European journal of clinical chemistry and clinical biochemistry : journal of the Forum of European Clinical Chemistry Societies最新文献

The polymerase chain reaction (PCR) has been successfully employed for the laboratory analyses of genetic and infectious disorders using DNA extracted from paraffin-embedded tissues. However, fixative type and fixation time influenced PCR reactions and in some circumstances amplification fragments could not be efficiently generated. In this study, we determined the effects of three commonly used fixatives including ethanol, formalin and Histochoice, on the PCR amplification of DNA from paraffin-embedded breast cancer tissue. The effect of fixatives and fixation times was measured by the ability of the extracted DNA to serve as a template for the amplification of 280 and 530 base pair DNA fragments. On amplifying DNA, positive reactions were uniformly seen in the ethanol specimens. The next best fixative was Histochoice with positive results almost constantly observed in the PCR reactions performed. Formalin fixation sometimes compromised DNA amplification. Our results are consistent with previous reports investigating the effect of ethanol and formalin fixation on DNA amplification by PCR. Moreover, this is the first study showing that paraffin-embedded tissues fixed with Histochoice can be efficiently used for PCR gene amplification.

Matrix effects hinder the transferability of accuracy for cholesterol. A general assumption is that pooled and individual samples yield similar results. We tested the hypothesis that serum-pooling affects the recovery for cholesterol. We pooled 100 serum samples, determining cholesterol of pool and of the individual samples with Hitachi 717 and 914. Over twenty days, we daily determined cholesterol of individual and pooled samples, using a Hitachi 736 and 747 analyzers. For the hundred-sample pool, the pool was 1.1 to 1.5% lower than the individual samples. With the daily pool study, the ratio of 747 to 736 was 1.7% lower for the pooled compared with the individual samples. Therefore, pooling of serum samples causes a decreased recovery, averaging from 1.1-1.7%, and representing 37-57% of the allowable bias for cholesterol (< 3%), and it is thereby significant.

Values for red blood cell distribution width yield information concerning size heterogeneity of red blood cell populations. Comparative studies between various haematology analysers are obligatory to quantify apparatus-dependent deviations with respect to accuracy and subsequent consequences with respect to clinical interpretation of results. In this study a comparative assessment is performed between a Sysmex SF-3000 and NE-8000 Haematology Analyser. Fifty-four specimens with abnormal red blood cell volumes and a hundred specimens from apparently healthy subjects were assayed. Systematic deviations in values concerning red blood cell distribution width are demonstrated to show a tendency to decrease towards higher mean corpuscular volume values.

Lactate dehydrogenase isoenzymes have been used to classify the nature of pleural effusion. Nevertheless, studies have reported conflicting results. The objective of this study was to evaluate the diagnostic value of lactate dehydrogenase isoenzymes in the analysis of pleural effusions. Pleural fluid samples obtained from three respective diagnostic groups: group I transudate (n = 23), group II parapneumonic effusion (n = 29) and group III malignant effusion or pleuritis carcinomatosa (n = 41) were evaluated. Total lactate dehydrogenase activity and lactate dehydrogenase (LDH) isoenzyme pattern were significantly different between transudative (group I) and exudative (group II and III) effusions. Group II and III showed a low percentage of LDH1 (p < 0.001), whereas the percentages of LDH4 (p < 0.001) and LDH5 (p < 0.001) were higher compared to group I. Moreover, in exudative effusions the percentage of LDH1 (p < 0.005), LDH4 (p < 0.005), as well as LDH5 (p < 0.005) were significantly different between parapneumonic and malignant effusions. In contrast to relative lactate dehydrogenase isoenzyme values, the absolute values of lactate dehydrogenase isoenzymes did not differ between group II and group III. Logistic regression analysis yielded a strong discrimination between group I and II+III, simultaneously using lactate dehydrogenase, glucose and protein as explanatory variables. Logistic regression analysis yielded only a weak discrimination between group II and III, simultaneously using lactate dehydrogenase, glucose and the absolute values of LDH2 and LDH4 as explanatory variables. In conclusion, the lactate dehydrogenase isoenzyme pattern differed between pleural effusions of transudative and exudative origin. However, including lactate dehydrogenase isoenzyme activities in the biochemical work-up of pleural effusions did not reveal an additional discriminatory value in the assessment of the classification of these effusions.

