The role of T3 surface molecules in the activation of human T cells: a two-stimulus requirement for IL 2 production reflects events occurring at a pre-translational level

The human T cell leukemia Jurkat was used as a model to examine the requirements of T cell activation. These studies demonstrated that antibodies reactive with the T cell-specific T3 antigen were insufficient to result in the activation of Jurkat cells, determined by the secretion of IL 2. IL 2 production occurred only in the presence of a second stimulus, the phorbol ester PMA. With the use of an IL 2-specific cDNA probe, the appearance of IL 2 RNA, similarly, occurred only when cells were stimulated with both anti-T3 antibodies and PMA. These results demonstrate a two-stimulus requirement for gene expression in human T cells.     

Prostaglandin 12 reduces activation of human arterial smooth muscle cells in-vivo

Patients suffering from peripheral vascular disease have been “ultima ratio”-treated with PGI2 at a rate of 5 ng/kg/min for 6 hours a day and 5 consecutive days i.v. 20 of them underwent surgery thereafter as therapy was not sufficient. A histological examination and quantification of vascular tissue revealed that the number of activated smooth muscle cells was significantly lower in treated patients vascular segments than in untreated ones in all the different age groups. A comparable suppression was found in the intima and the media as well. It is thus concluded, that PGI2 inhibits smooth muscle cell proliferation most probably by inhibiting PDGF-release from the platelets and stimulation of smooth muscle cell cAMP. To achieve a more beneficial PGI2-effect at the vascular level, a prolonged PGI2-therapy looks rather promising.     

Operant behavior in transition reflects neonatal exposure to cadmium

Male Long-Evans rats were injected with 0, 1, 3, or 6 mg/kg of cadmium chloride on the first day of life. Animals free of morphological stigmata at weaning were selected for study. Tissue concentrations of cadmium and operant behavior under various fixed-ratio (FR) schedules of reinforcement were evaluated when these rats were adults. Dose-related increases in cadmium were present in the brains, livers, and kidneys. Dose-related differences in behavior were most evident during the transition from fixed ratio 25 (FR 25 or 25 responses/reinforcer) to FR 75. An inverted U describes the relationship between response output during the transition to FR 75 and cadmium chloride dose response output increased at 3 mg/kg and decreased at 6 mg/kg. The rate decreases were not correlated with weight loss that appeared after some of the animals exposed to 6 mg/kg reached 60 days of age. Challenge doses of d-amphetamine revealed no interaction between neonatal exposure to cadmium and d-amphetamine. The occurrence of alterations in operant behavior in animals that appeared normal on a number of preweaning evaluations suggests that operant behavior in transition was sensitive to subtle effects not observed with other commonly used tests. The data provide evidence for delayed effects in the adult that are due to neonatal exposure to cadmium.     

Analysis of the energy metabolism after incubation of Saccharomyces cerevisiae with sulfite or nitrite

After addition of 5 mM sulfite or nitrite to glucose-metabolizing cells of Saccharomyces cerevisiae a rapid decrease of the ATP content and an inversely proportional increase in the level of inorganic phosphate was observed. The concentration of ADP shows only small and transient changes. Cells of the yeast mutant pet 936, lacking mitochondrial F₁ATPase, after addition of 5 mM sulfite or nitrite exhibit changes in ATP, ADP and inorganic phosphate very similar to those observed in wild type cells. They key enzyme of glucose degradation, glyceraldehyde-3-phosphate dehydrogenase was previously shown to be the most sulfiteor nitrite-sensitive enzyme of the glycolytic pathway. This enzyme shows the same sensitivity to sulfite or nitrite in cells of the mutant pet 936 as in wild type cells. It is concluded that the effects of sulfite or nitrite on ATP, ADP and inorganic phosphate are the result of inhibition of glyceraldehyde-3-phosphate dehydrogenase and not of inhibition of phosphorylation processes in the mitochondria. Levels of GTP, UTP and CTP show parallel changes to ATP. This is explained by the presence of very active nucleoside monophosphate kinases which cause a rapid exchange between the nucleoside phosphates. The effects of the sudden inhibition of glucose degradation by sulfite or nitrite on levels of ATP, ADP and inorganic phosphate are discussed in terms of the theory of Lynen (1942) on compensating phosphorylation and dephosphorylation in steady state glucose metabolizing yeast.Abbreviations ATP adenosine triphosphate - ADP adenosine diphosphate - AMP adenosine monophosphate - P_i inorganic orthophosphate Dedicated to Prof. Dr. Hans Grisebach on the occasion of his sixtieth birthday     

