Biomedical subjects

Petter Urdal

Publications and source records attributed to Petter Urdal.

5 recordsLinked to original sources

PubMed2005

Early detection of breast cancer based on gene-expression patterns in peripheral blood cells.

INTRODUCTION: Existing methods to detect breast cancer in asymptomatic patients have limitations, and there is a need to develop more accurate and convenient methods. In this study, we investigated whether early detection of breast cancer is possible by analyzing gene-expression patterns in peripheral blood cells. METHODS: Using macroarrays and nearest-shrunken-centroid method, we analyzed the expression pattern of 1,368 genes in peripheral blood cells of 24 women with breast cancer and 32 women with no signs of this disease. The results were validated using a standard leave-one-out cross-validation approach. RESULTS: We identified a set of 37 genes that correctly predicted the diagnostic class in at least 82% of the samples. The majority of these genes had a decreased expression in samples from breast cancer patients, and predominantly encoded proteins implicated in ribosome production and translation control. In contrast, the expression of some defense-related genes was increased in samples from breast cancer patients. CONCLUSION: The results show that a blood-based gene-expression test can be developed to detect breast cancer early in asymptomatic patients. Additional studies with a large sample size, from women both with and without the disease, are warranted to confirm or refute this finding.

Analysis of Variance↗

PubMed2005

Increased serum formate in the diagnosis of methanol poisoning.

Early diagnosis is essential for successful treatment in methanol poisoning. Methanol detection by gas chromatography is not available in most hospitals. Methanol increases the osmolal gap in serum and its metabolite formate increases the anion gap. The sensitivity of these indirect diagnostic methods is not good at low concentrations of methanol or formate. We therefore studied the usefulness of formate measurement in diagnosing methanol poisoning. In 15 patients poisoned with methanol, serum formate was measured enzymatically on a Cobas Mira analyzer using formate dehydrogenase and nicotinamid adenine dinucleotid. Day-to-day coefficient of variation was 5%, and the upper reference limit was 2 mg/dL (0.4 mmol/L). Methanol was detected in all 15 patients of whom 14 had elevated serum formate concentrations. Anion gap was increased in 11 of 11, and osmolal gap in 11 patients of 15 examined. Metabolic acidosis was present in 12 of 15 patients, but pH was below 7.30 in only 9 of them. Four patients with no symptoms had formate concentrations in the range 2-38 mg/dL (0.5-8.3 mmol/L), indicating that increased serum formate was a sensitive indicator of methanol poisoning. Our results proved formate analyzes to be a simple, sensitive, and specific way of diagnosing methanol poisoning. Confounders are patients admitted early, or concomitant ethanol ingestion, and therefore no acidosis. This problem may, however, be omitted by repeated formate analysis in patients developing metabolic acidosis.

Adult↗

PubMed2005

Prevalence of cardiovascular diseases and associated risk factors in a rural black population of South Africa.

BACKGROUND: To determine the prevalence and associated risk factors of cardiovascular diseases in a rural adult black population from Limpopo Province in South Africa. DESIGN: A cross-sectional study. METHODS: A sample of 1608 women and 498 men aged 30 years and above participated in the study. Sociodemographic data, anthropometric measures (body mass index, waist/hip ratio), blood pressure and biochemical risk factors were measured. A global cardiovascular disease (CVD) risk profile was developed. RESULTS: There was a high prevalence of tobacco use for men (57%) and women (35.4%), with women (28.1%) predominantly using smokeless tobacco. Alcohol use was very common in men (57.2%). Women weighed a great deal more than men, and 51.7% were either overweight or obese. Diabetes was diagnosed in 8.8 and 8.5% of women and men, respectively. High-density lipoprotein-cholesterol was relatively high, whereas 42.3% of women and 28.5% of men had low-density lipoprotein-cholesterol levels of 3 mmol/l or more. Hypertension (blood pressure > or =140/90 mmHg) was found in 25.5% of women and 21.6% of men. According to the Framingham formulae, 18.9% of women and 32.1% of men had a 20% or higher chance of having a CVD event in the next 10 years. CONCLUSIONS: There was a high prevalence of chronic disease risk factors in the rural, poor black community in Limpopo, South Africa. Consequently, the population had a higher than expected risk of developing a CVD event in the following 10 years when compared with similar studies in black Africans.

Adult↗

PubMed2005

Methanol and formate kinetics during treatment with fomepizole.

OBJECTIVE: Methanol is metabolized by alcohol dehydrogenase to formaldehyde, and further to formic acid, which is responsible for the toxicity in methanol poisoning. Fomepizole (4-methylpyrazole) is a potent competitive inhibitor of alcohol dehydrogenase and is used as an antidote to treat methanol poisonings. We report serum methanol kinetics in eight patients treated with bicarbonate and fomepizole only. METHODS: Prospective case series study of eight patients with methanol poisoning, who were selected to fomepizole and bicarbonate treatment only, because of moderate metabolic acidosis. Three of the patients were later dialyzed, because of high serum methanol concentrations and very slow methanol elimination. RESULTS: Upon admission the median pH was 7.27 (range 7.12-7.50), median base deficit was 15 mmol/L (5-22 mmol/L) and median serum methanol was 20.4 mmol/L (65 mg/dL) (range 8.4-140.6 mmol/L). The kinetics of methanol during fomepizole treatment in six patients was best described by a first-order elimination one-compartment model. The mean correlation coefficient (R2) describing the first-order elimination model in all eight patients was 0.95 (range 0.90-0.99). The mean plasma half-life (t(1/2)) of methanol during fomepizole treatment was 52 h (range 22-87); the higher the serum methanol, the longer the T(1/2). Mean half-life of serum formate was 2.6 h, when methanol metabolism was assumed blocked by fomepizole and no folinic acid was given. This rapid formate elimination in nonacidotic patients may be explained by high renal excretion of formate. CONCLUSION: Based on our data, methanol-poisoned patients with moderate metabolic acidosis and methanol levels up to 19 mmol/L (60 mg/L) may safely be treated with bicarbonate and fomepizole only, without dialysis.

Acidosis↗

PubMed2004

[Updated reference intervals for clinical chemical components].

BACKGROUND: More or less outdated reference intervals are still in common use with many clinical biochemical components. In order to update them, a Nordic cooperative project (the Nordic reference interval project, NORIP) was organised. MATERIAL AND METHODS: 102 Nordic laboratories participated; 3036 persons aged 18 years or above were included. 25 components were measured in serum and/or plasma. RESULTS: Common reference intervals for all Nordic countries were calculated for each of the 25 components, with age and sex-specific intervals when statistical criteria suggested this to be appropriate. INTERPRETATION: The national clinical biochemical societies of Norway, Sweden, Finland and Denmark have all recommended that the suggested reference intervals should be brought into common use. In Norway, new reference intervals for seven enzymes were implemented in May 2003, the remaining are recommended implemented in spring 2004. Except for four of the enzymes, there will be no simultaneous change in the measuring methods used, hence medical decision limits are essentially not affected.

Adolescent↗