Search PubMed⌕ Search

Biomedical subjects

T Koivula

Publications and source records attributed to T Koivula.

At least 73 records · Page 4Linked to original sources

Direct detection of Mycobacterium tuberculosis in sputum samples from Guinea Bissau by an rRNA target-amplified test system.

SETTING: There is a need for more sensitive and rapid methods for laboratory confirmation in the diagnosis of tuberculosis. OBJECTIVE: To investigate the applicability of a target rRNA amplified test system (AMTDT, Gen-Probe, CA) for rapid detection of Mycobacterium tuberculosis. DESIGN: The rRNA amplified test system was compared to standard methods for acid fast microscopy and mycobacterial culture for the demonstration of M. tuberculosis in sputum samples from 247 patients in Guinea Bissau with suspected tuberculosis. RESULTS: The highest incidence of positive samples was obtained with the AMTDT test. Out of 274 sputum samples 96 (35%) were positive by the AMTDT test, 82 (30%) were positive by culture and 38 (14%) by direct microscopy. Using culture as reference method the sensitivity of the test was 85% (after discrepancy analysis 87%), and the specificity was 86% (after discrepancy analysis 93%). CONCLUSION: The sensitivity and specificity of the AMTDT test used in this setting indicates that it may be a valuable complement for improving the laboratory diagnosis of tuberculosis.

Bacteriological Techniques↗

Mycobacterium avium complex sputum isolates from patients with respiratory symptoms in Guinea-Bissau.

In total, 814 patients with clinically suspected tuberculosis were examined at the Raoul Follerau Hospital in Bissau, Guinea-Bissau. Sputum samples were collected, and cultures were grown on Löwenstein-Jensen medium. Isolates were further characterized by standard biochemical methods and nucleic acid probes for Mycobacterium tuberculosis and Mycobacterium avium complex (MAC). Serum samples were collected and analyzed for antibodies against human immunodeficiency virus (HIV) types 1 and 2. Of 17 patients who had MAC organisms in sputum, 2 were HIV-2-positive and none was HIV-1-positive. Of the total 814 patients, 189 had culture-verified tuberculosis; 36 (19%) of them were HIV-2-positive. Thus, of 206 patients with sputum culture positive for M. tuberculosis or MAC, 17 (8%) had MAC organisms in sputum. MAC infection may be the cause of some treatment failures in areas where MAC pulmonary infection is common.

Adult↗

Apolipoprotein E polymorphism, serum lipids, myocardial infarction and severity of angiographically verified coronary artery disease in men and women.

In several populations, the apolipoprotein E (apo E) allele epsilon 4 is associated with high concentration of plasma total and low density lipoprotein (LDL)-cholesterol and coronary artery disease (CAD). We determined the apo E phenotypes of 309 patients with angiographically verified CAD and 38 patients without CAD by isoelectric focusing and Western blotting. In men with CAD, the plasma total and LDL-cholesterol increased according to apo E phenotype in the following order: E3/2 < E3/3 < E4/3 < E4/4 (P = 0.03 for total cholesterol, P = 0.007 for LDL-cholesterol). In women, there was a similar trend (P = 0.22 for total cholesterol, P = 0.15 for LDL-cholesterol). The relative frequency of men with three vessel CAD increased (P = 0.43) together with LDL-cholesterol levels (P = 0.05) according to apo E phenotype E3/2, E3/3, E4/3, E4/4. Total and LDL-cholesterol levels were higher in patients with three vessel CAD than in patients with less serious types of CAD (P = 0.02 for total cholesterol, P = 0.007 for LDL-cholesterol). The relative frequency of patients with myocardial infarction increased according to apo E phenotype (P = 0.51). Both in men and women, there were no differences between apo E phenotypes in age at occurrence of the first myocardial infarction. The apo E allele frequencies of patients with CAD vs. without CAD were 2.3% vs. 1.3% for epsilon 2, 79.0% vs. 76.3% for epsilon 3 and 18.7% vs. 22.4% for epsilon 4. There were no statistically significant differences in apo E allele or phenotype frequencies between patients with CAD and without CAD or between patients with CAD and the general Finnish population. Our results support previous studies in suggesting that the apo E allele epsilon 4 is a risk factor for atherosclerosis, which affects plasma total and LDL-cholesterol. In addition, our results suggest that the apo E allele determines the severity of CAD.