Thermotoga maritima sp. nov. represents a new genus of unique extremely thermophilic eubacteria growing up to 90°C

A novel type of bacterium has been isolated from various geothermally heated locales on the sea floor. The organisms are strictly anaerobic, rod-shaped, fermentative, extremely thermophilic and grow between 55 and 90°C with an optimum of around 80°C. Cells show a unique sheath-like structure and monotrichous flagellation. By 16S rRNA sequencing they clearly belong to the eubacteria, although no close relationship to any known group could be detected. The majority of their lipids appear to be unique in structure among the eubacteria. Isolate MSB8 is described as Thermotoga maritima, representing the new genus Thermotoga.Dedicated to Otto Kandler on the occasion of his 65th birthday Present addresses: University of South Dakota, Vermillion, USA; University of Illinois, Urbana, USA; Universität für Bodenkultur, Wien, Austria     

Cytochrome c oxidase. Time dependence of optical and EPR spectral changes related to the ‘oxygen-pulsed’ form

Time-dependent changes in the optical spectrum (450–920 nm) of cytochrome c oxidase, following oxidation with oxygen of the stoichiometrically reduced form, have been investigated and where possible, attempts have been made to correlate our observations with variations in the EPR spectrum over a parallel time course at 2°C. In this regard, particular emphasis has been placed on establishing absorption features related to the presence of EPR resonances at g 5, 1.78 and 1.69, which have been tentatively assigned to a spin-coupled state involving cytochrome a₃ and ‘EPR-undetectable Cu’ (Beinert, H., Shaw, R.W., Dunham, R.W. and Sands, R.H. (1982) in Oxidases and Related Redox Systems (King, T.E., Mason, H.S. and Morrison, M., eds.), Pergamon Press, Oxford, in the press). For optical studies we have used a versatile rapid-scanning spectrophotometer to obtain well resolved spectra down to 2 ms reaction time. Concomitant with the appearance (within 10 ms) of EPR signals at g 5, 1.78 and 1.69 is the presence of an enhanced absorption (Δε = 0.25 mM (heme a)^?1·cm^?1) at 660 nm, with a trough (relative to following spectra) at 580 nm. In our hands, this feature disappears in a first-order process with a half-life of 46 s at pH 7.2 and 2°C. The effect of this spectral transformation is to decrease considerably the acuteness of the 655 nm absorption band, previously suggested as representing a state of the enzyme in which ferric cytochrome a₃ is coupled to oxidised EPR-undetectable Cu (Beinert, H., Hansen, R.E. and Hartzell, C.R. (1976) Biochim. Biophys. Acta 423, 339–355). This observation can be correlated satisfactorily with a small field shift of the high-field resonances at g 1.78 and 1.69 and a broadening at g 1.78. Support for this and further correlative assignments arises from parallel experiments using cytochrome c oxidase purified via an alternative procedure, which displays different kinetic behavior. Further transformations of the oxidized enzyme are evident through an approx. 10% decrease in absorbance at 600 nm together with small changes centered at 640 and 665 nm (which serve to restore the sharpness of the 655 nm band). The kinetics, as analyzed by the Guggenheim procedure using the absorbance at 597 nm, indicate approx. 50% first-order linearity (half-life 40 min) with additional species contributing at longer times, while over a parallel time course (0–3 h) the EPR resonances at g 5, 1.78 and 1.69 virtually disappear. These novel signals can also be seen at a lower intensity in samples of cytochrome c oxidase anaerobically reoxidized by porphyrexide and frozen after a 6 min incubation period at 4°C. This observation, along with the establishment of similar optical changes over the time course of 1 min to 3 h, suggests that aerobic and anaerobic reoxidation produce common forms of the enzyme. Comparison of the g 1.78 and 1.69 resonances between samples rapidly aerobically reoxidized in the presence of H₂¹⁶O and H₂¹⁷O yielded no evidence for the presence of any labile oxygen ligand (including OH^?, H₂O) in the coordination sphere of the species involved.     