The present multicentre clinical study was conducted to assess the clinical utility of a new diagnostic method for deep mycosis in which (1-->3)-beta-D-glucan, a fungal cell wall component existing in plasma, was quantitatively measured by the kinetic turbidimetric Limulus test (WB003). Plasma (1-->3)-beta-D-glucan concentrations were 0.57 +/- 0.10 microgram/l in 92 healthy subjects and 0.62 +/- 0.32 microgram/l in 26 patients with non-mycotic diseases (disease control group). In comparison with these healthy subjects and patients with non-mycotic diseases, patients with mycosis had significantly higher plasma (1-->3)-beta-D-glucan concentrations: 19.63 +/- 73.28 micrograms/l in 12 patients with candidaemia, 11.28 +/- 21.42 micrograms/l in 7 patients with urinary Candida infection, 4.84 +/- 12.71 micrograms/l in 5 patients with pulmonary candidiasis, and 12.21 +/- 31.31 micrograms/l in 4 patients with invasive pulmonary aspergillosis. On the statistical analysis of these data, a cut-off value was set at 1.0 microgram/l. Using this cut-off value, 3 patients with pulmonary cryptococcosis and 4 patients (4/6) with pulmonary aspergilloma were all negative with low plasma (1-->3-beta-D-glucan levels. The test WB003 provided equivalent or higher efficiency of diagnosis of candidiasis and aspergillosis, in comparison with commercially available antigen detection kits, demonstrating its utility as a diagnostic reagent. It may also be useful in assessing therapeutic effectiveness when used periodically after treatment.

We report a method for the determination of 18 beta-glycyrrhetinic acid (glycyrrhetinic acid) in human serum using the ALCA-system. The technology of the ALCA-system is based on the principles of adsorptive and desorptive processes between liquid and solid phases. The assay is run fully automated and selective. Procedural losses throughout the analysis are negligible, thereby allowing for external calibration. The calibration curve is linear up to 10 mg/l and concentrations as low as 10 micrograms/l are detectable. CV is 2.5% for within- and 7.5% for between-assay precision at a level of 50 micrograms/l and 1.2% for within- and 8.5% for between-assay precision at a level of 500 micrograms/l. Specific and expensive reagents are not necessary and time-consuming manual operations are not involved. This assay can be selected from a wide spectrum of methods at any time. Thus, the present method is well-suited for drug monitoring purposes in the routine laboratory. In a pharmacokinetic study we measured serum levels of glycyrrhetinic acid in ten healthy young volunteers after ingestion of 500 mg glycyrrhetinic acid. Maximum levels of glycyrrhetinic acid were 6.3 mg/l 2 to 4 hours after ingestion. Twenty-four (24) hours after ingestion seven probands still had glycyrrhetinic acid levels above the detection limit with a mean level of 0.33 mg/l.

Between 1954 and 1996 a total of 16 International Congresses of Clinical Chemistry were held. Their main features are reviewed: their size and location; organisation and costs; the awards made to eminent clinical chemists; the publication of congress proceedings; the scientific content of congresses; and the role of industry. These have all changed over this period in a way which reflects the development of clinical chemistry. Although these congresses are becoming increasingly expensive, and cannot satisfy the needs of everyone, they are unique in providing a comprehensive and up-to-date overview of the subject and enabling clinical chemists from different countries to meet and exchange ideas and experiences.

Copper-zinc superoxide dismutase (Cu,Zn-superoxide dismutase) activity was evaluated in lymphocytes and polymorphonuclear cells of insulin-dependent (n = 33) and non-insulin-dependent (n = 34) diabetic patients. A commercial method for the measurement of superoxide dismutase activity was adapted for use on a discrete analyser and evaluated for interference by other antioxidants with superoxide anion-scavenging properties. In comparison to healthy control subjects (n = 32), a significantly lower Cu,Zn-superoxide dismutase activity was found in both lymphocytes and polymorphonuclear cells of insulin-dependent (2.08 +/- 0.58 vs. 1.70 +/- 0.46 U/mg protein, p < 0.05, and 1.06 +/- 0.46 vs. 0.64 +/- 0.40 U/mg protein, p < 0.001, respectively) and non-insulin-dependent diabetic patients (2.08 +/- 0.58 vs. 1.61 +/- 0.48 U/mg protein, p < 0.01, and 1.06 +/- 0.46 vs. 0.53 +/- 0.24 U/mg protein, p < 0.001, respectively). There was a week, but significant negative correlation between age and Cu,Zn-superoxide dismutase activity in lymphocytes and polymorphonuclear cells (r = -0.22 and r = -0.28, p < 0.05, respectively), whereas no influence of gender, diabetes duration and glycaemic control was observed. The results indicate that diabetes mellitus could elicit a significant disturbance in superoxide anion-scavenging potential of lymphocytes and polymorphonuclear cells.

An appropriate term is sought for the concept embracing the different types of clinical laboratory work. The defining characteristics of the concept are therefore described, i.e. site, goal, objectives, activity, field, and participating professionals. It is proposed that the superordinate concept should be "medicine" while the subordinate concept under discussion is defined on the basis of the characteristics, thereby distinguishing it from coordinate concepts, i.e. from other branches of medicine. The principles used for establishing existing terms in other branches of medicine are presented, together with a discussion of existing terms in the clinical laboratory field. It is suggested that the current term 'laboratory medicine' has several advantages. The workplace may be called a 'department of laboratory medicine' or 'clinical (or medical) laboratory'. It is further suggested that the term 'clinical chemistry' should not generally be replaced by 'clinical biochemistry'.