Biomedical subjects

B A Lwaleed

Publications and source records attributed to B A Lwaleed.

21 records · Page 2Linked to original sources

PubMed1999

Development and validation of an assay for urinary tissue factor activity.

BACKGROUND: Activation of blood coagulation is a common complication of cancer and inflammation in both humans and experimental animals. Increased production of tissue factor--the principal initiator of the coagulation process--by endothelial cells, monocytes, and macrophages has been implicated in these conditions. AIM: To investigate whether urinary tissue factor (uTF) might reflect the state of monocyte/macrophage activation and be a useful diagnostic test. METHODS: Urine was centrifuged at 51,000 g to sediment tissue factor containing membrane vesicles. The tissue factor was then solubilised in beta-octyl-glucopyranoside and assayed in a specific chromogenic assay adapted for use in microtitre plates. RESULTS: The assay proved to be sensitive, specific, and reproducible. The normal range of uTF was relatively narrow and unaffected by age, sex, or cigarette smoking. Levels were not significantly influenced by storage of urine samples before assay or by the presence of fresh blood in the urine sample. CONCLUSIONS: This method may have diagnostic application in the study of haemostatic activation in patients with cancer and other disease states.

Biomarkers, Tumor↗

PubMed1998

Effect of kidney function and disease status on urinary tissue factor measurements.

AIM: To investigate factors that influence urinary tissue factor (uTF) measurements: glomerular permeability and filtration, tubular function, haematuria, and urine bacterial growth. METHODS: uTF, protein creatinine index, glomerular filtration rate, retinol binding protein, N-acetyl-beta-D-glucosaminidase (NAG) and urinary haemoglobin (uHb) were measured in patients with hypertension, diabetes mellitus and nephrotic syndrome (n = 342), tubulo-interstitial disease (n = 50), and haematuria of uncertain cause (n = 50); measurements were also made in urine samples from healthy subjects for "simulated" haematuria (n = 6) and bacterial growth (n = 4) studies. RESULTS: There was a weak correlation of uTF with glomerular permeability and filtration (protein creatinine index and glomerular filtration rate) and with markers of tubular function (retinol binding protein and NAG). uTF concentrations were not affected by the presence of blood or bacteria in the urine sample. CONCLUSION: uTF concentrations are relatively stable. This is an important finding if the assay is to be used in clinical practice.

Acetylglucosaminidase↗

PubMed1997

Urinary tissue factor in glomerulonephritis: a potential marker of glomerular injury?

AIM: To investigate the significance of urinary tissue factor (uTF) concentrations in patients with glomerulonephritis. METHODS: Urine samples were collected from normal subjects (n = 57), patients with uncomplicated renal stones (n = 30), and patients with glomerulonephritis (n = 150). Samples were then centrifuged and the pellets solubilised in n-octyl-beta-glucopyranoside. uTF concentrations were determined using a one stage kinetic chromogenic assay. RESULTS: The uTF concentration was higher in patients with glomerulonephritis than in normal controls (p < 0.01) or in patients with renal stones (p < 0.05). uTF activity correlated with the protein creatinine index (PCI, r = 0.41, p < 0.001) and seven patients with glomerulonephritis and a PCI < or = 0.1 g/mmol had raised uTF. Glomerulonephritis patients were subdivided into two groups depending on the PCI: < 0.2 g/mmol creatinine (mild to moderate proteinuria, group I) and > or = 0.2 g/mmol creatinine (heavy proteinuria, group II). In group I, uTF concentrations were higher in patients with either immune complex (IC) glomerulonephritis (p < 0.01) or non-IC (p < 0.05) glomerulonephritis than in normal controls. In group II, the IC glomerulonephritis group had higher uTF concentrations than normal controls (p < 0.001) or patients with renal stones (p < 0.01); and non-IC glomerulonephritis patients had higher uTF than normal controls (p < 0.01). When the glomerulonephritis groups were divided into broad WHO subtypes, the significance level varied with the type of glomerulonephritis. CONCLUSIONS: uTF is increased in patients with glomerulonephritis, and its concentration may reflect the aetiopathogenesis of glomerulonephritis.

Biomarkers↗