Age Distribution↗

Albumin excretion rate and its relation to kidney disease in non-insulin-dependent diabetes mellitus.

OBJECTIVE: To estimate the occurrence of increased albumin excretion rate (AER) and its significance as a marker of diabetic kidney disease in non-insulin-dependent diabetic subjects. DESIGN: Population-based, controlled cross-sectional study. SETTING: A primary health care centre in the city of Tampere, south-west Finland. SUBJECTS: Consecutive, recently diagnosed (n = 150) and long-term (n = 146) middle-aged non-insulin-dependent diabetic subjects. Matched non-diabetic control subjects (n = 150). MAIN OUTCOME MEASURES: Albumin excretion rate, fractional AER, microalbuminuria (AER 30-300 mg 24 h-1), clinical nephropathy (AER exceeding 300 mg 24 h-1) and kidney biopsy in diabetic subjects with an AER exceeding 100 mg 24 h-1. RESULTS: Mean (+/- standard deviation [SD]) 24-h AER was increased in recently diagnosed diabetic subjects, 54 (111) mg, and long-term diabetic subjects, 134 (479) mg, compared to non-diabetic control subjects, 16 (19) mg. The fractional AER was 7.5 (18.3) x 10(-6) in recent diabetic subjects, 53.1 (306.9) x 10(-6) in long-term diabetic subjects and 2.8 (3.7) x 10(-6) in non-diabetic control subjects. Microalbuminuria was found in 8% of non-diabetic subjects, in 29% of recent and in 27% of long-term diabetic subjects. The prevalence of clinical nephropathy was 7% in long-term and 4% in recent diabetic subjects, whilst no non-diabetic subject had nephropathy. In 12 of 16 eligible kidney biopsies, diabetic glomerulosclerosis was found, in four subjects the finding was normal. CONCLUSIONS: The AER is clearly increased in recent non-insulin-dependent diabetic subjects and further increased in diabetic subjects with a mean disease duration of 10 years. An increased AER in non-insulin-dependent diabetic subjects suggests diabetic kidney disease.

Adult↗

Possibilities for quality assurance of reference intervals.

Most clinical laboratories participate in surveys of external quality assurance (EQA). The results are not, however, very commonly or effectively applied to controlling the accuracy, i.e., differences in the analytical level. Therefore, it is important that each laboratory has its own, valid reference values. Nevertheless, many laboratories do not follow the internationally accepted recommendations for determining reference intervals or use reference values from other laboratories or from literature. Techniques of the external quality assurance can be extended to the checking of the validity of reference limits.

Humans↗

Estimation of reference change limits using patient data.

Two approaches for deriving reference change limits from patient data are described. In the direct method, hospital database information is used for the selection of appropriate reference groups. If database information is not sufficient or reliable enough, but still most of the source data can be considered as health-related, an indirect method can be applied in the calculation of rough estimates for reference change limits. A computer program developed by us, GraphROC for Windows, includes both methods for the estimation of change limits from patient data. Time between specimen collections should be included as one classifying factor in the selection of source data. When only one previous result is available for comparison, change limits based on the reference sample group form the only available guide for clinical interpretation. However, when several previous results are available and the within-subject variances for the considered analyte are known to be heterogeneous between individuals, the clinical interpretation should rather be based on application of time series analysis.

Data Interpretation, Statistical↗

Reliability and adequacy of discharge diagnosis databases in the production of reference values.

Discharge diagnoses provide a possibility to select patients individually and then to establish reference values for both "pathological" and control groups. Currently, the available diagnostic information is still at its infancy and should be carefully evaluated before the reference values based on those groups are utilized. It is anticipated that electronic storage of diagnostic and therapeutic information will be applied more commonly in the future as the development of computers makes it easier. The advanced utilization of laboratory data challenges physicians both in the clinical and laboratory side to participate in this development in order to make the information systems serve their actual needs more closely.

Clinical Laboratory Information Systems↗

Blood tests for detection of alcoholic cause of acute pancreatitis.

We investigated the ability of various blood markers to detect an alcoholic cause of acute pancreatitis. Serum carbohydrate-deficient transferrin (CDT) was significantly correlated with reported 2 month and 7 day ethanol consumptions and was significantly higher in 42 patients with alcoholic acute pancreatitis and in 24 patients with possibly alcoholic acute pancreatitis than in 20 patients with non-alcoholic disease. At a cutoff over 17 U/L, the specificity of CDT was 100% and the sensitivity was 75% to detect an alcoholic cause of acute pancreatitis. The lipase/amylase ratio index, erythrocyte mean corpuscular volume, and gamma glutamyl transferase could not distinguish alcoholic from non-alcoholic acute pancreatitis.

