Initial purification of N-acetylgalactosamine-4-sulphate sulphatase from human liver homogenates containing approx. 1 mg of enzyme in 26 g of soluble proteins was achieved by a six-column chromatography procedure and yielded approx. 40 micrograms of a single major protein species. Enzyme thus prepared was used to produce N-acetylgalactosamine-4-sulphate sulphatase-specific monoclonal antibodies. The use of a monoclonal antibody linked to a solid support facilitated the purification of approx. 0.5 mg of N-acetylgalactosamine-4-sulphate sulphatase from a similar liver homogenate. Moreover the enzyme isolated contained a single protein species, shown by SDS/polyacrylamide-gel electrophoresis to have an Mr of 57,000, which dissociated into subunits of Mr 43,000 and 13,000 in the presence of reducing agents. Essentially identical enzyme preparations were isolated from homogenates of human kidney and lung and from concentrated human urine. The native protein Mr of enzyme from human liver and kidney was assessed by gel-permeation chromatography to be 43,000 on Ultrogel AcA and Bio-Gel P-150. The liver N-acetylgalactosamine-4-sulphate sulphatase was shown to have pH optima of approx. 4 and 5.5 with the oligosaccharide substrate (GalNAc4S-GlcA-GalitolNAc4S) and fluorogenic substrate (methylumbelliferyl sulphate) respectively. Km values of 60 microM and 4 mM and Vmax. values of 2 and 20 mumol/min per mg were determined with the oligosaccharide and fluorogenic substrates respectively.
Human α‐L iduronidase from liver was purified about 20 000‐fold with a new rapid three‐step, five‐column procedure which consisted of a Concanavalin‐A–Sepharose/Blue‐A–Agarose coupled step, a CM‐Sepharose/Bio‐Gel HT coupled step followedby a cupric‐ion‐chelating Sepharose 6B step. The behaviour of α‐L‐iduronidase on gel permeation chromatography was dependent upon both pH and ionic strength of the eluting buffer. The formation of species with enzyme activity which behaved as large‐molecular‐mass aggregates was favoured under conditions of low ionic strength and neutral pH. The amount of high‐Mr species diminished as the pH decreased or the ionic strength increased to favour a single active species of Mr 65000. A specific monoclonal antibody was generated against liver α‐L‐iduronidase. The antibody specifically immunoprecipitated enzyme activity from both crude and purified sources. The subunit Mr of liver α‐L‐iduronidase was estimated to be 65000 using SDS‐PAGE. Monoclonal antibody immunoprecipitation of radiolabelled enzyme was used to provide definitive confirmation of this subunit size.
The kinetic parameters (Km and V) of human arylsulphatase B (4-sulpho-N-acetylgalactosamine sulphatase) activity in cultured skin fibroblasts were determined with a variety of substrates matching structural aspects of the physiological substrates in vivo chondroitin 4-sulphate and dermatan sulphate. More structurally complex substrates, in which several aspects of the aglycone structure of the natural substrate were maintained, were desulphated up to 4400 times faster than the minimum arylsulphatase-B-specific substrate, namely the monosaccharide N-acetylgalactosamine 4-sulphate. Aglycone structures that influence substrate binding and/or enzyme activity were an adjacent-residue C-6 carboxy group and a second but internal N-acetylgalactosamine 4-sulphate residue. Arylsulphatase B activity in fibroblast homogenates assayed with O-(beta-N-acetylgalactosamine 4-sulphate)-(1----4)-O-D-(beta-glucuronic acid)-(1----3)-O-D-N-acetyl[1-3H] galactosaminitol 4-sulphate derived from chondroitin 4-sulphate as substrate clearly distinguished Maroteaux-Lamy-syndrome patients from normal controls and other mucopolysaccharidosis patients. We recommend the use of the above trisaccharide substrate for both postnatal and prenatal diagnosis of Maroteaux-Lamy syndrome.
PFR is a physical therapy that should be considered as the initial treatment in patients with fecal incontinence. An improvement can be expected in up to 67 percent of patients. Initial good results can predict overall outcome.
Increasing evidence suggests that motility disorders of the sphincter of Oddi may lead to episodes of recurrent pancreatitis in a small proportion of patients with the diagnosis of idiopathic recurrent pancreatitis. Over 10 years, 35 patients have been identified and treated for this condition. The aim of the study was to assess symptomatic outcome in these patients. Following the exclusion of common causes of pancreatitis the patients underwent sphincter of Oddi manometry. Patients with manometric abnormalities and three with normal manometric findings underwent treatment. Twenty-six patients with persistent symptoms underwent total division of the sphincter via open sphincteroplasty and septectomy. Patients were followed up according to symptoms and classed as having a cure, mild symptoms or no change. At a median follow-up of 24 (range 9-105) months, 15 of the 26 patients were cured, eight had only mild symptoms and three remained unchanged. In the majority of patients with a good clinical outcome, manometry had demonstrated sphincter of Oddi stenosis. Total division of the sphincter of Oddi is associated with good symptomatic outcome in patients with recurrent episodes of pancreatitis and documented sphincter of Oddi stenosis.
Introduction: Sphincter of Oddi (SO) manometry is at present the "gold standard" investigation for patients with suspected biliary SO dysfunction. Non-invasive scintigraphy in cholecystectomised patients using a complex scoring system or the transit time from the hepatic hilum to the duodenum (HDTT) have been promoted as sensitive and specific alternatives. Aim: To evaluate the scintigraphic scoring system and HDTT in patients with suspected biliary SO dysfunction undergoing SO manometry. Methods: Cholecystectomised patients undergoing SO manometry for persistent biliary-type pain, as defined by the Rome II criteria, for which all other causes had been excluded, were prospectively studied. Scintigraphy with cholecystokinin octapeptide infusion was performed within a month prior to manometry. Scoring of the scans and measurement of HDTT was performed by independent blinded observers. Manometry of the biliary sphincter was performed per-endoscopically and defined as abnormal if basal pressure was > 40 mm Hg. Results: Thirty two patients were enrolled (30 females, mean age 45.1 years). Three patients were excluded from analysis because manometry from the bile duct was not technically possible. Eight patients had abnormal manometry. Scintigraphic scoring had a sensitivity of 25-38%, a specificity of 86-89%, positive predictive value (PPV) of 40-60%, and a negative predictive value (NPV) of 75-79%. The coefficient of variation for interobserver variation in scores was 0.72. HDTT sensitivity was 13%, specificity 95%, PPV 50%, and NPV 74%. Conclusions: Our findings indicate that scintigraphy using these methods of analysis correlates poorly with manometry in post cholecystectomy patients with suspected biliary SO dysfunction.
The pathophysiology of choledochal cysts remains unclear, although an association with anomalous pancreato-biliary junction and the reflux of pancreatic enzymes into the biliary tree is known. Sphincter of Oddi (SO) manometry was performed in three patients with choledochal cysts. All patients exhibited an elevated basal pressure diagnostic of sphincter of Oddi dysfunction. Two patients exhibited anomalous pancreato-biliary junction. This report suggests an association between the choledochal cyst and sphincter of Oddi dysfunction, and may suggest that SO dysfunction plays a role in choledochal cyst formation.
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