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Biomedical subjects

N Ahsan

Publications and source records attributed to N Ahsan.

44 records · Page 3Linked to original sources
PubMed1993

Evaluation of liquid yeast-derived sucrase enzyme replacement in patients with sucrase-isomaltase deficiency.

BACKGROUND: No enzyme replacement therapy exists for patients with congenital sucrase-isomaltase deficiency (CSID). A by-product of the manufacture of baker's yeast is a liquid preparation containing high sucrase activity. The aim of the present study was to investigate the activity and stability of this preparation and its effect on breath hydrogen excretion and gastrointestinal symptoms after sucrose ingestion in 14 patients with CSID. METHODS: The homogeneity of yeast sucrase was studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its activity was measured. Stability at various temperatures and pH ranges and in the presence of gastric aspirate, pepsin, and bovine serum albumin was assessed. Fourteen patients with CSID underwent double-blind placebo-controlled breath tests with yeast sucrase. They then completed an 8-week dose response study that used different enzyme concentrations while consuming a sucrose-containing diet. RESULTS: Liquid yeast sucrase is highly glycosylated, contains no lactase activity, and is stable at 4 degrees C and over a wide range of pH. Pepsin digestion of the enzyme in vitro can be blunted by bovine serum albumin and by increasing the pH. Yeast sucrase reduces breath hydrogen excretion in patients with CSID who are given a sucrose load (P < 0.001) and allows most patients to consume a sucrose-containing diet. CONCLUSIONS: Liquid yeast sucrase offers effective enzyme replacement therapy for patients with CSID.

Administration, Oral↗
PubMed1990

Retroperitoneal fibrosis.

Retroperitoneal fibrosis, an uncommon and ill-defined condition, has a variety of causes and presenting features. The fibrotic process often produces ureteral obstruction and compression of surrounding structures. Pain in the flank, lower abdomen or lumbosacral region is the most common presenting symptom. Certain drugs, neoplasms, retroperitoneal injury or infections may all initiate the fibrotic process. This article describes a case of retroperitoneal fibrosis in a 34-year-old man who had been receiving a beta-adrenergic blocking agent.

Adult↗
PubMedDate not supplied

Papillary carcinoma of the common bile duct. Diagnosis by bile drainage cytology.

A 54-year-old man with clinical and radiologic findings suggestive of pancreatic carcinoma had cytologic examination of bile drainage fluid specimens prepared by membrane filtration and cytocentrifugation. Examination showed clumps of malignant cells with features most consistent with a well-differentiated papillary neoplasm of bile duct origin, rather than a primary pancreatic carcinoma. Partial pancreatoduodenectomy with resection of the proximal common bile duct confirmed the presence of a small, well-differentiated but invasive papillary bile duct carcinoma. Pancreatic carcinoma and papillary carcinoma of the bile duct are anatomically and biologically different lesions that should be distinguished, when possible, by cytologic examination. In this case, surgical treatment was planned on the assumption that cytologic examination could distinguish a papillary carcinoma of the bile duct from the clinically suspected pancreatic adenocarcinoma.

Adenocarcinoma↗
PubMedDate not supplied

Intravenous immunoglobulin induced-nephropathy: a complication of IVIG therapy.

Since the early 1950s, intravenous immunoglobulin (IVIG) preparations are being used in the treatment of hematologic, neurologic, nephrologic, autoimmune, and immunodeficiency disorders. Infusion of IVIG preparations may cause osmotic-induced acute renal failure. Despite the fact that this entity has been reported previously, it is not a widely appreciated complication. A total of 22 reports involving 52 patients in whom renal failure occurred in association with IVIG infusion. The patients' ages ranged from 20 to 82 years. Thirty patients had preexisting renal insufficiency. Rise in serum creatinine was noted after 1-10 days of IVIG infusion and creatinine returned to baseline within 2-60 days of discontinuation. One developed end stage renal disease. There were four fatalities related to complications of renal failure. Histopathology of renal tissue showed osmotically induced tubular injury (5 patients), tubular vacuolization (2 patients), tubulointerstitial infiltrate (1 patient), and cryoglobulin deposits (1 patient). There appears to be no direct relationship between the development of acute renal failure and the type of IVIG. However, underlying renal insufficiency increases the risk of renal failure. In view of the increasing use of IVIG preparations in medicine, it is imperative that clinicians be aware of this unusual form renal injury.

Acute Kidney Injury↗