Acute Disease↗

Postprandial plasma lipoprotein changes in relation to apolipoprotein E phenotypes and low density lipoprotein size in men with and without coronary artery disease.

Postprandial lipoprotein metabolism may play a role in the etiology of premature coronary artery disease (CAD). To determine whether apolipoprotein E (apo E) polymorphism and the size of low density lipoprotein (LDL) influence postprandial lipemia we studied 39 healthy men and 35 men with CAD. Venous blood samples were obtained before an oral fat load and 3, 5 and 7 h thereafter. Total cholesterol and high density lipoprotein (HDL) cholesterol concentrations did not change in either group during the fat load, but triglycerides increased more markedly in CAD patients compared with controls independently of apo E phenotypes. There was a positive correlation between the size of LDL and the concentration of HDL cholesterol (r = 0.541, P < 0.001); conversely, an inverse correlation was observed between LDL size and the level of fasting triglycerides (r = -0.582; P < 0.001). The patients with CAD had significantly smaller LDL particles (25.89 +/- 0.56 nm) than in controls (26.21 +/- 0.63 nm) (P < 0.05). The increase in triglyceride levels during the fat load was highest in CAD patients with a small size of LDL particles (< 25.5 nm) and lowest in controls with large LDL (> 25.5 nm). Our results suggest that the magnitude of the triglyceride response is a better indicator of CAD risk than the fasting triglyceride concentration. The best model in our logistic regression analysis selected as significant risk factors the change of triglyceride concentration from the baseline at 5 h after a fat meal and HDL cholesterol. This model classified 83% of the subjects correctly.

Adult↗

Overexpression of p53 and long-term survival in colon carcinoma.

Survival analysis of 144 histologically confirmed cases of colon carcinoma diagnosed in a 12 year period (1971-82) at the Tampere University Hospital was performed to test the hypothesis that p53 overexpression is associated with a poor clinical outcome. Immunohistochemical staining of paraffin-embedded sections using a polyclonal antibody CM-1 against p53 protein was performed to identify aberrant expression of the p53 tumour-suppressor gene. Sixty-nine per cent of the tumours (100/144) showed overexpression of the p53 protein. The prevalence of p53 overexpression was independent of age and sex of the patient and subsite of the tumour, but was slightly, although not statistically significantly, higher in advanced than in localised tumours. Overexpression was associated with a higher S-phase fraction. Some indication of a larger proportion of aneuploid tumours among those with overexpression was also observed, although this finding did not reach statistical significance. Significantly reduced patient survival for tumours with p53 overexpression was found. Patients with p53-overexpressing tumours had a corrected 5 year survival rate of 37% compared with 58% among patients whose tumours had normal expression of p53. The corresponding 10 year rates were 34% and 54%. In the multivariate analysis using a Cox model, the survival difference was independent of age and sex of the patient, as well as of subsite and stage of the tumour. Furthermore, the effect of p53 overexpression remained after controlling for flow cytometric parameters in an analysis of a subset of tumours. Thus, p53 overexpression appears to be a useful prognostic indicator in colon carcinoma.

Adolescent↗

Carbohydrate-deficient transferrin as an alcohol marker among female heavy drinkers: a population-based study.

Carbohydrate-deficient transferrin (CDT) has previously been reported to be an excellent marker of male alcoholics. Less is known of its efficiency among women and especially of early-phase alcohol abuse in nonselected populations. The present population-based study examined the diagnostic value of CDT among consecutive women, including 13 teetotallers, 135 social drinkers (mean alcohol consumption 45 +/- 34 g/week), and 57 nonalcoholic heavy drinkers (197 +/- 97 g/week). Sixty-two women with a well-documented history of chronic alcoholism (942 +/- 191 g/week) were also studied, as well as 36 pregnant women used as a reference group. Two weeks of abstinence among 11 alcoholics was followed. The CDT (containing part of isotransferrin with pI = 5.7, 5.8, and 5.9) was separated by anion exchange chromatography and assayed by radioimmunoassay. In the whole material, CDT correlated significantly with alcohol consumption (r = 0.43, p < 0.001) but not with conventional markers (gamma-glutamyltransferase, AST, ALT, and mean corpuscular volume). The CDT values of alcoholics (34 +/- 20 units/liter) were significantly (p < 0.001) higher than those of teetotallers (19 +/- 6 units/liter), social drinkers (20 +/- 6 units/liter), or pregnant women (16 +/- 3 units/liter). Heavy drinkers also had higher values (25 +/- 13 units/liter), but the difference did not reach statistic significance. The specificity of CDT was on the level of conventional markers when the cut-off value was increased from 26 to 29 units/liter. At a specificity of 95%, CDT found 19% of the heavy drinkers and 52% of the alcoholics; the best traditional marker, AST, with a specificity of 97%, found 7% and 56%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Acute pancreatic injury in asymptomatic individuals after heavy drinking over the long-term.

