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Brick stones collected from different production facilities were studied for their elemental compositions under forensic aspects using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF). The aim of these examinations was to assess the potential of these methods in forensic comparison analyses of brick stones. The accuracy of the analysis methods was evaluated using NIST standard reference materials (679, 98b and 97b). In order to compare the stones to each other, multivariate data analysis was used. The evaluation of the INAA results (based on the concentrations of V, Na, K, Sm, U, Sc, Fe, Co, Rb and Cs) using principal component analysis (PCA) and cluster analysis is presented as an example. The results derived from the different analytical methods are consistent. It was shown that elemental analysis using the described methods is a valuable tool for forensic examinations of brick stones.

Samples from 20 reverse paintings on glass from different regions have been analyzed by NAA with the aim to deduce the place and date of their origin. A separation of earlier and later paintings was due to different concentrations of K and Na, because a sodium-containing flux came into use after 1870. Since in southern Germany quartz sand, and in the eastern area quartz rock had been used for glass manufacture, specific impurities could be used to distinguish southern from eastern glasses.

For the application of the BNCT for the excorporal treatment of organs at the TRIGA Mainz, the basic characteristics of the radiation field in the thermal column as beam geometry, neutron and gamma ray energies, angular distributions, neutron flux, as well as absorbed gamma and neutron doses must be determined in a reproducible way. To determine the mixed irradiation field thermoluminescence detectors (TLD) made of CaF(2):Tm with a newly developed energy-compensation filter system and LiF:Mg,Ti materials with different (6)Li concentrations and different thicknesses as well as thin gold foils were used.

Background: The classic methods for surveilling the efficacy of radiotherapy in prostate cancer are not accurate enough. The objective of this analysis was to determine whether prostate-specific antigen could perform this task., Materials and Methods: From 1/95 to 10/95, 16 patients were treated at our clinic. 7 of these underwent primary irradiation, 4 treatment for local recurrence, and 5 had adjuvant radiotherapy. Radiotherapy was carried out with a total dose of 60 Gy in 30 fractions, 10 fractions per week, to the prostate bed plus 2 cm safety margin., Results: PSA levels usually start to decline between the 3rd and the 4th week of radiotherapy with a half-life of 2.5 months. Five patients had equal or rising PSA levels, including all three patients with recurrent tumor., Discussion: In most cases, PSA declined continuously from the 3rd week of therapy. Our median half-life was similar to other reported results. Persisting or rising PSA levels are an indicator for local or distant recurrence; all our patients who developed a recurrence showed a corresponding PSA increase.

Background: Keratoacanthoma is a fairly common, benign, usually self-resolving skin lesion that arises from the hair follicle. This nodular lesion shows a predilection for areas exposed to light, mainly for the face. We report on the intensive radiation therapy of 2 cases of a rare subset of keratoacanthoma which showed a locally aggressive, seriously destructive growth., Patients and Methods: Two female patients with previously treated, confluent-destructive growing keratoacanthoma were treated by multimodal, high-dose radiotherapy. Patient 1 showed a rapid progress of midfacial tumor with destructive infiltration of the left cheek, nasal cartilage, the cribriform plate of ethmoid and congestion of the conjunctiva close to the lacrimal caruncle. This could be shown in clinical and histopathological investigations and CT-scans. The coexistence of cutaneous and conjunctival lesions in locally rapidly enlarging keratoacanthoma of the face is unusual and unreported to our knowledge. One case of simultaneous conjunctival and multiple, eruptive keratoacanthoma of the body has been reported. Patient 2 had received soft X-ray pretreatment because of a large, relapsing keratoacanthoma of the left cheek., Results: Patient 1 underwent a parallel, intensive treatment of the conjunctiva with 90Sr-contact therapy, percutaneous high-dose 60Co-gamma- and megavoltage electron treatment (10 and 18 MeV) of the midfacial lesions. Conjunctiva and caruncle showed a complete remission of keratoacanthoma. In the other facial areas no long-term regression could be reached, despite giving a fully cancericidal, total dose of more than 100 Gy in some regions. Patient 2: Further high dose radiotherapy using megavoltage electron treatment with a total dose of 50 Gy showed a complete remission of the lesion for 5 months. Another relapse of this keratoacanthoma could be operated successfully. There was no more relapse established in follow-up checks., Conclusions: The 2 case reports show that in treatment of locally destructive growing subsets of keratoacanthoma a sufficient therapy should be initiated in time. Keratoacanthoma and subsets of this lesion that do not respond well to initial treatment, recur early or show seriously aggressive growth should be treated early by combined therapy that takes previous experiences into consideration.

