Early foetal thrombosis induced by Thalidomide in mouse: Possible explanation for teratogenicity

Summary Mouse foetuses were treated by Thalidomide on days 11–12 in order to verify whether the drug would induce blood abnormalities leading to circulatory troubles. About 18% of the treated foetuses showed both severe limb haemorrhages on day 14, and obvious alterations of the nucleated red blood cells of vitelline origin. These blood abnormalities, occurring suddenly during the well-known critical stage of foetal development, could be responsible for circulatory blocks leading to necrosis.     

Storage of irradiated human blood; a source of error in quantitative chromosome analysis

Summary Human whole blood was irradiated with 2.5 Gy of 220 kVp X-rays and stored before culture with 9.7 M BrdU and 19.4 or 38.7 M BrdU for 0, 24, 48 and 72 h. The frequency of dicentrics and ring chromosomes was determined in cells staining as first division (M1) metaphases with the fluorescence plus Giemsa technique. Storage had no influence on the observed aberration yields in 44 h cultures containing 9.7 M BrdU. In 66 h cultures at 19.4 M BrdU the observed yields after 2 and 3 days' storage were significantly lower as compared to cultures from fresh blood. No storage effect was revealed in 66 h cultures containing 38.7 M BrdU. In cases where cytogenetic radiation dosimetry has to be carried out using blood samples which have been in transit for 2–3 days, the findings are of relevance for a correct determination of the chromosome damage in M1 cells.     

Effect of α- and β-ecdysone on DNA synthesis inAeshna cyanea (Insecta,Odonata) midgut

Summary InAeshna cyanea larvae, - and -ecdysone stimulate DNA synthesis in the midgut regenerative cells. In last larval instar, the number of cells obtained after the imaginal epithelium genesis is greater after - than after -ecdysone supply. Such a result should be compared with the imaginal epithelium differentiation which occurs earlier after -ecdysone injection.     

In vivo incorporation of14C-phenylalanine into ascidian tunichrome

Ascidia ceratodes exposed to¹⁴C-phenylalanine in the surrounding seawater incorporates the radiolabel into newly biosynthesized tunichrome molecules. Radioactivity can be detected in tunichrome extracted from circulating blood cells within one day following initial exposure to the radiolabel; weak activity (4 Ci/mol tunichrome=22 nmol phenylalanine/mol tunichrome) is detected in 1 to 10 days; significantly higher amounts of radiolabel (57 Ci/mol tunichrome=318 nmol phenylalanine/mol tunichrome) appear 20 days after seawater exposure. Therefore, phenylalanine can function as a precursor in the biosynthesis of tunichrome.     

Alterations ofβ-adrenoceptor-density and cAMP-synthesis in rat-erythrocytes after stress erythropoiesis

Summary During the maturation of red blood cells from rats after stress erythropoiesis, adenyl cyclase activity and -adrenoceptor density (pmoles/mg protein) decrease at distinctly different rates suggesting a different turnover of these membrane units.Acknowledgments. This work was supported by the Deutsche Forschungsgemeinschaft. The skillful technical assistance of Mrs I. Groth and Mrs C. Kiele is gratefully acknowledged. The liquid scintillation spectrometer was a gift from the Dr Robert-Pfleger-Stiftung.     

Induction of lymphokine-activated killer cells from nude mouse spleen cells by interleukin-4

The induction of lymphokine-activated killer (LAK) cells from natural killer (NK) lineage cells by interleukin-4 (IL-4) was studied in vitro. Activation of nude mouse spleen cells by IL-4 generated cytotoxic cells, capable of killing NK-sensitive as well as NK-resistant tumor cells. The induction of peak lytic activity was demonstrated after 3 days of culture with IL-4. Surface marker analysis indicated that the majority of precursor cells were aGM1⁺, Thy1^–, and the majority of effector cells were aGM1⁺, Thy1⁺, suggesting that IL-4 induced LAK cells from nude mouse spleen cells were similar to those from normal mouse spleen cells. The induction of nude mouse LAK cells by IL-4 was partially inhibited by anti-IL-4 or anti-interferon (IFN)-, antibody, and it was further inhibited by the combination of two antibodies, suggesting that IFN-, production was associated with LAK induction of NK lineage cells by IL-4.     

Immunomodulating effects in vitro of a hydroxythiazolobenzimidazole in the absence of mitogenicity

Summary Wy-13, 876, a hydroxythiazolobenzimidazole, enhanced in vitro antibody formation by mouse spleen cells immunized with sheep red blood cells. The optimal dose was 25–50 g/culture. The compound did not have a mitogenic effect at any dose.     

Suppression of delayed type hypersensitivity of mice by lead

Summary Application of lead suppressed the delayed type hypersensitivity (DTH) of mice induced by sheep red blood cells (SRBC). Inhibition of elicitation of DTH in primary as well as in secondary response was correlated with the concentration of lead in the blood of the mice.Acknowledgments. Supported by the Georg-und-Agnes-Blumenthal-Stiftung and the Verein für Wasser-, Boden- und Lufthygiene. We thank Miss Schachtschneider for the excellent technical assistance.     

Undulating tubules in lymphocytes of an apparently healthy human donor

Summary So-called undulating tubules were found in the blood lymphocytes of an apparently healthy 33-year-old male. Undulating tubules have been noted to occur frequently in kidney cells and blood lymphocytes of patients suffering from collagen diseases and especially from SLE. They have been suggested to be a possibly pathognomonic finding in such diseases. Our result seems to contradict such an association.     

Immunohistochemical study of the pars intermedia of the mouse pituitary in different experimental conditions

Summary -MSH, -MSH and ACTH bave been localized in the cells of hypophyseal intermediate lobe by fluoresence histoimmunological technics. Elaboration and excretion of these polypeptides are enhanced after dehydration or adrenalectomy. The most evident variations are seen with -MSH and ACTH after dehydration, with -MSH after adrenalectomy.