Recently, high-dose short-term alcohol exposure has been observed not to induce acute pancreatic damage, as evaluated by serum pancreatic enzyme activities. In this study the effect of high-dose, long-term alcohol exposure on the pancreas was investigated in 32 consecutive alcoholics admitted to a unit to treat the problems of withdrawal after a long period of heavy drinking. None of the alcoholics complained of abdominal symptoms. The signs of clinical acute pancreatitis (pain, increased serum C-reactive protein concentration or blood white cell count) were not observed in any of the alcoholics. A significant increase in serum total amylase, pancreatic isoamylase and lipase activities developed by the second day after termination of alcohol intake. These enzyme activities remained significantly increased for one week after cessation of drinking. Seven alcoholics had signs of chronic pancreatitis at ultrasonography (pancreatic calcification, pseudocyst). These results suggest that heavy alcohol intake over the long term may frequently induce subclinical pancreatic injury.

Acute Disease↗

Reference intervals developed from data for hospitalized patients: computerized method based on combination of laboratory and diagnostic data.

We utilized the databases of a hospital information system to select for determination of reference values various individual hospitalized patients on the basis of their diagnoses at discharge. The nonparametric 2.5-97.5% "health-related" reference intervals were calculated for hemoglobin concentration, mean corpuscular volume (MCV), and erythrocyte count for both sexes. After excluding patients with diseases possibly affecting erythrocyte variables, we obtained a final group of 1786 women and 1450 men, ages 20-65 years, who were studied in age groups of 20-30, 30-45, 45-55, and 55-65 years. The upper reference limits of the MCV results obtained from hospitalized patients were higher than those produced conventionally from healthy individuals, as would be intuitively suggested by clinical experience. This method, based on selection by diagnosis, could be applicable to various analytes measured in hospital laboratories, provided sufficient data are available as databases.

Adult↗

Amount of alcohol is an important determinant of the severity of acute alcoholic pancreatitis.

BACKGROUND: Does the amount of recently consumed alcohol correlate with the severity of acute alcoholic pancreatitis? METHODS: One hundred one consecutive episodes of acute pancreatitis (AP) were prospectively studied. Seventy-three were alcoholic AP episodes; 40 patients had their first alcoholic AP episode. A standard personal interview was used to determine the alcohol consumption during 2 months and during 1 week before AP. The severity of AP was evaluated according to the Ranson criteria, the serum C-reactive protein (CRP) concentration measured 24 to 48 hours after admission, the length of the hospital stay, the development of complications, and the mortality rate. RESULTS: In the 40 patients having their first alcoholic AP episode, the reported 2-month alcohol consumption correlated significantly with the number of positive Ranson criteria (correlation coefficient r = 0.44, p < 0.01), serum CRP concentration (r = 0.51, p < 0.001), and the length of the hospital stay (r = 0.45, p < 0.01). Complications occurred in eight of 14 patients with 2-month alcohol consumption of more than 5000 gm as compared with one of 14 patients with consumption of less than 2000 gm (p < 0.05). In the same 40 patients the 1-week alcohol consumption correlated with the number of positive Ranson criteria (r = 0.40, p < 0.05) and serum CRP concentration (r = 0.37, p < 0.05). Of the 12 patients who had consumed more than 1000 gm alcohol during the last week before admission, two died and complications developed in six (50%), as compared with none (p < 0.05) and six (21%), respectively, of those who had consumed less than 1000 gm. No significant correlations were observed between the reported alcohol consumption and any of the severity parameters in the 33 patients with recurrent episodes of alcoholic AP. CONCLUSIONS: The amount of alcohol consumed may be an important determinant of the severity of the first alcoholic AP episode but not of recurrent alcoholic AP.

