown etiology who started peritoneal dialysis (PD) after 5 years of follow-up and who was diagnosed with alkaptonuria at this time.

Delayed lead perforation: a rare cause of pacemaker dysfunction.

A 65-year-old woman with a dual-chamber pacemaker implanted in 2006 for symptomatic carotid sinus hypersensitivity was incidentally found to have loss of ventricular capture on routine pacemaker interrogation. A chest X-ray raised the suspicion of perforation and migration of the right ventricular lead, confirmed by three-dimensional echocardiogram and CT scan. On the basis of this case, we review myocardial lead perforation, including predisposing factors, pathophysiological mechanisms, diagnostic approach and therapeutic options.

[Computed tomographic angiography in the evaluation of acute pulmonary thromboembolism].

Computed tomographic andiography has becoming the main diagnostic imaging method for the evaluation of patients with suspected pulmonary embolism (PE), due to its high sensitivity and specificity and potential cost-effectiveness. The advances in multidetector computed tomography (MDCT) scanners and optimization of scanning protocols via thinner collimation and faster scanning times have greatly improved the ability to detect PE. The diagnosis is made by direct visualization of a low attenuation filling defect (intraluminal thrombus) that partially or completely occludes a contrast filled artery.