Antioxidants play an important role in the regulation of phospholipid hydrolysis and arachidonate metabolism. Supplementation of cultured human mesangial cells with selenium resulted in suppression of phospholipase A2-activity and significantly increased production of three major prostaglandins. However, prostacyclin synthesis benefits most from selenium supplementation, suggesting that there is a specific action of selenium-dependent glutathione peroxidase on this pathway. Like in endothelial cells, production of platelet activating factor is significantly inhibited by selenium supplementation.

Selenium is an essential component of glutathione peroxidase, an enzyme which protects cells against peroxidation and controls concentrations of intracellular peroxides. Since selenium deficiency is clinically associated with an increased degree of atherosclerosis, the effects of selenium deficiency on prostacyclin (PGI2) and platelet activating factor (PAF) production by cultured human umbilical vein endothelial cells (HUVEC) were investigated. In selenium-deficient HUVEC, histamine-induced PGI2 synthesis was significantly decreased when compared to selenium-supplemented HUVEC; in contrast, histamine-induced PAF production was increased by selenium deficiency. Histamine-induced inositol trisphosphate and [Ca2+]i responses and the conversion of PGG2 and PGH2 to PGI2 were not altered by selenium deficiency. However, selenium deficiency decreased the conversion of exogenous arachidonate to PGI2 and markedly suppressed glutathione peroxidase activity. These results suggest that selenium deficiency, by decreasing glutathione peroxidase activity, makes HUVEC susceptible to peroxide-induced inhibition of the cyclooxygenase activity of PGH2 synthase, resulting in decreased PGI2 production. These changes may alter platelet function in vivo and thus play a role in the increased incidence of atherosclerosis reported in selenium-deficient individuals.

Se is an essential component of glutathione peroxidase and thereby protects cells against peroxidation of their membrane lipids. Dialysis patients have significantly lower plasma Se levels than healthy controls. The obvious role of Se in protection against development of certain forms of cardiomyopathy was investigated for the case of blood cells. There is evidence that decreased half-lives of erythrocytes and thrombocytes, found in dialysis patients, correlate with degree of Se deficiency.

Five different hemoperfusion devices have been used in the treatment of patients, intoxicated with barbiturates. The changes in drug clearance values which occurred during hemoperfusion varied according to the device used. Even after very long periods of hemoperfusion, however, drug clearance values never fell to zero. Using data collected from comparable cases, it has been shown that the rate of uptake of drug from the blood is independent of the amount of adsorbent in the columns, those containing 100 gm charcoal having the same efficiency as the conventional 300 gm. The prime factor which determines the rate of drug uptake has been shown to be the arterial plasma drug concentrations. Other factors, such as the deposition of cellular debris and proteins as hemoperfusion progresses, are also thought to influence the efficiency of drug removal.

A combined intravenous and oral dosage regime for mexiletine has been evaluated in volunteer subjects. Therapeutically effective plasma concentrations of the drug were achieved rapidly and maintained over a four-hour period. Side-effects were minimal and the scheme would be suitable for the anti-arrhythmic protection of patients being transported to hospital and for the treatment of patients receiving hospital or, even, domicilliary care.

Fifteen patients who were severely poisoned with either hypnotic drugs or salicylate were treated by charcoal haemoperfusion. The device contained 100g of activated charcoal immobilised by fixation to a polyester film. Two patients showed no response and eventually died. The remainder showed marked lightening of coma and recovered uneventfully. Complications of platelet loss and, in one patient, fibrinolysis were observed, but these had no serious consequences. No significant biochemical disturbances occurred with the exception of one patient who presented with hypocalcaemia and required intravenous calcium throughout the treatment. Drug clearance values were comparable with those obtained with columns containing 300 g of acrylic polymer coated charcoal.