Acute Disease↗

Semi-automatic method for determination of different isoforms of carbohydrate-deficient transferrin.

Carbohydrate deficient transferrin (CDT) has been reported to be one of the best biochemical markers of alcohol abuse. However, a need still exists for a simple and practical method for widespread laboratory use. A semi-automatic (SA) isoelectric focusing (IEF) assay for CDT (SA-IEF-CDT) by a Phast System is introduced here. Different isoforms of transferrin were separated by IEF on polyacrylamide gels (pI 4.0-6.5) and located by immunofixation with an anti-transferrin serum. The precipitation bands were stained with Coomassie Brilliant Blue and quantitated densitometrically. The present method gave a picture of the relative amounts of 10 different transferrin isoforms. The percentage of CDT with pI > or = 5.7 (representing di-, mono- and asialotransferrin) was calculated. For comparisons transferrin bands with pI > or = 5.6 (tri-, di-, mono-, and asialotransferrin), pI > or = 5.8 (mono- and asialotransferrin) and pI > or = 5.9 (asialotransferrin) as well as GGT, ASAT and ALAT were calculated. The method showed good linearity and it identified different isoforms in concentrations of < 10 mg/l of transferrin. The correlation of the present method with a commercially available method employing anion exchange followed by double antibody RIA (AE-RIA-CDT) was good (n = 38, r = 0.924). In 19/20 (95%) of healthy controls, the CDT value was below 4.4% (mean + 2 S.D.) of total transferrin, while higher values were observed in all 20 (100%) alcoholics. In conclusion, the developed semi-automatic method is a practical and reliable alternative for determination of different transferrin isoforms.

Adult↗

DNA ploidy, cell proliferation and steroid hormone receptors in endometrial hyperplasia and early adenocarcinoma.

We determined DNA content, S-phase fraction, and estrogen (ER) und progesterone receptor (PR) levels in 36 stage I endometrial adenocarcinomas and in 22 hyperplastic lesions to obtain information on the genesis and progression of endometrial malignancy. DNA aneuploidy was detected in 12/36 (33%) carcinomas and in none of the hyperplastic lesions. DNA aneuploidy was significantly more common in poorly and moderately differentiated carcinomas than in the well-differentiated ones. Similarly, the highest number of cells in S-phase were found in poorly and moderately differentiated carcinomas, whereas well-differentiated carcinomas and all hyperplasias had an equally small S-phase fraction. Mean ER and PR levels were highest in hyperplastic lesions, especially those with atypical features, whereas carcinomas of all grades had significantly lower values. Thus, it is likely that the loss or decreased expression of steroid receptors is an early event during carcinogenesis in human endometrium, whereas an increase in the cell proliferation rate and the formation of DNA aneuploidy occur later during tumor progression.

Adenocarcinoma↗

Relationship of alcohol consumption to changes in HDL-subfractions.

Epidemiological studies have consistently shown an apparent protective effect of moderate alcohol consumption on coronary artery disease (CAD). This has been considered to be due to the rise in the high-density cholesterol lipoprotein (HDL-cholesterol). Since the response of the HDL-subfractions to moderate or heavy dose of alcohol is less clear, we now compared the high-density lipoprotein cholesterol status between groups consuming different amounts of alcohol. In this population-based survey serum total high-density lipoprotein cholesterol and its HDL2 and HDL3 subfractions were blindly compared between 264 consecutive middle-aged men (37 teetotallers, 137 moderate drinkers, 90 heavy drinkers) participating in a voluntary health screening and 104 male alcoholics. Alcohol consumption correlated significantly (P < 0.001) with total HDL-cholesterol, HDL2, HDL3 when all subjects (n = 368) were included but the correlation disappeared when alcoholics were excluded (n = 264). In comparison with teetotallers, alcoholics had significantly higher total HDL-cholesterol, HDL2 and HDL3 values (P < 0.001). Moderate or heavy intake of alcohol had no effect on HDL2 but increased the HDL3-fraction. If the protective effect of moderate alcohol consumption is mediated by high-density lipoprotein, it may not be accounted for by changes in the HDL2-fraction. The observed increases in the concentration of the HDL3-fraction, however, suggest that this subfraction may not be inert with respect to coronary disease and could possibly have a role in the protective effect.

Adult↗