Zeitschrift fur medizinische Laboratoriumsdiagnostik最新文献

The assay is based on the luminescent measurement of horseradish peroxidase. The IgG fraction of a cortisol antiserum is coated on suitable polystyrene tubes (in use for the measurement of luminescence). The enzyme activity of bound label was determined using a p-iodophenol enhanced chemiluminescent reaction. The assay was sensitive and precise for a wide cortisol concentration range and showed a good agreement with conventional ELISA-technique. There was no extraction necessary for cortisol from plasma. The diluted sample was heated to 60 degrees C or 8-aniline-1-naphthalene sulfonic acid was added in order to release cortisol from protein binding in plasma.

The determination of the LDL-receptor-activity with 125I-LDL according to Goldstein and Brown is regarded as reference method, because it permits the quantitative measuring of the partial receptor functions binding, internalization and degradation of LDL. The authors inform of their experiences with the assaying of the LDL-degradation in mononuclear blood cells (lymphocytes and monocytes). The most critical step of the method is the radioactive labelling of the LDL. The quality criteria of the labelling are discussed. The results of the receptor activity assays from patients with heterozygous familial hypercholesterolemia demonstrate that it is necessary to assay patients and normal persons for each 125I-LDL-lot and to calculate the data of the patients in relation to the normal persons because of the limited standardization of the method. In the clinical medicine, today the receptor assay is only indicated for the genetic counseling of patients which are suffering possibly from familial hypercholesterolemia.

The lipoprotein profile during an acute respiratory disease (ARD) was determined in 75 children from 8 Dresden day-nurseries. At time "O" when the children are free of any ARD the serum concentrations of TG, TC, LDLC and Apo B are high whereas those of HDLC, Apo AI and Apo AII are age-related. The acute stage of an ARD is characterized by high levels of TG, Apo B and Apo AII and an decrease in TC, LDLC, HDLC and Apo AI. After 4 weeks of reconvalescence some of these disturbances persist.

The effect of enkephalin derivates with different receptor subtype specificity and opioid antagonist naloxone on kallikrein-kinin system was studied in anaesthetized rats exposed to 30% hemorrhage. Hemorrhage by itself caused only a slight activation of KKS. Pretreatment with naloxone induced a significant activation of KKS, which was potentiated by subsequent hemorrhage.

In 30 patients suffered from acute myocardial infarction the serum levels of zinc, copper, cortisol, aldosterone, and triiodthyronine were determined. Zinc and triiodthyronine decrease, the other parameters increase. The serum levels of the tested parameters show a characteristic course within the first days after onset of myocardial infarction. There are significant differences between patients without complications and patients with complicated course inclusive of deaths. The differences exist already on the day of admission. Therefore we conclude zinc, copper, cortisol, and aldosterone levels as well as the course of T3 level are useful for prognosis of the clinical progress fo AMI. The tested parameters are helpful in differential diagnosis of chest pains caused by myocardial ischemia with or without myocardial infarction. The strong correlations between trace elements and hormones show new aspects due to the explanation of pathological alterations of serum levels in clinical medicine.

The concentration of neuraminic acid and proteins was determined in amniotic fluid of 207 pregnancies during the amniocentesis, performed in the 16.-21. week of gestation, 17 prematurities and 101 deliveries in time. The neuraminic acid/protein quotient increases significantly at term. Than, its reference range is 51.3-154.8 mumol/g (2.5-97.5 percentile). The neuraminic acid/protein quotient can be an useful prenatal indicator of the fetal maturity because of its high diagnostic specificity (97%) and sensitivity (88%).

Investigations of nitrogen and protein metabolism with the stable isotope 15N were carried out on 11 patients with atherosclerosis and 7 healthy control subjects. After oral application of 3 g 15NH4Cl (95 At% 15N) per 70 kg body weight the incorporation of the isotope 15N in plasma proteins and blood cells and the 15N elimination in urine were followed up. Retardations of 15N elimination, an accelerated incorporation of 15N in fibrin and a retarded 15N incorporation in platelet protein were observed in patients with atherosclerosis. The described method enables complex assertions about protein metabolism of the whole body and so represents a possibility to evaluate objectively the influence of an intervention on metabolism.

Administration of factor XIIf prepared from human plasma activated the kallikrein-kinin system in vivo. In rats there was a decrease in kallikreinogen as well as a short decrease of the mean arterial blood pressure. The results described are of importance for the research of pathogenesis of shock.

The effect of a new shock-protective agent LPH on parameters of the kallikrein-kinin-system was studied in a standardized endotoxin shock model. Activation of KKS in endotoxin shock was not significantly influenced by LPH. On the other hand, LPH by itself caused activation of KKS. Decrease of kininogen level by endotoxin, however, was prevented by the pretreatment with LPH.