Plasmodium berghei: a mouse model for the "sudden death" and "malarial lung" syndromes

A mouse model for the "sudden death" and "malarial lung" syndromes is described. Mice of the C3H/z strain succumb suddenly approximately 7 days after an infection with Plasmodium berghei becomes patent, at a time when parasitemia is still moderate (6 to 8%). Death could be shown to be due to anaphylactoid shock, probably induced by soluble immune complexes. Increased vascular permeability caused transudation and leakage of serum proteins into the interstitium and the alveoli. The lungs were found to be edematous, with a fine granular precipitate in the alveoli and adherent to the vascular walls. The precipitates reacted with antiglobulins G and M, and could be shown to also contain malaria antigens and C3/4. A dramatic drop in hematocrit was recorded several hours before death, indicating the sudden release of malaria antigens. The myocardium of animals that had died very suddenly showed a patchy loss of phosphorylase activity. This loss of activity was much more extensive, and sometimes almost total, when there had been an agonal period of several (1 to 3) hours before death. In these cases the irreversibility of the myocardial damage was also indicated by the loss of activity of the dehydrogenases, as well as by typical inflammatory reactions of granulocytic and histiocytic infiltrations. The hearts thus presented a typical picture of the acute and peracute shock syndromes. In acute shock cardiac insufficiency develops so suddenly that death ensues before irreversible damage has occurred, and cardiac insufficiency can only be demonstrated by the most sensitive of enzyme histochemical means. In the present case shock was induced by the anaphylactoid activity of immune complexes with the lung as target organ. The described syndrome appears analogous to human "malarial lung."     

Biphasic culture system for rapid Campylobacter cultivation.

We developed a biphasic culture system consisting of 4 ml of brucella agar (BA) and 6 ml of brucella broth (BB) in 25-cm2 tissue culture flasks, which were incubated in air (BB/BAa) or in a gas mixture of 5% O2, 10% CO2, and 85% N2 (BB/BAg). These media were also used with a supplement consisting of ferrous sulfate, sodium metabisulfite, and sodium pyruvate and incubated as above (FB/FAa and FB/FAg, respectively). Highly satisfactory growth of Campylobacter jejuni 301 was obtained with all medium-gas phase combinations provided that the number of viable cells in the inoculum was large (greater than or equal to 10(6)/ml). The use of FB/FAa permitted the inoculum to be reduced to 100 cells per ml. With an adjusted gas phase (BB/BAg and FB/FAg), near-optimal growth was obtained from an inoculum of 1 to 10 cells per ml. Under most of these conditions the generation time was approximately 90 min. During the logarithmic growth phase, the cells retained their typical spiral morphology and high motility. These media also proved to be highly satisfactory for the cultivation of fresh isolates as well as other stock strains of Campylobacter. When the broth phase of the cultures, after addition of 15% glycerol, was quickly frozen and maintained at -70 degrees C, all strains thus far examined were readily recoverable and satisfactorily cultivated without additional passage.     

Tissue-specific expression of the rat glutathione S-transferases

Tissue-specific patterns of rat glutathione S-transferase expression have been demonstrated by in vitro translation of purified poly(A) RNAs and by protein purification. Poly(A) RNAs from six rat tissues including heart, kidney, liver, lung, spleen, and testis were used to program in vitro translation with the rabbit reticulocyte lysate system and [35S]methionine. The glutathione S-transferase subunits synthesized in vitro were purified from the translation products by affinity chromatography on S-hexylglutathione-linked Sepharose 6B columns. The affinity bound fractions were analyzed by Na dodecyl SO4-polyacrylamide gel electrophoresis and fluorography. A subunit of Mr = 22,000 detected in the in vitro translation products of poly(A) RNAs from heart, kidney, lung, spleen, and testis is missing from the translation products of liver poly(A) RNAs. This Mr = 22,000 subunit is present only in the anionic glutathione S-transferase fraction purified from rat heart, kidney, lung, spleen, and testis. Purified anionic glutathione S-transferase from rat liver does not contain this subunit. The relative specific activities toward a dozen different substrates also demonstrate the nonidentity between liver and kidney anionic glutathione S-transferases. In addition, among the glutathione S-transferase subunits expressed in the liver, some of them could not be detected in the other tissues investigated. Our results indicate that tissue-specific expression of rat glutathione S-transferases may occur pretranslationally.