The question of dose-effect relations of berylliosis was examined by measuring the Be-concentration in blood and urine, as well as the immunological behaviour of T-lymphocytes for a group of occupationally exposed men (smaller than 8 ng Be/m3, 4-6 h daily) and a non-exposed control group. Normal values 1.0 +/- 0.4 ng Be/g(n=10) in blood and 0.9 +/- 0.5 ng Be/g(n=10) in urine were found by an optimized flameless atomic absorption spectrometry method. The corresponding values for the exposed group (n=8) showed a mean increase of a factor of 4. The preferential enrichment of Be in the prealbumin and in the nu-globulin fractions was determined by a preparative isotachophoretic column with physiological pH conditions, especially developed for this application. The Be-specific stimulation of the T-lymphocytes of the exposed group was increased significantly. In blood and urine samples of exposed (2-40 mg Be/m3 as Be(NO3)2) Wistar-rats and guinea pigs Be values up to 36 ng Be/g in serum and up to 300 ng Be/g in urine were determined. After Be exposure, guinea pig serum showed a significant increase in the nu-globulins after the isotachophoretical separation of the serum proteins, which could not be correlated with increased Be-levels in this fraction. 70% of the total Be(10-100 ng/g serum) were detected in the prealbumin, only about 1% in the nu-globulin fraction. The same results were found in serum samples with in vitro addition of Be. The lymphocyte transformation rates for the exposed animals were increased. Skin tests were found to be positive in 70% for exposed rats and in 50-70% for guinea pigs.
An accidental exposition of 25 persons to beryllium dust was used to follow up trace analytical and clinical parameters over a period of 10 months. Although no exposed person shows any symptoms of an acute beryllium intoxication, up to 5-fold increased beryllium concentrations could be analysed in serum samples about 10 hours after exposition. The beryllium clearance shows a biological half time in the range of 2 to 8 weeks. The beryllium determination in the nanogram range was carried out using a combined method by flameless a.a.s. with a detection limit of 0.6 ppb Be and a relative standard deviation from 20 to 4% in relation to the concentration range of beryllium measurement.Beryllium analyses are completed by thorax X-ray, spirometry, y-globulins and liver enzymes (SGOT, SGPT), which have shown no pathological values. Because it is known for beryllium to sensitize the cellular immune response, neopterin measurement was used to determine the activity of the immune system. Neopterin, a pteridine synthesized by activated macrophages after stimulation by gamma-interferon derived from sensitized T-lymphocytes, was determined in urine samples by HPLC combined with an fluorescence detector. Only in two cases a slight increase of neopterin has been found. As a result of this study it can be summarized, that a short-time exposure †Presented 22nd January 1986 at the 2nd IAEAC Workshop on Carcinogenic and/or Mutagenic Metal Compounds, CH-1884 Villars-sur-Ollon. 163 Downloaded by [Cornell University Library] at 02:16 19 November 2014 164 H. ZORN, Th. STIEFEL AND H. PORCHERto beryllium (10-20 h), which results in a increase of beryllium in serum to the fivefold normal beryllium level, does not initiate any symptoms of an acute beryllium intoxication. The exposed persons are controlled in future to evaluate the further course.
Die Proliferation von Tumorzellen wurde durch Applikation oder Inkubation mit xenogenen Leberpräparationen in vivo und in vitro gehemmt. Prophylaktische Injektionen dieser Präparate hemmten die Entwicklung subkutaner implantierter Meth-A-Sarkome. Darüber hinaus konnten etablierte Tumoren durch Therapie zur Regression gebracht werden. Präparationen aus anderen xenogenen Organen wie Thymus, Plazenta und Hirn hatten eine ähnliche Wirksamkeit. Besonders effektiv war eine Mischung aus verschiedenen xenogenen Materialien. Die antitumorale Wirkung von noch tolerierbaren Dosen von Cyclophosphamid konnte im untersuchten Meth-A-Sarkom übertroffen werden. Die Präparationen waren in Maus und Ratte nebenwirkungsfrei. Diese Befunde konnten durch Ergebnisse in der Gewebe-kultur an humanen Tumorzellen gestützt und erweitert werden. Diese neuartige, antitumorale Wirkung xenogener Gewebe in vivo wird als eine Verstärkung der körpereigenen Abwehr interpretiert. Die Ergebnisse der Gewebekultur sprechen aber auch für einen direkten regulativen Effekt auf die Zelle.
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